Papa knows us crazy amp builders too well. He also chose well for his VFET coupling caps.
I usually don't parallel output coupling caps unless the PCB has been specifically designed for such. I have left the VFET amp as designed in this area, partly because I already know how difficult it is to remove a big snap-in style cap from the board.
I do not recommend removing the big coupling capacitors from the VFET boards if they have already been soldered in. This may damage the board.
I usually don't parallel output coupling caps unless the PCB has been specifically designed for such. I have left the VFET amp as designed in this area, partly because I already know how difficult it is to remove a big snap-in style cap from the board.
I do not recommend removing the big coupling capacitors from the VFET boards if they have already been soldered in. This may damage the board.
I have just hooked up the Vfet to my set of Energy22 Reference Connosieur speakers.This is my "good" set of speakers.Previously was hooked up to EPI M50's,small bookshelves.I am shocked how good this amp is with these speakers.For one the bass is solid,tight and really reaches down low,so much so I almost wish I had a tone control.The soundstage is really wide.Highs,especially electronically generated ones are spooky sounding.This is one incredible amp.Here,back in the 70's I used to be caught up with "how many watts" as that was the marketing back then.From what I see with the sound levels I am comfortable with this 10 watts is plenty.The winners in the next round are in for a treat.
I was thinking about how everyone would complain if I didn't put a bypass cap there.
I love the Omegas... they are super transparent and revealing with solid and precise imaging... the only problem is of course the lack of bass... but they match pretty well with an external subwoofer... right now I'm using the new SVS 3000 micro sub which comes with a handy app to set the volume/cross-over/phase/polarity/etc.. that makes adjusting and matching pretty painless.
I'm not a big fan of subwoofers, per se, because I can live without deep punchy bass for most of my music listening (e.g. jazz vocals), but there is so much interplay between the lower notes and the midrange that without a proper low end, everything else sounds really off-balance and annoying. FWIW, that's where I think the B&W 606s do a good job of balancing out the full spectrum even though it can't go super low.
Anyway, back to the Omegas, with proper break-in and ancillary equipment, it's my favorite speaker for female jazz vocals where they go from soft intimate whispers to bold loud high jams... with the volume level set loud enough for the whispers, the louder passages can sometimes sound shrill and shouty on some speakers, but the Omegas have a smoothness that sounds lively/hot but not shrill.
you can also do the same with the 1000uf coupling cap in the input board ,
cost peanuts and interesting results
.The amp sounds great with the Omegas... Not sure about the impedance dips with the B&W 606s, but I'm not noticing any obvious frequency imbalances or distortion... Actually, I'm pretty impressed that how well this amp can drive the 606s... bass is punchy and gets pretty loud, though it is at its limit I suspect.
pretty sure quoting myself is a noob mistake but I just wanted to post a quick update on how the amp is working out...
- running 36 hrs continuously didn't produce any smoke, lol, and the temperature of the components seemed pretty stable (though hot, about 140F on the Q3 chip... couldn't get read from the VFETs, my laser thermometer kept reporting 105F though it felt so much hotter than that)
- listening with the Omega SAMs (95dB), the amp was able to get louder than I needed it to (room 20'x20'x10', listening 14' away)... with the B&W 606s (88dB), it was able to get just loud enough but any louder it seemed to be saturating, though it could have been my DAC/pre-amp (Chord Hugo2) that was maxing out.
- with the Omega SAMs, the amp sounds amazing... very lively and musical on a spacious soundstage with pinpoint precise placement of voices and instruments.... with B&W 606s, the soundstage was shallower/flatter and the placements less precise, but still sounded great, the punchy bass and overall tonal balance made this combo very fun to listen to.
- on a personal note, what I listen for is realism...
1. tonal balance / accuracy - e.g. can I differentiate a clarinet from an oboe or a sax (fwiw, I don't think I have ever been able to differentiate a violin from a viola even in in-person listening, lol)...
2. clarity / transparency - e.g. can I understand the lyrics, or appreciate how notes are caressed, etc.
3. soundstage / precision - e.g. can I separate out where the singers in a chorus are standing, e.g. sopranos vs altos, tenors, etc... can I place individuals performers without effort
* I find that when these elements are all present, I'm transported to my happy place where I can emotionally connect with the performance... done super well, I am transported to the performance venue itself and can just be immersed in that musical moment... done poorly, I change tracks or turn down the volume or move on with other tasks
- having said all that, this amp with the Omega SAMs put me in my happy place so many times with so many different albums that I have spent way too many late nights listening to old albums instead of getting ready for work the next morning, lol.
- by comparison, the First Watt F1J comes close but the soundstage is a bit shallower, and the sound is a bit bright... this Sony VFET amp is way more relaxed and easier to listen to, while at the same time being more transparent and dynamic... also, the F1J (which used to be one of my favorites) appears to have a tighter range of volume levels where it sounds right (too soft and it loses clarity/definition... too loud and it sounds shrill)... whereas the this amp sounds great over a greater range of volumes.
- lastly, the poor Schiit Aegir loses on many levels... the soundstage is completely flat by comparison and the placement of voices and instruments completely fuzzy and poorly defined... tonally it sounds deadened / rolled-off / muffled by comparison to either of the other 2 amps... that's not to say it is a bad sounding amp in its own right, it sounds way better than my Denon AVR (300W) or my Temple Audio Bantam Gold (25W) amps, both of which suffer, imo, from having way too much "digital-harshness".
- in conclusion, I'd like to again thank Nelson Pass and the rest of the team here for making this kit possible, and for this wonderful opportunity to get reacquainted with my music collection all over again... this was truly an awesome experience and hopefully the start of many tinkering projects... next up, inspired by all the pretty pictures other people are posting, I'm going to re-wire my amp to eliminate all the excess runs draping over other components... then I think I might experiment with replacing the power supply with a massive battery bank... then... ... ...
short game not much alternative at 25v...you can also do the same with the 1000uf coupling cap in the input board ,
cost peanuts and interesting results
Thanks for the recommendation! Actually Qobuz has the album in 88.2kHz 24bit. Really lovely to listen to (not yet on the VFET!). I find that Harpsichord can be a bit strident to listen for extended periods in certain recordings, but this recording is exquisitely produced and not harsh at all.
Rafa.
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