When I am listening to my unit at very low volume levels, the right channel is slightly louder than the left channel until I turn it up a little more where they even out. What would be the cause of this?
3 posters
PAS-3 uneven L-R volume at low levels
lobby- Posts : 18
Join date : 2011-02-15
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Last edited by PeterCapo on Wed Dec 02, 2020 5:46 pm; edited 1 time in total
lobby- Posts : 18
Join date : 2011-02-15
PeterCapo wrote:If you have the original volume pot, it is probably the culprit.
What are my options for replacement. Not looking to throw a ton of money around on a pot, just want even volume at low levels.
Will something like this work fine?
https://www.radioshack.com/products/radioshack-100k-dual-ganged-stereo-volume-control?variant=5717293381
peterh- Posts : 1833
Join date : 2012-12-25
Location : gothenburg, sweden
No.lobby wrote:PeterCapo wrote:If you have the original volume pot, it is probably the culprit.
What are my options for replacement. Not looking to throw a ton of money around on a pot, just want even volume at low levels.
Will something like this work fine?
https://www.radioshack.com/products/radioshack-100k-dual-ganged-stereo-volume-control?variant=5717293381
See http://www.tubenirvana.net/pas3-spare-parts.html for suggestions of working ones.
An alternative is to make a signal damper ( 470k in series and 270k to ground on each output to
the poweramp.) That way your volume won't be close to it's ends where it is most inaccurate.
lobby- Posts : 18
Join date : 2011-02-15
peterh wrote:No.lobby wrote:PeterCapo wrote:If you have the original volume pot, it is probably the culprit.
What are my options for replacement. Not looking to throw a ton of money around on a pot, just want even volume at low levels.
Will something like this work fine?
https://www.radioshack.com/products/radioshack-100k-dual-ganged-stereo-volume-control?variant=5717293381
See http://www.tubenirvana.net/pas3-spare-parts.html for suggestions of working ones.
An alternative is to make a signal damper ( 470k in series and 270k to ground on each output to
the poweramp.) That way your volume won't be close to it's ends where it is most inaccurate.
He has 3 different pots all at about $30. Which one is ideal?
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Last edited by PeterCapo on Wed Dec 02, 2020 5:47 pm; edited 2 times in total (Reason for editing : Correction.)
peterh- Posts : 1833
Join date : 2012-12-25
Location : gothenburg, sweden
The "damper" could easily be implemeted inside the pas-3, solder the 470k in series with the
cable to the output rca connector, and make the loading resistor from the rca connector to ground.
That way your existing pot don't need replacing but will find a new "working area" .
cable to the output rca connector, and make the loading resistor from the rca connector to ground.
That way your existing pot don't need replacing but will find a new "working area" .
Guest- Guest
PeterCapo wrote:You could "try" the Radio Shack pot and see how it does. I had one of those and did not think much of it. But, you could get lucky and get one that tracks reasonably well.
Not familiar with peterh's "signal damper," so cannot comment on it.
The tube Nirvana pots, if I correctly read the listing, do not have loudness taps (please correct me if I am wrong). In the PAS in particular, if you don't have loudness taps the volume will increase very rapidly with much less clockwise rotation of the pot, making it difficult or outright impractical to listen at lower volume levels.
If you change the value of the pot from the original 250K to 100K, it might affect the phono section a little, but I don’t think too much. Am a little rusty on this point, but have a read here: http://www.audioregenesis.com/documents/PAS_Phono.pdf
I got one of these and it does pretty well (note I disconnected the phono section in my PAS): http://www.ebay.com/itm/1-X-MADE-JAPAN-ALPS-RK27-SERIES-100K-STEREO-VOLUME-CONTROL-POT-LOUDNESS-/301456600201?hash=item463036ac89 If that link doesn’t work, let me know and we’ll try again.
At low volume levels, it might be difficult for anything but an expensive stepped setup to keep the channels even. Possibly might not do better in terms of low volume channel tracking with any of these, but it's definitely worth a try.
Peter
in my experience, using a pot without the loudness connection makes no difference in the control over the volume. You will still get the same amount of volume control, ie, 'not shorter or longer'.
Most PAS2/3 owners who upgrade do away with the loudness function as well as the mono/stereo switch. It is completely taken out of the circuit. If you wish to retain tone controls, then either upgrade with our tone control upgrade kit, which consists of four new pots and a new set of capacitors, or go with the TCLA upgrade kit, together with either the Z-Mod PC6 or Z-Mod PH10 phono preamp upgrades.
If you do go down the TCLA road, you must also upgrade the power supply, our Regulated Power supply v18 or v19, as the older style power supply and the PA211 transformers will not be able to adequately supply the extra tubes filament requirements as well as the B+.
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Last edited by PeterCapo on Wed Dec 02, 2020 5:47 pm; edited 1 time in total
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no, with our line stage. Have not had any negative feedback whenever someone went the non loudness volume control way, be it our line stage or perhaps original.
Roy Mottram- Admin
- Posts : 1839
Join date : 2008-11-30
Lobby,
that's what balance controls are for. Even most $30 volume controls I've tested have very inaccurate tracking, especially at less than 1/2 volume,
it's common to see 7-10% imbalance. I've got 21 step volume attenuators that are within 1% tracking over the entire range, $30.
that's what balance controls are for. Even most $30 volume controls I've tested have very inaccurate tracking, especially at less than 1/2 volume,
it's common to see 7-10% imbalance. I've got 21 step volume attenuators that are within 1% tracking over the entire range, $30.
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