mods for Adcom GFP-750

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.

Don't get me wrong, many mods are FOOLISH at best. Some are not cost effective and in many cases, actually degrade the performance of the unit. There there are the "cosmetic" upgrades, such as swapping one brand of gold plated copper binding posts for another brand of similar design but shaped differently, etc.. While "old golden ear" might be able to hear the difference between well designed components like these, i sure can't. Internal wiring and its routing is another story though. Things like this can make not only an audible difference, but also sometimes quite measurable differences. Sean
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Sean and SDcampell, thanks for your inputs. Its good to get constructive opposing views on the same subject. I'm considering modifying my cd player, Sony SCD-777ES SACD. What is the prefered way to route internal wire and which internal wire works best (Cardas, Wonder, Harmonic, Silver)? Was wondering in order of bag for the buck which components are usually better to replace in the power supply and analogue output stage circuit? Capacitors (Black Gates), Resistors (Caddock or Vishay), or diodes (Harris Fast Soft Recovery)? Does it pay to attach the deflex sheets to the top plate of the chassis? Since my power transformers are not shileded like the SCD-1, does it pay to buy the TI shielding and "apply it" to the transformers? Thanks in advance for your inputs. Mike