They were all selected for same idss originally, hence the same RDS? Its better the top buffer fet to be a bit stronger than the one at its tail.
Salas did that earlier in this tread. Have to be 4,7 because it is a Zobel . Or use a electrolyt and no resistor ( 1,2 ohm)
In that case use a jumper for the 1,2 ohm
You don't need a jumper in case of 22uF/50V normal ESR electrolytic bcs I have provisioned it auto skips the resistor position.😉
4.7uF or 5uF only in case of MKP and the 1.2R populated.
Did you find a TT for a session yet by the way?
4.7uF or 5uF only in case of MKP and the 1.2R populated.
Did you find a TT for a session yet by the way?
No it is almost Christmas. People are busy. Next week A friend will bring a TT.
I am working hard on a power amp. And also the buffer . I am going to compare it with another one I made when it is finnished.
The Simplistic's natural class is low active parts count no overall NFB loop circuits. Apples to apples comparisons would be classic structure tube phonos and very few minimalistic SS. Even a Pearl is a stretch. To see what class of circuits sound someone prefers though poses no comparison limit.
Not another Riaa/ MC. Another buffer from Teabags GB. So I will compare two off the buffers with only smalll differences. Did not like the first I made.
You will need a 0.7V sensitive amp to have good dynamics from a unity buffer if the source is phonographic.
re: Q2x, Q3x, Q5x
I am not going to get 6 2sk117's with Idss between 3-4mA; in fact I'm not measuring any under 4mA. Assuming a spread from 4-6mA, which spots should have the "stronger" fets, which the "weaker"? I'm assuming a fairly strong one for Q2x is OK to boost the Vf of the LED's a bit; for Q3x and Q5x does it matter which has higher Idss?
Thanks.
I am not going to get 6 2sk117's with Idss between 3-4mA; in fact I'm not measuring any under 4mA. Assuming a spread from 4-6mA, which spots should have the "stronger" fets, which the "weaker"? I'm assuming a fairly strong one for Q2x is OK to boost the Vf of the LED's a bit; for Q3x and Q5x does it matter which has higher Idss?
Thanks.
Use your stronger for Q3X and 6.2K R3x. Use your medium for Q2x and 27R R6x. Your lower ones for Q5x.
I had a go at sorting my boards this morning swapping out the four leds and the output caps and reflowing a couple of joints.The phonostage is powered up;no smoke;and I have the following readings.
LEFT RIGHT
VDC 43 43
G/+rail 33.6 33.5
TP1/2 3.43 3.45
G/TP1 7.75 7.75
G/TP2 4.31 4.29
I'll it for a few hours to check things and hopefully will have a good result when I have a listen.
LEFT RIGHT
VDC 43 43
G/+rail 33.6 33.5
TP1/2 3.43 3.45
G/TP1 7.75 7.75
G/TP2 4.31 4.29
I'll it for a few hours to check things and hopefully will have a good result when I have a listen.
Thanks Salas. Now I notice the note on the BOM about the resistor values, and the alternates are in Teabag's excellent minikit. Sorry for the noise.
Only a little additional questional noise (new physics LOL) does no harm when aiding builders clarify the guides, still adequate SNR for vinyl replay.😀
Regarding the 47nf RIAA capacitor i found in ebay some Siemens rectangular polystyrenes with dimensions 12x12x12mm. I was thinking that i could solder these on the underside of the board. Is the extra lead length a problem in a Riaa?
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