short review
just posted my findings on my sony vfet amp:
Sony Vfet Illustrated build guide
best regards
just posted my findings on my sony vfet amp:
Sony Vfet Illustrated build guide
best regards
Nelson's talk at Burning Amp 2018?
From Stereophile:
"Nelson Pass will devote most of his talk to the newer Sony VFET amplifier kits he is developing for the store at diyAudio. These will use up Nelson's remaining Sony VFET transistors—about 400 channels' worth."
Burning Amp 2018 Set For September 30 in San Francisco | Stereophile.com
From Stereophile:
"Nelson Pass will devote most of his talk to the newer Sony VFET amplifier kits he is developing for the store at diyAudio. These will use up Nelson's remaining Sony VFET transistors—about 400 channels' worth."
Burning Amp 2018 Set For September 30 in San Francisco | Stereophile.com
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Since the store will be getting a kit soon and I’d be using it for my 1st Vfet build, does anyone of an idea what I should do w a set of 2SJ28’s and 2SK82’s I’ve acquired?
Agree with ZM.
After the new diyaudio vfet kit, may find yourself curious about the two
older projects:
http://www.firstwatt.com/pdf/art_sony_vfet_pt1.pdf
http://www.firstwatt.com/pdf/art_diy_sony_vfet.pdf
Or you can send the vfets to ZM for proper disposal. 🙂
After the new diyaudio vfet kit, may find yourself curious about the two
older projects:
http://www.firstwatt.com/pdf/art_sony_vfet_pt1.pdf
http://www.firstwatt.com/pdf/art_diy_sony_vfet.pdf
Or you can send the vfets to ZM for proper disposal. 🙂
Hmmm alright....I got so many other projects going on that they’ll be sitting for quite sometime but stash them away for a rainy day
Now what?
Several months ago I was getting nowhere with my V-FET build and hoping to see some progress I thought I would change the layout and some of the wiring. I had progressed to the point of installing the V-FET's when I did this. After the change in layout I tryed to proceed with the one channel without any success. At this point I noticed that I had reversed the wires going from the bridges to the power supply board. Any thoughts on what damage I may have done?
Several months ago I was getting nowhere with my V-FET build and hoping to see some progress I thought I would change the layout and some of the wiring. I had progressed to the point of installing the V-FET's when I did this. After the change in layout I tryed to proceed with the one channel without any success. At this point I noticed that I had reversed the wires going from the bridges to the power supply board. Any thoughts on what damage I may have done?
I like SMPS in power amps a lot. Any experience using SMPS with this project? How is it expected to affect the sound if good (audio grade) "soft-switching" +/-30v SMPS is used instead of linear PSU?
I looked into this pretty thoroughly and it could work fine. However, I went with linear supplies because they were simpler and cheaper.
Most SMPS' are not designed for the sort of continuous current that a class A amp requires, and the only reliable supplier I could find that produces suitable supplies were Meanwell - and the price was ultimately more that a linear PSU. Also, as Nelson says, the noise needs to be filtered very well. Many SMPSs are only specified for transient current and are not properly specified for the current requirements of a class A amp.
Most SMPS' are not designed for the sort of continuous current that a class A amp requires, and the only reliable supplier I could find that produces suitable supplies were Meanwell - and the price was ultimately more that a linear PSU. Also, as Nelson says, the noise needs to be filtered very well. Many SMPSs are only specified for transient current and are not properly specified for the current requirements of a class A amp.
Thanks arky for the info, for some reason I was thinking that I needed a 19 volt supply to test the V-FET's. After testing the two seem to be good and test the same as the unused pair.
well, SMPSes are different.
1. sony ta-n9 - up to 80W in class A, using SMPS and sounds fantastic
2. sony ta-n900 - up to 200W class AB, also using SMPS (very similar to N9)
3. sony ta-n86 - up to 20W in pure class A, SMPS as well (classic)
4. sony ta-n88 - up to 180W in class D using v-fets
I have all of these and most of all I like N9. However their SMPS has shunt regulator at output. And yes, they all sound fantastic.
Thanks, Nelson. I am looking to use 300W rated "audio grade" soft-switching SMPS, usually found in "pro" amps. For each channel. So, at +/-30V on rails and 4ohm load it should be not drawing more than 2 amperes. I also think to use CLC filter on PSU output.