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Old 21st July 2011, 10:09 AM   #751
milosz is offline milosz  United States
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WEIRD NEW PROBLEM WITH PEARL

This is a strange one.

With Shure V-15 / type III into the Pearl all is well. Sounds good, at least as good as a V15 sounds anyway.

With Dynavector 10x5 into Pearl, there is a serious (9 dB) channel imbalance at 1,000 Hz.

With Dynavector 10x5 into Bottlehead Eros, or Parasound Z-Phono, NO CHANNEL IMBALANCE.

So, for some reason the Dynavector shows a big channel imbalance into the Pearl, but not into other preamps; while using the V15 with the Pearl shows less than 1 dB of imbalance on the 1 kHz band on my test LP.


?????

Double-checked my input load resistors, they are 47k, this should work great with the Dynavector.

Not sure I can understand how this could even be possible, outside of some odd loading effect?

It's too bad, too, because the Pearl is really SUPER QUIET compared to the Bottlehead and the Parasound doesn't really sound all that great.
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Old 21st July 2011, 10:23 AM   #752
nar is offline nar
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Quote:
Originally Posted by milosz View Post
WEIRD NEW PROBLEM WITH PEARL

This is a strange one.

With Shure V-15 / type III into the Pearl all is well. Sounds good, at least as good as a V15 sounds anyway.

With Dynavector 10x5 into Pearl, there is a serious (9 dB) channel imbalance at 1,000 Hz.

With Dynavector 10x5 into Bottlehead Eros, or Parasound Z-Phono, NO CHANNEL IMBALANCE.

So, for some reason the Dynavector shows a big channel imbalance into the Pearl, but not into other preamps; while using the V15 with the Pearl shows less than 1 dB of imbalance on the 1 kHz band on my test LP.


?????

Double-checked my input load resistors, they are 47k, this should work great with the Dynavector.

Not sure I can understand how this could even be possible, outside of some odd loading effect?

It's too bad, too, because the Pearl is really SUPER QUIET compared to the Bottlehead and the Parasound doesn't really sound all that great.
If it's not a cable/solder issue, try experimenting other loading values, tech datasheet says > 1k, so you can experiment from that value If problem is still, maybe it's a cartridge tracking problem on the cut groove, test LPs are known to be excellent to reveal those kind of things.

Maybe confirm with another Dynavector that problem is still. Maybe unmount - mount of cartridges can lead to connections problems, those are tiny wires after all

It's rather an external problem not Pearl internal.

Regards,

nAr
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Last edited by nar; 21st July 2011 at 10:26 AM.
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Old 21st July 2011, 10:32 AM   #753
milosz is offline milosz  United States
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Quote:
Originally Posted by nar View Post
If problem is still, maybe it's a cartridge tracking problem on the cut groove, test LPs are known to be excellent to reveal those kind of things.

Maybe confirm with another Dynavector that problem is still. Maybe unmount - mount of cartridges can lead to connections problems, those are tiny wires after all

It's rather an external problem not Pearl internal.

Regards,

nAr
Well, I would think if it were tracking / setup, cartridge lead connection issue, etc, then the channel imbalance problem would be the same with any phono preamp. However, using the 10x5 with Parasound Z-Phono or Bottlehead Eros phono stages, the Dynavector has NO channel imbalance problem... the only cartridge / phono stage combination that shows this problem is the Dynavector / Pearl.


...and the Shure with the Pearl, channels are very well balanced.

A real head scratcher.
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Old 21st July 2011, 10:48 AM   #754
nar is offline nar
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Quote:
Originally Posted by milosz View Post
Well, I would think if it were tracking / setup, cartridge lead connection issue, etc, then the channel imbalance problem would be the same with any phono preamp. However, using the 10x5 with Parasound Z-Phono or Bottlehead Eros phono stages, the Dynavector has NO channel imbalance problem... the only cartridge / phono stage combination that shows this problem is the Dynavector / Pearl.


...and the Shure with the Pearl, channels are very well balanced.

A real head scratcher.
Just to be sure; you use same turntable for all tests ? just swapping cartridges ? and same phono cord between turntable and phono pre ?

Best,

nAr
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"... Audio needs the thinnest wire ..." Rowan McCombe ... I hear it !!!
"Just 'cause they can't hear or sense it themselves doesn't mean you can't !" Allen Wright Allen was right ...
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Old 21st July 2011, 11:10 AM   #755
milosz is offline milosz  United States
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Quote:
Originally Posted by nar View Post
Just to be sure; you use same turntable for all tests ? just swapping cartridges ? and same phono cord between turntable and phono pre ?

Best,

nAr

Yes
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Old 21st July 2011, 11:45 AM   #756
milosz is offline milosz  United States
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Quote:
Originally Posted by nar View Post
Just to be sure; you use same turntable for all tests ? just swapping cartridges ? and same phono cord between turntable and phono pre ?

Best,

nAr
Yes

Same cables, turntable, same everything just different combinations of phono cartridge and preamp
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Old 22nd July 2011, 09:50 AM   #757
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Hi Gents ,

just got my boards and bits ..... can some one guide me to BOM and the schematic please ... ?

Cheers , Rich
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Old 22nd July 2011, 10:22 AM   #758
nar is offline nar
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Originally Posted by milosz View Post
Yes

Same cables, turntable, same everything just different combinations of phono cartridge and preamp
Maybe Wayne can come and rescue us !!!
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"Just 'cause they can't hear or sense it themselves doesn't mean you can't !" Allen Wright Allen was right ...
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Old 22nd July 2011, 10:41 AM   #759
milosz is offline milosz  United States
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Does he read these forum posts?
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Old 22nd July 2011, 10:44 AM   #760
milosz is offline milosz  United States
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Quote:
Originally Posted by richluvsound View Post
Hi Gents ,

just got my boards and bits ..... can some one guide me to BOM and the schematic please ... ?

Cheers , Rich
http://www.passdiy.com/pdf/pearlphono.pdf <= ORIGINAL PEARL

http://www.passdiy.com/pdf/PEARL%202.pdf <= PEARL 2

-Bill
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