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can i hook up a marshall mg100hdfx headstock to a fender frontman 212r


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#1 jeff12623

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Posted 26 February 2010 - 01:41 PM

I recently purchased a marshall mg100hdfx headstock, and I currently don't have enough money to get a cab. I have no experience with half stacks so I was wondering if it would be possible to hook up my marshall head to my fender fronman 212 r and use that as a cab for the time being until i get enough money to buy a cab to go with the headstock, and if it is possible how would I go about doing it.

Edited by jeff12623, 26 February 2010 - 02:30 PM.


#2 surfwhammy

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Posted 27 February 2010 - 09:13 AM

I recently purchased a marshall mg100hdfx headstock, and I currently don't have enough money to get a cab. I have no experience with half stacks so I was wondering if it would be possible to hook up my marshall head to my fender fronman 212 r and use that as a cab for the time being until i get enough money to buy a cab to go with the headstock, and if it is possible how would I go about doing it.


The "100" part of the name of your Marshall® amplifier refers to the amplifier (or "head") having a power output rating of 100 watts (100W) RMS (root mean square), and since the Fender® Frontman® 212R 100W 2x12 Guitar Combo Amp has two 12" loudspeaker that are rated at 100W RMS (as a pair, not separately), there is a way to use the Marshall amplifier to drive the Fender loudspeakers . . .

Doing what you want to do is a trivial modification, and it takes someone who knows how to do the work and has the required parts less time that it will take me to explain it in writing . . .

From the perspective of the Marshall MG100HDFX amplifier, there are three important criteria:

(1) It needs a minimum load of 4 Ohms, with higher values being OK (for example, 8-Ohms or 16-Ohms) . . .

(2) It needs to be connected to a loudspeaker or a set of loudspeakers that have a combined power-handling rating of 100-watts RMS or higher . . .

(3) You need to use a non-shielded ("non-screened" in UK terminology) speaker cable to connect the amplifier to the loudspeakers. In other words, do not use a shielded or "screened" guitar cord. It must be a speaker cable for connecting an amplifier to one or more loudspeakers . . .

You can determine this information by downloading the owner's manual ("handbook" in the UK) from the Marshall website . . .

Owner's Manuals ~ Handbooks (Marshall website)

For the Fender Frontman 212R 100W 2x12 Guitar Combo Amp, you only need to use the loudspeakers, but the way you do this is very important . . .

As you can determine by studying the specifications for the Fender Frontman 212R 100W 2x12 Guitar Combo Amp, which is found at the Fender website, the Fender Frontman 212R 100W 2x12 Guitar Combo Amp has a power output of 100W RMS at 4-Ohms, and the two 12" loudspeakers individually are rated at 50W RMS at 8-Ohms, but since they are wired in parallel, this maps to a combined impedance of 4-Ohms. If they were wired in series, then the combined impedance would be 16-Ohms . . .

Fender Frontman 212R 100W 2x12 Guitar Combo Amp (Specifications)

Based on your needing to ask how to do this, I think that the most practical solution is to take the Fender Frontman 212R 100W 2x12 Guitar Combo Amp to a music store or electronic repair shop and ask the amplifier technician to install a special output jack so that you can use the Marshall amplifier with the Fender loudspeakers. This should not be an expensive modification, and in the US it would cost from $25 to $50 . . .

As you can see in this photograph of the back of a Fender Frontman 212R 100W 2x12 Guitar Combo Amp, there are two wires that come from the amplifier and go to the loudspeakers, where one wire is white and the other wire is black . . .

Posted Image
Fender Frontman 212R 100W 2x12 Guitar Combo Amp ~ Back View

Posted Image
1/4" Output Jack ~ (Female, hence technically a "Jill" in the UK, but called a "Jack" in the US)

Posted Image
1/4" Output Jack ~ (Male, hence technically a "Jack" in the UK, but called a "TS" connector or a 1/4" male telephone Jack in the US)

[NOTE: Much to their credit as a nation with high natural levels of intuitive common sense, the British realized over a century ago that since a TS connector looks a bit like the reproductive organ of a male human, it should be called a "Jack", while the port into which the "Jack" plugs is best called a "Jill", but my fellow Americans often are a bit confused and tend to call everything a "Jack", which among other things has led to lower annual birthrates as well as an abundance of hair stylists, interior decorators, cosmetologists, dancers, and liberal Democrats . . . :D ]

The modification involves cutting the white and black wires and connecting the lower part of the two wires to a 1/4" output jack, which you can mount in a hole that you drill in the wooden part of the back or side of the Fender Frontman 212R 100W 2x12 Guitar Combo Amp enclosure . . .

These will be the two wires that go to the loudspeakers, and it is best to cut the wires midway so that you have enough wire to work with it easily . . .

You will need some extra wire of the same type and gauge, since you will need to make the wires that you just cut a bit longer, perhaps 12" to 18" . . .

The other ends of the two wires, which will be the pair that comes from the Fender amplifier will be connected to some additional wire of the same type and gauge, which you then will connect to a 1/4" TS Jack (male), so that when you want to use the Fender Frontman 212R 100W 2x12 Guitar Combo Amp as a combo unit, you can plug it to the output Jill that now goes to the two 12" speakers, but otherwise, you will unplug the new Fender amplifier output Jack from the new loudspeaker Jill and instead will connect the loudspeaker output of the Marshall amplifier to the new output jack for the Fender loudspeakers, via a non-shielded (or non-screened) speaker cable with 1/4" TS connectors on both ends, which looks a bit complicated when described in words, but actually is very easy to do if you know a little bit about electronics, operating a drill and soldering iron, and whatever . . .

Whatever!

Another way to solve the problem is to build a loudspeaker enclosure similar to a Marshall cabinet (closed back, filled with at least a little bit of fiberglass insulation) and to use the two 12" loudspeakers from the Fender amplifier in your custom-build loudspeaker cabinet. This has the advantage of getting a deep and rich TONE that will be more like the TONE of a Marshall 4x12 cabinet . . .

So, the summary is that there is a way to do what you want to do, but it requires a bit of knowledge and expertise on electronics, loudspeakers, and using the required tools, which is important, because it is very important to understand that if you do not know how to do all the work correctly, you can severely injure yourself or damage the amplifiers and loudspeakers, since electricity is not a toy . . . .

If you do a bit of reading and studying, you can learn how all this stuff works, as well as how to do the modifications, but it takes a while, and it is easier when someone who already knows how to do it can take the time to show you how to do it and to explain how everything works . . .

Hence, my advise is to take the Fender amplifier to a music store or electronics repair shop and have a professional electronics technician do the simple modification, as well as explaining how you will use it, and so forth, which is fabulous . . .

