30Vac secondaries are way too high, for pcbs on pics
those are good for maybe one output pair, so no more than 18Vac secs
now, if building bigger, mulltipair Aleph, with 30Vac secondaries (750VA is respectable and appropriate), these pcbs aren't adequate for use with daughterboard arranging multipair mosfets, simply because there is no current capability of traces between upper and mosfet nodes on pcb
doable, if you introduce augmenting copper traces to carry necessary current - best using solid core wire soldered on top of traces, and adequate termination of wires on pcb itself
those are good for maybe one output pair, so no more than 18Vac secs
now, if building bigger, mulltipair Aleph, with 30Vac secondaries (750VA is respectable and appropriate), these pcbs aren't adequate for use with daughterboard arranging multipair mosfets, simply because there is no current capability of traces between upper and mosfet nodes on pcb
doable, if you introduce augmenting copper traces to carry necessary current - best using solid core wire soldered on top of traces, and adequate termination of wires on pcb itself
@vinay : Welcome back!
Some random thoughts:
I seem to recall there were small 'output boards' for the BrianGT PCBs, for mounting parallel output devices. Please keep in mind ZM's comments about the current capability of the boards.
Always great to see some Plitron transformers, which sadly are no longer available. 2x30 secondaries will get you a large-ish Aleph (60W range?) so count on large heatsinks. I suggest you look at the Aleph 60 as a reference (both the schematics and mechanical stuff)
IRFP240 is a pretty standard part to use in the Aleph. You'll need to match them to run in parallel. Please have a look here: https://www.firstwatt.com/wp-content/uploads/2023/12/art_matching.pdf
Papa mentioned some Aleph mods here: https://www.diyaudio.com/community/threads/the-aleph-design-reloaded.267857/#post-4184920
Have fun with your build.
Some random thoughts:
I seem to recall there were small 'output boards' for the BrianGT PCBs, for mounting parallel output devices. Please keep in mind ZM's comments about the current capability of the boards.
Always great to see some Plitron transformers, which sadly are no longer available. 2x30 secondaries will get you a large-ish Aleph (60W range?) so count on large heatsinks. I suggest you look at the Aleph 60 as a reference (both the schematics and mechanical stuff)
IRFP240 is a pretty standard part to use in the Aleph. You'll need to match them to run in parallel. Please have a look here: https://www.firstwatt.com/wp-content/uploads/2023/12/art_matching.pdf
Papa mentioned some Aleph mods here: https://www.diyaudio.com/community/threads/the-aleph-design-reloaded.267857/#post-4184920
Have fun with your build.
I am beginning to think that adding wire to supplement the traced on the BrianGT boards might not be worth the effort and perhaps better of going with one of the newer projects. What i really want is something in the 50-60 watt range and that can use most of the parts I already have.
This was my very first Pass amp:
https://www.diyaudio.com/community/threads/my-good-old-new-aleph.56454/
Inspired by mefinnis, many thanks for it!
I've built quite a lot Pass amps after that, yet, perhaps it is my favourite.
It was originally an Aleph 4, then evolved to something Aleph 1.2 while it ended up that monster I like very much.
There is a review about Aleph 2 by Kin, I think I mentioned it earlier, it is so poetic and true:
http://www.audioreview.com/product/amplification/amplifiers/pass-labs/aleph-2.html
"Amazingly detailed and fluid. I find myself able to close my eyes and see the music which I was not able to do with the KSA250. If the music is discribing an medieval battle field, through the KSA250, you feel the cavaliars thundering and you see knights charging at their enemies in a storm of dust. With the Aleph 2, you see the knights charging, waving their swords,eyes wide open, you might even smell their sweat. But there is no dust storm. You might call that the weakness of these amps. As for me, I'll prefer to touch the flowers than to feel the thunder, any time."
My monster combines the benefits of Krell and Aleph, I think.
So go ahead, you won't be dissapointed!
https://www.diyaudio.com/community/threads/my-good-old-new-aleph.56454/
Inspired by mefinnis, many thanks for it!
I've built quite a lot Pass amps after that, yet, perhaps it is my favourite.
It was originally an Aleph 4, then evolved to something Aleph 1.2 while it ended up that monster I like very much.
There is a review about Aleph 2 by Kin, I think I mentioned it earlier, it is so poetic and true:
http://www.audioreview.com/product/amplification/amplifiers/pass-labs/aleph-2.html
"Amazingly detailed and fluid. I find myself able to close my eyes and see the music which I was not able to do with the KSA250. If the music is discribing an medieval battle field, through the KSA250, you feel the cavaliars thundering and you see knights charging at their enemies in a storm of dust. With the Aleph 2, you see the knights charging, waving their swords,eyes wide open, you might even smell their sweat. But there is no dust storm. You might call that the weakness of these amps. As for me, I'll prefer to touch the flowers than to feel the thunder, any time."
My monster combines the benefits of Krell and Aleph, I think.
So go ahead, you won't be dissapointed!
You might check this thread and try contacting rhthatchar. I think members have used these PCBs for large-ish Alephs: https://www.diyaudio.com/community/threads/classic-aleph-amplifier-for-modern-ums-chassis.379571/
something like this? the wires can only go into the solder pads and then jumpers from soldered from the wire to the mosfets?30Vac secondaries are way too high, for pcbs on pics
those are good for maybe one output pair, so no more than 18Vac secs
now, if building bigger, mulltipair Aleph, with 30Vac secondaries (750VA is respectable and appropriate), these pcbs aren't adequate for use with daughterboard arranging multipair mosfets, simply because there is no current capability of traces between upper and mosfet nodes on pcb
doable, if you introduce augmenting copper traces to carry necessary current - best using solid core wire soldered on top of traces, and adequate termination of wires on pcb itself
Is it worth the trouble?
- Home
- Amplifiers
- Pass Labs
- Back here after a long hiatus