Not sure what you mean.
And we did not change anything drastic from the original M2 OPS.
Maybe you should ask Nelson at the original M2 thread.
Patrick
And we did not change anything drastic from the original M2 OPS.
Maybe you should ask Nelson at the original M2 thread.
Patrick
Can be optimize or is good as is ?
I'm quite happy with 5w of Acamini ....single 24v 400ma bias , mini M2 with some reserve in A/B will be a dream, at last for me LoL
Thanks thanks to Patrick (EUVL) for such a great variation of the M2(OS). No unobtanium or expensive parts required either! 
THD in the range of class D amps but without any of the undesirable cold heatsinks 😎
0R56 for R13/14 gives about 1.4A of bias and matched 240/9240. I didn't have 3.3uF caps so used 1u film on top and 2.2u elytic below
🤣
THD in the range of class D amps but without any of the undesirable cold heatsinks 😎
0R56 for R13/14 gives about 1.4A of bias and matched 240/9240. I didn't have 3.3uF caps so used 1u film on top and 2.2u elytic below
This version is still local feedback and M2OPS is not in the feedback loop (post #26).
Once you include the OPS in the opamp feedback loop (post #24), the distortion will sink to opamp level.
But different sound.
Ideally you should use brass screws and also solder the screw head to the bottom side.
😉
Patrick
Once you include the OPS in the opamp feedback loop (post #24), the distortion will sink to opamp level.
But different sound.
Ideally you should use brass screws and also solder the screw head to the bottom side.
😉
Patrick
Not surprisingly, the above measurement corresponds to what we published before :
https://www.diyaudio.com/community/threads/complementary-power-mosfets.378024/post-6889027
https://www.diyaudio.com/community/threads/complementary-power-mosfets.378024/post-6888301
So if one is to go for the local feedback option, the ideal candidate for the MOSFET pair is 1SK3497/2SJ618.
Apart from much lower distortion, they also allow output swing closer to the rails, due to their much lower Vgs at bias.
Patrick
https://www.diyaudio.com/community/threads/complementary-power-mosfets.378024/post-6889027
https://www.diyaudio.com/community/threads/complementary-power-mosfets.378024/post-6888301
So if one is to go for the local feedback option, the ideal candidate for the MOSFET pair is 1SK3497/2SJ618.
Apart from much lower distortion, they also allow output swing closer to the rails, due to their much lower Vgs at bias.
Patrick
So this is only for the lucky ones who own such pairs as you wrote:
The truely complementary pair of MOSFETs 2SK1530 / 2SJ201 is now unobtanium.
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The truely complementary pair of MOSFETs 2SK1530 / 2SJ201 is now unobtanium.
//
We have secured a source for a few hundred pairs of 2SK3497/2SJ6182's.
We shall make them available once matching is completed.
And they have higher Yfs than 2SK1530/2SJ201.
Their "problem" has always been high positive tempco.
But that is taken care of in the M2OPS by the opto-biasing circuit.
Patrick
We shall make them available once matching is completed.
And they have higher Yfs than 2SK1530/2SJ201.
Their "problem" has always been high positive tempco.
But that is taken care of in the M2OPS by the opto-biasing circuit.
Patrick
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Not sure what it is.
But if you have no control over bias current, it is likely you will have thermal instability.
Patrick
But if you have no control over bias current, it is likely you will have thermal instability.
Patrick
My small flat is heated with elctrical radiators. This could double as one with the advantage that this makes music i.e. a happier life 🙂
May I ask one more thing - what cooling capacity do I look for in a stereo cabinet?
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May I ask one more thing - what cooling capacity do I look for in a stereo cabinet?
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