tube preamp repair - southern NJ / Phila. area / Wilmington, DE area


Could any of you good folks recommend a good, reliable repair shop specializing in tube equipment repair/upgrading, in the greater Philadelphia, PA area?
The preamp in question belongs to a good friend who is not internet savvy. It is an old but excellent unit designed and built in Paoli, PA back in the 70s. It received a very good review by J. Gordon Holt when first introduced. I've spent many an evening enjoying classical music with his system and I must say the preamp is certainly worth getting repaired. It's a legacy piece.
The problem he is having is an occasional crackling sound from the right channel otherwise no distortion. We swapped the tubes left to right and vice versa but the problem stayed in the right channel. We suspect a capacitor as the culprit but he would really like to have the unit thoroughly gone over and upgraded by a competent technician. He is using an extra preamp of mine at this time.
Any suggestions?

Many thanks, Fred

fred_s
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Try contacting Bob Backert of RHB Sound Dezign. Bob has his own line of preamps now, through Backert Labs, but he still does repairs and mods on tube gear as far as I know. He is located in Churchville, PA.

http://www.rhbsound.com/contact/


If they cannot help, try DejaVu Audio in McClean Virginia - just outside DC. They make their own tube equipment using vintage parts. 
To ghosthouse, jmcgrogan2, and gsm18439:

Thanks to all three of you for your recommendations. I pulled up the contact info for all three companies and passed the info along to my friend. He will call them on Monday to discuss his problem.
He was amazed at this wonderful resource we have at our fingertips here on A/gon and passes on his thanks as well.

All the best, Fred