Thank you, Zman! I am indeed loving the sound of the VFET amp. 10w is not a lot, but it does indeed punch above its weight class. Driving some rather inefficient 83dB near field speakers, and in near field (4ft or so), it is plenty loud and bass is nice. Imaging and stereo soundstage are superb.
I am just going to relax and enjoy its beautiful sound during burn in. Then assemble the rest of the chassis and put it out into the main system. I might try it with my 93dB sensitive dual 3FE25 Karlsonator speakers. It’s a special amp that’s for sure.
I am just going to relax and enjoy its beautiful sound during burn in. Then assemble the rest of the chassis and put it out into the main system. I might try it with my 93dB sensitive dual 3FE25 Karlsonator speakers. It’s a special amp that’s for sure.
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It is for the store. I expect to ship them next week.
I really do hope the store offers the Aleph J as a complete parts kit (just like F5 or F6 Parts Kit currently being offered), as I am really a newbie, so I just buy and then follow the build guide provided.
I was able to make the Korg B1 Nutube kit very nicely, I do hope to complement it well with the Aleph J's
Small power classA amps are best enjoyed when used in biamp system on mid/tweeter section only
Leave woofers for high current classAB.
I biamp with 2SJ28 single ended amp for the highs and THF-51S amps for the lows. I have tried other amps (not VFET/SIT) for the lows and the SITs beats them all. My singled ended SIT amps are also better than the push-pull Sony TAN-5550 VFET amp for the low end.
The cross-over point for my speakers is around 900 Hz. This means about half the music range is covered by each speaker section. So, it is not surprising that the low end benefits from good amplification. Also, the overlap between the lows and highs benefits as well.
The cross-over point for my speakers is around 900 Hz. This means about half the music range is covered by each speaker section. So, it is not surprising that the low end benefits from good amplification. Also, the overlap between the lows and highs benefits as well.
I always cross at 150Hz, so its a very different consideration for classA and woofers...
Nah... either get a bigger (more efficient) woofer, or a bigger class-A amp, or both
naaah...four 15" woofers (two per side) at ~96dB/w/m each is adequate for me for now
It is a big thump. Enough to raise to level of issue to deal with. I don't know about movement of cone.
I m not surprised that turning the VDC to the amp cold off like that produces that effect.
If that thing wasn't $5k USD for just the midrange horn (the wood part only)...
IMO 83 dB speakers is not a good match for this amp at all. Hard to get anything to sing. I have 103dB speakers and there is a difference between this 10w and the 25w. The headroom is needed, it may not play that much louder louder but it plays 'easier'.
It’s not an issue on M2, which is why I asked about possibility of having a slow long ramp up and down on the bias circuit.
Regarding 83dB speakers - I know what you mean but for near field listening, it’s just swell.
Having a powerful preamp that can swing a solid +/-15v with 14dB of gain helps too.
Which one were you looking at? The 600Hz ones I believe are much more expensive.
The guy is definitely a genius with this horn acoustics and I learned alot from his video experiments but his clientele must be financiers.
if it is not abrupt (and I'm certain that Pa wouldn't leave it out of SR Lab with question marks), no reason to worry
It’s not an issue on M2, which is why I asked about possibility of having a slow long ramp up and down on the bias circuit.
Regarding 83dB speakers - I know what you mean but for near field listening, it’s just swell.
Having a powerful preamp that can swing a solid +/-15v with 14dB of gain helps too.
my M2 with your PS board works fine. But there is alot in between the power switch and the speaker. In the VFET is kinda direct 3A switch off at the speaker. I need to see what happens if I turn the meanwell off instead to add some electrical separation from the switch event.