Adcom GFP-750 Modfication Question

Hey Lmack,
What all sonic improvements, top-end, midrange, and bottom-end did you gain after you had your former Adcom gfp-750 modified by Stan Warren at Supermods with the Black Gate caps? How substantial were the improvements? Is it worth the trouble of packing it up, sending it out, and paying $150.00 in your opinion? Please describe the sonic improvements in detail.

Black Gate caps give a warm liquidy feel to the midrange from the research Ive done and heard. Downside is break-in time. The consensus is it takes about 500-1000 hours for break-in. $150 may be worth the price if you use the Active Stage. I never needed to when I owned this unit awhile back, I was always in passive mode using all xlr's. ANd as they say, the best pre-amp is no preamp, and the closest to no preamp is a simple passive resistor with minimal traces design of Nelson Pass.

Daltonlanny,
Ritteri has succintly and accurately described the added "warm liquidity" to the midrange. Further, I heard less grain throughout, which resulted in a smoother, more relaxed presentation, especially top-end, with no loss of detail. While the Black Gates did take some time to break in, I started hearing obvious improvement within a week, and not much more improvement after two to three weeks--though I had my CD player running through it during much of this time, I would at least halve the break-in time Ritteri suggested to 250-500 hours. Yes, if I wasn't clear before: the $150, trouble, and wait was worth it. (Stan also did a great job handling the unit, leaving no external trace.) In my experience and for my listening preferences, there was "gain" and almost no loss in using the Black Gate active mode as compared to the renowned passive mode.

Michael Percy Audio sells Black Gates. If all you have to do is swap out cap's maybe you could do it yourself and not have to ship out the pre.
FWIW, I asked Adcom about swapping out components and they told me they use high quality components throughout and there was no need to upgrade anything.

Improvements are as described by Lmack and Ritteri. I would not recommend just swapping out the caps yourself since the values used by Stan are not exactly the same as used by the mfg. However, the improvements are noticible immediately and the unit will continue to improve. I almost always used it in active mode, which I believed provided more lifelike dynamics. The preamp was bettered overall (in my system) by a Muse Model 3 Signature. - Good luck.