Fabulous! :)

P.S. If you are handy with woodworking tools and can build a loudspeaker cabinet, then the two 12" Fender loudspeakers will sound very good in a larger loudspeaker cabinet with a closed back and a bit of fiberglass insulation, and probably will sound as good or better than the Marshall loudspeaker cabinet which is recommended by Marshall for use with your Marshall amplifier. You can control the bass TONE by the way you design the cabinet and by how much fiberglass insulation you use, as well as whether you provide a bass reflex port for the cabinet, and this is what I probably would do if I did not have any additional need for the Fender combo amplifier, but it depends on what you want to do . . .

Yet another strategy is to build your own loudspeaker cabinet and to get two more loudspeakers for the custom-built cabinet . . .

Or, you could get a prebuilt PA-style loudspeaker cabinet, which is a very affordable solution, for example the $99 (US) Kustom KPC15" PA Speaker Cabinet with Horn . . .

Posted Image
Kustom KPC15 15" PA Speaker Cabinet with Horn (125W RMS at 8-Ohms) ~ Approximately $99 (US)

This will work nicely, and it has the advantage of not messing with your Fender combo amplifier, since with a PA-style loudspeaker cabinet, all you need is a speaker cable and your Marshall amplifier, for sure . . .

For sure!

P.S.S. Stuff like this is an excellent reason to stay awake during Physics classes, really . . .

Really! :)

Edited by surfwhammy, 27 February 2010 - 09:16 AM.

The Surf Whammys

Sinkhorn's Dilemma: Every paradox has at least one non-trivial solution . . .

#3 ElevenBravo

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Posted 23 September 2010 - 12:58 PM


I recently purchased a marshall mg100hdfx headstock, and I currently don't have enough money to get a cab. I have no experience with half stacks so I was wondering if it would be possible to hook up my marshall head to my fender fronman 212 r and use that as a cab for the time being until i get enough money to buy a cab to go with the headstock, and if it is possible how would I go about doing it.


The "100" part of the name of your Marshall® amplifier refers to the amplifier (or "head") having a power output rating of 100 watts (100W) RMS (root mean square), and since the Fender® Frontman® 212R 100W 2x12 Guitar Combo Amp has two 12" loudspeaker that are rated at 100W RMS (as a pair, not separately), there is a way to use the Marshall amplifier to drive the Fender loudspeakers . . .


@surfwhammy - Simply an awesome response to jeff12623's question! I mean simply awesome, man. So awesome that I felt compelled to register for the forums so that I could post this note. I have an FM212R and recently bought a Blues Deluxe Reissue. I was considering buying the matching Fender tweed 1x12 extension cab (about $300), but figured what the h3ll, I already own a 2x12 inside the Frontman combo. Let's hear how it sounds and decide whether the matching 1x12 extension cab is worth the money (I'm thinking *not*) or whether my $$ is better spent replacing the speakers inside the Frontman. I have already used both of the amps in tandem by way of the pre-amp out of the Deluxe into the Pwr Amp In on the Frontman and it took a bit of tweaking but I got the pair sounding decent with each other, the Deluxe stacked on top of the Frontman. It does look like a stack o' sound for sure. However, I would rather have the Frontman speakers driven directly by the tube power in the Deluxe. My Google search led me to your reply post. I wasn't sure if the Frontman speakers were wired in series or parallel, but I suspected parallel.

Quick question: There are 2 speaker output "jills" on the Deluxe. One jill is for the Internal spkr, the other for an External spkr. If only Internal spkr is connected to the amp, then it's 8 ohms impedance. Internal plus External connected = 8 ohms output impedance to each spkr, Int and Ext. If Internal jill is "open" (must use a dummy jack though) and only External has a load (such as from the Frontman), then External jill rates at 4 ohms impedance. Since the method you suggested in your post would represent 4 ohm impedence from the Frontman, should I be concerned about running the Deluxe amp with an 8 ohm load from the Internal spkr and a 4 ohm load from the Frontman simultaneously? Should be no problems to connect the Frontman by itself without the Internal spkr connected in the Deluxe because there is a 4 ohm to 4 ohm impedance match. It would only be a concern if the speaker cab impedence were *lower* than the output impedence from the amp, right? Such as 4 ohm output impedence from the amp into a 2 ohms impedence load from the speakers. Does this make sense? I just don't want to hurt my Deluxe amp through impedence mismatching.

Thanks in advance for any and all advise or cautions. I'm going to stop by the electronics shop tonight and get the connectors I need to start wiring up the Frontman.

Cheers,

~ Johnny
(aka ElevenBravo)

#4 surfwhammy

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Posted 23 September 2010 - 07:26 PM



I recently purchased a marshall mg100hdfx headstock, and I currently don't have enough money to get a cab. I have no experience with half stacks so I was wondering if it would be possible to hook up my marshall head to my fender fronman 212 r and use that as a cab for the time being until i get enough money to buy a cab to go with the headstock, and if it is possible how would I go about doing it.


The "100" part of the name of your Marshall® amplifier refers to the amplifier (or "head") having a power output rating of 100 watts (100W) RMS (root mean square), and since the Fender® Frontman® 212R 100W 2x12 Guitar Combo Amp has two 12" loudspeaker that are rated at 100W RMS (as a pair, not separately), there is a way to use the Marshall amplifier to drive the Fender loudspeakers . . .


@surfwhammy - Simply an awesome response to jeff12623's question! I mean simply awesome, man. So awesome that I felt compelled to register for the forums so that I could post this note. I have an FM212R and recently bought a Blues Deluxe Reissue. I was considering buying the matching Fender tweed 1x12 extension cab (about $300), but figured what the h3ll, I already own a 2x12 inside the Frontman combo. Let's hear how it sounds and decide whether the matching 1x12 extension cab is worth the money (I'm thinking *not*) or whether my $$ is better spent replacing the speakers inside the Frontman. I have already used both of the amps in tandem by way of the pre-amp out of the Deluxe into the Pwr Amp In on the Frontman and it took a bit of tweaking but I got the pair sounding decent with each other, the Deluxe stacked on top of the Frontman. It does look like a stack o' sound for sure. However, I would rather have the Frontman speakers driven directly by the tube power in the Deluxe. My Google search led me to your reply post. I wasn't sure if the Frontman speakers were wired in series or parallel, but I suspected parallel.

