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HELP with a Vintage Amp that's dead...

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  • HELP with a Vintage Amp that's dead...

    Here's some pix of my old vintage Ace Tone Duetto amp - circa 1963 I believe from studying the history... played like BUTTER until this afternoon when suddenly had some noises - then SILENCE. Tubes are all lit up fine? The Speaker has a transformer on it (?) I'm NOT an electronics type although I do electrical (110/220). I do have an ohm meter...

    Where do I get a transformer like the one shown? Is that it? I'm reading some weird voltages (set my meter on AC - 110) on the 3 incoming wires but reading nothing on the 2 going to the speaker(?) What should I be reading?

    The Ace Tone came almost MINT (Ebay deal a year or so ago). The only thing not working was the TREBLE input on the front. I figured screw-it. While checking "her" over I discovered there's a double fuse holder - 1 was missing a fuse... I figured that was the TREBLE channel problem - no fuse. I checked my fuse and it read continuity so I tried using tin-foil on the empty slot (I know I'm an idiot 'eh) and made a fuse - turned it on - NOTHING - no light - NOTHING - no noise either... I removed the tin-foil and still nothing - checked the good fuse and now it's dead - no continuity...

    So had to use tin-foil now to check it out. I'll get a fuse (what size? can't read anything on it?). But why no sound? Is it the trannie on the speaker? I have 2 amp techs close by - but both charge a lot and both say 2-3 weeks backlog... fixin' to email a guy advertising on Craigslist here and he says $35 per hour so maybe he's a bit cheaper... but I'd like to figure this out and save the money 'eh.

    The Ace Tone is whisper quiet - no hums or issues - and when cranked up (she's a 15-watt I'm guessing) IT SOUNDS LIKE A BLOODY PLEXI The Tremelo and Reverb all work fine too so shes worth fixing. I have other vintage tubers and they all sound good but this baby looks new and is quiet as a mouse and worth fixin'. HELP!







    There is nothing as fine as a vintage tube amp - and nothing sweeter than an old dude pushin' it hard...

  • #2
    First, get that tin foil out of there. It may already have killed both your power transformer and output transformer.

    First, go read the "Tube Amp Debugging Page" at geofex.com.

    Second, while you're doing those checks, make yourself a light bulb limiter. As an electrically-savvy guy, this should be easy. Get a metal junction box, a duplex outlet and an extension cord. Install the duplex in the box, and wire the two outlets with the hot wire of one going to the cold wire of the other by breaking off the tabs and using wires. Hot from the cut-off extension cord and cold from the extension cord go to the free hot and cold terminals, and ground goes everywhere ground always gos. This puts both outlets in series and lets you plug in a light bulb lamp in series with your amp. The bulb will prevent the amp from eating fuses while you do your work and will act as a visual indictor - full brightness is a short in the amp, dim is amp working ok-ishly.

    Pop back where when you've done those.
    Amazing!! Who would ever have guessed that someone who villified the evil rich people would begin happily accepting their millions in speaking fees!

    Oh, wait! That sounds familiar, somehow.

    Comment


    • #3
      draw a picture to show where each wire connects to the transformer
      they are all color coded. then you can disconnect the speaker side
      (two wires) at the transformer. these two wires that now only
      connect to the speaker can be touched to a 9 volt battery to test if
      the speaker is still working. this should produce a pop noise and
      the speaker will move in and out. if the speaker does not pop when
      connected to the battery, the speaker is burned out and is the first
      reason the fuse will blow.
      the next reason could be a shorted output transformer, check to see if the speaker is good, then move to the transformer. do you have an ohm meter?

      Comment


      • #4
        DO RG's debug page.

        Why do you think the transformer is bad? Just because it is visible? many many other things could cause loss of sound, including an open speaker. That battery test will tell you if it is bad.
        Education is what you're left with after you have forgotten what you have learned.

        Comment


        • #5
          Originally posted by Enzo View Post
          DO RG's debug page.

          Why do you think the transformer is bad? Just because it is visible? many many other things could cause loss of sound, including an open speaker. That battery test will tell you if it is bad.
          i think thats why i suggested the battery test, or maybe i'm hallucinating.
          i think this is why i suggested the transformer might be bad, i have repaired
          amps for 34 years, and that's one thing that goes wrong. i have repaired more guitar amps than most people have seen, hundreds and hundreds of them, even PVs. I have repaired and tuned Edgar Winter's keyboards, an idiot wouldn't be able to do that either.

