Zen Enlightenment. - Page 2 - diyAudio
Go Back   Home > Forums > Amplifiers > Pass Labs
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

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
Thread Tools Search this Thread
Old 17th January 2001, 12:47 AM   #11
FYC is offline FYC  Hong Kong
diyAudio Member
Join Date: Jan 2001
Location: Hong Kong
There must be something wrong if you need to use a 100k VR to get to 18V at the drain. With what you describe, certainly you need to recheck your complete wiring and your MOSFET. MOSFET are easily killed by statics, or it run into oscillation due to connection problems.

Don't give up, my Zen amp work perfectly immediately after hook up, and was so far so good. It is not a terribly difficult project.
  Reply With Quote
Old 17th January 2001, 04:54 PM   #12
diyAudio Member
Join Date: Oct 2000
Location: Austin, Texas, USA
Please, stop saying it's not a difficult project!

This is my first analog circuit!
To prove my predisposition to digital, I just remembered yesterday that the G is for Grid not Gate. Sad.

Thanks for the help though. It's appreciated. I wouldn't have gotten this far without you guys. Especially Vince. Thanks man.

I think I will get that circuit board. I'm going to keep the power supply part separate though. My father made me an aluminum case that has a separate section for the power supply. And, I'll remember to check the diagram for the connection of the small transistor. I'm going to start over with new FETs. So, I'll be starting with a clean slate.

  Reply With Quote
Old 18th January 2001, 12:38 AM   #13
FYC is offline FYC  Hong Kong
diyAudio Member
Join Date: Jan 2001
Location: Hong Kong
My appology, G in MOSFET is Gate, Grid is for tube. My mistake.

  Reply With Quote
Old 19th February 2001, 02:14 PM   #14
peted is offline peted  United Kingdom
diyAudio Member
peted's Avatar
Join Date: Feb 2001
Location: U.K. - S. Oxon
Hi Pixie et al - hope you got it going! Others said it's not difficult - I agree - your probs have got to be due to zapped mosfets, bad wiring, etc. Give it another go - hand check all the bits like vdi_nenna said that could cook before inserting, wire mosfet leads & remove only when wired the rest (is this overkill?). Resistors - cute new(?) coding scheme - are you getting them right - DON'T always rely on the supplier doing so either).

I'm building beefed up Zen Revisited - 4amp bias, 50v psu, twin paralleled channels working into 4ohm spkrs. 2 of 4 completed channels worked first time - but you need to set bias point (as advised by NP) for symetrical clipping ('scope) - it's NOT 1/2 supply volts - rather more like 60% - that cooks the lower mosfet more too - beware the h/sinks.

I'll report results (& any more hints) in due course... Not put these 2 together yet... Most difficult (in a domestic environment) is the heatsink with these things. 80% of my effort - high bias, high volts - VERY big h/s ( Great results (

Pre-amp will be BOZ - NP says it'll be fine into the 500ohm i/p (2 parallel amps). BOZ as published (5K o/p pot) will have a very skewed volume curve into Zen Revisited with it's much lower i/p impedance too. I've worked out stepped attn. resistor vals to hopefully match the two - we'll see..

Cheers to all

  Reply With Quote


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
Driver selection - Enlightenment needed please revans Multi-Way 14 10th March 2009 12:40 AM
Enlightenment on impedance matching, please labougie Multi-Way 3 21st December 2008 09:47 AM
Help with DPA Enlightenment Transport Farty Unwash Everything Else 2 25th March 2004 03:41 PM
Source Follower Enlightenment SteveS Pass Labs 3 20th June 2002 09:58 PM
Zen Enlightenment Attained! pixie Pass Labs 7 31st January 2001 06:53 PM

New To Site? Need Help?

All times are GMT. The time now is 02:37 AM.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright ©1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2