I am trying to fix a ZYX Artisan phono stage which has a channel imbalance and it looks to me that the trim pots in the output rca’s are. I cannot even measure the resistance value with certainty. They measure sometimes in the order of 10 ohms and might look that momentarily measure 3 or 4 times that.
So, which nominal value resistance of suitable trim pots would be ok to trim volume in the order of 3db in a phono stage? Thanks.
So, which nominal value resistance of suitable trim pots would be ok to trim volume in the order of 3db in a phono stage? Thanks.
If this is a solid state unit with a pot at the output, use a 10k pot.
To reduce the output level by -3dB (x0.707), you can use linear pots.
They will track better than audio taper pots, be more accurately adjustable,
and are more readily available.
To reduce the output level by -3dB (x0.707), you can use linear pots.
They will track better than audio taper pots, be more accurately adjustable,
and are more readily available.
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It is very unusual for a phono preamp to have volume trims on the Output. Normally gain is trimmed in the amplifier.
But this preamp is $1000-$2000 so I have never seen one.
But this preamp is $1000-$2000 so I have never seen one.
The sloppy workmanship, and the solder flecks remaining that could detach and risk damage,
would suggest otherwise. Perhaps you should contact the mfr. about this. This was purchased used?
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Can we see the whole thing? I would doubt the provenance (it looks like a first time kit build).
Could you perhaps take a picture of the entire circuit board? Perhaps there's a reason for the pots. Normally they carefully select their resistors, so a relatively cheap pot doesn't make sense (perhaps to match the cartridge's L/R output, if you could hear the imbalance?)
They claim that they hand wind at least some of the resistors.
I don't think the sloppy work and dubious mounting could be original.
The unit was "salvaged" from an estate
by a friend. Had been stored, abandoned, in a hot humid room for a long time. The original batteries were blown up and sulfated as well as the circuit board.
He took it to a tech and the tech replaced the battery pack and cleaned everything up. He used the same battery types as the original had. I am not sure if he installed the pots in the outputs or if they are original. I''ll try to check. After that the friend got tired of it and passed the unit to me to see what I could do with it.
There is a misbalance in the channel outputs, but I am not sure if it is the unit or the cartridge I am using - bought a used in ebay Denon DL 103-.
With the pots I am able to balance the outputs for a while, but the imbalance appears again after a while...I am experimenting with analog... as you can see, but it seems that I would need to get a new cartridge and phono section... to ceck it out.
This unit used to be sold for $5,000 if you can believe that. The few reviews that I found mention that it is good sounding unit, albeit the workmanship does not look too appealing. Apparently its production has ceased.
And, supposedly the unit could not be user opened, prohibition pollcy by the manufacturer under order of "execution" it seems..... I contacted the distributor in the USA with the question regarding the pots and he did not want to answer because it was opened...
by a friend. Had been stored, abandoned, in a hot humid room for a long time. The original batteries were blown up and sulfated as well as the circuit board.
He took it to a tech and the tech replaced the battery pack and cleaned everything up. He used the same battery types as the original had. I am not sure if he installed the pots in the outputs or if they are original. I''ll try to check. After that the friend got tired of it and passed the unit to me to see what I could do with it.
There is a misbalance in the channel outputs, but I am not sure if it is the unit or the cartridge I am using - bought a used in ebay Denon DL 103-.
With the pots I am able to balance the outputs for a while, but the imbalance appears again after a while...I am experimenting with analog... as you can see, but it seems that I would need to get a new cartridge and phono section... to ceck it out.
This unit used to be sold for $5,000 if you can believe that. The few reviews that I found mention that it is good sounding unit, albeit the workmanship does not look too appealing. Apparently its production has ceased.
And, supposedly the unit could not be user opened, prohibition pollcy by the manufacturer under order of "execution" it seems..... I contacted the distributor in the USA with the question regarding the pots and he did not want to answer because it was opened...
To check the imbalance, all you have to do is reverse the two RCA plugs from the turntable,
left for right. If the problem switches sides, it is in the turntable, not the phono stage.
If the imbalance is in the phono stage, it should be repaired. There would probably be other
problems than just the imbalance.
left for right. If the problem switches sides, it is in the turntable, not the phono stage.
If the imbalance is in the phono stage, it should be repaired. There would probably be other
problems than just the imbalance.
You could also measure the coils of your Denon with a DIGITAL multimeter to check if there's an imbalance.