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.

BOSOZ low output?
BOSOZ low output?
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 9th October 2003, 08:56 PM   #1
Brownlow is offline Brownlow
diyAudio Member
Join Date: Apr 2001
Location: UK
Default BOSOZ low output?

I've constructed the BOSOZ and the good news is that there is no smoke (I am always happy to get this far!). Anyway, I am using two Panasonic plastic pots at the output, valued at 10K. I chose not to match the transistors and at the moment I am using the amp as unbalanced.

The output seems very low, the volume pots work in that I can turn them all the way to the other end! However, these are the 4 pinned variety that I have not encountered. have I wired the pot wrongly? Also, the voltages on Drain is 31.4v and -4.3v on Source, Gate is grounded. R15 is 221 ohms, as I wanted to see how much gain we're playing with. Have I missed something?
Or is there a thread that someone could direct me to, as always advice is gratefully appreciated.



P.S. I got to start on the Aleph5 next...
  Reply With Quote
Old 9th October 2003, 11:25 PM   #2
Nelson Pass is offline Nelson Pass  United States
The one and only
Nelson Pass's Avatar
Join Date: Mar 2001
BOSOZ low output?
Often a 4 pin pot means that there is a fixed tap on the resistor,
and grounding it gives more of an audio taper than a linear
pot. You are free to ignore it, if that's the case.
  Reply With Quote
Old 31st October 2003, 09:10 AM   #3
Kriss is offline Kriss  Poland
diyAudio Member
Join Date: Oct 2003
Location: Warsaw
Few days ago I hooked up first time my BoSoZ. First impression was probably the same. It works, works fine but output signal was low. It was about twice lower than directly from CD ( CD with variable output so I could compare system with or without aditional preamp betwen CD and amp). I approach gain by decreasing R15 to 100 ohm. The output level now looks OK. Music play on the same volum like directly from CD.
This experience push me to omit input/output pots and adjusting only the gain.


P.S. My next pre will be clone Aleph P 1.7 in P2P configuration.
  Reply With Quote
Old 31st October 2003, 12:26 PM   #4
wuffwaff is offline wuffwaff  Netherlands
diyAudio Member
wuffwaff's Avatar
Join Date: Aug 2001
Location: Ingolstadt Germany
Hello Kriss,

normally gain should be between 10 and 20 dB (x3,16 and 10x) depending on R15 so something must be wrong.

een ooievaar is geen konijn want zijn oren zijn te klein!
  Reply With Quote


BOSOZ low output?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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
BOSOZ Output Waveform Question hifimaker Pass Labs 8 9th April 2007 02:34 AM
bosoz output level skaara Pass Labs 34 2nd October 2005 11:09 PM
Output stage/preamp with gain: X-Bosoz with diff.-pair? Onvinyl Pass Labs 1 19th July 2004 09:29 AM
x-BoSoZ volume on in or output yoke Pass Labs 9 24th June 2004 07:43 AM
What output capacitor value for BOSOZ macka Pass Labs 7 12th May 2004 09:00 PM

New To Site? Need Help?

All times are GMT. The time now is 07:23 PM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 16.67%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright ©1999-2017 diyAudio