What have I built? - diyAudio
Go Back   Home > Forums > Amplifiers > Pass Labs
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Pass Labs This forum is dedicated to Pass Labs discussion.

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Thread Tools Search this Thread
Old 13th January 2005, 07:53 PM   #1
diyAudio Member
Join Date: May 2002
Location: oz
Default What have I built?

HI all

After much stuffing around , misunderstanding, and generally not knowing what I'm doing,, I've managed to build a version of an Aleph AMP,
It was Intended to be an A5, using some left over parts but most notably as some may have noticed in other threads, some undersized and Fan cooled heatsinks.

In short at the end of the day its spec's are essentially as follows:
Supply Voltage +-36V from 50VCT 50A trafo
PS caps 4 X 80KuF
Reduced bias to keep thermal trips on hetsink adjacent output itf240's -I have 0.36V across 1 ohm resistors attached to irf240's (A5 should be 0.6V accord to schematic)
Total 6 mosfets per channel.
IRF240 case temperature 59deg C stabilized (at last)
offset about 50mV

I think others out there know the math to work out what power output I can expect and I would be greatful for any comment.

Have I built a mini Aleph??

BTW it sounds great! (is being used in a triamp system as a mid -range amp and I have also tried it full range- very nice indeed)

Cheers and thanks in advance
george a
  Reply With Quote
Old 13th January 2005, 08:18 PM   #2
cowanrg is offline cowanrg  United States
diyAudio Member
cowanrg's Avatar
Join Date: Apr 2002
Location: Lafayette, CO
Send a message via AIM to cowanrg
sounds kinda like an aleph3 maybe? maybe a 30?
  Reply With Quote
Old 13th January 2005, 08:47 PM   #3
diyAudio Member
metalman's Avatar
Join Date: Jun 2003
Location: Victoria, BC, Canada
Did the off-the-cuff calc's, and it looks like you have approx. 20W into 8ohms and 10W into 4 ohms. Your amp's power output is current limited across the impedance range at this point, giving you more or less a MiniA.

If you can find a way to improve your cooling (bigger heatsinks or add a fan, etc.) you could increase the bias. Based on your trafo rating, with increased bias you could upgrade to somewhere between an Aleph3 and 5.

Cheers, Terry.
  Reply With Quote


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
Who has built their own? markp Solid State 43 3rd August 2014 09:10 AM
Hi! And I built one too... The RB Chip Amps 4 13th March 2009 09:12 AM
i built these a while ago and roystr Full Range 11 10th November 2005 12:49 PM
Anyone built this amp? JojoD818 Solid State 26 19th August 2003 11:32 AM

New To Site? Need Help?

All times are GMT. The time now is 09:54 PM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2