Quick question: There are 2 speaker output "jills" on the Deluxe. One jill is for the Internal spkr, the other for an External spkr. If only Internal spkr is connected to the amp, then it's 8 ohms impedance. Internal plus External connected = 8 ohms output impedance to each spkr, Int and Ext. If Internal jill is "open" (must use a dummy jack though) and only External has a load (such as from the Frontman), then External jill rates at 4 ohms impedance. Since the method you suggested in your post would represent 4 ohm impedence from the Frontman, should I be concerned about running the Deluxe amp with an 8 ohm load from the Internal spkr and a 4 ohm load from the Frontman simultaneously? Should be no problems to connect the Frontman by itself without the Internal spkr connected in the Deluxe because there is a 4 ohm to 4 ohm impedance match. It would only be a concern if the speaker cab impedence were *lower* than the output impedence from the amp, right? Such as 4 ohm output impedence from the amp into a 2 ohms impedence load from the speakers. Does this make sense? I just don't want to hurt my Deluxe amp through impedence mismatching.

Thanks in advance for any and all advise or cautions. I'm going to stop by the electronics shop tonight and get the connectors I need to start wiring up the Frontman.

Cheers,

~ Johnny
(aka ElevenBravo)


Welcome to GuitarZone! And I am glad you found the previous information helpful! :)

Toward the goal of answering your questions, the first step is to make a very important thing as clear as possible, which to be specific is that there are several separate activities, and they need to be kept separate . . .

(1) An electric guitar has an analog output signal, and it low-voltage and low-power but high-impedance. You can connect the output signal of your guitar to the input for an effects pedal; to the input of a guitar amplifier; to the input for a preamplifier; or to the input for a digital audio interface like the MOTU 828mk3, which converts the analog output signal of your guitar into a special type of digital signal that makes sense to a computer . . .

(2) A guitar amplifier has inputs, but some guitar amplifiers also have special types of inputs and outputs called "sends" and "returns", all of which are at the same low-voltage, low-power and high-impedance as the analog output signal of an electric guitar (1). So, the analog output signal of your guitar is matched for use as the input signal to your amplifier, which is the correct usage. Also, you can use an amplifier "send" as a copy of your guitar output signal for purposes of "sending" the copy of your guitar output signal to an effects pedal, and when you do this you will connect the output signal of the effects pedal to the "return" on your amplifier, where for each "send" on the amplifier there should be a matching "return", since these usually are done in pairs (send, return) . . .

(3) Completely separate from (1) and (2), your guitar amplifier has a loudspeaker output, and this loudspeaker output is very different from (1) and (2), because it is a higher-voltage and higher-power but typically low-impedance output, although the "higher-voltage" is relative to the electric guitar output and amplifier input being "low-voltage", which is a roundabout way of explaining that the loudspeaker output of a typical guitar amplifier is nowhere even near to the voltage of a high-power electricity power line that might supply electricity to a city or whatever, but the loudspeaker output is a higher-voltage than the voltage of the output signal of an electric guitar . . .

In some respects, all this stuff is a bit complex, but so what . . .

So what!

From a practical perspective, the important thing for guitar players is to understand that the output jill of an electric guitar connects to the jack at one end of a guitar cord, and then the other end of the guitar cord, which also is a jack, is plugged into the input jill of a guitar amplifier. Or you can connect a guitar cord to your guitar and connect the other end of the guitar cord to an effects pedal, since everything is designed to work correctly this way. If you "run" the guitar to an effects pedal, where "run" is a bit of technical jargon for "connect and so forth", then you will want to connect another guitar cord to the output of the effects pedal, where you can either connect the other side of that guitar cord to another effects pedal or directly to the input jill of the amplifier. When you run a guitar to an effects pedal and then connect the output signal of the effects pedal to another effects pedal, you are creating a "chain" of effects pedals, which typically is the way it is done, but at the end of the "chain", which nearly always is the last effects pedal in the "chain", its output signal is connected to the input jill of the amplifier, and this works nicely because everything is matched in terms of voltage, power, and impedance . . .

And although it would not make any sense, you could connect your guitar to a non-powered loudspeaker cabinet, but the output signal of your guitar is so weak that it would not have enough power actually to cause the loudspeaker cabinet to make noise, which is the reason it makes no sense . . .

Everything is important, but it is especially important to understand that you cannot run the loudspeaker output signal of one amplifier to the input jill of a second amplifier, because loudspeaker output signals are vastly too powerful . . .

Explained another way, in the days when people used horses for pulling wagons filled with bales of hay, someone decided to do a few measurements of typical horses, which led to the definition of "horsepower", which basically maps to the work that one horse can do in a second or whatever, where the general idea according to wikipedia was to be able to compare steam engines to draft horses, where "draft horses" are horses that are specifically bred for pulling wagons or something . . .

Horsepower (wikipedia)

The simplistic view is that one horsepower is the amount of work that one horse can do at any time, so for example if you had two horses, then you would have two horsepower . . .

To put the loudspeaker output of a guitar amplifier into perspective, one way to do this is to understand that one horsepower is approximately equal to 767 electrical watts . . .

So, one can suggest accurately that playing an electric guitar through eight 100-watt Marshall stacks produces as much loudspeaker output power as one horse . . .

The more modern version is that eight 100-watt Marshall stacks produce about as much loudspeaker output power as a 1-Horsepower lawnmower engine, which leads directly to the analogy that you would need to play electric guitar through eight 100-watt Marshall stacks at full volume for about four hours to mow a one-acre yard if the grass was not too high . . .

Or, you could mow the grass of a 1/8 acre yard by playing your guitar through a single 100-watt Marshall stack at full volume for 30 minutes . . .

Hence, if you run the loudspeaker output from your amplifier directly into the input of a second amplifier, this obviously causes problems for two reasons, one of which is that the second amplifier is not a yard of grass that needs to be mowed . . .

[IMPORTANT: After making sense of the terminology Fender uses for what I call "Send" and "Return", you cannot and must not run the loudspeaker output of an amplifier to the "Power Amp In" or "PWR IN" jill, because these are "Returns" and they expect a signal about the same as a guitar, not a high-power loudspeaker output signal, as explained below. The really should have called them "Send" and "Return" or "Effects Send" and "Effects Return" to avoid confusion . . . ]

In other words, you want to connect similar things to similar things, and the loudspeaker outputs of amplifiers are connected to loudspeakers NOT to the inputs of amplifiers and NOT to the sends and returns of the preamplifier section of an amplifier . . .

There is a way to connect part of an amplifier to another amplifier, but this is done via sends and returns or special outputs that are designed specifically to run part of an amplifier's signal to another amplifier, where this typically involves running the preamplifier output signal to the input jill of a second amplifier, so instead of cascading power amplifiers, you are cascading preamplifiers and then at the end of the chain you run that amplifier's preamplifier output to the power amplifier section that creates the loudspeaker output that powers the loudspeakers . . .

And I think that we are on the same page in this respect, since you discovered how to run the preamplifier output of your Blues Deluxe Reissue to the power input of your Frontman, which is fine . . .