          Comment


          • #6
            i think thats why i suggested the battery test, or maybe i'm hallucinating.
            It isn't about you, I was responding to Strangedogs

            I mentioned the battery test meaning the one you had just described. In other words I was agreeing with you that your test was a good idea. Y'see?

            I was asking HIM why HE thought the transformer was bad. He started the thread with that thought before you posted anything at all.

            I am glad you have repaired hundreds and hundreds of amps. If you have, then you know that the transformer is not the most likely failure in an amp. It is easy enough to check of course, but hardly the first thing on the list. More likely a wire came off on the way out to the transformer than the tranny itself, though anything is possible in this biz.

            And I fail to see what Edgar Winter's keyboards - or anyone else's for that matter - have to do with this man's amp repair.
            Education is what you're left with after you have forgotten what you have learned.

            Comment


            • #7
              I just happen to notice that the AL foil is also contacting the mounting screw for the dual fuse holder...since the aged amp is not of the 3prong variety,
              we're glad you didn't get between your guitar & ground ;-]

              Also, I would be very surprized if a shorted speaker in a tube amp would cause any fuse (other than a speaker fuse which I've never seen in a tube amp) to blow. Can you take a shot of the wiring side of the chassis for us? glen

              Comment


              • #8
                Originally posted by Mars Amp Repair View Post
                I just happen to notice that the AL foil is also contacting the mounting screw for the dual fuse holder...since the aged amp is not of the 3prong variety,
                we're glad you didn't get between your guitar & ground ;-]

                Also, I would be very surprized if a shorted speaker in a tube amp would cause any fuse (other than a speaker fuse which I've never seen in a tube amp) to blow. Can you take a shot of the wiring side of the chassis for us? glen
                shorted speaker no, but open speaker voice coil, yes.

                Comment


                • #9
                  Originally posted by mykey View Post
                  ... i have repaired amps for 34 years
                  I think that is open to debate, given how much you duck any real technical questions. You seem to blow a lot, but not to have much backup behind what you say.

                  Originally posted by mykey View Post
                  i have repaired more guitar amps than most people have seen, hundreds and hundreds of them, even PVs.
                  If that were true, and I believe it is an open issue, given your responses, pretty much everyone here has repaired hundreds and hundreds of them. If it's true, that makes you special HOW?

                  OK, math time again. Let's say for the sake of debate that "hundreds and hundreds" is 400. In 34 years, that's 12 amps a year. If we allow "hundreds and hundreds" to mean 800, that's only 24 a year, two a month.

                  Originally posted by mykey View Post
                  I have repaired and tuned Edgar Winter's keyboards, an idiot wouldn't be able to do that either.
                  I have some strong questions about that. It's pretty easy to say you did whatever. The proof is in the responses, and you're running several beers short of a six pack on those. Repaired Edgar's keyboards? Prove it. Then for extra points, tell us how working keyboards makes you an amp expert.

                  Originally posted by mykey View Post
                  the next reason could be a shorted output transformer, check to see if the speaker is good
                  What *exactly* is the reasoning that the transformer must be the next likely suspect, instead of some other part?

                  What test would one do after the battery pop test to start looking for what's broken?

                  Take your time, but the results will be graded.
                  Amazing!! Who would ever have guessed that someone who villified the evil rich people would begin happily accepting their millions in speaking fees!

                  Oh, wait! That sounds familiar, somehow.

                  Comment


                  • #10
                    Guys I didn't mean to start a war here 'eh... I'm gonna try 2 new tubes (the largest 2) this weekend - the local GC has some - also will get the inline fuse (slo-blo 1 amp) - will let ya' know what happens...

                    QUESTION:

                    I've been cheating a bit and using a tubescreamer as a "poor man's attenuator" - been cranking the amp to 10 - then setting the level way down (on the TS) to get FULL THROTTLE at low volumes... is this a bad thing to do as it's really not a power soak 'eh?

                    p.s. Johnny Winter I like Stole a lot of licks from Johnny and also "got him high" on Opium at the Atlanta Pop Festival in 1970 (long story). Edgar - MEH...
                    There is nothing as fine as a vintage tube amp - and nothing sweeter than an old dude pushin' it hard...

