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tube amp

  1. sae-7125

    heathkit w-5m renovations [boondoggle edition] quantum vacuum deep dive

    posting some basic notes and measurements (photo journal) for an ongoing project that will eventually have "edited highlights" posted in the season-2 bench thread (also ongoing) since season-1 has reached q&a mode. starting with a somewhat minimal familiarity in regards to "foundation era" tube...
    • sae-7125
    • Thread
    • 1940s/1950s tech david theodore nelson williamson heathkit irreplaceable history monaural output monophonic original design issues tube amp vintage time capsule w-5m
    • Replies: 345
    • Forum: DIY
  2. Mike244

    Model 500A with strange date

    In Friday I got Sansui 500A from Japan. From the information available on the web, it follows that they were produced in 1967-1969, but in this one all the Elco-caps have a date of 1975-1976, I am 100% sure that no one has ever touched this receiver with a soldering iron. Unfortunately, there is...
  3. gwendal

    kora 100 SB mono blocks help needed

    Hi I am deseperatly looking for the kora 100 sb mono blocks schematics or any technical documentation . Thanks in advance . All the best .
    • gwendal
    • Thread
    • kora mono blocks schematics needed tube amp
    • Replies: 4
    • Forum: Tube Audio
  4. ibm3270

    Help identifying P.A. tube amp

    Hello! The Borough in Donora is planning on bringing their antique Public Address system online for it's 125th Quasiquicentennial celebration. Numerous hours searching online has returned zero results with the manufacturer of their historical amp. Historically there was a Montgomery Ward in...
    • ibm3270
    • Thread
    • identify tube amp tube amp amplifier tube amp chassis
    • Replies: 13
    • Forum: Tube Audio
  5. goldencalves

    ARC SP-14 stopped turning on (did I fry my preamp?)

    Hi y'all, long-time forum lurker, first time poster. I very recently came into possession of an Audio Research SP14, in very good shape from a very reputable dealer (online, but with a high end brick and mortar store). Worked perfectly fine, sounded great on CD, but realized the phono out...
    • goldencalves
    • Thread
    • arc audio research audioresearch preamp sp14 tube amp
    • Replies: 5
    • Forum: DIY
  6. mcaddie7

    Silvertone 9250A Restoration

    I typically restore higher end audio but found this Silvertone upper section for $7 and couldn’t resist. It’s all in great shape, so was thinking of oiling up the mahogany cabinet, and quickly rewiring the tonearm and throwing in a cheap Stanton 500. Does anyone have any info / thoughts on...
  7. B

    Hard to find capacitors

    Hello. I’m looking for some hard to find replacement caps for out Kuba Carmen amp. Some I’ve found, right capacitance but higher voltage. I’ve heard that should be fine. Others I can’t find at all. Any suggestions? Picture for reference.
  8. T

    New to me help with H.H Scott LK-72 B

    I’ve been reading a lot and researching this group on this amp. Plan on doing most of the upgrades I’ve found people doing. But the amp I got has something different on it that no other has. I’m stilll a beginner in audio but what’s this rca bridge type thing running into the power block? I’ll...
  9. A

    Knight KA-55 thoughts?

    I currently have a NAD 7125, hooked up with an AR-XA and some KLH 22s on the way. There's a Knight KA-55 nearby on Facebook Marketplace for $250. I'm struggling to find any information about Knight amps besides people in the midst of restoration projects. What can anyone tell me about the...
    • ahh
    • Thread
    • knight tube amp
    • Replies: 10
    • Forum: Tube Audio
  10. K

    KLH 17 versus University LTV Medallion

    I have the opportunity to pick up locally a pair of KLH 17 or University LTV Medallion for the same price ($200), both in mint condition. The KLH was even recapped but I’m not sure if the University was recently serviced. The seller got them from a tech who said they didn’t need it and they do...
    • klaval
    • Thread
    • klh 17 magnavox sansui 5000x tube tube amp university medalion vintage speaker
    • Replies: 6
    • Forum: Speakers
  11. mcaddie7

    Realistic 40/a Tube Amp Restoration Help

    Hi all, Looking for a schematic for this amp if anyone has it. I have a beautiful Realistic 40/an amp that looks like it has never left a box(it has!) and the owner said it stopped working one day. I found one of the output tubes was blown. I ordered 4 new 6BQ5s and started with my simple...
    • mcaddie7
    • Thread
    • realistic realistic 40/a tube tube amp
    • Replies: 20
    • Forum: Tube Audio
  12. tlann

    HH Scott Stereomaster 340b — Service Advice

    I got a little carried away yesterday morning and accidentally won an auction for a Scott 340b with a nice wood case. I got it for a decent price but will have to pay for shipping — and I have no idea what shape the receiver is in, other than that it's cosmetically pretty good. Even if it starts...
    • tlann
    • Thread
    • hh scott repair repair advice scott scott 340b stereomaster stereomaster 340b tube tube amp
    • Replies: 14
    • Forum: Tube Audio
  13. tlann

