Of course in fact lots of people says those things ¨speed up things¨, what I have seen is that this sometimes causes HF ringing or oscilations, in some cases this can be heard but it aint a improvement at all, maybe thats why some people even recomend to do it in every capacitor present passing audio or not, just because they can hear a change it doesnt mean this should be made
It has been done without any reports of problems, recommended by bernd ludwig. Just wondering if the little 0.1uf caps are necessary with the big 100uf electrolytic.
Small 0.1 uf film caps on the amp board, one for each rail, so two in total:
Quote: " Decoupling the power-supply-rails on each PC-board not only with 100nF but with
100uF might reduce resonance-effects due to the inductance of the wires from the
PS as well as mutual interference between the channels via PS. Add one 100uF (or
220uF)/100V across C15 and one across C16, this will be more effective than
rewiring the whole PS! "
Quote: " Decoupling the power-supply-rails on each PC-board not only with 100nF but with
100uF might reduce resonance-effects due to the inductance of the wires from the
PS as well as mutual interference between the channels via PS. Add one 100uF (or
220uF)/100V across C15 and one across C16, this will be more effective than
rewiring the whole PS! "
100nF decoupling capacitors as typically used in digital circuits are great for suppling current pulses in the 10 to 100Meg Hz ranges of transients. You don't even need to have them close to where you are consuming the current as a 1ps rise time edge can be effectively decoupled upto 8 inches away. Read Howard Johnson for more info.
Tldr...100n on the power supply won't hurt or even be felt by audio.
Tldr...100n on the power supply won't hurt or even be felt by audio.
Thanks! That's what i feel as well that bigger caps are required but everyone uses 0.1uf so i was pushed on by peer pressure.
What do you think is the ideal cap size at this position, i'm thinking even the 100-200uf mentioned is too small to stabilize the amp when big bass currents are needed to be reproduced at high volumes
Thanks! Do you mean stick with the 100-200uf as recommended by bernd ludwig, or the stock 0.1uf
Certainly Ludwig's article has everything you need to know in it. He mentions the 100nF caps in the same breath as the wiring. Bonsai's article on wiring on Hifisonix.com will be a great help for you.
In summary, if in doubt, fit the 100n and enjoy.,
In summary, if in doubt, fit the 100n and enjoy.,
Apart from the op-amp is there anything on this board that you would be tempted to change.
I’ve read reviews and seen youtube videos in which people are saying the output transistors are fake, that it is difficult to purchase all the components, solder them down, include the labour charges and profit margins, and then ship out for 25 quid per pair of boards, they may be cutting corners.
Assuming the components could be fake what do you think about changing the components in the signal pathway, there is the input filter consisting of a cap rated at 1uf and a 22kohm resistor.
What would you change, which components do you think are important and would have the most effect on potentially improving sound quality.
I’ve read reviews and seen youtube videos in which people are saying the output transistors are fake, that it is difficult to purchase all the components, solder them down, include the labour charges and profit margins, and then ship out for 25 quid per pair of boards, they may be cutting corners.
Assuming the components could be fake what do you think about changing the components in the signal pathway, there is the input filter consisting of a cap rated at 1uf and a 22kohm resistor.
What would you change, which components do you think are important and would have the most effect on potentially improving sound quality.
I think there are bigger chances to find counterfeit TO3 (Mj ones) and 2SA/SC transistors than these ones:
So you think the components are good to go, has any measuring been done or is it a visual inspection
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Have you changed any components and noticed an improvement in audio quality. There are reports of changing the input cap and resistor with sound quality improvements. Any thing that may be worth looking at Thanks!
Would an easier way to reduce the input sensitivity be to increase R3 at the input to 33k ohms, from the stock value of 22k ohms
I'm getting a harsh brittle treble which i heard is something to do with the op-amp or the circuitry around it. Have changed the opamp to lm49710 but the problem persists
Thanks!
I'm getting a harsh brittle treble which i heard is something to do with the op-amp or the circuitry around it. Have changed the opamp to lm49710 but the problem persists
Thanks!
What schematic are you refering to? Lowering the gain of the first stage is a good thing as recommended by Bernd Ludwig.