Pictures of your diy Pass amplifier - Page 100 - 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 1st January 2012, 05:58 PM   #991
diyAudio Member
 
mhouston's Avatar
 
Join Date: Jan 2006
Location: Victoria, Australia
Quote:
Originally Posted by merlin2069er View Post
Here's a little jfet boz I quickly slapped up together. I think I should use a shielded cable on the input. I'm going to use an external battery pack (2x 9v).
I think if you can avoid shielded cable do. I very rarely use it. You should not need it as all signal voltages entering the preamp should be better than a volt or two. Earth the case if you get hum. I power some of my BoZi on batteries but I have a very simple external supply made from a 24VAC wall wart. I rectify and lightly filter the power external to my BoZ (in this case my BoZSE). It does require that you have at least 20,000uf of storage cap on your BoZ cct.brd. as I do (BoZSE - 30,000uf). This is part Hiraga and Pass design to have this much storage directly on board.

Using the external DC PS means only DC (though only lightly filtered) enters the BoZ. In the PS I use a 10uf poly after the rec. bridge then a 680ohm resistor (can vary) then 1000uf low ESR cap.
Attached Images
File Type: jpg External PS.jpg (155.3 KB, 1491 views)
File Type: jpg External PS_I.jpg (148.5 KB, 1440 views)
File Type: jpg External PS_II.jpg (159.8 KB, 1387 views)
File Type: jpg BoZSEs.jpg (453.5 KB, 1325 views)
  Reply With Quote
Old 1st January 2012, 06:32 PM   #992
diyAudio Member
 
merlin2069er's Avatar
 
Join Date: Sep 2008
Location: Toronto
Blog Entries: 1
Send a message via MSN to merlin2069er
Thanks for the suggestions.

How do I go about earth grounding the case? I use a 24v dc walwart (currently) and there is some hum.
  Reply With Quote
Old 1st January 2012, 09:34 PM   #993
diyAudio Member
 
mhouston's Avatar
 
Join Date: Jan 2006
Location: Victoria, Australia
Quote:
Originally Posted by merlin2069er View Post
Thanks for the suggestions.

How do I go about earth grounding the case? I use a 24v dc walwart (currently) and there is some hum.
Remember there is DC going into the case. Take the negative of the PS and attach to the case. Usually the the negative (non-hot) wire of RCAs attaches to the case too unless you used isolating RCAs. I often use isolating RCAs because they look better then ground the negative of the RCA to the case.

Some like to use a 100ohm resistor to ground the negative of the PS to the case and some also by-pass this with a small cap.
  Reply With Quote
Old 2nd January 2012, 03:27 PM   #994
diyAudio Member
 
Join Date: Oct 2009
Hi Guys,

You have plenty of very nice constructions in this thread. What about some more humble approach;-)
The monoblocks are Zens. The PCB to the left is BOZ.

Greg
Attached Images
File Type: jpg wzm1.jpg (60.3 KB, 1203 views)
File Type: jpg wzm2.jpg (61.1 KB, 757 views)
  Reply With Quote
Old 2nd January 2012, 04:38 PM   #995
norb is offline norb  Germany
diyAudio Member
 
Join Date: Mar 2007
Location: Germany
my sweeeeet little A75
Attached Images
File Type: jpg A75-EnclosureFrontsm.jpg (188.5 KB, 631 views)
File Type: jpg A75-EnclosureTopsm.jpg (190.1 KB, 680 views)
File Type: jpg A75-Insidesm.jpg (272.9 KB, 844 views)
File Type: jpg A75-OneChannelsm.jpg (238.7 KB, 816 views)
  Reply With Quote
Old 2nd January 2012, 04:50 PM   #996
diyAudio Member
 
jacco vermeulen's Avatar
 
Join Date: Oct 2004
Location: At the sea front, Rotterdam or Curaçao
Send a message via Yahoo to jacco vermeulen
Norbert, great fun to see the final outcome of your A75 endeavour.
(even your rectifier diodes are uncommon)
__________________
The buck stops Here
  Reply With Quote
Old 2nd January 2012, 09:11 PM   #997
diyAudio Member
 
mhouston's Avatar
 
Join Date: Jan 2006
Location: Victoria, Australia
merlin2069er: what are your output caps in your BoZ? I don't use input caps only output caps.
  Reply With Quote
Old 2nd January 2012, 09:14 PM   #998
Preamp is offline Preamp  Germany
ulti.preamp.org
diyAudio Member
 
Preamp's Avatar
 
Join Date: Jul 2008
Location: North Sea, 54.7N 8.5E
Norbert, nice heatsinks! Were they salvaged from an old thyristor bank?
  Reply With Quote
Old 2nd January 2012, 10:46 PM   #999
diyAudio Member
 
merlin2069er's Avatar
 
Join Date: Sep 2008
Location: Toronto
Blog Entries: 1
Send a message via MSN to merlin2069er
Here's a close up of the jfet boz ... I bought these caps on ebay (paper in oil) from vintage audio lab.

Click the image to open in full size.

Last edited by merlin2069er; 2nd January 2012 at 10:49 PM.
  Reply With Quote
Old 3rd January 2012, 12:10 AM   #1000
diyAudio Member
 
mhouston's Avatar
 
Join Date: Jan 2006
Location: Victoria, Australia
Quote:
Originally Posted by merlin2069er View Post
Here's a close up of the jfet boz ... I bought these caps on ebay (paper in oil) from vintage audio lab.
Nice caps. Your build is almost a BoZoaC.
  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
DIY Low Pass and Mid/High Pass (Bass Blocking) Filters runslikealpaca Everything Else 1 19th June 2009 10:59 PM
Naked pictures of Pass Pete Fleming Pass Labs 30 9th December 2006 06:39 AM
My new hifi amplifier (pictures) Wejp Chip Amps 23 15th October 2004 12:16 AM
Pass Diy High Low Pass Please macka Pass Labs 127 2nd March 2004 11:00 PM
DIY Pass labs 100watt amplifier. microwalsh8504 Pass Labs 12 6th February 2004 07:27 PM


New To Site? Need Help?

All times are GMT. The time now is 02:40 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