Why I don't do mods to old amps.
There's nothing that bothers me more than
a nice vintage amp that has been modded by a hacker. I've seen way too
many very nice and extremely valuable amps that were hacked to pieces mercilessly
by people that think they know more than the people that designed the amps.
I am under no impression that I'm as famous as the amps I work on.
I don't do mods other than to make the
amp more stable, safe, or to make it sound different without modifying
the circuit (ie different tubes). I do mod silverface Fenders back to blackface
quite often. This may be considered a misguided mod by some people, but
I consider it no more misguided than the things the propellerhead engineers
at "Fender" did in the CBS era (not a dig on all engineers by any stretch).
The blackface circuit sounds better.
I'm going to go through some mods that
people ask for and reasons why I think that they are misguided. Most of
these examples will be in the context of a Fender or Marshall because these
are the amps that I get asked about to mod more than others.
"I want a master volume
installed on my amp"
This mod is requested far too often. People
don't understand what a master volume does, but they ask for it anyway.
Amps that have a master volume to get distortion do so through preamp clipping.
This means that there was some sort of previous thought involved in shaping
the preamp gain and response to make it sound good with a master volume.
I get people asking me to add a master volume to a blackface Fender because
they want it to sound like it does cranked up, but at a lower volume. Guess
what folks? IT AIN'T HAPPENING. And I can't seem to convince people
of this. That nice distortion you get from your Super Reverb is due to
preamp, power amp, and speaker clipping, and other issues that happen only
when the amp is up loud all at the same time. Since the master volume removes
the latter two factors from the equation (the master volume is installed
right before the power section on most amps), how can you expect to get
that tone at lower volumes? Fender preamps don't clip all that nicely anyway
(brownface and later). Here's another example: I've had a few people that
own Deluxe Reverbs that say they love the sound of it cranked, and want
me to install a master volume on it to get it at lower volumes. The preamps
of the Deluxe Reverb and Twin Reverb look VERY similar. Do they sound the
same cranked up? No! So why assume that adding a master volume is going
to capture that sound? Here's another one: Fender installed master volumes
on later model silverface amps. Does it make it sound like a Marshall?
No! Let's get off the master volume ignorance! You can get closer with
a speaker load simulator (such as the THD Hot Plate, or Marshall Power
Brake), but that still neglects the speakers. Speakers do contribute to
the distortion characteristic.
Now, after all this, I'm sure people are
still going to ask me to install a master volume on their amp. My answer
is still "no". The reason why techs still do it is because misguided people
still believe that it will solve all their problems. There are a few isolated
circumstances where it will do something useful, but I'm not going to go
there right now.
"Make my Fender sound more
like a Marshall"
Uhhh, no. Why do you have a Fender if
you really want a Marshall tone? The subset of this one is "Make my Fender
have a footswitchable boost that makes it sound like a Marshall". That
ain't happening. There are a lot of "techs" out there that claim to have
done just this, yet I don't see them making a ton of cash because an amp
like this sure would be useful! And it's not going to happen within a Super
Reverb chassis! Marshall tone has a lot to do with the whole package. This
includes the circuit, tubes, speakers, cabinet, transformers... It goes
on and on. Changing one aspect of the amp to make it more Marshall like
isn't going to make it sound like a Marshall. Changing all of these things
to make it sound like a Marshall is an exercise in stupidity. Think about
what you will have when you are done. Parts and labor that are more expensive
than an entry level used Marshall, and a hack-butchered amp you have after
the mods is now worth nothing! A Fender is a Fender. If you want
a Marshall, go sell your Fender and buy one.
"Install EL34's in my Fender
to make it sound more like a Marshall"
This mentality follows the master volume
mentality fairly closely. EL34's do not make a Marshall. The first Marshalls
came with 6L6's! Marshalls from a few years ago came with Sovtek 5881's!
Do they still sound like Marshalls? Yes they do! So what makes anyone think
that EL34's in a Fender will make it sound more like a Marshall?
Another consideration: The EL34's draw
more than 50% more filament current than a 6L6GC. A 6L6 equipped Fender will usually
handle this fine, but I wouldn't guarantee that it would every time. Installing
these in a Deluxe Reverb or Princeton Reverb is an almost instant death
sentence. Don't do it!
EL34's will change the tone, and some people
may like what they do. However, I won't do it, so let's not talk about
"Install 6V6 tubes in my
Fender 6L6 amp"
This is an often asked for mod that I
won't do in any case. The current delivery in a 6L6 amp is too high for
the 6V6's to handle. If you look at plate voltages in a Twin Reverb vs.
a Deluxe Reverb, you will find that the Deluxe Reverb is higher in many
cases. So is the Princeton Reverb. These amps don't deliver the current
that the bigger amps do, so the tubes don't get worked as hard as the plate
voltage may suggest. If you install 6V6's in a Twin Reverb or Super Reverb,
you are actually unburdening the amp slightly (6V6's draw less current
than a 6L6), so there is even more current available to deliver. This means
that plate voltage will increase even more. The outcome? Your 6V6's will
be toast. They are not able to do what you are asking of them in a bigger
amp. They may work for a little while, but they won't last forever. Often
they will short dramatically and take other expensive parts with them.
I don't care what any other tech has written in any book about it. It's
a stupid thing to do and expect any longevity out of it. I won't do it
and please don't ask me to.
"Install more preamp tubes
in my Marshall ______ to give it more gain"
This is an 80's relic mod attitude. The
modded Marshall days are over, get over it! Many techs have made their
name modding old Marshall amps to give them more gain. That's all well
and good. But these days, there are a million amps that are made new that
give that same tone as the old modders were going after. Even Marshall
makes amps that are designed to emulate the old modded amps! It would be
more worthwhile to sell the amp you have while it's still worth something
and get one of these high gain amps. Examples of high gain amps that sound
pretty good and are hella cheap are Metaltronix, Peavey Ultra, Peavey 5150,
Carvin, Lee Jackson, Marshall JCM900, and countless
others. I wonder why these amps are so cheap now? All of these do the modded
Marshall thing better than modded Marshalls do themselves in my opionion.
"Install an effects loop
in my vintage Fender"
I will never understand the reason for
an effects loop in an old Fender. They are clean amps. If you need an effects
loop, then you are using the wrong effects or you think you need a loop
but you don't. Run effects through the input of the amp, plain and simple.
There are noted techs out there that install loops in vintage amps and
it pisses me off. If you really need it, then you are missing the point
of a vintage amp anyway. I'm sure there are circumstances where a loop
is warranted, but I'm not doing it. There are some companies now that have
loops that plug into a tube socket. I don't have any experience with them,
but this is a great idea if they work good. I think Magic Parts sells a
kit that does this. I will absolutely not install an effects loop in any
"Randy Smith (of Boogie)
and Jim Marshall started out modifying Fenders, don't you think you are
No, I don't. They started modding amps
back in the days when you couldn't go down to the store and buy the sound
you wanted. So these guys come in and set a new standard by modifying Fender
circuits. In Mesa's case, modifying them very heavily. Can I do this? Yes.
Am I going to do it? No. Go down to the store and buy an amp that sounds
like what you want. There's no use in hacking up an old amp that thousands
of people would want just the way it is. Leo Fender made these circuits
sound as good as they ever could have been, all I want to do is preserve
that. I'm not going to change the world by making a few mods to some amps.
It's too bad that there are a million techs in this country that think
they are the next Randy Smith. There are a million hacked up Fenders sitting
on a junk pile now to show how successful they've been.
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Last updated 7/12/01