• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Photo Gallery

Finally able to post a picture on one of my projects using sweep tubes
 

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My 300B amp. Design shamelessly taken from Ale Moglia. 6SF5 drivers, SS mu-followers and interstage buffers, Rod Coleman's regs on 300B filaments. Buffers and regs running heatsinks quite hot, about 25 degrees above ambient
CLC power then split into separate CRC for each channel
 

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The 36LW6 amp after a conversion. It's now powered by a 12V ATX supply and several (5 - left output, right output, 6F12P stage, 6N8S stage, bias) boost converters and uses 6P36S. Same circuit though. OP now 292V, 80mA with 5.5V heaters (because 12V and long parallel 18 AWG wire, and 50$ ATX) but I like it, and it's close enough to the minimum of 5.7V.

I'll let you all know how longevity goes.
 

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Soldersober, is this your first build? Nice aesthetics:)

Thoughts about the sound of glass and sand combo amp? I’m no purist, I’m wondering about what’s different;-)
Thanks. This is my second tube amp build, first one is here https://www.diyaudio.com/forums/tubes-valves/71300-photo-gallery-857.html#post5620266
Glass and sand sound - don't know, I like it, but then I did not do any direct comparison. The SS parts are supposed not to add anything, but who knows
 
The 36LW6 amp after a conversion. It's now powered by a 12V ATX supply and several (5 - left output, right output, 6F12P stage, 6N8S stage, bias) boost converters and uses 6P36S. Same circuit though. OP now 292V, 80mA with 5.5V heaters (because 12V and long parallel 18 AWG wire, and 50$ ATX) but I like it, and it's close enough to the minimum of 5.7V.

I'll let you all know how longevity goes.

Koda I think you want get music drank :cheers: with all those meters :spin: .....just kidding....:)
 
Hello to everybody, I just want to share my experience, I was looking for a customised option on power transformer also less expensive than the usual Hammond or Edcor, also because I have to deal with expensive delivery cost to Philippines, so came across with a Chinese company, they really open to build any power or OTP transformer, in fact I need for my next project a 9.7V secondary so I just design the transformer for my need send to them and they did it in a very short time, I place the order on Nov.4 and received on Nov.14 with UPS Express, received, tested and I am very happy with the product, total cost for a 125w transformer delivery included $56.23.
Customize 85w 125w Power Transformer for Tube AMP HIFI EXQUIS Quality Guaranteed-in Amplifier from Consumer Electronics on AliExpress

All the best to everybody :)
 

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Finally finish my last build 10EW7 parallel tube amp with 6N2P for the tone stack, bamboo chassis. Just made all test and I am absolutely happy with the result, 6.7 watts x channel, separate power supply, THD 3.9% just 2nd harmonic. How it sound? Crispy, clear, sound stage incredible, open wide vocals, even at max volume where the scope reveal a clear distortion is very difficult to ear it.
Has been a long journey for me because this is the first amp completely design by myself, lots of work on simulation then in reality things are little bit different, but I did it and I am very happy with the result, I really push to the limit the second triode of the 10EW7 using the 10w plate dissipation to limit but the tube handle it very well, get just very hot but no other bad sign, now tested with all kind of music for several hours and I am really surprised by the quality of the sound...all the best to everybody
 

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Finally finish my last build 10EW7 parallel tube amp with 6N2P for the tone stack, bamboo chassis. Just made all test and I am absolutely happy with the result, 6.7 watts x channel, separate power supply, THD 3.9% just 2nd harmonic. How it sound? Crispy, clear, sound stage incredible, open wide vocals, even at max volume where the scope reveal a clear distortion is very difficult to ear it.
Has been a long journey for me because this is the first amp completely design by myself, lots of work on simulation then in reality things are little bit different, but I did it and I am very happy with the result, I really push to the limit the second triode of the 10EW7 using the 10w plate dissipation to limit but the tube handle it very well, get just very hot but no other bad sign, now tested with all kind of music for several hours and I am really surprised by the quality of the sound...all the best to everybody

Love the Tranni cage. Good one.
 
Line level Preamp and PSU for a Phono amp using the CCDA circuit as recommended by Coda and others.

PSU is 330 0 330v 60mA mains tmr, first cap 2 x 220u in series, 10H choke, then 820u 400v cap in parallel with two VR150/30's - HT 1 309v. HT two after 1k5 R and 50u cap each channel 288v.

Valves 2 x 6H8C. Tried LED as V1 bias, got better balance with resistor. All values the same - ish apart from 300r = 310r, 430r = 470r, I used what I had. Consequently each channel running at 14mA instead of 20mA, this is better for my mains tfmr too.


There's a few minor bits to do, like labels, EG PC, CD etc, better knobs and I have to find some screws.


Andy.
 

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