I think Stixx's masterpiece deserves to be listed here :
http://www.original-ton.net/amplifiers/dao/#
https://www.diyaudio.com/community/...a-zgf-headphone-amplifier.225577/post-5925783
Patrick
http://www.original-ton.net/amplifiers/dao/#
https://www.diyaudio.com/community/...a-zgf-headphone-amplifier.225577/post-5925783
Patrick
Worked out great. It’s not in a chassis yet but here is thread.
https://www.diyaudio.com/community/...pa1688-low-thd-muscle-amp.324931/post-5914394
FFT for 1Vpp into 51ohms:
Sure, Kevin Gilmore's CFA2/CFA3 trumps them all 🏆🏆🏆
especially if build properly (external dual PSUs, etc).
A highly potent, fully symmetrical, balanced class-A amp
and you can switch it between zero feedback or full symmetry anytime by turning a switch.
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Are these balanced mono blocks? Looks more like SE with the red/white chinch inputs on the back of each. But then, why two?
Looking nice!
Are the 80 000uF caps enough for 300 ohms headphones? I though the cap stack should have been at least 10 times higher value than that if you wanna safely drive in ear 32 ohms headphones...A full Farad would be much better along with 120 Amps lithium batteries.
Check this thread:
https://www.diyaudio.com/community/...arallel-mono-at-the-flick-of-a-switch.344690/
I think what I wrote in that thread served as a catalyst for the very latest incarnation of DIY audio Store official ACA
Hi starcat, do you have more information about the CFA3. May be a link or an instruction guide?
Best
Bernd
One of THE BEST :
https://www.diyaudio.com/community/...re-phone-amp-with-very-low-distortion.296545/
Great preamplifier and headamp.
https://www.diyaudio.com/community/...re-phone-amp-with-very-low-distortion.296545/
Great preamplifier and headamp.
One more addition to the many good choices already mentioned, would be the Morgan Jones Mini Tube Headphone Amplifier.
I've just finished building the optimized version with feedback. Tubes used, are ex-Soviet 6N23P.
Followed the schematic provided here, with some minimal modifications.
I've changed the 22kΩ output resistor to ground to a 2200Ω one, in order to minimise pop when inserting my 50Ω cans. And also bypassed all electrolytic caps with ex-Soviet paper in oil & polystyrene film. A nice 'fix' to any OTL using electrolytics.
To my ears at least, there is no loss in transparency due to electrolytics when in parallel with good ol' PIO & film caps.
Power supply wise, i used an indirectly heated 6C4P-EV valve rectifier, followed by R-C filter stages.
Heaters are all AC-lit with an artificial center tap and eleveted at around 50VDC. The amp is dead-silent.
Sound performance is very good, in my opinion.
Better than my previous builds.
For example, it's more detailed and dynamic than my Tortello's Zen-like solid-state.
And better articulated than my valve-rectified 6922 + 6080 OTL.
I've just finished building the optimized version with feedback. Tubes used, are ex-Soviet 6N23P.
Followed the schematic provided here, with some minimal modifications.
I've changed the 22kΩ output resistor to ground to a 2200Ω one, in order to minimise pop when inserting my 50Ω cans. And also bypassed all electrolytic caps with ex-Soviet paper in oil & polystyrene film. A nice 'fix' to any OTL using electrolytics.
To my ears at least, there is no loss in transparency due to electrolytics when in parallel with good ol' PIO & film caps.
Power supply wise, i used an indirectly heated 6C4P-EV valve rectifier, followed by R-C filter stages.
Heaters are all AC-lit with an artificial center tap and eleveted at around 50VDC. The amp is dead-silent.
Sound performance is very good, in my opinion.
Better than my previous builds.
For example, it's more detailed and dynamic than my Tortello's Zen-like solid-state.
And better articulated than my valve-rectified 6922 + 6080 OTL.
Hi starcat. Do you have the gerber file of the CFA3? Thanks so much.PM'ed already
I like topologies like these but the lack of any miller caps with this one bothers me.