Official M2 schematic

[2 picoDumbs]

Can I use a 3900uF capacitor for C3, in place of 3300uF? I have 3900uF in stock at the moment.

What are the range of values for C3?

3900uF should be fine.
I'm fairly certain the value used here is to provide a nice soft slow start up of the output stage. Anything between 2000uF and 4000uF should be fine.

 

[henryve]

Thanks pD.

The reason I asked is that it seemed to me that the cap also provided some form of bypass filter for the feedback mechanism, unless I am off base with that assertion.

 

[Zen Mod]

Moi having 4m7 there

 

[JPS64]

Last modifications.

JP

 

[chede]

Is there a recommendation for film capacitors in parallel to electrolytic ones?

JP

Hallo JP,

I really like WIMA MKP10. Usually use them as signal path caps or bypass in signal path. When I can fit them, I put them in the PSU as well as bypass (often 2.2 µF - 4.7 µF). Otherwise, I try to use WIMA MKP4.

Both variants are large and need to be mounted directly on the PCB, though ...

Viele Grüße,
Claas

 

[JPS64]

Rectifier snubber is MKP2 PCM 5mm W < 4.5mm and 0207 resistor (22nF/400VDC + 4R7?).
Other ones, PCM 5, 7.5 or 10mm W < 6mm (MKP2).

Using MKP4 or MKP10 will need a 40mm longer board (up to 200mm).

Price differs marginaly,

Standby, waiting for decision.

JP

 

[2 picoDumbs]

Have you allowed space for these 3W bleed resistors?
https://www.digikey.com/product-det...nic-components/ERG-3SJ222/P2.2KW-3BK-ND/36811

 

[JPS64]

yes sir!

 

[JPS64]

... still waiting...

Example with MKP10 PCM27.5 on outputs.

See you monday...

Jean-Paul

 

[JPS64]

... film capacitors and additional input snubber added...

JP

 

[JPS64]

No more suggestions?

JP

 

[JPS64]

10 power supplies prototypes ordered and will be delivered in 9 days.

JP

 

[JPS64]

... and trying to finish finally amplifier...

Last one would be universal audio main filter (115/230VAC).

JP

 

[2 picoDumbs]

Some amp chassis come with split heatsinks, so you might want to orientate the mosfets differently.

 

[JPS64]

Standard version for DIY chassis allways existing.

It´s my own version, designed for custom made chassis.

JP

 

[2 picoDumbs]

Very nice

 

[Zen Mod]

source of shield case?

 

[JPS64]

TEKO 3710: Stahlblechgehäuse 54x50x19mm bei reichelt elektronik

pleaassseee...

JP

 

[Zen Mod]

tnx

 

[MASantos]

JPS64, will you be ordering extra amp boards? I might be interested in a pair if you do.