Suggestions for SemiSouth R100s - Page 2 - 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 20th April 2011, 09:41 PM   #11
diyAudio Member
 
buzzforb's Avatar
 
Join Date: Oct 2010
Location: Burlington, NC
Don't have that kind of hush money! Maybe a nice new pocketbook would do the trick.
  Reply With Quote
Old 20th April 2011, 11:43 PM   #12
GregH2 is offline GregH2  Australia
diyAudio Member
 
GregH2's Avatar
 
Join Date: Oct 2009
Out of curiosity, where are you getting these parts from (if you're able to share)? I'd love to get my hands on some.
  Reply With Quote
Old 20th April 2011, 11:44 PM   #13
diyAudio Member
 
buzzforb's Avatar
 
Join Date: Oct 2010
Location: Burlington, NC
Zhoufang in swap meet.
  Reply With Quote
Old 21st April 2011, 12:38 AM   #14
GregH2 is offline GregH2  Australia
diyAudio Member
 
GregH2's Avatar
 
Join Date: Oct 2009
Quote:
Originally Posted by buzzforb View Post
Zhoufang in swap meet.
Ah, what a shame. Is anyone aware of any online retailers that can sell relatively small quantities?
  Reply With Quote
Old 21st April 2011, 12:42 AM   #15
diyAudio Member
 
buzzforb's Avatar
 
Join Date: Oct 2010
Location: Burlington, NC
Quote:
Originally Posted by swordfishy View Post
Ah, what a shame. Is anyone aware of any online retailers that can sell relatively small quantities?
I am sure he would love to sell you as few or as many as you are willing to buy. They come matched too.
  Reply With Quote
Old 21st April 2011, 01:57 AM   #16
diyAudio Member
 
buzzforb's Avatar
 
Join Date: Oct 2010
Location: Burlington, NC
Quote:
Originally Posted by Nelson Pass View Post
When I get lower distortion out of a part I tend to use it as
an excuse for less feedback, so the net result is often not
less measured distortion.

I like the sound of the Jfets - it's more relaxed and organic
in quality, and of course this reflects my taste. If I listened
to punk or metal, or if I am watching TV or driving the car,
then these things wouldn't be important.

This makes me want to read the negative feedback article again. Seems like sonic purity is your quest. One last bothersome question if I may. How would you describe the sound of a fet circlotron. Thinking for a while of using SS fets in this unusual schem. Many have built one, but sound is not often spoken of. Perhaps fellow builders have grown wise to the trap of describing ones personal musical experience.
  Reply With Quote
Old 21st April 2011, 03:52 AM   #17
diyAudio Member
 
Join Date: Apr 2008
link to negative feedback article?
  Reply With Quote
Old 21st April 2011, 03:59 AM   #18
diyAudio Member
 
Join Date: Aug 2008
http://passdiy.com/pdf/distortion_feedback.pdf
  Reply With Quote
Old 21st April 2011, 01:29 PM   #19
Snokker is offline Snokker  Netherlands
diyAudio Member
 
Snokker's Avatar
 
Join Date: Jan 2004
Location: Netherlands
Default Negative feedback with SS R100 in Circlotron

I use the R100's in a circlotron (2x +28V supplies) with a bit less feedback, and I must say these SS are very stable. I think the need of feedback depends on the speakers you use.
Please do mind that the gain changes with the amount of feedback:
>nfb = <gain

It's important to keep the volume at the same level in comparative listening tests....
My circlotron sounds a bit more laid back (or natural?) than my F5. But bass control is really, really good on my 4 Ohms 94dB 'd appolito system.
And 50W@4Ohm is more than enough
So I can really recommend using the R100's in a circlotron setup, but don't cut corners in the power supplies!
Have fun!

Last edited by Snokker; 21st April 2011 at 01:38 PM.
  Reply With Quote
Old 21st April 2011, 01:40 PM   #20
Tea-Bag is offline Tea-Bag  United States
not politcally affiliated
diyAudio Member
 
Tea-Bag's Avatar
 
Join Date: Feb 2006
Location: Kennebunk
Blog Entries: 7
Quote:
Originally Posted by Snokker View Post
I use the R100's in a circlotron (2x +28V supplies) with a bit less feedback, and I must say these SS are very stable. I think the need of feedback depends on the speakers you use.
Please do mind that the gain changes with the amount of feedback:
>nfb = <gain

It's important to keep the volume at the same level in comparative listening tests....
My circlotron sounds a bit more laid back (or natural?) than my F5. Butt bass control is really, really good on my 4 Ohms 94dB 'd appolito system.
And 50W@4Ohm is more than enough
So I can really recommend using the R100's in a circlotron setup, but don't cut corners in the power supply!
Have fun!
Did you use MRothatcher's design?

I've listened to a few variations of SemiSouths

1. BA-1 with 1 output
2. Mini-A with SSR100 output
3. BabelfishJ2
4. F2J

The bottom three sounded the best to me, with 2,4 having a similiar flavor. The Mini-A sounds a bit more 'warm' than the others.
The F2J with no feedback really is really really nice, and the BabelFish J2, can change it's sonic signature playing around with source and gate resistors.

I tried a variation on what the J2 appears to look like, but removed the current limiting and set a pair of R100's on fire!

All of them sound can sound 'cleaner' than the IRFP240 counterparts. As I've stated elsewhere, Whisky for MOSFET, Vodka for R100 JFET.

I think with a circlotron that maybe the R085's could be used?
  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
Semisouth Aleph J? buzzforb Pass Labs 59 28th February 2014 06:53 AM
SemiSouth Donuts Zen Mod Pass Labs 183 20th July 2013 12:13 PM
Semisouth JFET GB Magura Group Buys 418 14th December 2010 07:49 AM
Semisouth JFET's: What are they good for? Magura Pass Labs 160 10th May 2010 04:11 PM
semisouth for bosoz?!? ijomojo Pass Labs 9 9th February 2010 08:58 PM


New To Site? Need Help?

All times are GMT. The time now is 08:50 AM.


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