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  • #46
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ID:	131844 rhis one is easier to read
    PAP Trio 10/Voxativ & PAP Trio 15 Horn speakers, Ampsandsound Casablanca monoblocks, First Sound Audio Mark 3SI Paramount preamp,
    Mojo Audio Deja Vu server, Mojo Audio Mystique V3 DAC, The Linear Solution Ethernet Switch, Blue Jeans Ethernet cablling,
    Akiko Corelli, Custom power strip direct wired to panel with OFC copper wire. Inakustik Ref Air 2404 Speaker cable. Genesis and Inakustik NF2404 Air Interconnects. ADDPower Symphony and Electraclear.

    Comment


    • rbbert
      rbbert commented
      Editing a comment
      http://www.audiotubes.com/teledate.htm

    • Kingrex
      Kingrex commented
      Editing a comment
      I know Brent has fans, but the worst tubes I have gotten came from him. I sold my Airtight preamp because I thought the preamp had issues. It was a bunch of crappy microphonic tubes I got from him. I buy elsewhere now.

      I found amazing 12AX7 from another source. Best Siemens I have heard.

      His site is fairly informative.

    • rbbert
      rbbert commented
      Editing a comment
      I have nothing for or against Brent; I bought a pair of tubes from him I didn't like and he took them back, no questions asked, full refund including one-way shipping. His site simply has the most easily found reference for Telefunken date codes since the original document seems to have disappeared from the Web.

  • #47
    Lots of ideas posted.

    To not let the contributions go in vain, a list is needed on a what and how analysis by you to keep track of rooting out the culprit(s).

    Sometimes it can feel like the prize is in the jar of marbles, be patient, be disciplined be relentless, it’ll be there, found and addressed.
    Source Analog: Kuzma Stabi R with 4point 9 arm & Kuzma 40 Cartridge
    Source Digital: Aurender N10 | Brinkmann Nyquist MK II
    Amplification: Dan D’Agostino Momentum Pre Amp and Monos | Boulder Phono 508
    Speakers: Wilson Alexias
    Cabling: Nordost Valhalla 2/Odin: power, interconnects & speaker | Ansuz: C2 power & interconnect | Audioquest Diamond RJ45’s
    Power: Nordost QRT series | Furutech FP55SN cable from 20 Amp Breakers on grounded sub panel to Furutech GTX D NSF receptacle packages | Surge Guard at Main Panel | Keces P3 & P8 | ADD POWR series
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    • #48
      Rex to be clear if the amps are shorted at the input the both amps hum as we discussed. This leaves tubes or amps them selves. Your speakers are about 94db but the hum is only 60 cycle and only heard in woofers. To me if it’s not the tubes alone it can be only 2 other reasons.
      1- the tubes relativity to the transformers meaning EMI
      2- the power supply has a high ripple

      If it was me I would contact the maker to discuss this issue and a possible fix for it.

      since it’s both amps this makes me feel I’m correct in my assessment.

      No hum if only output tubes used
      hum starts when Input and driver tubes are installed.
      you can try to lift the ground on one amp to see if it stops. I doubt unless the tube circuitry is leaking to ground. Just try one amp.
      after this if it still Hums it’s on the maker to resolve it. to me it’s a toss up but I’m leaning on tubes and Emi last is the psu

      Out of curiosity please use a dvm on mv AC setting amp on , inputs shorted and speakers connected. Take note of measurements. It will be in MV AC this voltage is why you hear hum. The higher the dB eff of speakers makes it more prone to hum. A low dB eff speaker needs a lot more voltage to allow us to hear the hum. all amps output some ripple and also dc too if not a transformer output type.
      please do this and post
      ty

      ps on tube life for me it’s half at best of what they claim. Anyone who has a spare set can hear it.
      analog stuff.
      otari mtr 10 2 track 1/4 made new by soren
      otari mtr 10 2 track 1/4 1/2 combo made new by soren
      sota sapphire used eminent tech ver 2 arm
      new sota nova table has magnetic levitation platter and full speed control and latest motor same arm as above
      thorens td124 sme ver 2 arm
      thorens td125 sme ver 2 arm
      kenwood direct drive sme ver 2 arm
      phono preamp Ml no 25 all re capped
      speakers cust infinity IRS V , new caps and LPS , magnets etc.
      mark levivson pre no 26 amps no 33
      digital three cust servers , win ser 2016 , AO
      Dacs lampi various

      Comment


      • #49
        Originally posted by Alrainbow View Post
        ...ps on tube life for me it’s half at best of what they claim. Anyone who has a spare set can hear it.
        I'm not sure what this statement means, or whether there is any data to support it. "What they claim" is pretty meaningless; who are "they", and why is "anyone who has a spare set" a better judge? For that matter, "they" and "anyone who has a spare set" are probably one and the same. It isn't as if there are current manufacturers of NOS tubes "claiming" anything about them.

