Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Pass Labs This forum is dedicated to Pass Labs discussion.

L'Amp: A simple SIT Amp
L'Amp: A simple SIT Amp
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 17th October 2019, 03:30 PM   #3101
Rodeodave is offline Rodeodave  Austria
hates ground loops
diyAudio Member
 
Rodeodave's Avatar
 
Join Date: Dec 2004
Location: in the alps
L'Amp: A simple SIT Amp
The two wire links that join the rails were what I had on hand yesterday evening. I intend to use a copper bar or plate to replace them.

I'll also be using shielded RG316U cables for the input wiring.

I haven't done too many measurements yet, just a quick tuning of the sweetspot (~52VDC supply after reg, 2.3 A Id, 0.13% THD). So far so good.

I'll be pulling some numbers from the circuit over the weekend.

I've been listening to the amp though the HD800 for an hour this morning. In one word, euphonic.
__________________
Gravity - Making the G since 13.7 billion B.C.
  Reply With Quote
Old 18th October 2019, 10:49 AM   #3102
maxlorenz is offline maxlorenz  Chile
diyAudio Member
 
maxlorenz's Avatar
 
Join Date: Oct 2003
Location: osorno , Chile
Quote:
Originally Posted by Zen Mod View Post
in this case he's safe , simply because each (of these two) cap is on single rail , each is having own separate ground feed and there is no current flow between them

in short - Lucky Bztrd

OK. I confess I didn't dare to check thoroughly the drawing

At the risk of being repetitive, I recommend to add later a good input section. That helps a lot with complex music, like big symphonic works.

As time allows, I promised myself to cascode (or bootstrap) the output, like I did with the ZCA AKA Zero Component Amp.

Best wishes,
M.
  Reply With Quote
Old 18th October 2019, 11:02 AM   #3103
Zen Mod is offline Zen Mod  Serbia
Official Court Jester
diyAudio Member
 
Zen Mod's Avatar
 
Join Date: Jan 2003
Location: ancient Batsch , behind Iron Curtain
L'Amp: A simple SIT Amp
put link of your ootoobe channel on your blog
__________________
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 30th October 2019, 08:11 PM   #3104
Rodeodave is offline Rodeodave  Austria
hates ground loops
diyAudio Member
 
Rodeodave's Avatar
 
Join Date: Dec 2004
Location: in the alps
L'Amp: A simple SIT Amp
Good news, everyone!

I found the aluminum plate from the cutout for the switched IEC power inlet and am now using it to connect all the circuit grounds. And it works, beautifully! Not the slightest hum with a source and headphones connected.

I took some measurements with an input of 1V at 1kHz. Output (over 10R load) was 2.466V or 7.83dBV. Distortion was 0.16% (drops down to like 0.04% at headphone listening levels) and S/N ratio was just shy of 91dB. Not too bad I'd say.

Attached you'll also find a snapshot of the residual distortion signal (purple trace) and a simple FFT. H3 ia slightly dominant over H2, and H4 is already way down. I'll be playing with the sweet spot and the resulting spectrum over the coming weekend, should be fun.
Attached Images
File Type: jpg 20191030_202357.jpg (991.2 KB, 576 views)
File Type: jpg 1572465963002882238069.jpg (997.5 KB, 559 views)
File Type: jpg 20191030_202641.jpg (624.0 KB, 550 views)
File Type: jpg 20191030_202959.jpg (994.6 KB, 531 views)
File Type: jpg 20191030_203853.jpg (940.8 KB, 519 views)
__________________
Gravity - Making the G since 13.7 billion B.C.
  Reply With Quote
Old 30th October 2019, 08:32 PM   #3105
Zen Mod is offline Zen Mod  Serbia
Official Court Jester
diyAudio Member
 
