FirstWatt J2 - 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 23rd September 2009, 08:40 PM   #61
The one and only
 
Nelson Pass's Avatar
 
Join Date: Mar 2001
They don't have any interest that I'm aware of. Perhaps
you want to start buying Sony 2SJ28 and 2SK82's

  Reply With Quote
Old 23rd September 2009, 08:56 PM   #62
Banned
 
Join Date: Nov 2006
Where to buy?
  Reply With Quote
Old 23rd September 2009, 09:09 PM   #63
diyAudio Member
 
R-K Rønningstad's Avatar
 
Join Date: Jan 2006
Location: Oslo
P-channels are probably not necessary in their business plans.

Sony VFETs? Yes, I was absolutely considering doing that. Maybe putting my ZV9 and F5 on hold for a while. Ebay is a terrible place ...

Have you managed to get datasheets of VFETs?
The VFETs are similar to a JFET, except for power (?). But I think I remember something about burned VFET amps in abundance in the 70ties/80ties, or was that maybe the Sony class D with VFETs? (Rumoured to be a not so good implementation.)

I found a few shematics of DIY VFET amplifiers, not All-JFET, so maybe i is funnier to have Google translate them to English...
Anyway, found these:
http://www.est.hi-ho.ne.jp/jack-morita/sub06/sub06.html
http://www.geocities.jp/mutsu562000/hp005.htm
http://homepage2.nifty.com/~mhitaste...eramp_001.html
Even Hiraga have used VFETs http://www.tcaas.btinternet.co.uk/hiraga2.htm

RK
  Reply With Quote
Old 23rd September 2009, 09:24 PM   #64
Vix is offline Vix  Yugoslavia
diyAudio Member
 
Vix's Avatar
 
Join Date: Nov 2003
Location: Somewhere on Planet Earth
Quote:
Originally Posted by Tea-Bag View Post
I speculate it uses a 24v dual rail supply
Or 2x18 v Ac, so...
Attached Images
File Type: jpg j2 supply.JPG (10.7 KB, 1429 views)
  Reply With Quote
Old 23rd September 2009, 09:25 PM   #65
diyAudio Member
 
R-K Rønningstad's Avatar
 
Join Date: Jan 2006
Location: Oslo
Default 2sk77b

BTW it seems the VFET of the Yamaha B-1 exists as the 2SK77B today and is used in an amplifier http://www.digital-do-main.com/product/index.html called starngely enough B-1a.

Thought I had to share this!
  Reply With Quote
Old 24th September 2009, 12:11 AM   #66
diyAudio Member
 
Join Date: Aug 2002
Location: Toronto, Canada
Quote:
Originally Posted by Nelson Pass View Post
Perhaps you want to start buying Sony 2SJ28 and 2SK82's

How many should we get?
__________________
We are fearless amplifier builders. A little heat doesn't scare us at all.
- NP 2002
  Reply With Quote
Old 24th September 2009, 06:51 AM   #67
diyAudio Member
 
R-K Rønningstad's Avatar
 
Join Date: Jan 2006
Location: Oslo
I was thinking of at least 2x n and 2x p per side equals 4 pairs, as each is 10 A and 95 W. But I guess "we" are going first watt class A so it will not be 100 W output power per side. But that was were I would have started, papa might have other and better ideas
  Reply With Quote
Old 24th September 2009, 01:48 PM   #68
Blues is offline Blues  United States
Lightning In A Bottle
diyAudio Member
 
Blues's Avatar
 
Join Date: Sep 2003
Location: The Milky Way
6moons p2...
http://www.6moons.com/audioreviews/f...tt10/j2_2.html
__________________
Life simplified! Leap into the Warpspeed wormhole... http://www.6moons.com/audioreviews/warpspeed/1.html
  Reply With Quote
Old 24th September 2009, 02:01 PM   #69
Telstar is offline Telstar  Italy
diyAudio Member
 
Join Date: Dec 2007
Location: Italy
Quote:
Originally Posted by R-K Rønningstad View Post
I was thinking of at least 2x n and 2x p per side equals 4 pairs, as each is 10 A and 95 W. But I guess "we" are going first watt class A so it will not be 100 W output power per side. But that was were I would have started, papa might have other and better ideas
And if one wanted only 5W?
  Reply With Quote
Old 24th September 2009, 02:03 PM   #70
diyAudio Member
 
R-K Rønningstad's Avatar
 
Join Date: Jan 2006
Location: Oslo

The least is one n and one p per channel, if one does not want to get single ended, me thinks!
Probably more than adequate for 5 W!
  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
An another way to Firstwatt F1? Idefixes Pass Labs 5 1st February 2012 08:40 PM
Subwoofer and Firstwatt F1 tgrauss Subwoofers 10 3rd June 2009 04:29 PM
Fostex and Firstwatt in car? Ipanema Car Audio 2 11th February 2008 05:32 AM
FirstWatt.com Rory Christ Pass Labs 121 31st May 2004 07:02 PM


New To Site? Need Help?

All times are GMT. The time now is 11:23 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