Another Aleph5

It's alive .... :cool:

Finished my new Aleph5 today, as I sit here listening to Clapton Unplugged.

The attached pic is from the "bench run" and I'll post some more images to a webpage in due course.


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These are 300mm x 150mm with Rt = 0.25C/W at 80C

Cost = $AUD78 for Two (ie. about $US20 each!!!)

The company in Oz who manufactures/sells these is particularly helpful and I would recommend them to anyone.

Julian Wales
Conrad Engineering
36 Victoria St
Brunswick East VIC 3057
Ph: (03) 9387 7106

This afternoon I ran the amp for about 5 hours straight. Didn't measure the temp (I will) but the sinks were a little warmer than I would like :(

cheers, mark
From the above:
W.O.L.F.: How long are the fins of your heatsinks?
See page #7 of the following PDF file for all data:

Anthony Holton: Are you still running your web site as I need the new URL for it?
Yep. As a side-line I do a couple of websites for work-related stuff. They felt sorry for me and bought me an ADSL connection, so I have moved ISPs and am in the process of re-doing the whole website (which will include all details of the above adventure in due course).

This will find the home page and the amp stuff will be under the directory ../passlabs/

Rodd Yamashita: Super job as usual. You do set the standard.
Thanks for that, but I also firmly believe in credit where it is due, and a significant part of the inspiration for this came from Wayne's materpieces:

I looked at these mono's then back at my Aleph4 and felt a little embarrassed ;)

The other part of inspiration of course came from listening to my Aleph4 .... thanks NP!

Sound? ..... just fine, thanks very much. Have a slight hum and may well add some Pi inductors .... means I lose those nice brass bus-bars ... lets see, "looks vs sound" ..... not really a contest, eh!

cheers, mark
Very nice indeed.

I wonder how the sound compares to your Aleph 4. Reading Pass literature I was under the impression that bigger Alephs supposedly sound better. I still didn't decide if in one chassis I should build Aleph2 mono, or go for stereo Aleph5 and biamp.

If you've seen my Toaster Aleph 5 monoblocks the heatsinks are 30x20 cm with 2cm fins and I use 2 per channel, but they not enough. I biased the amp 2/3rd original value and the temp is still around 55deg C. I also got some hum (56,000u capacitance, no chokes). Strange, the hum is much bigger in one channel, but it almost totally goes away when amp is hot.