Ultimatest Passive Tone Control Network based on James-Baxandall's topology wanted - Page 2 - 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 8th September 2011, 09:15 AM   #11
diyAudio Member
 
tiefbassuebertr's Avatar
 
Join Date: Jul 2005
Location: D-55629 Schwarzerden
Thanks for all hints.
Quote:
Originally Posted by banat View Post
Tiefbass check the Luxman integrated Amps for `` Duo Beta `` tone control circuit !
Best Regards
That was an excellent advice. In the attachement the schematic of the Baxandall part from Luxman's L-550 Class-A integrtated amp. Schematic you will get about "hifi engine" for free after login. If I transform the line cascode stages to power amp stages for low impedance headphones, I can reduce the variable resistor values and that one of the associated devices (by the capacitor values I need enhancing) down to values of 1-5 percent (this means 50 ohms instead 5000 ohms and as consequence very low sensitivity against unwanted microphonic effects).
Also a cuttoff selector is present (Luxman call this "Turnover Select")

Also the APD Holeman I will study exactly, if I have more time
http://homepage.mac.com/planet10/TLS...nPreManual.pdf
Why does the APT Holman preamp sound so good?
http://homepage.mac.com/planet10/TLS...nPreManual.pdf

RIAA Equalizer circuit
Phonograph preamplifier network with infrasonic cutoff response
Active load circuits
Phonograph preamplifier network with infrasonic cutoff response
Attached Images
File Type: jpg 001qrd.jpg (615.7 KB, 668 views)
Attached Files
File Type: pdf Luxman L550 Baxandall Equalizer.pdf (63.1 KB, 263 views)

Last edited by tiefbassuebertr; 8th September 2011 at 09:36 AM.
  Reply With Quote
Old 8th September 2011, 11:53 AM   #12
banat is offline banat  Serbia
diyAudio Member
 
Join Date: Dec 2009
Location: near Belgrade
Mr Douglas Self say here : Douglas Self Site

"Tone-controls cause an audible deterioration even when set to the flat position."
-This is usually blamed on "phase-shift". At the time of writing, tone controls on a preamp badly damage its chances of street (or rather sitting-room) credibility, for no good reason. Tone-controls set to 'flat' cannot possibly contribute any extra phase-shift and must be inaudible. My view is that they are absolutely indispensable for correcting room acoustics, loudspeaker shortcomings, or tonal balance of the source material, and that a lot of people are suffering sub-optimal sound as a result of this fashion. It is now commonplace for audio critics to suggest that frequency-response inadequacies should be corrected by changing loudspeakers. This is an extraordinarily expensive way of avoiding tone-controls.-

And I agree with him 100% !

Actually I have idea to experiment and implement this Luxman`` Duo Beta `` tone control circuit on the one of mine older conventional designed DIY PP tube power stereo Amp, simply returning GNFB loop from OPT outputs via tone control circuitry to the input tube differencial gain stage ,in the same manner as Luxman did on the countless number of SS integrated comercial Amps .

Best Regards
Attached Images
File Type: jpg l210schema.jpg (382.5 KB, 617 views)
  Reply With Quote
Old 9th September 2011, 09:59 AM   #13
diyAudio Member
 
sofaspud's Avatar
 
Join Date: Nov 2005
Location: San Antonio
200%
I built a tone control preamp to put in front of all the equipment that doesn't have them. I plan on at least one more. Thanks to all you contributors. There's a little bit of everything here.

PS I really like "ultimatest". Mind if I use it? Seriously.
__________________
It is error only, and not truth, that shrinks from enquiry. - Thomas Paine
  Reply With Quote
Old 9th September 2011, 11:31 AM   #14
banat is offline banat  Serbia
diyAudio Member
 
Join Date: Dec 2009
Location: near Belgrade


  Reply With Quote
Old 9th September 2011, 02:03 PM   #15
diyAudio Member
 
tiefbassuebertr's Avatar
 
Join Date: Jul 2005
Location: D-55629 Schwarzerden
Quote:
Originally Posted by Zero D View Post
@ tiefbassuebertr
I've always known him as Peter Baxandall, now I know his middle name
have a look to this attachement here.

