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:

http://www.users.bigpond.net.au/mefinnis/files/conrad_hs_flanged.pdf

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).

http://www.users.bigpond.net.au/mefinnis/

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:

http://www.passdiy.com/gallery/aleph2-p1.htm

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.