Rookie questions - diyAudio
Go Back   Home > Forums > Amplifiers > Pass Labs

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
Reply
 
Thread Tools Search this Thread
Old 8th September 2012, 09:02 PM   #1
diyAudio Member
 
Join Date: May 2012
Default Rookie questions

Hi,

I have a year off on my studies, and one of my goals is making some good diy hifi. Im not a rookie in electronics, since I already have a degree in electronic engineering, and have made a tube preamp and a dac some years ago.

I have some mini aleph pcb boards from chipamps.com that I have lost the parts list and documentation for. Is it possible to get this from some of you guys? And is this the aleph 30, or is it some other amp?

Second, I have access to some broken hifi equipment at work. I recently butchered a nad t773, with some rather huge torodials inside. The schematics are avaliable online, but does anyone know the exact specs on these? And what amp should I build with them?

I have tried to find answers online, but there is just so much info, I could not find exactly what I wanted.


Thanks!
  Reply With Quote
Old 8th September 2012, 09:31 PM   #2
diyAudio Member
 
Join Date: Feb 2009
it is most unlikely that you can use that transformer for any class A amp.
  Reply With Quote
Old 11th September 2012, 05:18 AM   #3
diyAudio Member
 
Join Date: Mar 2005
Location: Bakersfield Ca
The boards you have can be built as a mini aleph or aleph30 if you use the daughter boards. If you pm me your email address I will send you a spreadsheet for the parts bom, and the schematics. Be sure to check the 220uf caps polarities against the schematics one is backwards on the silkscreen on my boards. You will need a 18V transformer Brian still sells the power supply boards as well.

Bill
  Reply With Quote
Old 11th September 2012, 06:42 AM   #4
diyAudio Member
 
Join Date: Feb 2009
acctualy one can build any aleph with those boards.
aleph mini, aleph30, aleph5, aleph60, aleph2, aleph1.2. it is all the same regarding the front-end.
  Reply With Quote
Old 11th September 2012, 01:27 PM   #5
diyAudio Member
 
Join Date: Dec 2008
Quote:
Originally Posted by Jallhalla View Post
I have some mini aleph pcb boards from chipamps.com that I have lost the parts list and documentation for. Is it possible to get this from some of you guys? And is this the aleph 30, or is it some other amp?
Class A MOSFET amps sound very good.
However, understand the amount of power they will dissipate just sitting in idle.

Suggest buying a pre made case - make sure the heat sinks are large enough.

I'd say the Aleph j looks like the one to build.

With the high currents in the power supply, star grounding is important.
Many power supply articles don't mention this.

Here is a good article to read over.
Earthing (Grounding) Your Hi-Fi - Tricks and Techniques
.
  Reply With Quote
Old 11th September 2012, 03:43 PM   #6
diyAudio Member
 
Andersonix's Avatar
 
Join Date: Jan 2004
Location: Silicon Valley
Quote:
Originally Posted by AudioSan View Post
it is most unlikely that you can use that transformer for any class A amp.
Are you sure, AudioSan? MAYBE it has dual primaries, in which case one might wire them in series and get half the voltage?
  Reply With Quote
Old 11th September 2012, 03:53 PM   #7
diyAudio Member
 
Join Date: Feb 2009
yes i am sure. first of. you can only do that on 115V mains.
sec. then you also half the VA rating. wich will make the transformer even more useless in class A amp
  Reply With Quote
Old 28th September 2012, 10:28 PM   #8
diyAudio Member
 
Join Date: May 2012
Thanks a lot for the replies so far!

So i got some parts info on the mini aleph boards. I have decided to make the aleph j. Im ordering the first pile of parts over the weekend, so I need to know what parts that have changed value. I am sure I can find this info somewhere on this forum, so do you have any pointers?

I have a 14x30x5,5 cm heatsink made for fan cooling. Two heatsinks, half the depth, put together. I know this is not optimal, but if I can skip buying heatsinks and make a smaller aleph fast, I think its worth it.

Do you think its enough? There will be small fans along the length of the sinks, running (hopefully) at sloooow speeds.

Audiosan, you dont happen to live in/around Trondheim?

And at last, the question you all have been waiting for, where can I buy properly matched mosfets and jfets?
  Reply With Quote
Old 28th September 2012, 10:55 PM   #9
diyAudio Member
 
Join Date: Feb 2009
do you know how to replace the irf9610's with J-fets? sj74 or sj109?
matched J-fets sj74 you can ask spencer if he have some
i happend to live IN trondheim bysen.

Last edited by AudioSan; 28th September 2012 at 10:58 PM.
  Reply With Quote
Old 30th September 2012, 08:23 PM   #10
diyAudio Member
 
Join Date: May 2012
I tried to contact spencer, but apparently I cannot pm him.

Is there some kind of "official" bom for the j? I want to begin hoarding parts so I can hear a prototype.

Audiosan, I have never listened to pass labs designs before, please pm me if you could help me with that! I understand if its too much!
  Reply With Quote

Reply


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
New rookie in audio! kyousouhiro Introductions 3 18th April 2009 05:19 PM
Rookie mistake?...Maybe... cjkpkg Tubelab 9 10th October 2008 10:01 PM
help a rookie Xplorer Car Audio 1 22nd June 2004 11:11 AM
Hello from a rookie! lynkage Introductions 1 24th February 2004 08:44 PM
Rookie saying hi! verbalkint Introductions 0 11th February 2002 06:32 AM


New To Site? Need Help?

All times are GMT. The time now is 03:40 PM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2