After month of regular vfet amp session he become completly burn-in.
I am amazed by the fact this Sony 2SJ/SK was in Hong-Kong little unknow for long time
and today they are all out of stock, run hot and amplify the music around the world. New life
Thanks and good night Gyuri
Best regards
Fresh, airy, and tight at the same time, with the inseparable tintinnabuli.
And it gives new meaning to the term: Microdetails.
Yes, even without red wine. 😎
And it gives new meaning to the term: Microdetails.
Yes, even without red wine. 😎
It's like Bach, babbling like a brook, it flows like a river and a fiery flood as fretfulness ocean.
It is just for your mood, soundhappy! 😉
It is just for your mood, soundhappy! 😉
I have given this name to my amplifier:
Closer to the Music.
closer to the music Vol.4
Folks at Stockfisch Records also knows something for sure.
Closer to the Music.
closer to the music Vol.4
Folks at Stockfisch Records also knows something for sure.
Yes Gyuri 😀
You pointed Caddock MP915 can be interesting to use in R5 & R6 position....
i build this one with fews new to me resistors :
Texas Company Components , Vishays bulk foils...let's give a try.
Do is worst ? Anyway is fun 🙂
Detailed DC measurements:
left: right:
T6 to T7 = 1.6260 T6 to T7 = 1.5630
T8 to T9 = -1.6140 T8 to T9 = -1.5680
T7 to T10 = -2.024 T7 to T10 = -2.041
T9 to T12 = 2.063 T9 to T12 = 2.019
T6 to T11 = -6.807 T6 to T11 = -7.025
T8 to T13 = 6.742 T8 to T13 = 6.933
G to T2 = 24.52 G to T2 = 24.52
G to T6 = 29.43 G to T6 = 29.35
G to T8 = -29.32 G to T8 = -29.20
G to T14 = 13.980 G to T14 = 13.970
G to T15 = -14.000 G to T15 = -14.000
G to T17 = -7.399 G to T17 = -7.416
G to T19 = 9.689 G to T19 = 10.076
G to T16 = 8.201 G to T16 = 8.164
G to T20 = -9.205 G to T20 = -8.806
G to T10 = 25.72 G to T10 = 25.72
G to OUT= -1mV G to OUT= 1mV
G to T18 = 1.1720!! G to T18 = -0.860!!
V+ =29.9 V+ =29.9
V- =29.9 V- =29.9
left: right:
T6 to T7 = 1.6260 T6 to T7 = 1.5630
T8 to T9 = -1.6140 T8 to T9 = -1.5680
T7 to T10 = -2.024 T7 to T10 = -2.041
T9 to T12 = 2.063 T9 to T12 = 2.019
T6 to T11 = -6.807 T6 to T11 = -7.025
T8 to T13 = 6.742 T8 to T13 = 6.933
G to T2 = 24.52 G to T2 = 24.52
G to T6 = 29.43 G to T6 = 29.35
G to T8 = -29.32 G to T8 = -29.20
G to T14 = 13.980 G to T14 = 13.970
G to T15 = -14.000 G to T15 = -14.000
G to T17 = -7.399 G to T17 = -7.416
G to T19 = 9.689 G to T19 = 10.076
G to T16 = 8.201 G to T16 = 8.164
G to T20 = -9.205 G to T20 = -8.806
G to T10 = 25.72 G to T10 = 25.72
G to OUT= -1mV G to OUT= 1mV
G to T18 = 1.1720!! G to T18 = -0.860!!
V+ =29.9 V+ =29.9
V- =29.9 V- =29.9
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G to T14 and T15 is ~50% of the rail voltage. That's good, and as expected.
G to T18 can be zeroed during the test with very small adjustments of P3, but it's not that critical.
G to T18 can be zeroed during the test with very small adjustments of P3, but it's not that critical.
Thanks!
You know, what I don't like, T16, T17, T19 and T20.
I don't know, these value are depending on parameters on VFET or not.
I'm told it several times, I'm not an EE mind.
Maybe I have only a two bit logic. 😉
You know, what I don't like, T16, T17, T19 and T20.
I don't know, these value are depending on parameters on VFET or not.
I'm told it several times, I'm not an EE mind.
Maybe I have only a two bit logic. 😉
Those specific test node measurements have a very wide range of acceptable.
Your measurements are good. 😀
Your measurements are good. 😀
Thanks again!
Anyway, if I can understand it correctly, I can set anything to anywhere, while I can maintain 100mV across R32.
Right?
Anyway, if I can understand it correctly, I can set anything to anywhere, while I can maintain 100mV across R32.
Right?
Hi Gyuri,
The way I see it, the main things are to get T18 close to 0, while getting voltage drops across R5 and R6 near 1.5V and drop across R32 around 100mV when your amp
is warmed up. The final values for T16 - T20 I think will depend on your vfets
so I wouldn't worry too much about them.
Cheers,
Dennis
The way I see it, the main things are to get T18 close to 0, while getting voltage drops across R5 and R6 near 1.5V and drop across R32 around 100mV when your amp
is warmed up. The final values for T16 - T20 I think will depend on your vfets
so I wouldn't worry too much about them.
Cheers,
Dennis
If I have not yet told to you, my balanced, dual BA3 pre driven F4 amp for Eminence 18"s,
it is a very good companion for SONY VFET amp.
it is a very good companion for SONY VFET amp.
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Now, I must go out with my cat.
Brrr. It is cold and dark outside.
Perhaps I will see something other than visual snow.
Brrr. It is cold and dark outside.
Perhaps I will see something other than visual snow.
My BOSOZ now drives directly Sony VFET amp, rather than my Behringer Super-X Pro CX2310.
So it drives now Sonidos+Mark@Daniel DM-4 AMT on all frequencies.
I'm sure it is a big improvement in sound quality even at bottom frequencies.
Behringer drives 18" Eminences as earlier with a little help of balanced BA3 driven F4 amps.
However it gives me more freedom to chose x-over frequencies and levels on.
So it drives now Sonidos+Mark@Daniel DM-4 AMT on all frequencies.
I'm sure it is a big improvement in sound quality even at bottom frequencies.
Behringer drives 18" Eminences as earlier with a little help of balanced BA3 driven F4 amps.
However it gives me more freedom to chose x-over frequencies and levels on.
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