How do my output boards look? - 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 14th July 2004, 03:54 PM   #1
diyAudio Member
 
punchpeanut's Avatar
 
Join Date: Jul 2003
Location: twin cities
Default How do my output boards look?

Here is my first try at output boards for the Aleph X. The same board sould work for and Aleph as well. Each has 4 fets and I mirrored connections on both sides of the board with the idea that boards could be daisy-chained for higher output.

4 boards 16 fets
8 boards 32 fets
12 boards 48 fets
16 boards 64 fets

If I did it wrong please critique, I've got some pretty thick skin.

peanut
Attached Images
File Type: jpg toutput.jpg (48.4 KB, 1191 views)
  Reply With Quote
Old 14th July 2004, 04:08 PM   #2
Taco is offline Taco  Netherlands
diyAudio Member
 
Join Date: Nov 2002
Location: Place in the Netherlands
It looks oke to me, but I should put more space between the fets to get better cooling.
  Reply With Quote
Old 14th July 2004, 04:13 PM   #3
diyAudio Member
 
punchpeanut's Avatar
 
Join Date: Jul 2003
Location: twin cities
Maybe I should drop it to a 3 fet per board design. Since I'm using the freeware eagle I can only go 4 inches wide. That way 12 boards would yeild 36 fets which is pretty close to the Pass XA200 that has 32.
  Reply With Quote
Old 14th July 2004, 04:22 PM   #4
diyAudio Member
 
punchpeanut's Avatar
 
Join Date: Jul 2003
Location: twin cities
Here's the 3 fet version.
Attached Images
File Type: jpg toutput3.jpg (38.0 KB, 768 views)
__________________
The Yodelin' Peanut
  Reply With Quote
Old 14th July 2004, 04:30 PM   #5
diyAudio Member
 
hifimaker's Avatar
 
Join Date: Oct 2003
Location: San Jose
Here's some existing art from W. Sankey's gallery page on passdiy.com.

Outboard art is at the bottom of the .pdf page:
http://www.passdiy.com/pdf/a2-p1-pcbs.pdf

Picture of finished boards:
http://www.passdiy.com/images/aleph%...y/a2-p1-f8.jpg

This might be helpful if you need larger boards.

-David
  Reply With Quote
Old 14th July 2004, 04:35 PM   #6
tiroth is offline tiroth  United States
diyAudio Member
 
Join Date: Dec 2001
Location: Pittsburgh, PA, USA
Thick heatsink backplates really spread the heat. If you want to go to 3 or are really pushing the limits in terms of dissipation versus delta T then go for it, otherwise 4 should be fine.

It also depends a bit on the geometry of your heatsinks; if they are crazy long/wide then there is more incentive to even out the spacing.
  Reply With Quote
Old 14th July 2004, 05:27 PM   #7
diyAudio Member
 
punchpeanut's Avatar
 
Join Date: Jul 2003
Location: twin cities
Thanks guys, The pdf link dw8083 is great! I wanted to make an aleph 2 and that is compete. Since the software I'm using only lets me have a max width of 4 inches I can't add more fets. Otherwise I'd also make a 6 and an 8 fet version too.

Thanks also to tiroth, I didn't even think about that. I will be using sinks from Conrad, they should be fine since I am thinking of doing a 32 fet amp with each fet running at 5 - 8 watts. The 4 fet board should be fine.
__________________
The Yodelin' Peanut
  Reply With Quote
Old 14th July 2004, 05:31 PM   #8
OliverD is offline OliverD  Germany
diyAudio Member
 
OliverD's Avatar
 
Join Date: Nov 2002
Location: Germany
The gate resistors should be as close to the FETs as possible - I did it almost exactly like you in my own design, but I was told every mm matters
  Reply With Quote
Old 14th July 2004, 05:40 PM   #9
K-amps is offline K-amps  United States
diyAudio Member
 
K-amps's Avatar
 
Join Date: Nov 2003
Location: Indiana
I'd go with 4 myself assuming that good heatsinks will be used with the Aleph's. Its a trade-off between number of boards vs. ease of installation vs. cost of boards vs. thermal spacing etc.

I like your 4 device version and especially the ability to daisy chain them!!
  Reply With Quote
Old 14th July 2004, 05:49 PM   #10
diyAudio Member
 
punchpeanut's Avatar
 
Join Date: Jul 2003
Location: twin cities
Here is a 4 fet version with the gate resistors almost on top of the fet leg, thanks for the advice! I will also post a bare image of just the traces. I'm kind of proud of myself for thinking of the daisy-chain thing .
Attached Images
File Type: jpg toutput.jpg (46.3 KB, 700 views)
__________________
The Yodelin' Peanut
  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
L/R Boards and Matched IRFP240 Boards for Aleph/ A-X lgreen Swap Meet 7 25th August 2009 04:56 AM
FS: Conrad Heatsinks;.... 'PASS' B1 boards w/JFETS;...... F4 AMP & PSU boards cowboy99 Swap Meet 5 25th August 2009 02:39 AM
Pass Aleph 1.7 boards, Zhaolu 2.5A, P700 VRDS, UGS PS boards, dac chips analog_sa Swap Meet 4 14th March 2009 05:29 PM
WTB: Aleph X Output Boards Reima Swap Meet 10 17th March 2008 12:58 PM
Simple DCX2496 analog output boards novec Group Buys 1 18th September 2007 05:32 PM


New To Site? Need Help?

All times are GMT. The time now is 01:45 AM.


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