Building an F5 Turbo v2 (in-Progress) - Page 7 - 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 April 2013, 06:44 PM   #61
diyAudio Member
 
buzzforb's Avatar
 
Join Date: Oct 2010
Location: Burlington, NC
good. I just ordered some.
__________________
...Shape the sound , Man!
  Reply With Quote
Old 2nd April 2013, 04:22 PM   #62
diyAudio Member
 
duder1982's Avatar
 
Join Date: Jan 2012
Location: Nebraska
This thread should have some good info.
__________________
If I cant build it or fix it I really dont want it.
  Reply With Quote
Old 5th April 2013, 12:43 AM   #63
6L6 is online now 6L6  United States
diyAudio Member
 
6L6's Avatar
 
Join Date: Oct 2010
Location: Denver, Colorado
Well I finally have gotten a new set of output Fets, and the time to get back into this project.

The short story is that the compensation cap from gate to output (marked as C2 on the output boards, but marked as C3 and C4 on the V3 schematic) need to be used. 1000pF is working well.

Also the gate resistors have been increased to 680ohm. These two changes have seemed to keep it stable. Hooray!

Only one channel up and going right now, the other will be done tomorrow. If everything behaves, I will hopefully have some simple power measurements.

Last edited by Mooly; 5th April 2013 at 06:07 AM. Reason: Corrected info
  Reply With Quote
Old 5th April 2013, 01:43 AM   #64
6L6 is online now 6L6  United States
diyAudio Member
 
6L6's Avatar
 
Join Date: Oct 2010
Location: Denver, Colorado
A few shots of the bench -

Click the image to open in full size.

Click the image to open in full size.

The Front-end board is mounted on the DIY-friendly base because it fits.

Yes, it looks like an explosion at a spaghetti factory - and this is only with one channel... Now I will be the first to mention that I haven't loomed anything together yet, and that will help a bit... but the penality of having the flexibility of the seperate FE board is all the extra wires.

Last edited by 6L6; 5th April 2013 at 01:54 AM.
  Reply With Quote
Old 5th April 2013, 02:39 AM   #65
diyAudio Member
 
bnorrish's Avatar
 
Join Date: Oct 2012
Location: Boston
Quote:
Originally Posted by 6L6 View Post

The short story is that the compensation cap from gate to rail (marked as C2 on the output boards, but only on the V3 schematic) need to be used. 1000pF is working well.
.
Looking great! Those are labelled C3 and C4 on the V3 schematic?

Last edited by bnorrish; 5th April 2013 at 02:43 AM.
  Reply With Quote
Old 5th April 2013, 03:14 AM   #66
6L6 is online now 6L6  United States
diyAudio Member
 
6L6's Avatar
 
Join Date: Oct 2010
Location: Denver, Colorado
Yes. The DIYaudio PCB has it labeled as C2 on the output boards.
  Reply With Quote
Old 5th April 2013, 11:09 AM   #67
Rixsta is offline Rixsta  United Kingdom
diyAudio Member
 
Join Date: Feb 2004
Location: Barrow-In-Furness, Cumbria
Send a message via Skype™ to Rixsta
Quote:
Originally Posted by 6L6 View Post
The short story is that the compensation cap from gate to output (marked as C2 on the output boards, but marked as C3 and C4 on the V3 schematic) need to be used. 1000pF is working well.

Also the gate resistors have been increased to 680ohm. These two changes have seemed to keep it stable. Hooray!
they need to be used in V2 ? or is that only if theres a stability problem, personal id rather be safe than sorry so perhaps i should follow in your footstep(s).
__________________
www.Rixsta.co.uk Free music recorded by me/DIY pics Currently Selling, amps=Zen V4, Zen-lightenment‎, Jean Hiraga 20w, F5, F5T
  Reply With Quote
Old 5th April 2013, 02:28 PM   #68
PKI is offline PKI  United States
diyAudio Member
 
PKI's Avatar
 
Join Date: Aug 2011
So yes, 6L6, you say that your amp was blowing outputs because of these oscillations without this cap? I am interested, cause I am planning on dropping in two extra pairs in my F5Tv2. The question if i too need this cap or not :-)
  Reply With Quote
Old 5th April 2013, 02:57 PM   #69
diyAudio Member
 
buzzforb's Avatar
 
Join Date: Oct 2010
Location: Burlington, NC
If I get a chance, I am gonna hook up the output boards, such that I have 4 output pairs running off single FE board. This will be with standard 47R gate resistors and no cap. fun times.
__________________
...Shape the sound , Man!
  Reply With Quote
Old 5th April 2013, 03:06 PM   #70
PKI is offline PKI  United States
diyAudio Member
 
PKI's Avatar
 
Join Date: Aug 2011
Quote:
Originally Posted by buzzforb View Post
If I get a chance, I am gonna hook up the output boards, such that I have 4 output pairs running off single FE board. This will be with standard 47R gate resistors and no cap. fun times.
I can do it anytime now, I just want to modify mounting technic on my 5U chassis, so I will be able do swap amps in no time. It requires some metal work and sanding, just being lazy :-)
  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
F5 Turbo is posted Nelson Pass Pass Labs 635 6th April 2014 10:51 AM
F5 turbo heatsinks AudioSan Pass Labs 21 31st August 2013 01:47 PM
F5 turbo problems Rob Dingen Pass Labs 17 11th January 2013 08:38 PM
Best way to tune in BIAS F5 V2 Turbo Blink_PT Pass Labs 17 4th January 2013 10:40 AM
F5 Turbo ............. if only !!!!!! a.wayne Pass Labs 23 21st January 2012 02:24 AM


New To Site? Need Help?

All times are GMT. The time now is 02:29 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