I highly recommend biamping with Nelson's 6-24 active crossover and powering your Altecs or Faitals with their own dedicated amp.
I have thought about that. I have an SHD studio and I could use that and all I would need is a second DAC. I have had mixed results with analog active xovers in the past and some practicality issue. At the moment, I really like my passive xover. Some exploration is needed.
After scrounging extra parts, I was able to put together the VFET amp this weekend. Thanks to 6L6 for his build guide that made it very easy and quick to assemble. Getting a late start, I was able to take advantage of everyone's experience. It worked immediately. No turn-on/turn-off thumps. No hum or background noises. The sound has lots of musical details. The VFET is now my favorite amp. I set the voltage before connecting a source or speakers. Then ran it for 45 minutes, streaming music, and then made a minor adjustment to the voltage. Thanks to all you have had a part in the design.
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This one continues to improve for the next 20 to 100 hours.
And there are some alternate front ends to try as well..
Enjoy the amp, it’s a wonderful gift from Pa.
And there are some alternate front ends to try as well..
Enjoy the amp, it’s a wonderful gift from Pa.
Enjoy this little amp very much!
You can, if you wish it, IMHO tweak it slightly further following Tungsten's advices and some other posters.
Sound will settle indeed after some burn in as just mentioned.
Have fun
Claude
You can, if you wish it, IMHO tweak it slightly further following Tungsten's advices and some other posters.
Sound will settle indeed after some burn in as just mentioned.
Have fun
Claude
Who would do such a thing to a Sony VFET amp? They turned it into a Frankenamp! That is the beauty of DIY! 
So this is a curiosity. I've measured my P-ch amp temperatures assiduously since I started using it, and I've never seen TO-3 case temps (with an IR gun, through the slots in the top lid) on either device higher than 42C. 39-40C is more typical. And another thing, the fins near the middle of the heat sink consistently read ~2C higher than the TO-3 case tops, which seems like witchcraft.
It's biased at 20V, so it's not running under spec.
I recall mine was pretty hot-running as well. I wonder if the shiny parts might be confusing the IR gun.
It is mine! the amp fits well the mandarins (joke). The driver is a folded PCC88 that is choke loaded - the big trannies, in fact 10K:10k that I wired in series. Great clarity. The driver goes 25Vpp with ease. Without a HV!
The red cables from pre- to main are Isoda cables. [These are wires made up of a selection of many metals to give a harmonical transfer funtion; acqired from advice by J Hiraga.]
There are two plates with the drives and a faux bottom under which I have the power supplies (40V, 12V), filter structures and power buffers.
I have the 1.27 amp idle current and never go beyond the First Watt at home.
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Ah yes and in the back on the left and right of the picture are HORNS. BIG ones. A low, a mid and a high horn.
Here some innards of my build. I deviated and designed my own driver with as constraints: 1) Must have Tube. 2) Must run on the Vb of output stage = <40V. 3) Must allow > 8Watt. 4) Must have good bandwidth. I succeeded. Less than 5 Hz to >50 KHz. or so. Yes it is still inverting, but my preamp also inverts.
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Hello , is there a part list on diyaudio for building the Sony v-fet 2016 Nelson pass Amp.
I have the pcb and the Sony v-gets
Thanks for help
Bart wolters .
I have the pcb and the Sony v-gets
Thanks for help
Bart wolters .
