Mac Amps

These can be “touchy” situations if the customer decides to have the amp returned, or partially returned to its previous (or alternate) specs. You can’t expect this to be done at no additional charge.

I should hope that this goes without saying, but I will always hesitate doing some modifications that will permanently de-value an otherwise vintage unit (although the term vintage is quite over-used these days. I have to laugh when someone refers to something that was made in the 80’s as vintage. I guess I’m showing my age.), then again, there have been many amps of vintage origin, that have since been subject to such things as: extensive “road” use, flood damage, previous alterations and/or “hack” work, aesthetic alterations of one form or another, or just general negligence, that have all ready “de-valued” the amp, and any further alterations would be of no consequence.

Most of the examples of mod work I have referred to herein have been with respect to Fenders. Over the years I have seen more Fenders than other makes (a few thousand actually) due to the fact that the Fenders are more prevalent than any other make, at least here in the states.
There are certainly various other mods that will cater more to Marshalls, and other British “stack” genre amps, such as Master volumes, power attenuation switches, and the like.

The bottom line with modification work, is to be certain that the customer receives the desired results. I’ll always want to point out possible “shortcomings” with some (such as the resulting “processed” sound that amps will have when a master volume is being used at very low settings for lower volume “break-up”).

Custom modification work comes in many forms. For some, changing the bias adjustment in an older Fender, for example, from a “balance” configuration, into a bias voltage adjustment set-up, would be interpreted as a “Mod” (I, personally think of it as a minor “tweak”, but that’s just me). Then again, my method of “Blackfacing” a silverface era Fender (refer to my “Blackfacing” page), is virtually re-building the amp.

[BTW, here we’re pretty much strictly talking about tube amps (NOTE: I’m not from the U.K., so I don’t refer to them as “valves”. ‘Sorry if that offends anyone out there).]
There are probably thousands of possible changes that can be made to guitar/instrument amps. Some can be: “the cat’s meow” for one player, but a: “Oh no! My amp’s been ruined!!”, for another.

Various other factors also certainly need to be taken into account, such as: the type(s) of guitar/pick-ups the owner uses; the type(s) of speaker(s) the amp is being used with; the style of speaker cabinet (open back vs. sealed); what effects [if any] the owner uses; what type(s) of music is it being used for; how “seasoned” the owner/player is (i.e. Does he/she REALLY know the sound they’re trying to get, or do they just have “far-fetched” ideas that MAY not be realistic); and of course, the personal playing technique of the individual.

There are also numerous internet sites that advertise various custom design changes for particular models. I always try to be open minded when my clients refer to these sites for work that they desire to have done. Many of the changes I will be familiar with, but there will always be some that I won’t be able to foresee how worthwhile the outcome will be for my client, this is certainly true for the more extensive changes. Once again, I always try to be accommodating, but I surely can’t be responsible for an undesired outcome resulting from someone else’s modifications.