        Modwright Oppo 205 full tube mod
        Pass Labs INT60
        Daedalus Audio Ulysses v.2
        REL S3
        Daedalus/Wywires and Acoustic Zen cables
        Torus IS5

        Comment


        • Kingrex
          Kingrex commented
          Editing a comment
          My preamp tubes with 6000 hours are fine. Swapping my spare set says so. But I would like a 3rd and maybe 4th set. I need maybe 20 years worth of tubes.

        • rbbert
          rbbert commented
          Editing a comment
          Which is part of my point. The comment about "10,000 hrs" for some NOS tube types (usually lower power pre-amp tubes conservatively driven) comes from users' experiences, not from any authoritative reference.

      • #50
        Originally posted by rbbert View Post

        I'm not sure what this statement means, or whether there is any data to support it. "What they claim" is pretty meaningless; who are "they", and why is "anyone who has a spare set" a better judge? For that matter, "they" and "anyone who has a spare set" are probably one and the same. It isn't as if there are current manufacturers of NOS tubes "claiming" anything about them.
        My claim is ears 👂 alone
        testing tubes is good but not definitive in the sound. You can’t measure tube burn in but we all hear it.
        analog stuff.
        otari mtr 10 2 track 1/4 made new by soren
        otari mtr 10 2 track 1/4 1/2 combo made new by soren
        sota sapphire used eminent tech ver 2 arm
        new sota nova table has magnetic levitation platter and full speed control and latest motor same arm as above
        thorens td124 sme ver 2 arm
        thorens td125 sme ver 2 arm
        kenwood direct drive sme ver 2 arm
        phono preamp Ml no 25 all re capped
        speakers cust infinity IRS V , new caps and LPS , magnets etc.
        mark levivson pre no 26 amps no 33
        digital three cust servers , win ser 2016 , AO
        Dacs lampi various

        Comment


        • #51
          Originally posted by Alrainbow View Post
          ...You can’t measure tube burn in but we all hear it.
          Really?? How do you know what you are hearing? More importantly, how do you determine when a tube is "burned in", especially with "NOS" tubes that usually have some unknown number of hours on them?

          Modwright Oppo 205 full tube mod
          Pass Labs INT60
          Daedalus Audio Ulysses v.2
          REL S3
          Daedalus/Wywires and Acoustic Zen cables
          Torus IS5

          Comment


          • #52
            Well, I fixed the humming issue. I chased it down to the amplifiers and finally faced the reality that the Ampsandsound Casablanca are quite noisy. So noisy they hum loud enough to disturb my wife while they are idling and she is watching TV. I guess I was being loyal to the gear. Now I'm kind of irritated with the whole situation and the frustration it has caused me. I had another SS amp in my system while the Casablanca were being repaired for an entirely different issue. The SS amp was darn quiet. Unfortunately I now need to seek out a better designed product that does not need to be sent for repairs twice in a year and a half. Maybe the time is now to try a decent SS amp. Per other threads of mine, I have had an interest in them for some time. The constant racket from the Casablanca is finally forcing me to action.
            PAP Trio 10/Voxativ & PAP Trio 15 Horn speakers, Ampsandsound Casablanca monoblocks, First Sound Audio Mark 3SI Paramount preamp,
            Mojo Audio Deja Vu server, Mojo Audio Mystique V3 DAC, The Linear Solution Ethernet Switch, Blue Jeans Ethernet cablling,
            Akiko Corelli, Custom power strip direct wired to panel with OFC copper wire. Inakustik Ref Air 2404 Speaker cable. Genesis and Inakustik NF2404 Air Interconnects. ADDPower Symphony and Electraclear.

