Classic Aleph Amplifier for Modern UMS Chassis Builder's Thread

[celticray]

How would you size an inline EMI Filter for a Aleph Jzm?? 10 amps?

 

[roger57]

Generally those AC line filters are to prevent spurious signals from getting back on the AC line. Not required on analog amplifiers as they don't do any nasty switching. A good CLC, CRC or cap multiplier (which is what I use on Aleph J) work really well to filter your AC.

 

[6L6]

True, but they don’t hurt at all, filter the RF junk off the AC line, and score cool points.

A 30W aleph will only pull about 2A from the wall, so anything 3-4A or bigger will be sufficient. I usually buy 6A or 10A so they will work in whatever future project they might be reused into. Get whatever is in stock.

 

[Plott]

Hi All,
I´m just restarting my build soon, and would order the chassis - but there is some confusion (in my head...).
I´m building two Aleph 60 monoblocks, so which chassis would be suitable? I read here 4U - but 400, or 500? Or 5U400?
Many thanks in advance.

 

[rhthatcher]

A60 can be done in 2x 4u/300 deluxe

 

[ItsAllInMyHead]

For a pair of monoblocks, any of the above would work fine. I put two channels of an A60 into a 4U/500. It's certainly on the warm side, but nothing too hot. Splitting it into 2 4U/400 would be more than fine. A pair of 3U/400 would be fine.

Edited to add - Simul post from Randy....

 

[Plott]

Thsnk you both!
300? 🙈 is it for fearless smoke inhaler only or also for sissys?

 

[von Ah]

How does the thermal load get split between heatsinks? Plott, are you considering one heatsink per channel or two sinks per channel?

 

[Plott]

Two sinks per channel, one for the main board, the other one for the extension (or four, if it's a 400 or 500).
I think I will stick to a 4u400, with 3 FETs per sink (=12).

 

[6L6]

@von Ah The Classic Aleph is modular, so there’s a 2nd PCB that holds Mosfets on the other heatsink.

 

[von Ah]

Thanks, Jim. I was just looking at the board set, trying to reason that out.

 

[Plott]

Randy, I have now found your build of the A60 in 4u300.
Do you still use the amp regularly (because it's 2.5 years old)?
How is or was the temperature behavior and long-term durability?
I have my M2x in a 4u300, but it's an other, tamer animal.
Thanks in advance.

 

[rhthatcher]

I have been running my Aleph 30's daily for 2.5 years. I'm on the 3rd set of PCB's - first prototypes, then first GB rev, then the updated boards with additional rail caps. Temp is consistent, and long term reliability is also great.

 

[Plott]

Thanks Randy, sounds good - any experience with your Aleph 60's in the 4u300?
Would be much appreciated!

 

[rhthatcher]

Istvan - A60 in 4U/300 is warm and reliable. I had to hunt for my old post...