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Old 6th December 2010, 10:44 PM   #3811
SY is offline SY  United States
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Allen's been doing the balanced deal since 1995.

Disconnect those leads from the preamp that's shorting them together in your example and, hey presto, there's no continuity!
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Old 6th December 2010, 11:30 PM   #3812
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If the preamp phono input is shorting the shields together you can bet your life the input is single ended. 99% of phono stages will do this.
End of story I'm out of this off topic disscusion, take it to the Analogue Source forum where it belongs.

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Old 6th December 2010, 11:37 PM   #3813
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Didn't quite get the point? You said

Quote:
And don't think for a minute that cartriges are balanced because they have 4 wires, 2 of the wires are earthed to the shielded cable, and only have one hot per channel not 2 +&- like balanced should be, otherwise they would have 6 wires.
That's incorrect. And I think you've now moved to the correct statement that most phono preamps do NOT take advantage of the inherently balanced nature of most cartridges, and are configured with single ended inputs. NOT the same thing as saying that cartridges aren't balanced and that one needs six leads to make them balanced.

With that, I'll step back out of the thread and let you get in back on topic. My apologies for the distraction, but a common misconception needed to be straightened out.
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Old 7th December 2010, 12:36 AM   #3814
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Quote:
Originally Posted by SY View Post
Didn't quite get the point? You said



That's incorrect. And I think you've now moved to the correct statement that most phono preamps do NOT take advantage of the inherently balanced nature of most cartridges, and are configured with single ended inputs. NOT the same thing as saying that cartridges aren't balanced and that one needs six leads to make them balanced.

...
I thought we were talking about phono preamps all the time. Isn't that what George was talking about all the time?
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Old 7th December 2010, 01:57 AM   #3815
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Quote:
Originally Posted by soongsc View Post
I thought we were talking about phono preamps all the time. Isn't that what George was talking about all the time?
That's what I was trying to get accross, 99% of owners are listening to their cartridges in single ended hookup to their phono stages.
Some people just can't see the forest through the trees.

Cheers George
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Old 7th December 2010, 03:40 AM   #3816
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Originally Posted by georgehifi View Post
That's what I was trying to get accross, 99% of owners are listening to their cartridges in single ended hookup to their phono stages.
This is obviously because :
1-Most of the customers don't know what can be done technically speaking,
2-There is a few of these balanced devices on the phono market
3-For high output level MM cartridges (majority of the market) this is not advisable...

But for MC devices it's like for mikes : the balanced version (current mode) will achieve better results for the reasons already detailed above.
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Old 7th December 2010, 11:06 AM   #3817
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Originally Posted by ondesx View Post
This is obviously because :
...
3-For high output level MM cartridges (majority of the market) this is not advisable...

But for MC devices it's like for mikes : the balanced version (current mode) will achieve better results for the reasons already detailed above.
Even mm cartridges that have high output level is still pretty low compared to normal line level. If they don't run in current mode, then the 47K impedance will end up pretty much like I have shown.
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Old 7th December 2010, 11:28 AM   #3818
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3-For high output level MM cartridges (majority of the market) this is not advisable...

Damn! I wish you'd told me that twenty years ago. There was Analog Devices (and PMI) producing the 2016 differential audio amp chip and the circuit designer explaining how to set it up for balanced input from MM cartridges and me using an off-the-shelf Goldring cartridge (none of your worth-twice-its-weight-in-gold MCs).

Worse, there was me thinking all these years that it probably sounded rather better than single-ended.

Ah well, we live and learn.
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Old 7th December 2010, 01:01 PM   #3819
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Originally Posted by Ryelands View Post
[i]
Damn! I wish you'd told me that twenty years ago. There was Analog Devices (and PMI) producing the 2016 differential audio amp chip and the circuit designer explaining how to set it up for balanced input from MM cartridges and me using an off-the-shelf Goldring cartridge (none of your worth-twice-its-weight-in-gold MCs).
Worse, there was me thinking all these years that it probably sounded rather better than single-ended.
Ah well, we live and learn.
To close definitely this out off topic it appears that :
MC-cartridges are balanced current generators matching best with balanced current amplifiers
MM-cartridges are voltage generators matching best with voltage amplifiers

If you want more info, please feel free to ask to the people of Aqvox.

What I personally know is that whatever the voltage output level of the MC models, even for the lowest, the value of the current remains more or less the same... Using balanced designs in current mode, seems the best method to interface this device.

Last edited by ondesx; 7th December 2010 at 01:07 PM.
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Old 7th December 2010, 04:41 PM   #3820
tvi is offline tvi  Australia
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Quote:
Originally Posted by Joachim Gerhard
When i go balanced i prefer the INA topology. See my FPS MC Phonostgae in Jan Diddens Linear 0 compilation. It is balanced from input to output, even the RIAA is fully balanced. Comes with a 3dB noise panalty with the same amount of input devices
from here

Quote:
Originally Posted by rjm
With a balanced circuit, you have two input stages, each one seeing half the input signal voltage that the input of an unbalanced stage would see. The gain of each input stage is the same of course. So, all things being equal you end up with twice the noise at the output. Which being random sums to 1.4 times the noise, but thats still a 3 dB hit on your noise floor.
from here


rgds
jms
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