Serious design!
I would drill holes in that horizontally aligned heatsink if it does not work well.
The images show up if you open them in a new window or tap on your brower. I uploaded those images.
Hercules amp, 2x30W
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Caps glued by silicone. Rough, but keeps well and is repairable.
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...small but heavy EL95 PSE with 6N16B in drive and EZ80 and two 5787WA VR`s in power supply... output transformers made locally, UL tap, 4k5 primary... amp schematic is basically Lorelei EL95 PSE (google it pls.), and psu was made with tube full wave rectifier followed by CLC to the output tubes, and added two 5787WA VR`s in series to get 200VDC stabilised for driver tubes... not to brag or anything, but I didnt expect much (more like made it for fun and practice), but I stand corrected.... this thingie SINGs 
(not too loud, but sweeeeeeeeet)...
UL mode is soon-to-be tested, dont have to say much about it right now... expected power is cca 2W in triode, and close to 4W in UL (I was told, I suck at calculus but like to make things
)
(not too loud, but sweeeeeeeeet)...UL mode is soon-to-be tested, dont have to say much about it right now... expected power is cca 2W in triode, and close to 4W in UL (I was told, I suck at calculus but like to make things
)Attachments
Great job love the brass acorn nuts on the transformers . What value is the choke and from where ? Regards...and a few more
Great job love the brass acorn nuts on the transformers . What value is the choke and from where ? Regards
thx
the choke is 8H 200mA 69R and was wound locally by the same guy that made the OPTs... I had two chokes done earlier for another project and used only one, so this one was at hand and already payed for so....
Some mechanical damping as well ?
Yes, but not for the production. Ok for a prototype, when it needs frequent tweaking and change of schematic.
Awesome man-cave! I'm coming to same thing: several amps, several pairs of speakers. .. can anybody suggest any good amps/speakers switch? to vary the herd.
...and a few more
Yes, but not for the production. Ok for a prototype, when it needs frequent tweaking and change of schematic.
production?
production?
Even if it is DIY for yourself only, final version should be more accurate. However, I remember one guy in the laboratory I worked, made a breadboard of a reproduction amp for a tape recorder. He dipped the whole breadboard into an epoxy compaund.
Mars Tube Audio EL84PP project
By way of introduction I'm posting my first valve amp build - an EL84PP kit from Mars amps here in South Africa (Stereos Kits - Mars Tube Audio). A modest build by the very high standards on this forum, but I'm very happy with it.
It is an ultralinear configuration using EL84s in a push-pull arrangement. The output transformers were wound here by Mars - I requested 4Ω taps in addition to the usual 8Ω. The valves are Sylvania 6U8 pentode-triodes for the preamp/phase splitter and Tube Amp Doctor EL84-STRs for power.
The circuit:
The interesting bits underneath:
A closeup (the toggle switch I added to switch between open-loop and negative feedback modes):
Singing away (It's sitting on top of my other amp so don't think it grew big). It is as happy driving the Beovox 2400s or the big Kef Q90s:
It sounds really wonderful - I'm so pleased! I want to use this as a basis for playing around with different design ideas (regulated supplies, phase splitter configurations, remote control for volume and inputs), and also work on the aesthetics - fascia, covers, perhaps some vintage style VU meters.
By way of introduction I'm posting my first valve amp build - an EL84PP kit from Mars amps here in South Africa (Stereos Kits - Mars Tube Audio). A modest build by the very high standards on this forum, but I'm very happy with it.
It is an ultralinear configuration using EL84s in a push-pull arrangement. The output transformers were wound here by Mars - I requested 4Ω taps in addition to the usual 8Ω. The valves are Sylvania 6U8 pentode-triodes for the preamp/phase splitter and Tube Amp Doctor EL84-STRs for power.
The circuit:
The interesting bits underneath:
A closeup (the toggle switch I added to switch between open-loop and negative feedback modes):
Singing away (It's sitting on top of my other amp so don't think it grew big
). It is as happy driving the Beovox 2400s or the big Kef Q90s:
It sounds really wonderful - I'm so pleased! I want to use this as a basis for playing around with different design ideas (regulated supplies, phase splitter configurations, remote control for volume and inputs), and also work on the aesthetics - fascia, covers, perhaps some vintage style VU meters.
12ax7 12au7 preamp & breadboard
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
