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FS Power Physics A-404 400 watt Class-D modules

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Couple questions...

Got the modules...do these have + and - 15V or just +15V? Your attachment shows just +15V.

The speaker outs are the spades, correct? Do you know which one of them is the + out (J4 or J5?)?

The labeled + / grn / - is the balanced input?

Any info on the other connector block below the power connector?
 
The boards require only +15v and + 5v & - 5v and then of course +70V

The spades are the speakers correct. Not sure which is + or -. And yes the other wires are the balanced inputs. The other plug I think is an accessory plug but I have no info on it. I sent an email to PP but got no response.
 
Got my module today, and have two significant wonders:

Your printed paper shows GND on the end, pins 1 and 2, with +70V on pins 3 and 4. There is, however, continuity between pins 3 and 4 and GND2, where GND2 is the shield of the balanced input and also the plated holes for mounting. It is almost certain that GND2 is actual 'ground'. This leaves the question as to whether the raw DC input is actually intended for a positive grounded supply (since pins 3 and 4 are internally connected to 'ground').

So based on your diagram, we apply the common of the 15 and 5V supplies to pin 1/2, and the negative of the 70V to pin 1/2, positive to 3/4. Then 3/4 is effectively earthed to chassis by the pcb. This is most unlikely, since it will elevate the 15 and 5V supplies to -70V above earth. How the analog front end can work with that is beyond me.

Just want to make sure about this before I energize and potentially blow it up. Hate to spend $50 on something and then destroy it due to incorrect wiring.

Second wonder is about heatsinking- I don't see provisions for bonding the board to a heatsink, which I was expecting. No problem if it isn't needed, but squeezing 400W out of 4 MOSFETS with no heatsink is quite the accomplishment, Class D or not.
 
Oh CRAP! I do have the GND and +70 pins reversed. On the power supply GND is labeled on top of +70V but there are white lines pointing to the pins which are reversed...crap crap crap!


The only heatsinking these modules had was a thin insulating strip of some kind of rubber under the mosfets. the module was otherwise mounted flat onto an aluminum plate! so I am assuming it doesn't need much.
 
Hope the following info helps as I was able to get some info specifically on the A-404 boards. I have a prototype DEQX amp that was built with 6 of these amp boards.

Unfortunately, I blew the SMPS that was running the boards and one day, I might get into it to try to fix it as these boards run a clean signal.

in any case, albeit late, here is some documentation on these boards specifically.
 

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