Pre-Amp ...... Help wanted with Circuit

[poynton]

Hi All,

I am looking for a circuit I have seen somewhere !!

I can only describe it as using NPN/PNP pairs in a cross coupled circuit with a +/- supply rail in a sort of diamond configuration and symmetrical.

Any ideas?

Thanks
Andy

[forr]

Hi Poynton,
You may refer to Dick Marsch' or Hafler circuits, two NPN and two PNP, low distorsion.

[mlloyd1]

based on what i think you're saying, i agree with forr ...
go to the hafler site and look for the DH101 preamp manual.
is that what you mean?

mlloyd1

[poynton]

Hi.

Thanks for that suggestion.

The RIAA section looks like what I was thinking of although what I had in mind was a buffer.

Andy

[poynton]

Originally posted by forr
Hi Poynton,
You may refer to Dick Marsch' or Hafler circuits, two NPN and two PNP, low distorsion.

I cannot find any references to " Dick Marsch" here or on Google.

Anyone?



Andy

[lineup]

Originally posted by poynton
I cannot find any references to " Dick Marsch" here or on Google

Try Dick Marsh or Richard Marsh
If you search with www.google.com or here in forum http://www.diyaudio.com/forums/search.php

He appears to have this Website: marshsounddesign.com
with products like:


Mr. Marsh is also very well known in Audio for this work,
together with some of the world's leading amplifier designers:
Walt Jung or Walter G. Jung and our own John 'JC' Curl
Picking Capacitors - Walter G. Jung and Richard Marsh, 1980
http://www.reliablecapacitors.com/pickcap.htm

Omitted factors in audio circuit design
John Curl

This paper appears in: Acoustics, Speech, and Signal Processing, IEEE International Conference on ICASSP '78.
Publication Date: Apr 1978
Volume: 3, On page(s): 263- 266

Abstract
Traditional measurements of audio amplifiers use test signals that do not represent conditions of actual use.

TIM measurement is one factor in improving the correlation between audible and measurable differences in circuitry.
Additionally, many circuits incorporate non-linear elements that appear to be distortionless at conventional measurement frequencies, but can be significant sources of distortion when subsonic or supersonic frequencies are included.

This paper describes some of these non-linear elements and their effects on actual circuit performance.

John Curl & Walt Jung: A Real-Time Signal Test for Capacitor Quality, 1985
http://waltjung.org/PDFs/Picking_Capacitors_1.pdf
http://waltjung.org/PDFs/Picking_Capacitors_2.pdf

Walt Jung - Classic Articles
Welcome to Walt Jung website


Lineup