I recently had Kyle Takenaga modify my preamp/processor. You can read my A'gon review here. I've been very pleased with the improvements, which include increased resolution along with a greater sense of relaxation.
Kyle was very responsive both in emails and phone calls. And he was not the least bit secretive about his methods or parts, which was an important consideration for me.
I can't comment on this, as I only had Kyle modify a single piece of equipment. A conversation with him about your preamp might answer this question for you.
Sounds like there are other good options as well. Good luck.
Bryon
I would like to talk with someone who is well regarded not only for the quality of their work but also for their customer service...
Kyle was very responsive both in emails and phone calls. And he was not the least bit secretive about his methods or parts, which was an important consideration for me.
...and who has enough experience and expertise to assess each piece on an individual basis, and not simply apply the same bag of tricks to everything they touch.
I can't comment on this, as I only had Kyle modify a single piece of equipment. A conversation with him about your preamp might answer this question for you.
Sounds like there are other good options as well. Good luck.
Bryon