                    Comment


                    • #11
                      Sorry to catch you in the crossfire. You didn't start the war.

                      mykey's posts look good at first read, but some of the things he says don't seem reasonable to a number of experienced repairmen. He refuses to explain himself when questioned, only attacking his questioners on grounds that they are not progressive or interested in high performance amps.

                      So I've taken to asking him to explain what he says in detail. So far he has refused to explain himself at all, only blathering about how misunderstood he (and other big names!) is. That bodes ill for him knowing what he's talking about.

                      Be cautious of anyone who's giving technical advice - including me - if they won't explain why what they say works does work.
                      Amazing!! Who would ever have guessed that someone who villified the evil rich people would begin happily accepting their millions in speaking fees!

                      Oh, wait! That sounds familiar, somehow.

                      Comment


                      • #12
                        Originally posted by strangedogs View Post
                        QUESTION:

                        I've been cheating a bit and using a tubescreamer as a "poor man's attenuator" - been cranking the amp to 10 - then setting the level way down (on the TS) to get FULL THROTTLE at low volumes... is this a bad thing to do as it's really not a power soak 'eh?

                        p.s. Johnny Winter I like Stole a lot of licks from Johnny and also "got him high" on Opium at the Atlanta Pop Festival in 1970 (long story). Edgar - MEH...
                        Do you have any more of that opium ? That's probably why I screw so many post up Maybe Mykey can comment on that ?

                        The Tube screamer as the way it's used itself does no harm and it is actually in this case an attenuator but a different type. Kind of like the Seymour Duncan Convertible where the signal excursion is limited by the impedance of the plate on the PI when a 12AU7 is used. The tube screamer signal is limiting the amount of amplitude hitting the PI while the signal is bounded or compressed so to speak. The only bad thing is that the amp is at full power and when at full power more likely to arch or blow an OT if an open should occur while at full tilt. Your tubes are working harder causing the MTBF #'s on the tubes to go up especially in current production tubes so if one shorts the out-come could be more damaging than if at half power or less using preamp distortion instead of power tube distortion. If everything is in good condition no problems but keep your ears open for treble loss and volume drops as that's a sign the tubes are getting ready to go or a deep purple glow from the tubes. Blue glow is normal. FWIW I've been dealing with Enzo and RG for as long as oh, Mykeys been repairing amps and they have only provided me and several others here and everywhere with incredible & useful information so you can listen to what they say because they are the real deal !
                        KB

                        Comment


                        • #13
                          Thanks Amp Kat... wish I had some Opium but nowadays it's probably NOS. Amazing thing about these 2 old tubers I have is they have original 40 year old tubes in them! My Multivox has the original MULTIVOX labelled tubes - hate to change anything as the tone is so fine... My Acetone will receive new tubes this weekend (at least 2 of them) hopefully it won't dampen the sound I love so much. The old MultiVox has a PLEXI-like distortion that's thick and rich and because it's only 5-watts I can crank it fine in the house - the Ace Tone is what I usually use the TS on but when I carnk it up without it it has a "squawk" that's oh so nice but not as thick as the Multivox.

                          I had an Epi VJ for about a week and sold it as it couldn't compete with my Vintage babies...

                          I also have a couple SS amps that I use from time to time - 1 is an 80's ROLAND DAC with built-in effects and sounds quite wicked - has 4 small 6" transducers (might have neen a KB amp) that actually sounds very special...



                          Paid $60 for it on Ebay and was pleased with all the sounds possible from a 25 year old SS small amp like this... In the beginning of the 80's (or end of the 70's - can't remember) I traded a Fender Twin for a SUNN BETA LEAD as SS was starting to get big and the SUNN was an amazing amp ("With CMOS Technology" as the ads said). I was playing through a Marshall 100-watt Superlead but SS was so much more RELIABLE for gigs. Course it could never compete with my 1970 RED MARSHALL...

                          never heard a Marshall that sounded as good as that one... I had an old Fender 2/15 bassman bottom I put 2 EVM-200's in and it was literally AMAZING to hear. Never could find a matching RED bottom back then - then thanks to a terrible Heroin addiction I sold everything for peanuts... oh well...
                          Last edited by strangedogs; 06-23-2007, 06:04 PM.
                          There is nothing as fine as a vintage tube amp - and nothing sweeter than an old dude pushin' it hard...

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