Amp (Dis)repair or "My Expensive Education"

Discussion in 'Amp Central Station' started by dmarcus30, Nov 3, 2013.

  1. dmarcus30

    dmarcus30 Tele-Holic

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    Got a great deal on a Kendrick K Spot last year but it started making a roaring white noise when taken off standby. I took it to a well regarded local amp builder and repairman.
    Their wait times are about 2 weeks so 3 weeks later they call and say it needs a cap job, $350.

    I okayed the work which took 5 weeks. When I went to pick the amp up the white noise was gone but the amp had a harsh and buzzy quality that wasn't there before.
    We rolled various pre-amp tubes and settled on a low gain Sovtek as the best choice. I paid the bill and brought the amp home.
    I plugged it in the very next day and the white noise was back full force.

    Took it back (40 miles round trip each time) and we rolled tubes again. It was also discovered that a solder joint in the reverb tank wasn't just cold, it had never been soldered. The guy soldered it, we rolled tubes and got the amp to quiet down.

    You see the pattern here. It has been supposedly "fixed" 3 times now.
    Sure enough, it started roaring again every time I took it off standby.
    The amp is now back in the shop and I made him promise to call Kendrick and talk to Gerald personally as I had called him and he said he thought mine was an early one with a design that has since been improved.

    So, when I go pick up the amp this time it will be my FIFTH trip to the shop!

    I feel like I took my car to the shop for running rough and they replaced the engine before they even looked at the fuel filter. Doing a full cap job seems pretty drastic on an amp that is only a few years old.
    Regardless, the cap job DID NOT solve the noise problem so, clearly, the justification for such expensive work was wrong in the first place.

    I am dreading a showdown with this repairman as he can hold my amp hostage if he wants to.
    I believe he actually owes ME money at this point.

    Any thoughts on this situation?
     
  2. SoK66

    SoK66 Tele-Afflicted

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    Well, obviously your "tech" isn't. Doubtful he went through any diagnostic routine and I'd wager he has quite a few customers like you given his backlog. Before he ruins your amp quit while it's still in your hands.

    A couple questions: do you have a schematic of the amp from Kendrick? Have you spoken to Gerald? My hunch is you either have a bad socket connection that can be fixed with a simple clean & tension, or you just have a bad tube. You could also have an open or cracked plate resistor, but whatever, this is easy to pin down.

    Very hard to find competent techs these days. We had a guy here who was not only incompetent, but a thief as well. Was charging customers to replace perfectly good components in their vintage amps, then selling the pulls on EBay. Got caught and got the crap beaten out of himself. Out of biz.
     
  3. dmarcus30

    dmarcus30 Tele-Holic

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    Gerald Weber, to my knowledge, never surrenders a schematic. The cap job included basic service and the invoice says the tube sockets were cleaned. Doesn't mention re-tensioning.

    I think you may be right about a plate resistor. The amp puts 480 volts on the plates and that's factory spec.

    When I talked to Gerald he went into tech talk, of course, (I don't know electronics) and it has something to do with the "hot side of the standby switch" and the rectification.

    I'm pretty unhappy that the Kendrick caps got replaced with Spragues and it STILL makes noise.
    This guy actually started in the biz by attending one of Gerald's Amp Camps. He now has his own line of amps that are his take on blackface tone and they sound really good.

    Unfortunately,he also has an entrepreneur's ego as well. I don't relish having it out with him.

    He's already got my money, bucks I could barely afford to begin with. I had to borrow an amp for my last gig because the K Spot was still not predictably quiet.
     
  4. alnicopu

    alnicopu Friend of Leo's

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    Why don't you relish having it out with him? You're not paying him on the callbacks are you? Ego or not he's obviously just another incompetent person ripping people. I had a similar problem once, called the Better Business Bureau and the guy flipped out!!! Thats after i tried to reason with him on what it would take to make things right. Just like amp repair, I work in a tiny niche market for my side stuff. Believe me, in that small a market, one call as a complaint and I would be completely out of business overnight. If not, the word of mouth would put me out.

    As someone who had a very lucrative side business at one time I knew there would be problems I didn't fix the first time. I always went back, did whatever I had to to make it right, and never charged a dime for my callbacks on a related problem. Sometimes I lost money on that particular call but always kept them as a repeat customer for my efforts.
     
  5. ZZB3

    ZZB3 Tele-Holic

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    I wonder if he was the same tech I had sent my '65 Princeton to twice for a white noise problem that was never fixed. The third time he talked me over the phone and one of the tube sockets pins had a cold solder joint. Why was it not fixed when I had paid for that problem and shipping twice to and back again from his shop. The guy talked a good story but needless to say he will never see one of my amps again. I lost money on his BS. I wish you the best but find a different amp tech.
     
  6. Jim Dep

    Jim Dep Friend of Leo's

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    I'm sorry to hear about all this crap you are going through. He should be paying you for having to see a shrink too, just to address all the stress he's putting you through. That's horrible.

    Just curious, are you having to drive from Capitola up to San Jose? Hwy 17 is bad enough without being pissed.
     
