I just tried all 4 combinations for the 2 input generators, but it doesn't seem to work.
I would make it like a two stage.. first stage with the high-cut part of riaa between the legs...then folded over in the opamp.. with a local feedback there making the base part active.
You generators are canceling... so both legs are seeing the same signal. need to phaseshift one 180 degrees.
You generators are canceling... so both legs are seeing the same signal. need to phaseshift one 180 degrees.
Interesting concept.
Otherwise is it possible top create out of this a differential folded cascode with transimpendance RIAA? something to think about.
If I pass the hump to simulate the plain scheme I can try to work that around.
For the generators, they are out of phase.
I will try to look for it...if and when you have chance if I haven't found it yet and you have instead, please post it on here
Thaankkss
and it looks so interesting. Do you remember other details on the post? like title fo the thread?
I tried to google but I was unable to find anything related!
Maybe you can start here :Re: 2SK117 or 2SK170 input stage?Better use 2SK389 - Elso Kwak - Tweakers' Asylum
That is the same post I was looking at I think.
On that post there is a mention on page 6 that change the 3.9 Zener with string of diodes leads to same low noise and same sound quality.
So I figure out what the circuit was missing: the 3 LEDS.
Why is that I don't understand....but here it is....
On that post there is a mention on page 6 that change the 3.9 Zener with string of diodes leads to same low noise and same sound quality.
So I figure out what the circuit was missing: the 3 LEDS.
Why is that I don't understand....but here it is....
Attachments
I am in the meantime shaping out in my mind how masterpiece can be laid out.
These are my two cents feel free to comment.
I have noticed that it is very hard to design an MC stage with enough gain with relative simple circuit (except for paradise) or at least with the different circuits we explored so far I am sure there are better ways out there I simply don't know them.
Anyhow this latest circuit seems to be very suitable for a mc section with cascoded monolithic 2SK389 and a gain of 49dB roughly. I will have to find a way to make it fully differential though.
This stage followed by a passive differential 75uS time constant feeding masterpiece rev 7 with only n-ch with maybe one or two 2sk389 (if a gain of 35-40 dB can be reached out that way) with trans z rest of the RIAA in fully balance configuration.
This is my thought so far, thus a 2 gain stages with split RIAA which circles back out with the first disclaimer in my first post .
What do you guys think? Does this idea have the potential for being a very low noise and distortion mc phono stage?
These are my two cents feel free to comment.
I have noticed that it is very hard to design an MC stage with enough gain with relative simple circuit (except for paradise) or at least with the different circuits we explored so far I am sure there are better ways out there I simply don't know them.
Anyhow this latest circuit seems to be very suitable for a mc section with cascoded monolithic 2SK389 and a gain of 49dB roughly. I will have to find a way to make it fully differential though.
This stage followed by a passive differential 75uS time constant feeding masterpiece rev 7 with only n-ch with maybe one or two 2sk389 (if a gain of 35-40 dB can be reached out that way) with trans z rest of the RIAA in fully balance configuration.
This is my thought so far, thus a 2 gain stages with split RIAA which circles back out with the first disclaimer in my first post
.What do you guys think? Does this idea have the potential for being a very low noise and distortion mc phono stage?
just like I Said.. two stage...high cut between the legs and active feedback in the second op-amp stage... let the first stage run without the feedback, as the signal levels are so low the distortion would be fairly low, noise sort of highish. (if you use the LSK or SK fets. (interfet would be interesting and lower in noise)
second stage would then have the base shelf as a part of the feedback network..
what you would then have is a floating input. (not balanced) and a single-ended output. Performance would in my objective be good. (One shot is still a more novel circuit.)
two stage...high cut between the legs and active feedback in the second op-amp stage... let the first stage run without the feedback, as the signal levels are so low the distortion would be fairly low, noise sort of highish. (if you use the LSK or SK fets. (interfet would be interesting and lower in noise)second stage would then have the base shelf as a part of the feedback network..
what you would then have is a floating input. (not balanced) and a single-ended output. Performance would in my objective be good. (One shot is still a more novel circuit.)
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