mods for Adcom GFP-750

Contact Stan Warren at (541)344-3696. He does mods the the Adcom 5802 which make it a giant killer. I have had Stan mod a Pioneer 525 DVD player and have bought his Single DACT passive pre-amp. Both units are incredible. Stan is also great to deal with.

I'd like to offer another point of view, and suggest that
your plan to modify the Adcom GTP-750, and maybe the 5802, is not well considered. I've been an audiophile for 40 some years, and have built my own gear from kits, and also done mod's (such as the DIY version of Musical Concepts mods for the Hafler 110 preamp and the 220 amp). I have yet to find a mod that is an improvement over the original product. Think about this: if a different circuit, power supply, etc., provided better sound and was cost effective, why didn't the manufacturer simply design it that way from the beginning? Mods are rarely cost effective -- a lot of money for minimal difference. Infact, I would almost suggest that mods are rarely better, simply different. If what you want is a different sound, then I recommend selling the preamp, amp, etc., that you have and buy something else. Finally, once you modify a unit you have effectively reduced its value to other potential buyers, and voided the manufacturer's warranty. My best intentioned advice here is to rethink mods to your Adcom gear. Both units have gotten very favorable reviews/ratings from several high-end audio mags, so I doubt you will improve on the sound by "modding" them.

As someone that makes their living by "modding" electronic components, i would COMPLETELY disagree with Sd's comments. Manufacturers build their products to meet specific specifications and price points. Keep in mind that adding one dollar to production costs equates to AT LEAST a 4 dollar increase in retail price and sometimes as much as 8 dollars. This means that they tend to use cheaper parts that will get the job done in order to keep the cost down as much as possible. As long as the unit will meet spec, survive the warranty period with minimal problems and draw in customers, that is pretty much all that they are worried about. Since most companies, especially those that produce "reasonably priced gear", think that wire is wire, resistors are resistors, caps are caps, etc... they use what they can get at the best prices with good reliability. On top of this, they tend to be conservative when it comes to really "fine tuning" the circuitry for best performance. Keeping the bias down reduces heat, power consumption, reduces production costs due to the need for less heat-sinking material, increases lifespan and reliability and helps them to easily surpass the warranty period. On top of that, they will tend to make use of larger amounts of negative feedback than what is really needed to get the job done. This is done because it makes the amp look better under test conditions and reduces distortion in terms of "paper specs". Since most of the people that are buying "affordable" gear are still quite "spec oriented", being able to print "pretty figures" is still quite important to manufacturers in terms of a marketing tool. They do this even though most all designers agree that negative feedback iin quantity is a BAD thing in terms of sonics. I could go on and on, but i think you get the point. Mods CAN be QUITE succesful if carefully thought out and well executed. If the basic circuitry was "as good as it gets", manufacturers would not be able to "upgrade" them and produce new models that DO perform better. "Tweaking" not only "fine tunes" the unit, it helps to advance the state of the art when done correctly. "Mass production" simply means "making as many units for the highest profit margin". It does not mean "quality" in most instances. Sean
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Sean: your points are fair, although I still believe, based on my own experience over a lengthy period, that major mods do not make good sense. The only mods I have ever heard that seemed worth the cost were the units from Audio by van Alstine. His "mods", however, are actually complete rebuilds using the chassis, power supplies, and maybe some of the internal circuitry. I personally think that any mod that costs more than 20% of the original purchase price is not cost effective, particularly if the owner plans to sell the unit at some future time.