I'm thinking if it's the Leaky JFET then it would have some offset when it's shorted.
I will test this tonight.
Any other things to consider would be most appreciated.
Thanks,
I will test this tonight.
Any other things to consider would be most appreciated.
Thanks,
If you're referring to this version: http://www.diyaudio.com/forums/blogs/tea-bag/352-sony-vfet-version-2-al-boards-build-blog.html Tea-Bag might still have some in stock.
That sounds like a ground loop to me. If it were a bad device it would only affect one channel.
Ground loop.
Start by rotating transformer to minimize noise.
Then look at the "loop area" formed by internal wiring through RCA
grounds, cable ground, source ground.
Start by rotating transformer to minimize noise.
Then look at the "loop area" formed by internal wiring through RCA
grounds, cable ground, source ground.
Post a pic of your build, showing input wiring and grounding scheme. Maybe we can spot how the loop is formed.
Buzz solved
It was the transformer. My 100db horns they are quite sensitive to noise.
So I rotated it about 40 degrees and minimized it.
I guess I have been lucky with stereo chassis in the past and now I mostly make mono block amps.
Thanks Nelson.
It was the transformer. My 100db horns they are quite sensitive to noise.
So I rotated it about 40 degrees and minimized it.
I guess I have been lucky with stereo chassis in the past and now I mostly make mono block amps.
Thanks Nelson.
Hi qwertyl,
Can you tell me if the Schurter mains switch you used has enough thread length with the locknut to allow for the 10mm depth of the aluminium front panels for the amps in the DIYAudio store. From the data sheet on the switch it looks like the thread length is only 10mm max, which leaves no thread to screw the lock nut on.
Your build is beautiful by the way, and the test documentation is bar none.
Can you tell me if the Schurter mains switch you used has enough thread length with the locknut to allow for the 10mm depth of the aluminium front panels for the amps in the DIYAudio store. From the data sheet on the switch it looks like the thread length is only 10mm max, which leaves no thread to screw the lock nut on.
Your build is beautiful by the way, and the test documentation is bar none.
Thanks. Yes, I used the mains switch with 10mm aluminium front panel and it fits perfectly. I think the data sheet shows that the panel should be max 10mm thick, the thread is longer.
One more question for you on the switch qwertyl, how did you drill the 19mm mounting hole required in the front panel?
I haven't 🙂 This time I ordered fully customised front panel from Hifi 2000.
But please have a look at my Aleph J build - I used holesaw to cut those big holes for VU meters in 10mm aluminium from panel.
i use a cone drill for this work, don't rush and then it's easy. if you have a thick plate you need to drill from both sides then you don't have a step on one side.
https://www.google.ch/search?q=dril...biw=1280&bih=633#tbm=isch&q=cone+drill+35mm&*
Using a drilpress for such a big hole in 10mm aluminium is definitly a good idea as well as very securely clamping the work down. I've done 30mm holes with a cone drill, like that in these Modushop/Hifi2000 front plates. Masking tape the whole front face off, as the metal shavings will scratch unless you plan to refinish it.
I finished my build a month ago. Since then, every time I listen to music, I'm astonished by the sound this amp is producing. AlephX that I used before was great but this VFET amp is completely a different league. So much clarity and spaciousness in the sound, incredible. Some pictures of the build are attached. I found an empty new box for Vincent SP998 on eBay and converted it to this VFET build, all 32.5kg of it. Perhaps a bit overdone but definitely worth it!
Martin
Sent from my HTC 10 using Tapatalk
Martin
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
Sent from my HTC 10 using Tapatalk
I finished my build a month ago. Since then, every time I listen to music, I'm astonished by the sound this amp is producing. AlephX that I used before was great but this VFET amp is completely a different league. So much clarity and spaciousness in the sound, incredible. Some pictures of the build are attached. I found an empty new box for Vincent SP998 on eBay and converted it to this VFET build, all 32.5kg of it. Perhaps a bit overdone but definitely worth it!
Martin
Sent from my HTC 10 using Tapatalk
Wow, look so great! Congratulation!
Your amp look like computer case🙄