I just did that today impressive low noise!
But those cheramic input caps destroy the sound a little.
Is it stupid to bridge them?
If I understood them I could.
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I have no clue. Every serious power amplifier I have own so far did not sport any potentiometers on its input.
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On a whim, I ordered the $50 SMSL amp mentioned before and was quite impressed with the sound quality out of the box. No extensive testing, but it’s hard to argue against that kind of value.
Solve, what does your end result look like If I may ask?
I see C3 1uF in tA1s schema before the OP-amp.
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TNT, I forgot I made a post detailing a minimal effort mod...
https://www.diyaudio.com/community/threads/infineon-ma12070-class-d.347422/page-49#post-7085634
I would also suggest changing the 4x 10k resistors to a lower value, like 1-2k. You can salvage a couple of the 22k resistors and replace the 2x 10k resistors used for the 1/2Vcc voltage divider. They aren't in the picture; just follow the trace of the lower left 22k resistor.
https://www.diyaudio.com/community/threads/infineon-ma12070-class-d.347422/page-49#post-7085634
I would also suggest changing the 4x 10k resistors to a lower value, like 1-2k. You can salvage a couple of the 22k resistors and replace the 2x 10k resistors used for the 1/2Vcc voltage divider. They aren't in the picture; just follow the trace of the lower left 22k resistor.
I will except for keeping the "fuse" that "increases the noise and scratchiness around mid volume" thingy 😉
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Yes. And if you want to go one step further, bypass the 4x 2.2uF ceramics at the top with quality 1uF film caps. It's a tight space to work with, but it can be done.
If you don't want to replace the pot, maybe change the 22k resistors marked in blue to 8k or even the salvaged 10k would be better. 22k is a little too high to properly "law fake" a 50k linear pot.
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As I will use this only above 1k I might exchange 2,2uF ceramics with 200nF film... if it could be cramped in there....
If I where to remove the pot all together do I need to replace it with resistors somehow or just connect the input to next stage/further?
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If I where to remove the pot all together do I need to replace it with resistors somehow or just connect the input to next stage/further?
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So, I have had my BRZHiFi running as delivered for a couple of days. Its being power fed by a Meanwell RS-15-15 tuned to 19V. It drives only my 16 ohm compression driver set to cover 1400Hz ->
I have read about the "spaciousness" impression reports and I have to agree - it is a bit different in this sense. I wonder how that can be?
In general I like the sound - perhaps the best I have had for my WGs. It does exhibit some noise but not so much that I can hear it easily from my listening position. Its a fine amp I have to say. NB - I utilise very little power and nothing in the bass.
Anyways - I'm about to do these mods now:
Wish me luck 🙂
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I have read about the "spaciousness" impression reports and I have to agree - it is a bit different in this sense. I wonder how that can be?
In general I like the sound - perhaps the best I have had for my WGs. It does exhibit some noise but not so much that I can hear it easily from my listening position. Its a fine amp I have to say. NB - I utilise very little power and nothing in the bass.
Anyways - I'm about to do these mods now:
Wish me luck 🙂
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Yes you lower the noise with those mods.
Change the input caps to bigger like 4.7uF and you get the bass.
And I agree with that space these chips have.
My guessing it's very even in the channels in frequency with good crosstalk.
Change the input caps to bigger like 4.7uF and you get the bass.
And I agree with that space these chips have.
My guessing it's very even in the channels in frequency with good crosstalk.
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Work ESD safe or you will have only a PLOP once. Ground yourself and do not wear synthetic clothing while working on ESD sensitive stuff. Use cheap test speakers after working in the amplifier.
I read you have an issue with ceramic caps but be assured these are necessary with this chip. If you bridge them with 2.5mm pitch film caps make sure you have short lead wires. I think it only works out for the input caps. Think "smallest possible film caps with short wires" and only then brand, type etc.
The resistors come off way more easy when using 2 soldering tools which also function a pliers then aka "Chinese chopstick method" as I call it.
I read you have an issue with ceramic caps but be assured these are necessary with this chip. If you bridge them with 2.5mm pitch film caps make sure you have short lead wires. I think it only works out for the input caps. Think "smallest possible film caps with short wires" and only then brand, type etc.
The resistors come off way more easy when using 2 soldering tools which also function a pliers then aka "Chinese chopstick method" as I call it.
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