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First One - mosFET amplifier module

But Etna volcano is already alive! Luckily ...

Anyway thanks for the hints, :)



Catal... Please remind the words of LC "Guys don't be fooled with a small size of the First One modules possibly holding in your hands just now, got to know this: this is a very BIG amplifier considering sound signature, be prepared to be strongly surprised immediately after turning this little beast alive."

Mount Etna isn't a beast you want to wake up!...:)

(have fun!)
 
Sure, I'm joking!

Even if an earthquake releases a lot of power, you know ...
Few pounds perhaps are not enough :) :)

Last week I've tweaked my beloved Jvc Y5F tt.
Some plasticine here and there, some resin underside the ringing platter, an eva mat kindly offered by Ikea Catania, some teflon tape on sub weight and arm.
Now It's time to compare with his brother Y7.
Who will be the winner?

Frank
 
Heatsink Temperature

How high can the temperature go and where to measure.with FO ?Today I hooked up the FO with a simple PSU and not so big Heatsinks. After 2 Hours we reached 62C on the thick Part of the Heatsink where the Finns are,is that still ok?I shut it of then.Sound is good so far,very detailed even in Bass Area ,dead quite,wonder what`s gona happen with SMPS,if it`s really a big jump up.
 
i received four modules yesterday here in crete.

beautiful LC thanks.

they will go inside active speakers so what about grounding?

just heatsink connected to mains earth?

Hi

If the heatsink is the whole amp chassis bolted to back panel of the speaker, then yes, only heatsink connected to mains earth. GND from SMPS output goes to the earth bolt too, meaning all together two wires connected to this earth bolt. ;)

Regards, L.C.
 
How high can the temperature go and where to measure.with FO ?Today I hooked up the FO with a simple PSU and not so big Heatsinks. After 2 Hours we reached 62C on the thick Part of the Heatsink where the Finns are,is that still ok?I shut it of then.Sound is good so far,very detailed even in Bass Area ,dead quite,wonder what`s gona happen with SMPS,if it`s really a big jump up.

62 C is too hot too handle, your heatsink is way too small. Idle power dissipation should bring the amp heatsink to 46 C in a long term. Look for the heatsinks which have 0,4 K/W. What do you mean by SMPS big jump up?
 
FO arrived to Norway a few days ago. This is a nicely made diy-product you made for us Lazy cat!

I'm figuring out how to mate your amps to my coldamp sps80 psu. I have attached a picture modified from the coldamp manual. I have added a connection from input gnd on amps to earth on smps. In the manual it states: "Note that output GND is electrically isolated from mains and Earth". Does this seem ok to you?
 

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Edgar, look very carefuly and compare it to stereo connection sch from First One user manual and you will see they are 100% the same.

As we experimented with GND wiring for best results, my advice is to remove all three green wires and connect only main GND pin from SMPS to earth bolt. ;)
 
Edgar, look very carefuly and compare it to stereo connection sch from First One user manual and you will see they are 100% the same.

As we experimented with GND wiring for best results, my advice is to remove all three green wires and connect only main GND pin from SMPS to earth bolt. ;)

Agree, and please LC correct me if I am wrong, but I think it is better to have a star ground. To do it, it is better to link speaker GND together to PSU GND and PSU GND to amplifier GND.

Am I Right?
 
Agree, and please LC correct me if I am wrong, but I think it is better to have a star ground. To do it, it is better to link speaker GND together to PSU GND and PSU GND to amplifier GND.

Am I Right?

No, not in this case, speaker GND has to be connected on the First One module, mandatory.

In previous post I have explained correlation between GND and earth potential. Star GND has nothing to do with earthing and is already done on First One PCB.