• The move to the new server is done. There are some software and database maintenance updates in process. This has us passing the hat around to help out. We appreciate any donations. Seriously, even a dollar helps. The payment page may be found here - https://www.audiokarma.org/support.html

12ax7

  1. R

    Looking for Fosgate Signature Phono Stage Schematic.

    Hello everyone! Has anyone here worked with the discontinued Fosgate Signature Phono Stage? I'm currently searching for the complete schematic diagram of this tube-based phono preamp, either available for download or purchase. I'm deeply interested in studying, restoring, or even possibly...
    • RJA_LEBANON
    • Thread
    • 12at7 12ax7 ecc81 ecc83 fosgate jw fosgate musical surroundings phono preamp phono stage riaa
    • Replies: 1
    • Forum: Tube Audio
  2. MisterDK

    Psvane 12AX7 questions -

    Hey boys and girls! I have a question regarding Psvane 12AX7’s.. Are their “Art Series” much better than their standard 12AX7? Are they worth the 3x greater cost? Also wondering what you-all who have tried them, think of the Electro-Harmonix 7025… Good, bad or..? Asking ‘cause I recently...
    • MisterDK
    • Thread
    • 12ax7 7025 electro-harmonics 7025 psvane 12ax7
    • Replies: 39
    • Forum: Tube Audio
  3. Carbsandcaps

    6n4, 12ax7 confusion

    I have an opportunity to buy some American made JAN 6n4’s. I’m under the impression that the 6n4 was a Chinese tube number for a 12ax7. I’m also finding online that the 6n4 is a single triode. Can someone clear this up for me?
  4. Synergy

    EL34/6CA7s + 6GH8A + ECC83/12AX7s ... Superb !

    Sweetest sounding amp with EL34 / 6CA7s + 6GH8A + ECC83 / 12AX7s and all selfmade transformers. Added a stereo bluetooth though, but its switchable. Demo video
    • Synergy
    • Thread
    • 12ax7 6ca7 6gh8a amplifier ecc83 el34 vacuumtube
    • Replies: 15
    • Forum: Tube Audio
  5. Logan_Nolag

    C2700 uses 12AX7A tubes are regular 12AX7 tubes compatible?

    One of the tubes in my C2700 seems to have gone bad. I contacted my dealer and they said they could only sell me a full set not individual tubes so I thought this would be a good opportunity to upgrade them. Unfortunately however it seems like there are no new production 12AX7A tubes available...
  6. ceylon

    is this raytheon 12AX7A a hitachi?

    "raytheon registered"...is that hitachi? something else?
  7. meako

    Nobsound Tube Preamp

    I recently acquired this preamp from Nobsound/Douk Audio. It is based on the Marantz 7 line stage with the Shigeru Wada circuit mod. It had two 12ax7s and two 12au7s from PSVANE. Stock tubes sounded awful. It was very metallic and the bass was really weak. So, I ended up replacing the 12au7s...
    • meako
    • Thread
    • 12au7 12ax7 5814a douk nobsound shigeru wada srpp tube preamp
    • Replies: 34
    • Forum: Tube Audio
  8. jpatti75

    I need a tube lesson

    Hi gang, I need a lesson on new vacuum tubes on the market. While there are many review of modern tubes on the net, many of the reviewers represent the guitar amp crowd, while limited reviews that I have found reference modern tubes for use in vintage HiFi stereo applications. Quite a few...
  9. P

    Mc240 Cathode Follower 12ax7 tube recommendations please

    I am confused about what tubes should go into this position as I understand they get run a bit hard there. I have new production tubes and am not certain if they are safe there either. I also would like to know if those tubes should be matched and measure high GM to have maximum effectiveness...
  10. C

    Magnavox 9302 - Rebuild

    I recently acquired a Magnavox 9302, and I'm in the process of rebuilding it. I've stripped the chassis completely, and I'm nearly done doing the mechanical work on the chassis... soldered over the extra holes, body filler, all the aesthetic stuff. I'm having some trouble with the schematic...
    • Cameron06
    • Thread
    • 12ax7 93-series 9302 amplifier edcor el84 magnavox tubes ultra-linear
    • Replies: 64
    • Forum: Tube Audio
  11. IEHAGY

    Dead preamp tube or something worse ?

    It started with louder than normal noise floor / hiss that I was able to control by adding a passive preamp into my chain ... then it started taking longer than normal for it to heat up .... and now it wont heat up at all. I'm wondering if its time to take my beloved Juicy Music Extreme to a...
    • IEHAGY
    • Thread
    • 12ax7 juicy music tubes
    • Replies: 9
    • Forum: Tube Audio
  12. jeeem

    Matching tubes to amps

    Although I have several "valve" amps, I'm only beginning to discover TubeWorld. I don't even know what tubes are inside some of my vintage equipment because I've never looked and wouldn't understand the significance of what I find. Now, with a fair amount of time on my hands, I want to learn...
    • jeeem
    • Thread
    • 12ax7 300b el34 kt88
    • Replies: 10
    • Forum: Tube Audio
  13. artsybob

    12AX7/ECC83 Recommendations?