            Comment


            • #53
              FWIW Al. The Circuit board does not allow for the installation of a filter cap on the PS to clean the hum. There is not enough room. I may investigate cutting the topplate and fitting them in. These amps have no resale value. Partly due to design issues and partly due to shipping denting one of the cases. The Ampsandsound woodworker sweated out the dent but refinished the amp in a different color. They don't match now. Another bummer.
              PAP Trio 10/Voxativ & PAP Trio 15 Horn speakers, Ampsandsound Casablanca monoblocks, First Sound Audio Mark 3SI Paramount preamp,
              Mojo Audio Deja Vu server, Mojo Audio Mystique V3 DAC, The Linear Solution Ethernet Switch, Blue Jeans Ethernet cablling,
              Akiko Corelli, Custom power strip direct wired to panel with OFC copper wire. Inakustik Ref Air 2404 Speaker cable. Genesis and Inakustik NF2404 Air Interconnects. ADDPower Symphony and Electraclear.

              Comment


              • #54
                It’s a sad thing but maybe time to move on.
                analog stuff.
                otari mtr 10 2 track 1/4 made new by soren
                otari mtr 10 2 track 1/4 1/2 combo made new by soren
                sota sapphire used eminent tech ver 2 arm
                new sota nova table has magnetic levitation platter and full speed control and latest motor same arm as above
                thorens td124 sme ver 2 arm
                thorens td125 sme ver 2 arm
                kenwood direct drive sme ver 2 arm
                phono preamp Ml no 25 all re capped
                speakers cust infinity IRS V , new caps and LPS , magnets etc.
                mark levivson pre no 26 amps no 33
                digital three cust servers , win ser 2016 , AO
                Dacs lampi various

                Comment


                • Kingrex
                  Kingrex commented
                  Editing a comment
                  Thanks for all your help Al. You know a hell of a lot about circuit design. The ampsandsound engineer agreed your suggestion just may work and quiet the noise, but putting long leads on the caps to get them from between the CB and top plate would negate their value. I may have my local guy show me where the PS really is and determine if I can hole saw a space in the top to fit them. I have to look over our text again. I think I have the link to the caps you think will work.

                  In the mean time I am looking at a Valvtec E2 SE. $4K.
                  http://www.10audio.com/valvet_e2-se.htm

                  I have been offered a Dartzeel 108 for 10K from a dealer. That is a hell of a deal. But I just spent $25K on furniture. I feel pretty tapped out.

              • #55
                Originally posted by Kingrex View Post
                The SS amp was darn quiet. Unfortunately I now need to seek out a better designed product that does not need to be sent for repairs twice in a year and a half. Maybe the time is now to try a decent SS amp.
                I would not be discouraged about tubes simply because you got an amplifier that was a dud. Tubes can and should be quiet enough that you can run them on horns; after all, that is what they were originally used on!

                I had a customer very recently that had one of our preamps and a set of amps made by a well-known solid state designer. He was getting a pretty loud hum with the combination. The preamp came back to us a couple of times but we found nothing wrong with it- finally I convinced him to send one of the amps and there was the hum, caused by a ground loop. Fortunately it was easy to diagnose what the bug was in the amp and now its pretty quiet. This and it still meets UL requirements and CE directives. Now he's sending the other channel.

                Not humming is a function of proper design and not a function of tube or solid state!

                Comment


                • #56
                  I'm actually talking to my local tech and Pat Hickman ow Wammerdyne amps. He said its probably a cheap PS. He makes a voltage regulated solid state power supply for his amps and says its like 115 db quiet. He has my speakers and assures they are dead quiet. He said he may be able to mod my amp and shut the noise down. But who knows the cost till he really sees them. FWIW- he also does repairs. Thats how he started. He use to work on my CJ amps.
                  PAP Trio 10/Voxativ & PAP Trio 15 Horn speakers, Ampsandsound Casablanca monoblocks, First Sound Audio Mark 3SI Paramount preamp,
                  Mojo Audio Deja Vu server, Mojo Audio Mystique V3 DAC, The Linear Solution Ethernet Switch, Blue Jeans Ethernet cablling,
                  Akiko Corelli, Custom power strip direct wired to panel with OFC copper wire. Inakustik Ref Air 2404 Speaker cable. Genesis and Inakustik NF2404 Air Interconnects. ADDPower Symphony and Electraclear.

