The idea of an external power supply is vary appealing to me. In theory, it will reduce both noise and heat inside the amplifier, and increase space. I wanted to know if anyone has done an external power supply for a Pass amplifier, and how it went?
plenty of examples
Boyz are building external PSU, serving several different amps, depending of mood
It can be better, and certainly helping in Cheapskating
don't forget that final C bank must be in same case with amp pcbs
Boyz are building external PSU, serving several different amps, depending of mood
It can be better, and certainly helping in Cheapskating
don't forget that final C bank must be in same case with amp pcbs
Not just grounding, but having a short current path to supply the output stage of the amp. Speaker returns (black) are best connected to the last bank of capacitors.
Pass DIY Addict
Joined 2000
Paid Member
Here is my external psu
I use it to power my F4, M2, and Aleph-J amps. I tend to run hotter amps in the winter and cooler amps in the summer.
I use it to power my F4, M2, and Aleph-J amps. I tend to run hotter amps in the winter and cooler amps in the summer.
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Hmm, the link doesn't seem to work for me. Or at least, I can't find a picture of your PSU on that page or any of the neighboring pages.
Or just for having big cans in amp-case (washing m
🙂 )Sorry.
But! One thing that keeps itching me with external power-supplys is the power-switch. Depending on where the 2 chassis will be placed, it could be comfortable to add additional connections to the umbilical so that the power-switch would be in front of the device instead of somewhere (on the PSU)...
Here is my iteration of FW M2 with separate PSU. Power switch is at psu.
https://www.diyaudio.com/forums/pass-labs/281520-official-m2-schematic-243.html#post5341421
T'is my main amp for 3years now.
cheers
A.
https://www.diyaudio.com/forums/pass-labs/281520-official-m2-schematic-243.html#post5341421
T'is my main amp for 3years now.
cheers
A.
Pass DIY Addict
Joined 2000
Paid Member
You might need to be logged in for the link to work properly. Also, images don’t display unless you are logged in. The only real reason that I used discrete diodes is that the diode board they are mounted on came with the cap board that I purchased from forum member Tea-Bag. So, I just used what I had. Some time ago, I purchased a whole tube of diodes, so I just used them here, too.
It has worked well for years now and is plenty power any of the first watt amps. I have a number of old tube radios that I’ve restored, so I built it bread board style.
Or just for having big cans in amp-case (washing m
Sorry.
But! One thing that keeps itching me with external power-supplys is the power-switch. Depending on where the 2 chassis will be placed, it could be comfortable to add additional connections to the umbilical so that the power-switch would be in front of the device instead of somewhere (on the PSU)...
switch - put it on front of PSU case
no need for unnecessary complications
though, mains relay or solid state relay ....... easypeasy to deal with
I ran 4 wires, 3 for the bipolar power supplies and 1 for chassis. Both chassis tied the power supply ground wire to chassis ground with a thermistor. Not sure if it was necessary but I sleep well. Then I have a remote feed from my preamp tied to a power filter with a delay that feeds power to the power amp power supply. My preamps power up with a infrared remote then preset delay and amps power up.
Bill
Bill
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I'm going to show my ignorance here... What are the three wires? You already have a fourth ground wire. What's the shared third wire?
Hi! I read Solid State Relay or SSR. Don't ever use a zero crossing type for switching transformers. Just don't.
Bipolar power supply 3 wires + 0 - and the forth is chassis ground. In practice you will sometimes tie the 0 to ground with a thermistor. The two chassis would be tied to each other through the thermistor if you did not use the fourth wire.
Bill
Jean-Paul
Are you saying to not use zero crossing SSR with linear power supplies?
Bill
Jean-Paul
Are you saying to not use zero crossing SSR with linear power supplies?
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