    Dynaco SCA-35 Heat with Wood Case

    Hey everyone, I’d love to hear from anyone who has run a Dynaco SCA-35 with the Dynaco wood case that has the routed slots on top — that is, the Dynaco cab 1D. I’ve read some people speculating that the SCA-35 would get too hot in a wood case, but I would be curious to hear from anyone who has...
    • tlann
    • Thread
    • dynaco dynaco sca 35 overheat tube amp wood wood case
    • Replies: 22
    • Forum: Tube Audio
  14. R

    Help identifying tube amp

    Hi, i'm about to buy this diy amp, and since it has no labels (gain, volume, e.t.c), in order to check it, i tried to find what amp it was based on, but didn't found similar one. Does it resemble any amplifier you know ? And any advice on how to check it will be appreciated. These are all the...
  15. mcaddie7

    Eico 2536 Receiver - How to Bias

    Hi all! received an Eico Tube receiver that looked pretty cool for cheap. I checked all of the tubes (same replaced in 69) and they all pass, albeit the 4 matching pairs highlighted in red appear to have more of an “open” according to my tube tester. Anywho, replaced all electrolytic caps and...
    • mcaddie7
    • Thread
    • bias adjust bias adjustement tube amp tube amp help tube receiver
    • Replies: 3
    • Forum: Tube Audio
  16. jcpcali

    Tube Amp Cabinet Thermal Protection

    Hey guys way smarter than me! Hoping for some expert advice on enclosing my Fisher 500C into a custom made desktop. I'm designing a 24" deep x 48" wide office work station into a converted closet in a guest room. It will also contain a Hitachi sr-2004 solid state receiver. I'm worried about the...
    • jcpcali
    • Thread
    • fisher 500 heat transfer tube amp valve amp
    • Replies: 19
    • Forum: Tube Audio
  17. R

    1962 Magnavox console restoration

    I recently scored a turntable from goodwill for really cheap. Everything works- the turntable, radio, and speaker are loud! After doing some digging, I’ve found it is a 1962 Magnavox Micromatic model 1ST622R. I barely found any information online other than forums. I don’t know anything about...
    • reallyaduck
    • Thread
    • 1960's magnavox micromatic record cabinet restoration tube amp vintage 60s 70s vinyl
    • Replies: 33
    • Forum: Tube Audio
  18. C

    Gibson GA-50T Tube Amp What to Replace Debate...

    Debating how much to replace/recondition after realizing reality may not be as bad as thought on this 75 year old amp. After I opened up this vintage Gibson GA-50T guitar amp I realized the noise I thought was the sound of speaker surround decay was actually a half cup of used sunflower seeds...
  19. A

    Codename Revolver

    This EL34 single-ended valve amplifier has been a labour of Love for me. I handcrafted it using the best components I could afford. All wiring is done point-to-point. I also did the copper metalwork and woodwork myself, except for the volume knob and feet. The amplifier is switchable between...
    • Ajay-L
    • Thread
    • 12at7 diy el34 pentode triode single ended tube amp valve amp
    • Replies: 14
    • Forum: DIY
  20. hrudulv

    Using a DAC as Preamp hook up straight to a Tube Power Amp?

    I plan to buy a DAC with volume control and use it as a preamp hook up to my VTA ST70, like this one or this one. This would be my dedicated digital system. Any advices? Thanks for now.
  21. Markmayne

    RCA Portable TT Convert to Powered Speaker.

    I'm looking to convert this turntable into a portable tube powered speaker. I want to use the existing speakers and plan 2 add a Bluetooth module where the input molex plug is. My concern is more of the on off switch which would go where the phono motor molex plug is. I have heard of the...
    • Markmayne
    • Thread
    • mono amps phonograph portable phonograph power switch modification rca tube amp
    • Replies: 4
    • Forum: Tube Audio
  22. Subchannel

    LE Audio VM60 problems

    I bought a pair of LE Audio VM 60 tube monoblocks, and the previous owner have put one of the output tubes in the wrong way (broken tab on the tube socket). I have tried to measure it, and D159 measures different from the other three (one for each output tube. Three measures a bit over 3ohms...
    • Subchannel
    • Thread
    • tube amp tube amp amplifier tube amp help
    • Replies: 15
    • Forum: Tube Audio
  23. L

    Sansui 500EA Headphone Question??

    Hi All, Just acquired a Sansui 500EA that has been converted to 120V and had the caps replaced about 4 years ago. I have been looking at all the schematics but cannot figure out how the headphone jack on this unit puts a load on the amp? I would love to use it as both a headphone driver and a...
  24. Adam G

    HH Scott Restored - Thank you

    I bought an HH Scott 299c (late model) last year from an original owner, and restored it with the usual improvements (cl-80 thermistors on the AC in, selenium rectifier replacement, typical coupling cap replacement, new tubes, etc.) I realized the value of my amplifier early on, and soaked up...
    • Adam G
    • Thread
    • hh scott 299c tube amp
    • Replies: 11
    • Forum: Tube Audio
  25. B

    Recapping Advice

    Hi from Buffalo! I‘m pretty new to this group, and to restoring vintage audio equipment, so I apologize if what I’m asking isn’t as clear as it could be. We’re working on a Decca, Silvertone, Emerson, and RCA (all from the early 60s) and I have two questions: 1. I’m looking for a clear...
    • BuffaloJeff
    • Thread
    • console decca recap and restoration tube amp vintage audio
    • Replies: 4
    • Forum: DIY
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