However, this is where it there is a bit of confusion regarding (1), (2), and (3) as described above:

should I be concerned about running the Deluxe amp with an 8 ohm load from the Internal spkr and a 4 ohm load from the Frontman simultaneously? Should be no problems to connect the Frontman by itself without the Internal spkr connected in the Deluxe because there is a 4 ohm to 4 ohm impedance match. It would only be a concern if the speaker cab impedence were *lower* than the output impedence from the amp, right? Such as 4 ohm output impedence from the amp into a 2 ohms impedence load from the speakers. Does this make sense? I just don't want to hurt my Deluxe amp through impedence mismatching.


[NOTE: Depending on the way this is read, if you are asking if you can connect the Blues Deluxe Reissue "Main Speaker" to the Blues Deluxe Reissue loudspeaker and then connect the two Frontman loudspeakers wired in parallel to the "External Speaker" of the Blues Deluxe Reissue, then to be as safe as possible, the answer is "No!", because there is an impedance mismatch, since in this configuration, the "External Speaker" expects to see 8-Ohms but the two Frontman loudspeakers are 4-Ohms, which is an impedance mismatch, and it could damage the output transformer of the Blues Deluxe Reissue. However, you could connect only one of the Frontman loudspeakers to the "External Speaker", and it will be fine, since a single Frontman loudspeaker is 8-Ohms, which is what the "External Speaker" connection expects, but it is important that the "Main Speaker" be connected to the Blues Deluxe Reissue loudspeaker, since to get 8-Ohms for the "External Speaker", the "Main Speaker" needs to be connected to an 8-Ohm loudspeaker, as well. And while there is a way to separate the two Frontman loudspeakers, with using a special type of switch and a second jill being one way, it tends to complicate the wiring for the modification . . . ]

The best way to explain the way everything works is for you to consider that each unit (Blues Deluxe Reissue and Frontman) is not a "combo amplifier" but instead is what Fender calls a "piggyback" unit, where the amplifier is separate from the loudspeaker cabinet . . .

You can connect your electric guitar to the input of the Frontman and then run the preamplifier of the Frontman the power input of the Blues Deluxe Reissue amplifier, or if the Frontman has a send, you can run the send to the input of the Blues Deluxe Reissue amplifier, which is fine so long as the send does not require a matching return (see note regarding Fender terminology, below). And since both amplifiers have what I call a "Send" and "Return", you also can connect the "Preamp Out" of the Blues Deluxe Reissue to the "PWR IN" of the Frontman, but only if both amplifiers have loudspeakers connected (see the note below regarding the importance of having a loudspeaker connected to an amplifier before turning-ON the amplifier) . . .

What you cannot do is run the loudspeaker output of the Frontman to anything but loudspeakers . . .

And you cannot connect the loudspeaker outputs of two amplifiers to one loudspeaker . . .

So, the simple solution is to get both units configured as if they were "piggyback" units, which is what I explained in the previous post for the Frontman, where for the Frontman the two wires (black, white) coming from the power amplifier are the loudspeaker output, and you can see the terminals and wires for the two 12" loudspeakers of the Frontman . . .

And you want to do essentially the same thing with the Blues Deluxe Reissue, except that as best as I can determine, it already is done, but without actually being able to examine a Blues Deluxe Reissue unit or to see photograph of the two loudspeaker output jills and what I am presuming is a loudspeaker jack, all I can do is guess, but my best guess is that the two wires coming from the terminals on the 12" Special Design Eminence® 8 ohm, 50 watt loudspeaker end in a connector that looks like the connector at the end of a standard guitar cord, which will be a 1/4" telephone jack, which by default is plugged into "Main Speaker" jill of the Blues Deluxe Reissue . . .

This gets a bit complex, but so what . . .

So what!

When you do the modification to the Frontman that I referenced in my previous post, you will have either a jack or a jill for everything, at which time you can experiment with some of the various sensible combinations . . .

This is what we know about the loudspeakers of the two units (Frontman and Blues Deluxe Reissue):

(1) The Frontman has two loudspeakers that are rated at 50-watts at 8-Ohms each, and they are wired in parallel (which divides using a simple formula), so the impedance of the two loudspeakers wired in parallel is 4-Ohms. If they were wired in series (which adds), then the two loudspeakers wired in series would have an impedance of 16-Ohms, which is useful to remember . . .

(2) The Blues Deluxe Reissue has one loudspeaker that is rated at 50-watts and 8-ohms . . .

And this is what we know about the amplifier loudspeaker outputs of the two units (Frontman and Blues Deluxe Reissue):

(1) The Frontman amplifier produces a loudspeaker output of 100-watts at 4-Ohms . . .

(2) The Blues Deluxe Reissue amplifier produces a loudspeaker output of 40-watts at either 8-Ohms or 4-Ohms, depending on how the "Main Speaker" and "External Speaker" jills are used, where using the "External Speaker" jill requires either that there be an "open plug", with "plug" mapping to "jack", in the "Main Speaker" jack at which point the impedance is 4-ohms for the "External Speaker" or that a real loudspeaker jack be connected to the "Main Speaker" jill, which sets the "External Speaker" output to 8-Ohms . . .

We also know this stuff:

(1) Electric guitar output signals go to effect pedals or amplifier inputs . . .

(2) Sends go to effects pedals, and Returns come from effects pedals--and, since sends connect to effects pedals, this tells us that a Send is pretty much the same as the electric guitar output signal (1), although there can be sends from different places along the overall path, where for example some amplifiers have sends that are exactly the same as the output signal of an electric guitar but they also might have sends that come after the VOLUME and TONE controls on the amplifier, in which case another terminology from mixers is "pre-fader" and "post-fader", where "pre-fader" maps to being exactly like the original input but "post-fader" is the original input after it is modified by the VOLUME and TONE controls . . .

(3) Preamplifier-section outputs go to power amplifier-section inputs . . .

(4) Loudspeaker outputs go to loudspeakers or to loudspeaker cabinets that have loudspeakers . . .

[NOTE: Making this all the more complex, there actually is a way to add a few components to the loudspeaker output signal of a power amplifier so that you can connect it directly to the input of another amplifier, but forget about it, since it is too difficult to explain; it costs too much; it is of no practical value; and you are not going to do it, anyway) . . . ]

And there are some hard limits on what you can do, where one limit is the Frontman having a loudspeaker output of 100-watts at 4-Ohms, which maps to needing to connect it either to one 4-Ohm loudspeaker or to a set of loudspeakers that as a set have an impedance of 4-Ohms, which might be two 8-Ohm loudspeakers wired in parallel (which is what comes with the Frontman and maps to 4-Ohms) or some other combination that maps to 4-Ohms . . .