                  Comment


                  • #57
                    A local tech, mostly a guitar amp repair guy thinks the noise is coming from my 12ax7. Since pulling the 12ax7 results in dead quiet, he says the noise starts there. Not the PS.
                    since I put these over my tube and they did nothing, he thinks the AC power on the 5 volt heater is leaking into the signal. He want to try putting 5 volt dc to my heater. Does this sound reasonable? Any other ideas.

                    Click image for larger version

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Views:	53
Size:	2.89 MB
ID:	132721
                    PAP Trio 10/Voxativ & PAP Trio 15 Horn speakers, Ampsandsound Casablanca monoblocks, First Sound Audio Mark 3SI Paramount preamp,
                    Mojo Audio Deja Vu server, Mojo Audio Mystique V3 DAC, The Linear Solution Ethernet Switch, Blue Jeans Ethernet cablling,
                    Akiko Corelli, Custom power strip direct wired to panel with OFC copper wire. Inakustik Ref Air 2404 Speaker cable. Genesis and Inakustik NF2404 Air Interconnects. ADDPower Symphony and Electraclear.

                    Comment


                    • #58
                      A scope will be useful. probe pre and post 12ax7 with and without test signal.
                      Regards,

                      Erik
                      http://solypsa.com
                      North American distributor for:
                      Sensitive Sound MC Cartridges
                      STST Turntables + Tonearms


                      Available for in home setup and calibration of fine turntable systems

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                      • #59
                        An more simple approach is a amp or preamp Inyo an amp snd use it as a signal tracer. reg dc on heaters output and gain stages are mostly dc to obtain a lower noise floor. I’m not a builder only a tweaker. are the other tube heaters ac as well ?
                        also if you remove one stage prior to output it would be silent just saying
                        analog stuff.
                        otari mtr 10 2 track 1/4 made new by soren
                        otari mtr 10 2 track 1/4 1/2 combo made new by soren
                        sota sapphire used eminent tech ver 2 arm
                        new sota nova table has magnetic levitation platter and full speed control and latest motor same arm as above
                        thorens td124 sme ver 2 arm
                        thorens td125 sme ver 2 arm
                        kenwood direct drive sme ver 2 arm
                        phono preamp Ml no 25 all re capped
                        speakers cust infinity IRS V , new caps and LPS , magnets etc.
                        mark levivson pre no 26 amps no 33
                        digital three cust servers , win ser 2016 , AO
                        Dacs lampi various

                        Comment


                        • Kingrex
                          Kingrex commented
                          Editing a comment
                          Not quite sure what you are saying but my amp is built on a $75 DIY Tube Circuit board. The heaters are AC off a CB. That may be where the noise is coming from. Or so my local guy thinks. He is suggesting we try putting DC to the heater as DC won't create 60 cycle hum. I was talking with him some more and he may be able to jerry rig a socket to socket and drive the heater with DC, then listen with headphone to see if the noise is diminished. If it is, he then needs to figure how to get DC past the CB AC pins. Who knows, maybe he will just drill it out and sleeve a DC heater to it. But that is step 2 provided 1 works.

                          Eriks idea is pretty good. Scope the signal. This guy has to have some tools. He has been doing this for 30 or so years. Quite a few bands have him tune stuff when in town.

                          I hope it works. I don't want to throw away $4,500. Or at least $3,500. Someone would be very happy to have these for $1,000. And then what????????? E Gads.

                      • #60
                        https://www.diyaudio.com/forums/tube...ers-ac-dc.html
                        read up Rex. AC is ok but and dc is too.
                        to make them dc is not to hard but I’m not sure of all the tubes need the same heater voltage current ? Also you need or should adjust each for bias as the heater voltage should vary this. I’m guessing but think so.
                        analog stuff.
                        otari mtr 10 2 track 1/4 made new by soren
                        otari mtr 10 2 track 1/4 1/2 combo made new by soren
                        sota sapphire used eminent tech ver 2 arm
                        new sota nova table has magnetic levitation platter and full speed control and latest motor same arm as above
                        thorens td124 sme ver 2 arm
                        thorens td125 sme ver 2 arm
                        kenwood direct drive sme ver 2 arm
                        phono preamp Ml no 25 all re capped
                        speakers cust infinity IRS V , new caps and LPS , magnets etc.
                        mark levivson pre no 26 amps no 33
                        digital three cust servers , win ser 2016 , AO
                        Dacs lampi various

                        Comment

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