L'Amp: A simple SIT Amp - Page 164 - 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 7th March 2013, 03:28 PM   #1631
diyAudio Member
 
Join Date: Nov 2012
Hi,

Does anyone know what the input impedence of L'amp is? or if it can be varied? I would like to use Lightspeed attenuator in respect of which it is sugested amp has 80kohm or higher impedence.

Thanks Terry
  Reply With Quote
Old 7th March 2013, 03:34 PM   #1632
Zen Mod is offline Zen Mod  Serbia
diyAudio Member
 
Zen Mod's Avatar
 
Join Date: Jan 2003
Location: ancient Batsch , behind Iron Curtain
put Jfet buffer in between

L' is having input imp. well bellow R1 ( 47K) and it's too much varying for Lightspeed
__________________
my Papa is smarter than your Nelson !
clean thread; Cook Book;PSM LS Cook Book;Baby DiyA ;Mighty ZM's Bloggg;Papatreasure;Papa...© by Mighty ZM
  Reply With Quote
Old 7th March 2013, 08:11 PM   #1633
diyAudio Member
 
juanitox's Avatar
 
Join Date: Dec 2006
i use ldr ( Warpspeed) as passive preamp before the SIT with 27K input and it sounds fine..
but for me the magic comes with a tube stage /LDR combo driving the Sit
__________________
French is not a crime.

Last edited by juanitox; 7th March 2013 at 08:15 PM.
  Reply With Quote
Old 17th March 2013, 07:48 PM   #1634
diyAudio Member
 
Join Date: May 2009
Guys, If we would need to design a plate choke specialy made
for 2SK82 what would be the guide lines?
We need usually for 100ohm plate resistance 1H inductance,
so we only need 0.1H here or am I missing something?
The hammond filter choke 193V has 0,3H but is not designed for plate reactor.
Any thoughts?
  Reply With Quote
Old 17th March 2013, 10:06 PM   #1635
Zen Mod is offline Zen Mod  Serbia
diyAudio Member
 
Zen Mod's Avatar
 
Join Date: Jan 2003
Location: ancient Batsch , behind Iron Curtain
even if for toob , it can be useful :

http://vt52.com/diy/tips/platechoke.xls

VT52.com
__________________
my Papa is smarter than your Nelson !
clean thread; Cook Book;PSM LS Cook Book;Baby DiyA ;Mighty ZM's Bloggg;Papatreasure;Papa...© by Mighty ZM
  Reply With Quote
Old 17th March 2013, 10:34 PM   #1636
diyAudio Member
 
Join Date: Jan 2002
Location: Tyrone Ga. U.S.A.
A quick look at an air core inductor calculator shows ~ 7lbs of #16 magnet wire will
let you have over 100mh of inductance with a resistance of about 3.84 ohms. If you play with the dimensions you can use even less wire but as i said that was just a quick look.
  Reply With Quote
Old 18th March 2013, 09:42 AM   #1637
diyAudio Member
 
Join Date: May 2009
Ok...
  Reply With Quote
Old 19th March 2013, 04:35 PM   #1638
diyAudio Member
 
juanitox's Avatar
 
Join Date: Dec 2006
is going parafeed output with the SITAMP will work ? let say we use 130mh
hammond choke what kind of transformer could do the job as parafeed load ?
__________________
French is not a crime.
  Reply With Quote
Old 19th March 2013, 04:50 PM   #1639
diyAudio Member
 
Join Date: May 2009
I am working on a SIT parafeed...It sounds nice, I mean the words...SIT PARAFEED
You wont find a 20-30ohm primary and 10-15W output transformer to use as a parafeed.

I will use higher voltages to be able to use a 50ohm output transformer.
This is an expensive project so far, but will see how it performs. Its an experiment...
  Reply With Quote
Old 19th March 2013, 05:26 PM   #1640
flg is offline flg  United States
diyAudio Member
 
flg's Avatar
 
Join Date: Jul 2005
Location: North East
Quote:
Originally Posted by DIYspaceW View Post
I am working on a SIT parafeed...It sounds nice, I mean the words...SIT PARAFEED
You wont find a 20-30ohm primary and 10-15W output transformer to use as a parafeed.

I will use higher voltages to be able to use a 50ohm output transformer.
This is an expensive project so far, but will see how it performs. Its an experiment...
Have you talked with these guy's???
Autoformers offered by ZeroImpedance- Improve your speaker sound quality with the use of an autoformer.
__________________
"It was the perfect high end audio product: Exotic, inefficient, expensive, unavailable, and toxic." N.P.
  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
L’Amp: A Simple SIT Amp: Part 1 Michael Rothacher diyAudio.com Articles 22 5th October 2013 09:25 AM
SIT Amp Article Out Now Variac Site Announcements 0 2nd December 2011 07:55 AM
Srajan has the 1st SIT amp for Une dégustation vizion Pass Labs 131 14th November 2011 11:41 PM
SIT-Preamp VladimirK Solid State 36 27th August 2011 08:36 PM
New SIT - old problem StevenOH Parts 2 13th June 2008 10:46 AM


New To Site? Need Help?

All times are GMT. The time now is 09:52 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