The Blues Deluxe Reissue can have either an 8-Ohm loudspeaker(s) output or a 4-Ohm loudspeaker output . . .

This is what you can do easily, although it requires either doing the Frontman modification I posted or doing a similar modification to the Frontman . . .

(1) You can use only the two loudspeakers of the Frontman either as the loudspeakers for the Frontman or as the loudspeakers for the Blues Deluxe Reissue, where for the Blues Deluxe Reissue usage you will put an "open plug" in its "Main Speaker" jill and then connect the two Frontman loudspeakers via their single cable to the "External Speaker" jill of the Blues Deluxe Reissue, which has everything at 4-Ohms, but you cannot turn-on the Frontman if you do this . . .

(2) If you put an output jill on each loudspeaker of the Frontman, then (2.1)you can connect one loudspeaker to the "Main Speaker" jill of the Blues Deluxe Reissue or (2.2) you can connect one loudspeaker to the "Main Speaker" jill and then connect the other loudspeaker to the "External Speaker" jill of the Blues Deluxe Reissue . . .

So, there are three ways that you can use the loudspeakers of the Frontman with the Blues Deluxe Reissue, but there are no ways for using the Blues Deluxe Reissue loudspeaker with the Frontman as the amplifier, other than to use it with just one of the Frontman loudspeakers, which probably is a bit strange, really . . .

Really!

These are the key bits of information:

(1) You have three 50-watt 8-Ohm loudspeakers (two in the Frontman cabinet and one in the Blues Deluxe Reissue cabinet) . . .

(2) You have two amplifiers (one Frontman amplifier with an output of 100-watts at 4-Ohms, and one Blues Deluxe Reissue amplifier with an output of either 40-watts at 8-Ohms or 40-watts at 4-Ohms) . . .

And after reading the Blues Deluxe Reissue owner's manual, what Fender is calling "Preamp Out" actually is what I call "Send" and what Fender is calling "Power Amp In" is what I call "Return", which also is the terminology Fender uses for the Frontman, except that they use abbreviations "PRE OUT" and "PWR IN", hence both the Blues Deluxe Reissue and the Frontman have what I call one "Send, Return" pair . . .

[IMPORTANT: If the power is turned-ON for an amplifier, then the amplifier must be connected to loudspeakers! ]

You can get a bit more information about the two units by downloading the owner's manuals from the Fender website, where this is the link for the PDF owner's manuals that can be downloaded. Fender also has owner's manuals and schematics for older units, but some of them are hard-copy so need to be ordered, where they charge a fee for making printed copies . . .

Electronic Product Owner's Manuals (Fender Support)

So, there are things you can and things you cannot do . . .

And there are a variety of modifications and enhancements you can do, with some of them being easy but others being a bit more complex . . .

Basically, you have two amplifiers (each with one "Send" and "Return" pair), and you have three 50-watt 8-Ohm loudspeakers (two in one cabinet and one in another cabinet). One amplifier has a 100-watt 4-Ohm output, but the other amplifier has a 40-watt output at either 4-Ohms or 8-Ohms, depending on the way its two output jills are plugged, where there must be at least one loudspeaker connected to one of the jills and so forth and so on . . .

And there are a few more useful bits of information:

(1) Based on the prices of the two amplifiers, my best guess is that the Blues Deluxe Reissue has a very good loudspeaker, but the Frontman does not have such stellar 12" loudspeakers . . .

(2) The Blues Deluxe Reissue is a high-quality amplifier, but the Frontman is not such a high-quality amplifier . . .

So, from a different perspective, it makes a bit of sense to consider another question:

QUESTION: What do you want to do in terms of a goal for VOLUME and TONE?

The reason I ask this question is that there are other things you can do to get different types of VOLUME and TONE . . .

For example, if you are handy with carpentry tools and know how to build plywood boxes, then if you want more VOLUME and deep bass, then you can build a larger plywood box to use as a loudspeaker cabinet for the two 12" loudspeakers of the Frontman, which you could wire in such a way that you can use one of the 12" loudspeakers separately as an 8-Ohm loudspeaker or can use both 12" loudspeakers wired in parallel as a 4-Ohm combination . . .

And the plywood cabinet could ported, which makes it a bass-reflex cabinet (in which case you can line the cabinet with one layer of fiberglass insulation but not pack the entire cabinet with fiberglass insulation), or it could not be ported, which makes it like the loudspeaker cabinet of a Fender "piggyback" unit (in which case you need to pack the cabinet with fiberglass insulation) . . .

Putting the two 12" Frontman loudspeakers in a larger fully enclosed plywood box (ported or not) will add a significant amount of deep bass to the TONE of the loudspeakers, and porting the plywood box will add more VOLUME to the deep bass . . .

There are other things you can do, but as noted in my previous post, the fact of the matter is that anything that is involved with guitars automatically costs more than stuff that is involved with public address (PA), which maps to an extension cabinet for a guitar being expensive but a PA cabinet being relatively inexpensive, which is based more on magic than logic . . .

Basically, nobody goes to a music store and says, "I want to sound like Elvis" . . .

Instead, they go to a music store and say, "I want to sound like Ace Frehley, Jimi Hendrix, Jimmy Page, or whatever" . . .

So, what happens is that if you want to sound like Elvis, the music store tells you that you need a PA cabinet, which they have on sale for $100, but if you want to sound like Jimmy Page, then they have a Super Deluxe "Stairway To Heaven" Marshall Stack for $7,500 . . .

In other words, you could go to the local building supply company and get about $250 of plywood, glue, screws, and fiberglass (if you already have the carpentry tools), and you could go to Radio Shack and get $50 of loudspeaker cable, output jacks, and so forth and so on, followed by building a nice loudspeaker cabinet . . .

Or you could get a PA loudspeaker cabinet and use it, which probably sounds better and is a lot louder, as well . . .

For example, you can get a pair of Kustom 15" PA cabinets with horns for $200 (US), and connect them to the Blues Deluxe Reissue with one PA cabinet connected to "Main Speaker" and the other connected to "External Speaker", and this will be louder than the Blues Deluxe Reissue 12" loudspeaker, and it will have considerably deeper bass TONE, as well as having brighter treble TONE, but it will sound different than the Blues Deluxe Reissue 12 loudspeaker, although since everything plug-in, you can use the Blues Deluxe Reissue either as it came from the factory or with one or both of the 15" PA cabinets . . .

Posted Image
Kustom KPC15 15" PA Speaker Cabinet with Horn Pair ~ $200 (US)

Another strategy is to use a pair of Kustom 12" PA cabinets with horns for $140 (US), which will have a different loudness and TONE (not quite so deep bass TONE but deeper bass TONE than the 12" loudspeaker in the Blues Deluxe Reissue) . . .

