Balanced XLR source RIAA

[jackinnj]

This circuits has very poor CMRR at low frequency. And C1/C5 pairs have to be well matched in order to avoid further CMRR degradation and to keep theoretical 40dB CMRR.
//That's why I choose OPA1632 into 2nd position.

I have a name for your RIAA preamp -- the Hunga-RIAA-ton -- after the eponymous record label.

In 1981 there were a series of articles in TAA which described a mod for the Marantz 7 -- they called the RIAA section the DRIAAgon.

I can't find Scott's post...search under members.

 

[jackinnj]

> Differential DIY OPAMP -- Scott Wurcer posted under "Measuring Low Noise"

Can you kindly post a link please.


Thanks,
Patrick

http://www.diyaudio.com/forums/attachment.php?s=&postid=1603576&stamp=1220707608

 

[Stee]

sorry don't have schematic

http://nadelectronics.com/products/hifi-amplifiers/PP-2-Phono-Preamplifier/images

 

[mlloyd1]

Re: sorry don't have schematic

courtesy of algar emi:

http://www.diyaudio.com/forums/showthread.php?postid=712445#post712445

mlloyd1

http://nadelectronics.com/products/hifi-amplifiers/PP-2-Phono-Preamplifier/images

 

[Stee]

Just A Picture

NAD PP2 VER.5 IS MADE WITH

A970 C2240 -->A PAIR FOR EACH CHANNEL (there is MM/MC in)
PLUS ONE OPA NE5532P

SEE PICTURE ON MY SITE
http://www.esafono.it/NAD_PP2_VER5B.jpg

if someone is able to make schematic from PCB picture ...
i can do that 😉

for this project you need double preamp (four channel HOT/COLD)

 

[Stee]

BALANCED POWER RIAA

the same OPA of PP2 can drive
a double copule of 2SA1930-2SC5171
(again 4 channel) to have a complete amplifier...