Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Pass Labs This forum is dedicated to Pass Labs discussion.

Aleph J-X Amp Project
Aleph J-X Amp Project
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 17th June 2009, 10:18 AM   #101
tryonziess is offline tryonziess  United States
diyAudio Member
Join Date: Apr 2007
Do you foresee any major problems with the addition of an X circuit to the J. Will a lot of tweeking of resistors and such be an issue.
I have been looking forward to building an X type amp but never got to the GB for the boards in time. Thanks for your efforts Tad
  Reply With Quote
Old 17th June 2009, 02:19 PM   #102
Peter Daniel is offline Peter Daniel  Canada
diyAudio Member
Peter Daniel's Avatar
Join Date: Jul 2002
Location: Toronto, Canada
Aleph J-X Amp Project Send a message via AIM to Peter Daniel
I don't see any problems with that, the main boards will be exactly AJ circuit, and I simply add pads to mount daughter board (3 pins on each side for the gates, out and ground). The front end circuitry will be inside marked area and for X version not installed. The balanced input goes directly to the daughter board (the X amp will also work with unbalanced signal), the daughter board is powered with separate wires from main supply, output is taken from between output boards. That could be the best X amp ever
“Do something really well. See how much time it takes. It might be a product, a work of art, who knows? Then give it away cheaply, just because you feel that it should not cost so much, even if it took a lot of time and expensive materials to make it.” - JC
  Reply With Quote
Old 17th June 2009, 04:46 PM   #103
tryonziess is offline tryonziess  United States
diyAudio Member
Join Date: Apr 2007
Sounds like a winner to me. Nelson was always very fond of this particular version of the Aleph series. The best yet would be a nice thing to achieve.
I will stay tuned to see how things progress.
Need to find some nice healthy heatsinks.

Thanks Tad
  Reply With Quote
Old 17th June 2009, 05:03 PM   #104
audiotony is offline audiotony  United States
diyAudio Member
Join Date: Jan 2007
Location: Florida
Also interested in a stereo pair.

  Reply With Quote
Old 17th June 2009, 05:21 PM   #105
SRMcGee is offline SRMcGee  United States
diyAudio Member
SRMcGee's Avatar
Join Date: May 2004
Location: Wynnewood, PA
Aleph J-X Amp Project

Are there any practical limits on the size of an Aleph JX amp? I currently have Aleph 1.2 monoblocks and would love to try to build something of similar size and power. Assuming it's plausible, count me in as well.

Many thanks,
  Reply With Quote
Old 17th June 2009, 09:42 PM   #106
tryonziess is offline tryonziess  United States
diyAudio Member
Join Date: Apr 2007
What would the projected output be for the JX with 25-30 volt rails? It is now a balanced amp with + and - at the speaker terminals.

  Reply With Quote
Old 17th June 2009, 11:53 PM   #107
MEGA_amp is offline MEGA_amp
diyAudio Member
MEGA_amp's Avatar
Join Date: Oct 2003
I think your limited to about +/-24V, due to the voltage limitation of the JFets. An Aleph JX, shouldn't be much different in output wattage than a 12 output Fet AlephX, which for 22-24 volt rails gives around 100w into 8R, but I could be wrong.

  Reply With Quote
Old 18th June 2009, 12:19 AM   #108
wongstein is offline wongstein  Canada
diyAudio Member
Join Date: Mar 2004
Location: Toronto
Default Me two

Hi, I'd like two stereo boards as well, please. Thanks for doing this!

  Reply With Quote
Old 18th June 2009, 03:40 AM   #109
Luke is offline Luke  New Zealand
diyAudio Member
Join Date: Sep 2001
Send a message via AIM to Luke
Hi Peter, Perhaps its possible to allocate holes for 2 or 3 pairs of parallel input jfets?
  Reply With Quote
Old 18th June 2009, 06:52 AM   #110
gaborbela is offline gaborbela  Canada
diyAudio Member
Join Date: Sep 2005
My Aleph X it uses 8PC power mosfet one side (one channel)at 7A bias over 100W/ channel .Of course I do not push it to 100Watt never to drive my speakers .
So I think 12PC /channel is more than enough !
The IRFP type mosfet tend to sound much better in high bias than normal bias .I know that it will decrease the life time the mosfets but the sound of the amp is more important to me ! We can replace the mosfets every 5 years or so , depend how often U use your amp and the size of the heat sink is must be not under rated .
I use the Cristijan type of PC board and I can say I'm more than happy with the result .
Also I prefer tho connect the output mosfets direct to the PC board .
I tested the wiring method (just I added 2" wire and the sound be came awful compare the direct connected power mosfet to the PC board) I did tested , I just mode one channel at the time .Only I did it to spread the heat a bit better .But Peter wrote the X PC board would be 8" long .That is more than enough with a good heat sink .
I only interested high power version , is important to the IRFP mosfets the 24V power supp min. must .The master wrote that himself .
Mini Aleph X or something like that I think a waste of effort com pair a well biased not X version Aleph (that is my humble opinion ) I'd rather remain at the original J version than use low voltage power supp for the X-ed version !
These just my opinion .
But if the power supply voltage can be flexible a bit that would be great .So we could use transformer what we think is the best best solution for the good sound .
I read many people wrote they do not like the Cristijan type set up for the Aleph X .But please firs take a listening test and after have your opinion .I write these humble , I do not want to argue with no one .
  Reply With Quote


Aleph J-X Amp ProjectHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
aleph 30 project traw Pass Labs 24 15th June 2012 05:47 AM
X Aleph Project Down Under macka Pass Labs 111 30th June 2008 01:55 PM
Aleph 2 project Thago Pass Labs 2 21st April 2007 07:44 AM
My aleph 2 project Jean Pass Labs 13 21st January 2004 07:14 AM
Aleph 2 (& others) as a project GRollins Pass Labs 41 11th February 2002 12:05 AM

New To Site? Need Help?

All times are GMT. The time now is 04:33 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 15.79%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright ©1999-2017 diyAudio