Posted Image
Kustom KPC12 12" PA SPeaker Cabinet with Horn Pair ~ $140 (US)

If you need more loudness and deeper bass and midrange TONE, then using either of these two PA cabinets will work nicely, since the general rule for deeper bass and midrange TONE is that the larger the loudspeakers and cabinets the better, where you could build larger plywood boxes and put the PA loudspeakers in them, and they would have even deeper bass and would be louder as well, if you ported the larger plywood boxes . . .

Part of the logic that determines pricing of music stuff is based on the general rule that the folks who do sound for bands know more about electromagnetism than guitar players, so music stores tend to make the guitar players pay more, mostly because guitar players tend to be a but clueless, while the folks who do sound for the band pay less and get better loudspeakers and cabinets, although there a few caveats . . .

A 50-watt vacuum-tube Marshall half-stack with a 4x12 Celestion "Greenback" loudspeaker cabinet costs the same no matter whether one is a guitar player or a sound engineer, and the fact of the matter is that it sounds great, as it should for about $3,000 or so . . .

So, as with everything, it depends on the specifics, but if you connect the Frontman to a pair of Kustom 15" PA cabinets with horns, which probably requires doing pulling the back cover of the PA cabinets and rewiring them so that they can be connected in parallel to get the desired 4-Ohm overall impedance, then they should be at least twice as loud as the pair of 12" loudspeakers in the Frontman, if not a lot louder, because 15" woofers move a lot of air for bass and horns do the same thing for treble . . .

And you can tailor the overall TONE with a few carefully selected effects pedals, so what one might call the "sound engineer" or "physics" perspective is to let the loudspeakers and cabinets simply be loudspeakers and cabinets, which saves a lot of money . . .

Then, you create the TONE with a combination of the guitar, effects pedals, and the amplifier, which if is the low-budget solution . . .

It all depends on what you need to do in terms of VOLUME, TONE, and so forth and so on . . .

For example, I have a 50-watt vacuum-tube Marshall amplifier and a full-stack where there are 4x12 Celestion "Greenback" loudspeakers in each of the two cabinets, and it is entirely too loud, even when I just use one 4x12 loudspeaker cabinet . . .

And considering that 40-watts (your Blues Deluxe Reissue output) is just 10-watts less than the 50-watt vacuum-tube Marshall amplifier, I know just by looking at photographs and reading the owner's manual that it will be nearly as loud, with the primary difference being the loudspeaker cabinets and the particular loudspeaker(s), where the Marshall half-stack will have a deeper bass and midrange TONE and a bit more loudness due to being a larger and fully-enclosed cabinet . . .

Depending on the local music store, you might be able to take your Blues Deluxe Reissue there and test it with a pair of Kustom 12" or 15" PA cabinets or some other type of external loudspeakers . . .

SUMMARY:

(1) I think that the Blues Deluxe Reissue is a high-quality "combo" amplifier, and it has unique TONE . . .

(2) You an use the Blues Deluxe Reissue to power the two 12" loudspeakers of the Frontman, but the Frontman amplifier needs to be powered-OFF . . .

(3) You could use one of the 12" loudspeakers of the Frontman as an external speaker for the Blues Deluxe Reissue by connecting it to the "External Speaker" jill, but the 12" loudspeaker of the Blues Deluxe Reissue needs to be connected to the "Main Speaker" jill . . .

(4) With their original loudspeakers connected as from the factory, you can use the send from one amplifier to do something with the other amplifier, and that might be productive . . .

(5) You can get some PA loudspeaker cabinets and use them with either of the two amplifiers to get considerably deeper bass and midrange TONE, as well as more loudness . . .

(6) If you do the connector (jack and jill) modification from my previous post, then the Frontman becomes a "piggyback" configuration, but there is a better way to do it if you want to use the Frontman amplifier separately, which is to have two jills--one for the amplifier output and the other to go to the loudspeakers (wired in parallel), where to run the Frontman in its original configuration you will need a short loudspeaker cable with jacks on each end, which you will plug into the output jill of the Frontman and to the input jill of the loudspeakers of the Frontman . . .

Remember that the basic rule is that amplifier loudspeaker outputs always go to loudspeakers and that when the power is ON for an amplifier the amplifier must be connected to a loudspeaker . . .

And a "combo" unit is just a "piggyback" unit in one box, so you can transform a "combo" unit into a "piggyback" unit by using jacks and jills so that you then can connect separately . . .

[IMPORTANT: There are loudspeaker cords, and there are guitar cords. These are very different, and you need to use a loudspeaker cord (bigger wires and not shielded) to connect a loudspeaker to the loudspeaker output of an amplifier. You should not use a guitar cord (which is a smaller inner wire with an outer shield wire that fully encloses the inner wire, although separated by a layer of insulation or whatever). If it goes to a loudspeaker,then use loudspeaker cord, but if it goes to a guitar, then use a guitar cord, which is a simple but very important rule . . . ]

One of these strategies should work, which is fabulous . . .

Fabulous! :)

P. S. If you are bored and have a bit of free time, watch the YouTube music video for the Surf Whammys hit song, "(I Want) Angela Gossow's Underpants (Ya-Ya-Ya)", since the more views it has the sooner it will go viral, where for reference "The Surf Whammys" is my pretend Rock and Roll band, and I play all the instruments and do all the singing and screaming, for sure . . . .

"(I Want) Angela Gossow's Underpants (Ya-Ya-Ya)" (The Surf Whammys) -- YouTube music video

For sure! :D

Edited by surfwhammy, 23 September 2010 - 08:01 PM.

The Surf Whammys

Sinkhorn's Dilemma: Every paradox has at least one non-trivial solution . . .

#5 ElevenBravo

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Posted 24 September 2010 - 07:46 AM




I recently purchased a marshall mg100hdfx headstock, and I currently don't have enough money to get a cab. I have no experience with half stacks so I was wondering if it would be possible to hook up my marshall head to my fender fronman 212 r and use that as a cab for the time being until i get enough money to buy a cab to go with the headstock, and if it is possible how would I go about doing it.


The "100" part of the name of your Marshall® amplifier refers to the amplifier (or "head") having a power output rating of 100 watts (100W) RMS (root mean square), and since the Fender® Frontman® 212R 100W 2x12 Guitar Combo Amp has two 12" loudspeaker that are rated at 100W RMS (as a pair, not separately), there is a way to use the Marshall amplifier to drive the Fender loudspeakers . . .


