Testimonials, Referrals, and Satisfied Clients
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Rob from New York
(actual email) "Rich, The amp showed up on Friday. This was a week after I found out Carvin started running a special on their factory blemished X100b amps for $469 free shipping with warranty! So, there I was, cranky and upset for the repair bill which I could have kicked in another $70 and bought a new amp. I slid the chassis into the cabinet, hooked up the reverb tank, plugged in the tubes and… MAGIC! The amp has never sounded better. Happy again! Making noise and loving it. The Marshall is now back in the corner where it belongs. So, what did I learn? Don’t do extensive rebuilds on cheap amps. I have enough invested in the Carvin I’m going to have to keep it another 10 years. (which is fine by me, it sounds fantastic) Next mission? The Fender Hot Rod Deville. To be continued… Thanks!!! Rob" - I offer this email, because Rob and I made the amp project a success, even though we had never met in person. Rob shipped me the chassis and several sets of tubes, with a no-power-on status. The Carvin had been sitting in storage for several years. Much more than a single issue, but grateful that the transformers were alright. If I may, here is the email I sent Rob beforehand: "50+ solder joints had to be reworked. There were two burnt traces, one of which had been poorly repaired. One trouble transformer lead attachment, two incorrect zener diode installs, and many short component leads that never reached the other side of the board. The preamp sockets were the most obvious. Overall, 3 hrs on the circuit to get us ready. We did a full Recap, at your request. 2.5 hours to replace the 6 filter caps, 4 bypass caps, and a half dozen other electrolytics on the board. The bypass caps were completely gone, leaking some of your power straight to ground (short)." Mike from Massachusetts (Contact Mike by request) In 2013, Mike requested that his 1960's Bogen be converted from a PA Amp to a Guitar Amp. Since this was a working amp, we brought the operating conditions back to spec, changed the input impedance to better capture the guitar's input signal, and gave it a 1/4"-to-1/2" mic style adapter. After 35 minutes of "sound testing" with his customized 1950's Regal Acoustic, we realized this jam session could go all night, and ended up laughing a lot. This past year, Mike has kept tabs on my Fender Blues Junior project, a complete rebuild with modifications. Found in a wet basement, this amp was in such poor condition, the cabinet had begun to rot. The chassis was still good, and the circuit board seemed to be in amazing shape. The welds, however, were cracking EVERYWHERE. 100% re-welded, new custom cabinet, and stock speaker. Once it was playing solid and true, the Blues Jr. accepted a Fromel tone kit upgrade, New filter capacitors were installed, including a larger main cap for tighter bass response and more. The reverb tank signal is notoriously noisy in this version (1995 dark/green board), so we moved the return lead so that it comes in at the second preamp tube, instead of the first. This really made the difference. Then, a bias adjustment pot was installed, so designed as to keep the stock bias when the pot is turned completely to one side. Vintage Sylvania EL84's transformed the "lightweight" sound into the Pink Floyd/Vintage Fender creaminess everyone feels when listening to a truly nice 60's/70's Fender Combo. This August, Mike bought the Blues Jr. That speaker should still be upgraded! Thanks Mike. Stephen from Massachusetts (Contact Stephen by request) Stephen is an excellent guitar player. Like most of us, a serious gear collector. Insatiable desire for the ultimate tone. With plenty of stage time and touring experience, Stephen brought me a Fender HotRod Deluxe, which had the stock speakers recently replaced with two Tone Tubby's. These are the larger ceramic magnet based speakers. The magnet and driver frame are so much larger than the stock speakers that the cone of the top-most speaker was in real danger of hitting the Output Transformer. We agreed to move the transformer 3/4" over, so it was out of the way. We then dealt with the tone of the amp, with its sharp ear piercing highs, and undefined lows. I fixed some poor factory joints (I follow MIL-SPEC soldering techniques for great sound and the highest reliability of my welds), changed a few parts, and when we were done, the highs were smooth and very musical, the mids were superior, and the lows were so articulate that complex chords could be played through the drive channel with every note sounding with its own place in the mix. This person is now a friend of mine, and has since dug through his attic to find projects in need of service and skill. I want you to be so thrilled, you will too! Chet from Massachusetts (Contact Chet by request) Chet introduced me to real Hi-Fi. Period. I had been working on Sony's, Sanyos, and every other major brand oddball that I could earn a living on. Classic Pioneers and Kenwoods with the wood exterior... those were my favorite. For a time. Actually, if you come across a Concord CR-200 or 250, that was MY AMP (in good working shape, and paired very nicely with a set of Acoustic Research monitors, medium sized room with plenty of mass). It wasn't until I met Chet, that I realized I had finally touched the tone and purity I had been looking for, my whole life. A DIY Nelson Pass Aleph J. Go look it up. Judiciously Class A, Huge Heat Sinks, and a dead silent noise floor - no master volume or tone control. It looked too easy, and I was surprised by how few parts went into such a fantastic performing amplifier! Needless to say, I have since sought to strike a better balance between technician and electrical engineer, to produce fantastic results whenever modifying an amplifier or building a customized one from scratch. So the Aleph J needed filter caps. The real story here is my testimony, and what I am fortunate to experience in the process of servicing audio equipment. Yours, and mine. I will be building an Aleph J for myself this winter. |
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Your project begins with a work order and finalizes with a record of the repair.
Biasing Tubes, so many ways. When they are properly biased, Better Dynamic Range, Longer Tube Life, Lower Distortion and a Higher Power Efficiency are all directly affected. Tone is also subjectively affected in a very noticeable way. So, it is best to approach biasing with an objective, and achieve the maximum Grin Factor.