    Does anyone have a recommendation for a good 12AX7 (either new production or NOS) for a tube amp phono stage that isn't ludicrously priced? Would like to hear what the AudioKarma community thinks
  14. R

    Testing on Hickok 800 - 12AX7 vs ECC83 BIAS setting

    I couldn't find any discussion of this, so I'd appreciate your take: Hickok 800 roll chart says 12AX7 wants a BIAS setting of 12, but the Hickok 800/800A euro tubes supplement says ECC83 wants BIAS at 7. No other settings differ. Should be no difference beyond the name, right? As a 12AX7...
    • ring
    • Thread
    • 12ax7 ecc83 hickok
    • Replies: 16
    • Forum: Tube Audio
  15. John Parkey

    difference between Telefunken 12AX7 tubes

    Greetings everyone, please point me to previous threads if this has already been covered. Looking on Ebay, you can find Telefunken 12AX7 tubes with the diamond, made in Germany, 2 letter date code for $30-50 and then what appears to be same tubes for close to $200 or more. Just a single tube...
    • John Parkey
    • Thread
    • 12ax7 12ax7 tube rolling german tubes telefunken
    • Replies: 6
    • Forum: Tube Audio
  16. BostonBrian

    Fisher 800b Tube questions

    I have a question about tube 12AX7 at position ECC83 just in front of the WX writing. When I bought this unit I noticed right away that it was the only tube not lit. I know that doesn’t necessarily mean that it isn’t working, but still I’ve never seen it lit or hot. I thought maybe it just...
  17. N

    Using short plate and long plate tubes together...

    Hi All, Does anyone have any experience using both short and long plate tubes in the same amp? I have a 1959 Pilot 245-A integrated amp, and I just purchased a lot of 7 RCA 12AX7 tubes. The tubes tested NOS apparently, and four of them are long plate, and three short. My amp uses six preamp...
    • njm
    • Thread
    • 12ax7 pilot 245-a preamp tubes
    • Replies: 9
    • Forum: Tube Audio
  18. John Parkey

    Jolida Glass FX III DAC tube recommendations

    Greetings. I have searched and did not see a tube recommendations thread for the Jolida Glass FX III DAC. I have that DAC with all of the factory upgrades. Have used Russian Electro Harmonax 12AX7EH tubes in place of stock tubes and that made a nice difference, richer sound, better dynamics...
    • John Parkey
    • Thread
    • 12ax7 jolida dac tube rolling
    • Replies: 51
    • Forum: DACs
  19. Moonwatcher

    Why wont this Little Bear t11 work with 12ax7s?

    Hello, all, I have a Little Bear T11 that I accepts either 6n2 or 12ax7 tubes. There is a switch next to each tube for picking one or the other. The stock 6n2's sound fine, but I wanted to try vintage 12ax7s that I'm pretty sure worked last time I tried them. But not a single one of them...
  20. kcline

    Pictures of Japanese NEC 12AD7 Tubes

    These came out of a early Sony R to R. Hard to find, as a retired tube dealer I have never seen more then a handful of these. Sockets in the r to r were marked 12AD7/ 12AX7
  21. thorpej

    Make switching between 12AX7 / ECC83 and 6N2P easy

    Hey folks... I wanted a way to make it super easy to switch between 12AX7s and 6N2Ps without having to rewire the socket, so I whipped up this little helper board that sits in between the 6.3Vac heater winding and the sockets. It uses one of those little slide switches that are used to select...
  22. Little Wolf

    My Homebuilt "Mid-Century" Style Amp

    Hi All, This is my first AK post. Just wanted to share a recently completed project of mine: a homebuilt transistor-tube hybrid integrated stereo amplifier in the style of an early 1960's household hi-fi stereo set. The set was built as a modular system; with the exception of the power supply...
    • Little Wolf
    • Thread
    • 12ax7 diy diy project homebrew husky electric hybrid amp jlh 1969 tube amp tube amp build vintage tube amp
    • Replies: 28
    • Forum: General Audio Discussion
  23. DonP1

    Preamp tubes

    Or, why not use 12AX7's for everything? I come from a guitar amp background. Wondering why you would use anything but the 12AX7? Granted, some designs came out before this tube was produced. But is there a "tone" reason to use other tube types? Going to be doing some home brew stuff, so just...
  24. B

    Audio Research SP11 vs Luxman CL-35 MkIII

    Greetings. I am looking for feedback from those that have heard Audio Research and Luxman gear in their experience. I recently acquired an SP11 hybrid preamp with stock tubes. Plugged it in to the main system in place of a Luxman CL-35 mkIII, and instantly noticed a difference in imaging and...
    • briguy986
    • Thread
    • 12ax7 audio research imaging luxman matsushita preamplifier quicksilver soundstage telefunken
    • Replies: 9
    • Forum: Tube Audio
  25. kcline

    Space-Tech Lab. Line stage pre-amps QA-001 & QA-111-U

    PleaseSee pictures. Had these for a long time. Have a great story that came with these. Gentlemen I got these from told me he was a professional tube listener for Conrad Johnson and other companies he had all CJ equipment said it was top of the line. He needed 7 Telefunken 12AU7 used tested...
Back
Top Bottom