@surfwhammy - Simply an awesome response to jeff12623's question! I mean simply awesome, man. So awesome that I felt compelled to register for the forums so that I could post this note. I have an FM212R and recently bought a Blues Deluxe Reissue. I was considering buying the matching Fender tweed 1x12 extension cab (about $300), but figured what the h3ll, I already own a 2x12 inside the Frontman combo. Let's hear how it sounds and decide whether the matching 1x12 extension cab is worth the money (I'm thinking *not*) or whether my $$ is better spent replacing the speakers inside the Frontman. I have already used both of the amps in tandem by way of the pre-amp out of the Deluxe into the Pwr Amp In on the Frontman and it took a bit of tweaking but I got the pair sounding decent with each other, the Deluxe stacked on top of the Frontman. It does look like a stack o' sound for sure. However, I would rather have the Frontman speakers driven directly by the tube power in the Deluxe. My Google search led me to your reply post. I wasn't sure if the Frontman speakers were wired in series or parallel, but I suspected parallel.

Quick question: There are 2 speaker output "jills" on the Deluxe. One jill is for the Internal spkr, the other for an External spkr. If only Internal spkr is connected to the amp, then it's 8 ohms impedance. Internal plus External connected = 8 ohms output impedance to each spkr, Int and Ext. If Internal jill is "open" (must use a dummy jack though) and only External has a load (such as from the Frontman), then External jill rates at 4 ohms impedance. Since the method you suggested in your post would represent 4 ohm impedence from the Frontman, should I be concerned about running the Deluxe amp with an 8 ohm load from the Internal spkr and a 4 ohm load from the Frontman simultaneously? Should be no problems to connect the Frontman by itself without the Internal spkr connected in the Deluxe because there is a 4 ohm to 4 ohm impedance match. It would only be a concern if the speaker cab impedence were *lower* than the output impedence from the amp, right? Such as 4 ohm output impedence from the amp into a 2 ohms impedence load from the speakers. Does this make sense? I just don't want to hurt my Deluxe amp through impedence mismatching.

Thanks in advance for any and all advise or cautions. I'm going to stop by the electronics shop tonight and get the connectors I need to start wiring up the Frontman.

Cheers,

~ Johnny
(aka ElevenBravo)


Welcome to GuitarZone! And I am glad you found the previous information helpful! :)

...
P. S. If you are bored and have a bit of free time, watch the YouTube music video for the Surf Whammys hit song, "(I Want) Angela Gossow's Underpants (Ya-Ya-Ya)", since the more views it has the sooner it will go viral, where for reference "The Surf Whammys" is my pretend Rock and Roll band, and I play all the instruments and do all the singing and screaming, for sure . . . .

"(I Want) Angela Gossow's Underpants (Ya-Ya-Ya)" (The Surf Whammys) -- YouTube music video

For sure! :D


Wow again! Excellent information, surfwhammy and LOVE the video (I want her underpants too :) Much of what you so eloquently author here should be compiled into a stickie for others that have similar questions about signal chain and impedance matching. Great stuff!

Re: Your volume and tone question... the answer is I don't know. At this point, I'm experimenting with all of my equipment in order to understand what different combinations are possible and what they sound like. I have no idea of what my ultimate tone goal is. I will encounter great sounds along the way and probably a bunch of not-so-great sounding configurations. It's the journey and the discovery that interests me, not so much the destination if there is one. Re: Fender Deluxe and Frontman piggybacked, my question duly answered - I won't present a 4 ohm speaker load to the Deluxe power amp output if it is configured to expect an 8 ohm or greater impedance.

Rock on wit yer bad self,

~ Johnny

#6 surfwhammy

surfwhammy
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Posted 24 September 2010 - 09:43 AM

Wow again! Excellent information, surfwhammy and LOVE the video (I want her underpants too :) Much of what you so eloquently author here should be compiled into a stickie for others that have similar questions about signal chain and impedance matching. Great stuff!

Re: Your volume and tone question... the answer is I don't know. At this point, I'm experimenting with all of my equipment in order to understand what different combinations are possible and what they sound like. I have no idea of what my ultimate tone goal is. I will encounter great sounds along the way and probably a bunch of not-so-great sounding configurations. It's the journey and the discovery that interests me, not so much the destination if there is one. Re: Fender Deluxe and Frontman piggybacked, my question duly answered - I won't present a 4 ohm speaker load to the Deluxe power amp output if it is configured to expect an 8 ohm or greater impedance.

Rock on wit yer bad self,

~ Johnny


Glad you enjoyed the song!
:)

I was in a strange mood on New Year's Day 2010, and the Angela Gossow's Underpants song appeared, so I recorded it and then sometime later decided to do a YouTube music video for it . . .

Since then I have decided to explore the idea of doing an album of songs about ladies underpants, with the working title "Electric Underpants™", and more recently I am having a bit of FUN with a parody of "Bad Romance" (Lady Gaga), which at some point will mention something about her underpants, perhaps in some of the backup harmony vocals, for sure . . .

[NOTE: This is a headphone mix, and it does not have the lead guitar solo, but so what . . . ]

"I'm Going Goo-Goo Over Ga-Ga" (The Surf Whammys) -- Basic Rhythm Section and Lead Vocals -- MP3 (286-kbps [VBR], 9.5MB, approximately 4 minutes and 30 seconds)

For sure!

If you are handy with carpentry tools or know someone who can help you with a plywood project, there is something you can do based on one of the more fascinating rules of acoustic physics, which is that bass and midrange frequencies do better in larger cabinets . . .

Both of your "combo" amplifiers have open backs, which is done primarily for two reasons:

(1) It helps to provide ventilation for the various electrical components (which is particularly important for vacuum tubes) . . .

(2) It reduces the overall weight of the unit . . .

From the perspective of sound reinforcement, which in some respects is more of an audiophile aspect and is devoted to achieving optimal high-fidelity, the goal is a flat frequency response with no distortion, which can appear to be a bit counterproductive for purposes of TONE in some styles of electric guitar, but it is counterproductive only when you consider just part of the overall equation, which can be a bit confusing at first . . .

When you switch focus to sound reinforcement, the components are separated a bit differently, where for example preamplifiers are kept separate from power amplifiers, and woofers (a.k.a., "loudspeakers") are kept separate from midrange horns and tweeters . . .

And what in the electric guitar, bass, and keyboard universe is a "preamplifier" becomes in the sound reinforcement universe something called a "mixer", where in a simplistic way, a "mixer" is a sophisticated "preamplifier", complete with volume controls ("sliders"), tone controls (typically separated into bass, midrange, and treble), elaborate sends and returns, controls for panning, controls for adjusting various external effects, and so forth and so on . . .

The output of the "mixer" is sent to power amplifiers, and the output of power amplifiers drive the various loudspeakers, midrange horns, and tweeters based on special components that separate low frequencies from midrange and high frequencies . . .

