diyAudio (
-   Analog Line Level (
-   -   Balanced XLR source RIAA (

Stee 18th July 2008 05:39 PM

Balanced XLR source RIAA
2 Attachment(s)
see my idea to have perfect balanced signal
from MC cartridge
with new cable
and four channel RIAA

analog_sa 18th July 2008 08:58 PM

This doesn't fill me up with confidence.

mlloyd1 18th July 2008 09:28 PM

indeed ...

that is a lot of components to match and there are likely more elegant and higher performance approaches available.

but, who am i to say. :)
give it a go and let us know how it works out ...

best regards,

Stee 19th July 2008 10:15 AM

Balanced Source is the Way
2 Attachment(s)
yes sure

I will test and upgrade...

really the news is
connect MC in balanced mode

to have better performance
also for filter and other chain...

SY 19th July 2008 11:24 AM

Running the cartridge balance is a very good idea (says the guy who runs his cartridge balanced). These are just not good implementations. The second one will have degraded noise performance.

There are (to my knowledge) two good ways to do it. One is to build a fully differential phono input, the other is to use a transformer at the input and run the primary balanced. The secondary can then drive the input of a conventional single-ended stage. You get 99% of the balanced advantage that way.

Stee 19th July 2008 11:34 AM

thanks <SY>
do you have a schematic of fully differential one?
this is just a project with OPA1632

SY 19th July 2008 11:39 AM

Only with tubes, but I'll bet there's a transistorized one around the forum somewhere. The "search" function is your friend.

Here's an example of a tube one:

edit: The one you linked to looks much better.
edit edit: "Better" than the first one, not better than the Vacuum State one; sorry to be ambiguous.

analog_sa 19th July 2008 11:44 AM

You can get some good, working ideas here

Stee 19th July 2008 06:30 PM

thesis: balancing improves
2 Attachment(s)
to see if the hypothesis is correct
I did a simple test that anyone can repeat at home


listen a preferred song only from one channel
for example the right channel

turn off everything

connect the left channel wire on cartridge instead of ground wire
and connect the negative pole of right loudspeaker
on left output of the amplifier

push on everything

hear the same song...

I believe the difference is very significant :

the sound is more dynamic
treble are more crystalline
the noise is reduced!

analog_sa 19th July 2008 06:37 PM

Lovely picture :)

It seems you are listening to the entire chain balanced now, not just the phono. Difficult to know how much of the improvement is due to the phono stage but interesting all the same. No hum?

All times are GMT. The time now is 02:39 AM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 18.75%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio