NightFlight
500+ Head-Fier
- Joined
- Jan 3, 2013
- Posts
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What the heck are the zip ties tied to?
What the heck are the zip ties tied to?
This is my DIY headphone amp for my HD800 wired in balanced mode. The circuit is a single -ended triode design using one 6072A driving a 45 tube, yielding an output of about 1.5W per channel. The power supply to the filament of each 6072A and 45 is DC and independently regulated. The B+ to each channel is also independently regulated using a tube circuit consisting of 1 OC3, 1 12AX7 and 1 6AS7G. I use a metal base GZ34 as the rectifier. All transformers (amorphous core for the output) / choke are made by Tamura Corp., Japan.
I have used a variety of caps in this amp, consisting of 4 Mundorf M Tube Cap, one pair of Blackgate electrolytic, one pair of Audio Note silver foil (signal), 4 V-Cap TFTF Teflon (bypass) and multiple Auricap XO metalized polypropylene.
I am extremely happy with the sound of this amp, though all the caps have cost me quite a sizeable sum!
If anyone is interested in bypassing capacitors, this is an informative write up:
http://www.hawthorneaudio.com/forums/viewtopic.php?f=1&t=3763
Well I suppose it was inevitable I have had a JFX 2.2uF 250V Polypropylene Film cap that has been sitting in my parts box for a while now (I brought it at the same time as the 100uf films as it only cost £1.72) and ended up soldering it in as film bypass cap across the last electrolytic filter cap in the Crack today.
I feel there has been a slight improvement in fluidity and presence a touch more body to vocals and also the top end has slightly more crispness to the shimmers and tinkles without importantly for me adding any brightness.
It now opens up a can of worms with respect to trying something like a PIO or SIO or further bypassing of the current bypassing cap with a smaller Teflon.
I will let the cap burn in for a week or two in situ while I mull over which options to have fun experimenting with next.
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serious build there. You got anymore pics. Did it take long to make?
This pic shows the size of the amp relative to my HD800. The output tubes shown are EML 45 Mesh. In the previous picture, I was using NOS Tung-Sol 45 circa 1950s.
This amp weighs 24kg. It took me 7 weekends to built.....thoroughly enjoyed every moment of it!
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P.S. since this is a capacitor thread, would you guys recommend film caps over multi-layer ceramics for an active crossover design? I am leaning towards the films, but would appreciate a second opinion.
Do you listened Rike Audio (PIO) S-Caps yet? Thank you!
Have read on the Internet that some people say the Duelund Cast Capacitors are the best they have ever heard. Hope someday you might consider reviewing them Jon L.