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First One - mosFET amplifier module

88 € for one channel, 176 for both, top quality parts, professionally assembled PCB, experienced designer, ca. 350 € to complete the whole amp. The SQ is in the many (ten) thousand € top league.:eek: This is the real power of the diy community. Congratulations Lazy Cat! :worship:

egra
 
Hi Danny

DPS-500/S-64 really looks like the right partner for the First One. Since it has regulated voltages it could assure even more output power/headroom than SMPS1200A400 I use here. Namely SMPS1200 is unregulated and gives +/-60 V on my mains and goes down to 58,5 V when fully loaded on 4 Ohms. DPS-500/S-64 would remain at +/-63 V ensuring very good dynamics and low ripple, if it has sufficient current capability. I don't have any experience with it, but it would be nice if someone would test it with the First One.

P.S. I just looked to datasheet and it is OK, 10 A steady output current with repetitive peaks to 16 A. :up:
 
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Hi Andrej,
Thx, I'll try them :)

What heatsinks are required for the First One with 3-4 ohm speakers ?

Regards,
Danny

I recommend any heatsink having 0,5 K/W or even lower. Idle dissipation of the First One is 30 W at +/-63 V, plus audio power dissipation easily adding extra 50-70 W, so 100 W all together to dissipate. 100 W * 0,5 K/W=50 K added to room temperature resulting in 75 C heatsink temperature. At that point silicon die in output transistor is around 100 C and that is somehow at max acceptability.

Look to Fischer Elektronik web page, model SK 157 or similar. ;)
 
Hi LC,
many thanks for what you said, about the DPS-500, in practice it is the reality of the facts.
I can only offer the version DPS-500/DA at + /-52V. for other versions, buy on the shop AudioPower, as many already know, I certainly agreements but is not managed by me.

Congratulations for the excellent design and engineering of the PCB. :up:

Regards
 
88 € for one channel, 176 for both, top quality parts, professionally assembled PCB, experienced designer, ca. 350 € to complete the whole amp. The SQ is in the many (ten) thousand € top league.:eek: This is the real power of the diy community. Congratulations Lazy Cat! :worship:

egra

Thanks egra :worship:

Amazing sound quality of this little fellow and bringing it to the DIY community is the one and the only thing why I started it all.

Regards, Lazy Cat :cheers:
 
LC, what is the lead time to delivery? Is this a pre-order?

Lead time is very dependent to Semelab's lead time, app. 12-18 weeks, again.

But there's no other way if we want to proceed with the project.

You can consider it as a pre-order to form orders waiting list, so this list will be taken into account who will get it first.


All informations needed, also regarding delivery times, will be regularly posted in post #1. :up:


:)