Prasi,
So bill of materials for Eric's PCB is the same as what was updated on this post?
https://www.diyaudio.com/forums/sol...-amplifier-designed-music-75.html#post5547417
It is ok to assume that parts listed here will fit in the PCB. I am asking because you made the PCB slightly smaller than before.
Obviously yes. A bit of homework would reveal that they (Eric's pic, the bom and stuffing guide ) all mention single pair o/p.
I have 1 pair left if anyone is interested. Pic, see post 790.
$3 usd for a pair + price of padded envelope + shipping
I can ship during week of Oct 8
Thanks
Eric
Eric,
Another member had asked for a pair in the following post:
https://www.diyaudio.com/forums/sol...-amplifier-designed-music-80.html#post5559679
with reference to design posted in post no. 775, I wanted to check fitment and ease of soldering , here is how it all looks in 3D. Provided finalized resistor pads for trimmer as per Mooly's suggestion and also managed to squeeze in 15mm pitch film cap for the input ( MKS4B051004J00KSSD WIMA | Mouser India ).
Attachments
I recall that the gate resistor values are a bit different between the new and old, not a large amount.
Can hunt around in hafler threads and find something if you are motivated.
Can hunt around in hafler threads and find something if you are motivated.
I have now reverted to the original configuration (albeit with reduced gain using 22K and 1K feedback resistors). I made some other changes to my system (incuding removing all the "Qausimodo" snubbers - but that's another story) and feel that I prefer the open and dynamic sound of the original to the slightly "niceified" effect that the nested feedback has. Definitely worth a try though - nothing ventured, nothing gained!
Thanks for the feedback (😉)on that Dave, its always good to hear subjective opinions on these things.
Hugh,
The snubbers I removed were C-RC snubbers across each secondary of the mains transformers. The philisophy behind this can be found in the Quasimodo thread:
Simple, no-math transformer snubber using Quasimodo test-jig
It's funny how the mind is pleased by tweaking a pot and observing a 'scope trace for the "perfect" resistor value which will kill all the switching noise. I was convinced that this had to result in better sound so I went through my entire system adding snubbers... but after a while I realised that some female vocals had some sort of colouration. This was most noticeable with for e.g. Alison Krauss and Patty Griffin, when the vocals soar up they also tended to harden up. It's a similar sonic effect to lens flare with cameras.
Anyway... long story short... removing each snubber improved this and also made a distict improvement in clarity and tonal balance - this is why I originally thought the Mooly amp was a bit bright.
Just another cul-de-sac amongst the hundreds I've bumbled around in during the course of this daft but mostly harmless hobby 😀
The snubbers I removed were C-RC snubbers across each secondary of the mains transformers. The philisophy behind this can be found in the Quasimodo thread:
Simple, no-math transformer snubber using Quasimodo test-jig
It's funny how the mind is pleased by tweaking a pot and observing a 'scope trace for the "perfect" resistor value which will kill all the switching noise. I was convinced that this had to result in better sound so I went through my entire system adding snubbers... but after a while I realised that some female vocals had some sort of colouration. This was most noticeable with for e.g. Alison Krauss and Patty Griffin, when the vocals soar up they also tended to harden up. It's a similar sonic effect to lens flare with cameras.
Anyway... long story short... removing each snubber improved this and also made a distict improvement in clarity and tonal balance - this is why I originally thought the Mooly amp was a bit bright.
Just another cul-de-sac amongst the hundreds I've bumbled around in during the course of this daft but mostly harmless hobby 😀
Thanks Dave!
Very interesting comment on the snubber. I take this on board, your assessments are valuable to me.
Hugh
Very interesting comment on the snubber. I take this on board, your assessments are valuable to me.
Hugh