One of the things you discover after working with sound reinforcement systems for a while is the fact (as noted) that low frequencies (bass) require larger cabinets and larger loudspeakers, but this general rule has some useful variations, and one of them is that virtually every loudspeaker will sound better in terms of bass response when it is moved from a smaller cabinet to a larger cabinet, so long as its current cabinet is smaller than the optimal size for the particular loudspeaker . . .

For example, consider that you have a 6" by 6" by 10" bookshelf speaker system that has a 4" diameter loudspeaker . . .

If you build a plywood box perhaps 2' by 2' by 3' and mount the 4" loudspeaker in this new plywood cabinet (which needs to be fully enclosed) and then line the interior with fiberglass insulation, followed by cutting a tiny port (perhaps 2" by 8") somewhere below the circular hole onto which you mount the 4" loudspeaker, then it is quite amazing how much better the 4" loudspeaker sounds . . .

It will have greatly improved deep bass, and it will be louder, as well, which overall maps to its having a "big" sound that is better in every respect . . .

If the bookshelf speaker has a tweeter, you can mount the tweeter in the same cabinet, and it will work just as well, although with little difference, since the larger volume plywood cabinet just makes the bass and midrange work better . . .

And you can do something similar with a "combo" amplifier for an electric guitar, where the general idea is to design the plywood box in such a way that it does not require making any changes to the "combo" amplifier . . .

Picture in your mind a plywood box that is one foot wider than your "combo" amplifier and perhaps two feet taller, as well as being two feet longer from front to back . . .

Then, imagine that you modify the plywood box so that it has a shelf at the top middle onto which you can set your "combo" amplifier, such that the top of the "combo" amplifier extends above the top of the plywood box so that it is easy to get to the power cord and any controls or whatever on the back top of the "combo" amplifier . . .

This cutout "shelf" will have a bottom onto which the "combo" amplifier sits, and it will have sides, as well, but it will not have a back, so what happens is that when you set the "combo" amplifier onto the cutout shelf, the lower perhaps two-thirds of the back of the "combo" amplifier will be in front of a similarly sized opening in the plywood box . . .

Then on the lower front of the plywood box, you cut a port that is perhaps 6" by the whatever is the width of the "combo" amplifier, and you line the inside walls of the plywood box with fiberglass insulation, which can be purchased in compacted but still porous sheets . . .

Since the back of the "combo" amplifier is open, when the loudspeakers move backward they push air into the plywood box via the opening at the back of the "shelf", and this transforms the entire thing ("combo" amplifier and plywood box) into a bass-reflex cabinet . . .

Posted Image
Bass Reflex Cabinet with Loudspeaker

Bass Reflex Loudspeaker System (wikipedia)

The result will be that the "combo" amplifier will have deep bass and improved midrange response, as well as greater potential loudness, which makes it an interesting experiment if you are handy with carpentry tools or have the ability to have a cabinet maker do the work . . .

It might take a few days to construct the plywood box, and the various materials might cost $150 to $200, since you will want to use cabinet-grade plywood, but the result can be spectacular, depending on whether you want better deep bass and midrange . . .

Another useful bit of information is that in professional sound reinforcement systems, the cross-over point for bass and midrange versus treble tends to be no higher than 500-Hz (where "Hz" maps to cycles per second), so everything below 500-Hz goes to the woofers (or big paper-cone loudspeakers) and everything 500-Hz or higher goes to horns (upper midrange and high frequency or treble) . . .

On a guitar at standard tuning based on the reference of Concert A (440-Hz), the A played at the 5th fret of the high-pitch "e" string will be 440-Hz, which is below 500-Hz, obviously . . .

In other words, the fundamental frequencies of the notes on a guitar at standard tuning respective to Concert A range from 82.4-Hz for the open low-pitch "E" string to 440-Hz at the 5th fret of the high-pitch "e" string, and these are all considered to be bass and low-midrange notes . . .

The overtones and harmonics are higher, of course, but the important bit of information is that guitar is a lower range instrument, and lower range instruments benefit from have volume in terms of physical space, which is one of the reasons that a 50-watt vacuum-tube Marshall half-stack with 4x12 Celestion "Greenback" loudspeakers has such a stellar range of TONE . . .

The loudspeaker cabinet is reasonably "big", and it has heavy plywood sides, front, and back, all of which combine to make it possible for the fundamental frequencies of the guitar strings to resonate and to be heard as they natural occur . . .

If you remove the back cover of a Marshall half-stack 4x12 cabinet, it will change the overall TONE dramatically in a way that not the least bit good, where the deep bass and punch simply vanish into thin air, which for all practical purposes is the primary problem with open-back "combo" amplifiers . . .

I have a Fender Custom Shop Dual Professional, which basically is a 100-watt Fender Twin amplifier with a spring reverb tank and some additional bells and whistles, and it has great TONE, but it can have even better TONE by doing the custom plywood box thing . . .

This is an interesting experiment, but whether it makes any practical sense is another matter, since for about the same cost, you could get a pair of Kustom 15" PA speaker systems, so it depends on what you want to do, but it is a great way to reveal the deep bass and punch of the Blues Deluxe Reissue "combo" amplifier, where the general idea is to provide approximately 12 cubic feet of additional fully-enclosed but ported space for the single 12" loudspeaker . . .

The deep bass and punch is there, but the open-back cabinet design hides it, which can be fine if you like the TONE the way it is . . .

The goal here is to provide some ideas of things that you can do to explore the tonal possibilities . . .

Another way to get a sense of how the custom plywood bass-reflex box works is to use connect a Fender "piggyback" loudspeaker cabinet to the "Main Speaker" or "External Speaker" jill of the Blues Deluxe Reissue amplifier, although most Fender "piggyback" loudspeaker and Marshall 4x12 loudspeaker cabinets are not ported . . .

It is one thing to tell someone that putting a 4" loudspeaker in a big plywood box will reveal deep bass (which it will), but hearing it is the proof, and it usually maps to having an epiphany regarding the way low frequencies work . . .

For example, one usually can hear a car audio system that has a high-powered subwoofer a block or two away, and the reason is that low bass notes have wave lengths ranging from 16 to 32 feet, which maps to low bass being able to travel easily through walls, houses, trees, air, shrubbery, and just about everything . . .

So, while you only hear the midrange and treble when the car is very close, you hear the low bass from a block or more (several hundred feet or more), and the subwoofer stuff actually vibrates the walls of houses, which among other things is one of the reasons that I fully floated the floor of the sound isolation studio, which additionally is a room within a room within a room, which makes it extraordinarily quiet and blocks nearly all the outside noise, which is fabulous . . .

Fabulous! :)

Edited by surfwhammy, 24 September 2010 - 09:56 AM.

The Surf Whammys

Sinkhorn's Dilemma: Every paradox has at least one non-trivial solution . . .



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