  7. dmarcus30

    dmarcus30 Tele-Holic

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    No I am definitely NOT paying him on the callbacks and if he returned it to me perfectly repaired today I would still feel ripped off.
    I don't relish a confrontation because I might just blow my stack and I hate doing that. I do intend, though, to question his 'diagnostic process' that goes for top dollar and doesn't fix the problem.

    The only leverage I feel I might have is to call the BBB if necessary and/or give him a bad online review but so many online reviews look like bitter ranting from a weirdo.

    My dream amp has become a nightmare and I've spent a LOT of time and money. He has had the amp for 3 weeks now so he also does not do his "warranty work" in an honorable fashion. I should not have to go to the back of the service queue.

    I'm going to call him next week. The more I think about it the madder I get.
     
  8. alnicopu

    alnicopu Friend of Leo's

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    You can't let yourself get upset!!! As soon as that happens all communications cease and both sides dig in. Try to resolve the issue civilly with the goal in mind of getting the issue resolved. If that doesn't work, just say "fine, I guess I'll just have to escalate it". Tell him calling the BBB is your next alternative. Turn and calmly leave. Believe me, if you do this calmly and rationally he'll know you mean business. This guy is used to dealing with those who yell, scream and storm out. Then call the BBB, take him to small claims court and post what is then public record anyway and tell all your musician friends while you show them the court filing.

    I'm the easiest going guy you will ever meet and always try resolving issues so they end with a handshake. Having said that there are people out there who need to be taken down a notch.
     
  9. dmarcus30

    dmarcus30 Tele-Holic

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    Yep, Highway 17. He's out by the airport, Jim.
     
  10. dmarcus30

    dmarcus30 Tele-Holic

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    Good advice, alnicopu. I will give him a chance to make it right . If he doesn't, he will most definitely be outed.
     
  11. syrynx

    syrynx Tele-Afflicted

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    There is a very high probability that the white noise is being generated by a diode-- not a diode intentionally used as part of the amp circuit, but one unintentionally created by a poor contact. A cold (or completely unsoldered) joint can do that. But the intermittent nature of the white noise in your amp (goes away when tubes are replaced, but comes back) has me about 97% convinced that re-tensioning the tube sockets would fix it.

    Any unsoldered spring-tension connection in an amp (tube or solid-state) can become a point-contact diode over time, especially under the influence of heat, as metals oxidize. And there are dozens of spring-tension connections in an amp, including all input jacks, effects loop jacks, speaker jacks, tube (and transistor or IC) socket connections, reverb tank connections, potentiometer wipers, switches, and even fuse holders. Some of these (power and standby switches, speaker jacks, fuse holder) are much less likely to cause problems than others. But any such connection in the signal path, especially in the preamp and PI circuits, is quite literally a problem waiting to happen.

    A competent tech knows this, and checks for this sort of problem first, because fixing it is literally as easy as cleaning the contacts.

    I would really like to hear this tech explain why he thought a cap job would cure white noise, and I'd like to see his face as he attempted the explanation.
     
  12. Prairie Dawg

    Prairie Dawg Tele-Meister

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    What the competent technician does is set the amp up, and make it misbehave.

    Then, one gets the chassis out on the bench and finds the problem. That starts with mapping voltages.

    Is the problem related to the reverb? Does it do the same thing with the reverb disabled?
     
  13. telex76

    telex76 Doctor of Teleocity Ad Free Member

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    The tech obviousy doesn't know what he's doing.
    All you can do (if you want your amp back) is to try to get his lowest price and get your amp out of there.
    I wouldn't tell anybody to buy a high price amp unless they can work on it themselves,
    or they are independently wealthy.

    A trip to a shady, or "know nothing" tech (who thinks he knows it all) can put you in a
    a world of hurt.
     
  14. dmarcus30

    dmarcus30 Tele-Holic

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    PD, yes it does the white noise thing with the reverb disabled. What do you make of the fact that that noise went away temporarily by rolling 12ax7 preamp tubes and then the problem would reappear and what was a perfectly good tube had become microphonic?
     
  15. dmarcus30

    dmarcus30 Tele-Holic

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    Update: so after letting my still-malfunctioning K-Spot sit in my bedroom,only turning it on every couple weeks to run current through it, I found an amp tech who is very well regarded and still something of a secret locally.
    I took the amp to him and he has had it about 5 weeks which I don't mind. He found that the scammer did NOT clean the tube sockets or do any investigation as to why v1 kept eating tubes and why the amp is so noisy.
    The new tech, Erik Miller, who makes Euthymia fuzz pedals and repairs amps, actually DID clean the tube sockets and determined that v1 is receiving way too much current.
    He completely rebuilt everything on the board having to do with v1, the input jacks (also not cleaned by Amp Guru), and the amp is quiet and reliable now.
    Cost? A paltry $95!

    I can't wait to discuss this with The Guru and ask how he missed the obvious, lied about the work he says he did and, worst of all, insisted that his expensive cap job would fix all the problems. Cost? Around $400 including the two 12ax7s he sold me to "fix" the problem.And he had my amp for five months.
    Charlatan!
     
    Last edited: Jun 15, 2014
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