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 19th September 2012, 11:59 AM   #31
sajti is offline sajti  Hungary
diyAudio Member
 
Join Date: Apr 2003
Location: Vác, Hungary
I did some simulation. Replacing the driver (2SC5171) with 2 paralleled, reduce the open loop distortion from 0.5% to 0.37%, and 3 paralleled reduce it to 0.25%. So it looks good solution!

Sajti
  Reply With Quote
Old 19th September 2012, 12:29 PM   #32
pergo is offline pergo  Italy
diyAudio Member
 
pergo's Avatar
 
Join Date: Dec 2008
what about tube ltp in your new project?
  Reply With Quote
Old 19th September 2012, 12:48 PM   #33
sajti is offline sajti  Hungary
diyAudio Member
 
Join Date: Apr 2003
Location: Vác, Hungary
waiting for the pcb....

Sajti
  Reply With Quote
Old 24th September 2012, 07:59 AM   #34
sajti is offline sajti  Hungary
diyAudio Member
 
Join Date: Apr 2003
Location: Vác, Hungary
The input pcbs are arrived today. I planned another one which will contains the 3 drivers, due I don't want to destroy the existing pcbs.
I will put some pictures about the heatsink assembly, hopefully on next week.

Sajti
  Reply With Quote
Old 24th September 2012, 08:49 AM   #35
Junm is offline Junm  Philippines
diyAudio Member
 
Junm's Avatar
 
Join Date: Dec 2008
Location: Dau
Send a message via Yahoo to Junm
can you post your input stage schematics?
  Reply With Quote
Old 25th September 2012, 02:48 PM   #36
sajti is offline sajti  Hungary
diyAudio Member
 
Join Date: Apr 2003
Location: Vác, Hungary
Input stage attached.

Sajti
Attached Images
File Type: png bridge_driver.png (4.5 KB, 196 views)
  Reply With Quote
Old 4th October 2012, 02:25 PM   #37
sajti is offline sajti  Hungary
diyAudio Member
 
Join Date: Apr 2003
Location: Vác, Hungary
Quote:
Originally Posted by homemodder View Post
I have the service manuals, just did a quick peek some time back. New its not, consult pioneer schematics from that era. In fact it was pioneer which developed that voltage gain stage and at the time it was very much talked about.
I found the A-400 from Pioneer. So it has the output stage looks something like the Marantz. But not exactly same as the Pio contains some opamp as preamplifier on the input. The Marantz circuit looks much more promising, with more carefully designed.

Sajti
  Reply With Quote
Old 4th October 2012, 03:58 PM   #38
Account disabled at member's request
 
Join Date: May 2006
Quote:
Originally Posted by sajti View Post
I found the A-400 from Pioneer. So it has the output stage looks something like the Marantz. But not exactly same as the Pio contains some opamp as preamplifier on the input. The Marantz circuit looks much more promising, with more carefully designed.

Sajti
It boils down to the same design, just because one just has a IC opamp and the other has a discrete one.

When you take it that the pioneer circuit is more than 20 years old I sure would hope that someone copying could at least do one little thing better although I dont see much that is worth the trouble.

Another fact is Pioneeer developed the CFB part back in 1978, long before comlinear patented in around 1985 the use of diamond buffer input stage for CFB opamps. That design already included the so called super linear vas circuit so in all marantz are 30 year behind in savy.
  Reply With Quote
Old 4th October 2012, 06:49 PM   #39
sajti is offline sajti  Hungary
diyAudio Member
 
Join Date: Apr 2003
Location: Vác, Hungary
Quote:
Originally Posted by homemodder View Post
It boils down to the same design, just because one just has a IC opamp and the other has a discrete one.

When you take it that the pioneer circuit is more than 20 years old I sure would hope that someone copying could at least do one little thing better although I dont see much that is worth the trouble.

Another fact is Pioneeer developed the CFB part back in 1978, long before comlinear patented in around 1985 the use of diamond buffer input stage for CFB opamps. That design already included the so called super linear vas circuit so in all marantz are 30 year behind in savy.
I don't really want to fighting with You. So my design is based on Pioneer A-400 power stage.

Sajti
  Reply With Quote
Old 4th October 2012, 06:54 PM   #40
sajti is offline sajti  Hungary
diyAudio Member
 
Join Date: Apr 2003
Location: Vác, Hungary
I have to make some changes, due the original version use 2sc2240/2sa970 in front end. This parts are not manufactured any more, so I have to find some other to replace it.
In the current mirror, and in the input stage I use BC550C/560C (Onsemi), the VAS use 2SC3423/2SA1360 (I feel lucky to order last 300-300pcs from Mouser. In the remaining 4 position (input cascade, and the ccs on the input) I try 2SC2705/2SA1145, KSC1845/KSA992, but unfortunately the original parts give the best sound, so finally I get some of them.

Sajti
  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
Hybrid Amplifier Design Luck Chip Amps 32 3rd March 2009 02:43 AM
The Perfect Hybrid Amplifier Stee Solid State 0 27th July 2008 08:03 PM
Hybrid amplifier.. Please help.. DoomPixie Solid State 96 2nd March 2006 02:54 PM
Hybrid amplifier help... DoomPixie Tubes / Valves 83 20th February 2006 01:28 PM
HYBRID POWER AMPLIFIER - Please Help! gianmaria Solid State 40 20th May 2005 01:46 PM


New To Site? Need Help?

All times are GMT. The time now is 11:32 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