DIAMOND DIFFERENTIAL INPUT POWER AMPLIFIER EBay kit - Page 3 - diyAudio
Go Back   Home > Forums > Amplifiers > Solid State

Solid State Talk all about solid state amplification.

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 18th March 2011, 12:33 AM   #21
janusz is online now janusz  Australia
diyAudio Member
 
Join Date: Oct 2004
This is very true, Forr,

This particular amp has two patents (self regulating VAS current and something else if I remember correctly) but the drawback was that this amp (and possibly other Sansui amps as well) operated on the verge of stability. I never had any Sansui equipment and I am not really familiar with their designs. Simply when I saw this kit on EBay I decided to check the net for similar designs before deciding whether to buy it or not and found this Sansui.

cheers,
  Reply With Quote
Old 22nd March 2011, 04:12 PM   #22
diyAudio Member
 
Join Date: Mar 2001
Location: Brazil
I'm looking forward the assembly of this kit. It looks very interesting.

Perhaps a DC servo might allow eliminating the NFB capacitor.
  Reply With Quote
Old 22nd March 2011, 07:02 PM   #23
Dave S is offline Dave S  United Kingdom
diyAudio Member
 
Join Date: Mar 2003
Location: Searchin' for Sweet Singletrack
There is no NFB cap. Matched JFET input and trimming is used instead of a servo.
  Reply With Quote
Old 22nd March 2011, 09:07 PM   #24
diyAudio Member
 
Join Date: Mar 2001
Location: Brazil
Quote:
Originally Posted by Dave S View Post
There is no NFB cap. Matched JFET input and trimming is used instead of a servo.
Yes, there is an NFB cap, from RF2/1K to ground. No value is specified though.

Matching N and P JFets at the input might be a serious problem to accomplish a stable, no-DC output.

In any case, if you have DC protection might be worth trying.
  Reply With Quote
Old 22nd March 2011, 09:17 PM   #25
forr is offline forr  France
diyAudio Member
 
forr's Avatar
 
Join Date: Dec 2004
Location: Next door
Hi Janusz,
I you can afford some Sansui vintage, you may like it. They were well built and very nice to look at. For example, I love my tuner TU555 (excellent sound too), here are some pictures
sansui tu555 - Recherche Google
  Reply With Quote
Old 5th April 2011, 04:32 AM   #26
janusz is online now janusz  Australia
diyAudio Member
 
Join Date: Oct 2004
Attention,
the most recent simulation with Beta24 of the DDInput amp showed that R16=220 with W2 and R28 out of the circuit. Or R16 in parallel with W2 and R28 should be set to 220.

Has anyone already finished building this amp?

cheers,
  Reply With Quote
Old 5th April 2011, 06:17 AM   #27
tvi is offline tvi  Australia
diyAudio Member
 
tvi's Avatar
 
Join Date: Apr 2001
Location: Moonee Ponds, Vic, Australia
The Real Sansui still exists but only in Japan they sold the name in all the other territories.

sansui-jpn
__________________
The small part of ignorance that we arrange and classify we give the name of knowledge.
Ambrose Bierce
  Reply With Quote
Old 16th April 2011, 05:04 PM   #28
diyAudio Member
 
Join Date: Nov 2007
I 'm interested with this amp too, Waiting for your results.
  Reply With Quote
Old 16th April 2011, 06:41 PM   #29
diyAudio Member
 
Join Date: Mar 2001
Location: Brazil
It's now 40 days since this topic started. Has anyone got to any results with the kit?

Does anyone know which commercial amp this project clones? It was established it's not the Sansui. So what is it?
  Reply With Quote
Old 16th April 2011, 07:40 PM   #30
poler is offline poler  United States
diyAudio Member
 
Join Date: Jul 2009
Location: Los Angeles
We all know Sansui is good; however we are more interested in this kit, has anyone tested it? how does it sound?
  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
FS: F5 Amplifier Kit - Boards, Heatinks, Power Caps, Input Caps, RCAs, Binding Posts gripracer Swap Meet 17 6th November 2013 02:28 PM
Sansui Diamond-Differential with current mirror loads and self biased VAS cascodes steph_tsf Solid State 10 15th July 2013 05:29 AM
"An Adjustment-Free Complementary Power Amplifier" by J.Diamond jez Solid State 28 22nd August 2010 11:33 PM
eBay TDA7294 kit + Parts Express Buyout 32V CT 200VA Toroidal Power Transformer? IsleOfMan Chip Amps 7 19th February 2009 08:44 AM


New To Site? Need Help?

All times are GMT. The time now is 01:27 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