I imagine that this would be just as valid a question as feeding the 100W/Ch beast with batteries. The external PSU will be fully CLCC smoothed.
Disconnect the amplifier PCB's from the power supply - this should be easy. In other words, isolate the transformers, rectification and DC rail smoothing.
Does the fuse still blow open? Let us know...
Does the fuse still blow open? Let us know...
I've just bought 12 x 22000uF 63V caps for the beast but even though they are 105C caps they only state 10000 hours of life. I'm going to go for an external PSU to keep them away from the roasting heat of the Aleph 4. The Aleph is a real beast but it does sit at about 50C.
No-one has answered my question. The main PSU is 1000VA with 12 x 22000UF CLC filtering. The power amp will need local decoupling. What would you recommend in the amplifier enclosure.
The supply may seem solid with no load but will sag around 2-3V once loaded - hence, maybe consider a SMPS.. the ACA's power supplies are outstanding, two of them can produce +24 / -24V; the sag will be few millivolts once loaded even with 4 A of a constant draw. The ground lug will have to be lifted on both supplies at the low voltage end, to get them working correctly for +24 / -24 config.
I believe in the shortest possible copper (or silver🙂) bus-bars' current distributon, straight from the capacitor bank, located inside the amplifier enclosure; so an outboard power supply gets thumbs down, but that's me...
Nothing wrong with Cornell Doublier caps; you can get MLytics if you want...
If you want to pursue an outboard power supply, do not use any "local" decoupling inside the Aleph 4. Aleph 4 has the local decoupling on the PCB. Do not change the value of this capacitor. This will have a large effect on sound if you change them... in some cases even oscillations/instability.
I believe in the shortest possible copper (or silver🙂) bus-bars' current distributon, straight from the capacitor bank, located inside the amplifier enclosure; so an outboard power supply gets thumbs down, but that's me...
Nothing wrong with Cornell Doublier caps; you can get MLytics if you want...
If you want to pursue an outboard power supply, do not use any "local" decoupling inside the Aleph 4. Aleph 4 has the local decoupling on the PCB. Do not change the value of this capacitor. This will have a large effect on sound if you change them... in some cases even oscillations/instability.
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get fractal design fans; very low noise, 12V DC models, run them at 10V and they'll be absolutely silent for years - they can be left ON indefinitely. Two of them will cool the interior very nicely + they will provide air flow around the heatsinks as well, to boost the heat dissipation; place them on top of Aleph 4, but lift them a bit from the top panel to allow some reflected air to flow across the heatsinks; they'll "wipe" the heat off the top of the heatsinks.
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The amp. has already got two fans fitted that flow air through the internals.
I'm collecting the parts to remotely mount the PSUs. I'm still waiting for someone to comment on local supply decoupling once this is done.
I'm collecting the parts to remotely mount the PSUs. I'm still waiting for someone to comment on local supply decoupling once this is done.
My Aleph 4 doesn't have any local decoupling. The only electrolytic is in the feedback loop.
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Sounds OK to me. After removing the transformers and the main PSU caps there will be plenty of space to keep the last caps cool.
I'm thinking about fitting an internal chimney in the hole the transformers leave behind. It will be open with grills at both ends with a silent fan. The caps can be inside the chimney so should be kept cool.
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The chimney with a small fan sounds like a good solution. Even the slowest speed on the fan (resistors can be used to slow it down) should move enough air to keep the new caps cool. Keeping the last bank of caps in your CLC or CLCC in the amp should work well. This mans that your outboard psu is either CL then unbilical or CLC then unbilical. If you need to rebuild in the future for similar reasons, replacing just the few caps that are inside the amp will be less expensive.