Zen Mod's Avatar
 
Join Date: Jan 2003
Location: ancient Batsch , behind Iron Curtain
L'Amp: A simple SIT Amp
yup , sweetspotting , to invoke 2nd above 3rd , as is logical for part used
__________________
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 9th April 2020, 03:47 PM   #3106
juanitox is offline juanitox  France
diyAudio Member
 
juanitox's Avatar
 
Join Date: Dec 2006
Default Oops i did it again

having time to spend as many here , i have rebuilt for the X times my Sitamp
exit hte big Tokin THF51s with CCS and Nemesis TANGO transformer version

and return to the simple Sony Vfet with 12,7 R load . 61V B+ ( 43V 1.45A for the VFET)
fixed bias with Cinemag input transformer. works perfectly as usual
but i wonder for those who have distorsion meters what will be the sweet spot
with my " higher" voltage than usual for resistor load Sony 2SK82 ?

Click the image to open in full size.
__________________
French is not a crime.
  Reply With Quote
Old 6th May 2020, 11:31 PM   #3107
Ylab is offline Ylab  Canada
diyAudio Member
 
Join Date: May 2013
Location: Quebec
Hi there,

I’m planning a built of the L’amp with the 2sk182es + hammond 193v. I’ve seen a video of mr Rothacher talking about the development of Soundhappy’s L’amp with the 2sk182es but have not found any info fallowing that. Is there anybody that have built the L’amp with the 2sk182es that could give me some info about the psu voltage for that configuration?

Merci !

Hubert
  Reply With Quote
Old 7th May 2020, 12:20 AM   #3108
Soundhappy is offline Soundhappy  France
diyAudio Member
 
Soundhappy's Avatar
 
Join Date: Oct 2012
Location: Montpellier near Mediterranean Sea France
It's was simplified version schematic with 2SK79 and 2SJ28 vfet's by Mr. MR
What To Do With Those 2SJ28's
link 2: What To Do With Those 2SJ28's
2SK182ES L'Amp version find in this video Lab Hangout #4 start at ~16min10s.
Oh yeah I am Mr. MR fan boy and ask more about less top secret stuff Joke
__________________
class A amplifiers with full range speakers
sings like angels in heaven
  Reply With Quote
Old 7th May 2020, 01:39 AM   #3109
Soundhappy is offline Soundhappy  France
diyAudio Member
 
Soundhappy's Avatar
 
Join Date: Oct 2012
Location: Montpellier near Mediterranean Sea France
Quote:
Originally Posted by Ylab View Post
Hi there,

I’m planning a built of the L’amp with the 2sk182es + hammond 193v..
I am not aware , probably no one has build L'Amp 2SK182ES with inductor load
Meantime this is instructive article :

http://blog.audiomaker.tech/pdf/lamp%20part%20deux.pdf

another about gate leakage and bias:

Fun With PASS-SIT-1 | AudioMaker
__________________
class A amplifiers with full range speakers
sings like angels in heaven
  Reply With Quote
Old 7th May 2020, 01:50 AM   #3110
Ylab is offline Ylab  Canada
diyAudio Member
 
Join Date: May 2013
Location: Quebec
Quote:
Originally Posted by Soundhappy View Post
2SK182ES L'Amp version find in this video Lab Hangout #4 start at ~16min10s.
Yes that’s the video I was talking about, at 14min he talks about Soundhappy 2sk182 amp

Thank you Soundhappy for your answers and all the links it’s really appreciated!

Hubert
  Reply With Quote

Reply


L'Amp: A simple SIT AmpHide 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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Srajan has the 1st SIT amp for Une dégustation vizion Pass Labs 133 19th October 2019 08:31 AM
L’Amp: A Simple SIT Amp: Part 1 Michael Rothacher diyAudio.com Articles 23 1st September 2014 01:02 AM
SIT Amp Article Out Now Variac Site Announcements 0 2nd December 2011 07:55 AM
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 11:43 PM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2020 DragonByte Technologies Ltd.
Copyright ©1999-2020 diyAudio
Wiki