I am looking for the cover image of this book:
Low-cost high-quality amplifier, with alternative pre-amplifiers - author: Peter James Baxandall - go to
Low-cost high-quality amplifier ... - Google Books
Who can upload this ??
Attached Files
File Type: pdf Baxandall, Peter James - In Memoriam JAES_V44_9_PG796.pdf (135.3 KB, 206 views)

Last edited by tiefbassuebertr; 9th September 2011 at 02:08 PM.
  Reply With Quote
Old 9th September 2011, 02:15 PM   #16
diyAudio Member
 
sofaspud's Avatar
 
Join Date: Nov 2005
Location: San Antonio
Try here.
__________________
It is error only, and not truth, that shrinks from enquiry. - Thomas Paine
  Reply With Quote
Old 9th September 2011, 02:25 PM   #17
diyAudio Member
 
tiefbassuebertr's Avatar
 
Join Date: Jul 2005
Location: D-55629 Schwarzerden
Quote:
Originally Posted by sofaspud View Post
Try here.
Thank you very much
Attached Files
File Type: pdf P.J. Baxandal low cost preamp......pdf (13.6 KB, 276 views)
  Reply With Quote
Old 17th September 2011, 06:04 AM   #18
ontoaba is offline ontoaba  Indonesia
diyAudio Member
 
ontoaba's Avatar
 
Join Date: Nov 2009
Location: Kudus, Malang, Dieng
Quote:
Originally Posted by sofaspud View Post
200%

PS I really like "ultimatest". Mind if I use it? Seriously.

Ultimatest (R) Integrated Power Amp.

Nice one!
  Reply With Quote
Old 27th October 2011, 07:41 AM   #19
diyAudio Member
 
Join Date: Jan 2011
My problem is that my tda 2040 is sounding good with tone control.but for this I used Tl072 which sounds quite noisy ,dont have other good chips too.My dth receiver aint that musical.Tda 2040 alone doesn't give me musical sound.So I have decided to go for standalone Lm1875 .I want mid range n treble frequencies .I will be very thankfull to u if u pl z provide any change from original circuit.How far can a passive tone control help?.
  Reply With Quote
Old 27th October 2011, 08:54 AM   #20
diyAudio Member
 
sofaspud's Avatar
 
Join Date: Nov 2005
Location: San Antonio
No changes necessary, AFAIK. The tone circuit output needs to see a high impedance. The 1M seen in the LM1875 datasheet app should be enough, or another op amp stage.
How far can it help? That can be hotly contested. I'm convinced tone controls can help SQ. And I follow the rule that if tone controls need to be turned way up, something else is wrong with the system. I have maybe +4dB on the treble and +1 for bass (I'm sure I have eardrum scar tissue from a bout with meningitis. Tinitus also. Hence the treble boost.). And they stay there. If a particularly worse recording gets played, I'm almost always reaching for the volume knob. That's rare though.
If you don't think tone controls are just for sissies, you might want to have a look at this thread: A usable tone control
__________________
It is error only, and not truth, that shrinks from enquiry. - Thomas Paine
  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
PC-based server versus network-based player hillbear PC Based 14 12th July 2011 12:13 AM
Please help with the designing of a passive crossover network! Big_Bill Multi-Way 74 17th July 2009 04:53 AM
i need preamp schematics w/o tone control or volume control hernanstafe Parts 7 30th January 2008 03:12 AM
enough gain for James tone stack PRNDL Tubes / Valves 17 21st December 2007 02:28 PM
Relay-based passive volume control project BrianGT Everything Else 110 1st March 2003 01:27 AM


New To Site? Need Help?

All times are GMT. The time now is 06:19 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