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thom
Copper Member
United Kingdom
10 Posts |
 Posted - 11/04/2009 : 12:37:27
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Okay, so I recently purchased a BOSS PS-2. Thing is, I think it might be broken/modified; I've heard that the PS-2 does really nice oscillations (like at the end of Slowdive's "Souvlaki Space Station" and of Mono's "Pure as Snow (Trails of the Winter Storm)"), but mine doesn't seem to oscillate at all, on any of the delay or pitch shifting settings, even with the feedback control completely maxed out.
I think I may be having the same problem as the individual in this thread:
http://www.bossarea.com/forum/topic.asp?TOPIC_ID=2287
If so, could someone tell me how to locate adjust my PS-2's trim pots? |
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Dr. Bob
Moderator
Australia
6593 Posts |
Posted - 11/04/2009 : 13:44:01
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Hi thom
First of all welcome to the forum from Australia.
There are some good close-up pics of the PS-2 here in the "Pedal Internals" thread, posted by Mesjoggah:
http://www.bossarea.com/forum/topic.asp?TOPIC_ID=4147&whichpage=17
In the second picture you will see the VR5 trim pot next to a small resistor marked R27
The other trim pot VR4 is in line with VR5 but at the other end of the board.-
- The end with the wires, & slightly closer to the centre line of the board, next to a vertically mounted resistor marked R2 & Cap C3.
(This is not visible in the pictures).
The trim pot setup procedure is in your own hands, & at your own risk.
As we don't have any idea of your skill level.
(simply put, try not to short/fry anything while it's apart).
The official factory setup procedure for VR-4 & VR-5
(The service guys said I'll have to kill you after you read this) - Just Joking...
Use a good quality regulated 9VDC power supply. (NOT a Battery).
1/ Connect a good quality tuner like the (TU-12, TU-100)
it's better to use a frequency counter, connect either to the TUNER OUT jack.
You will also need a lead plugged into the input socket to turn it on
2/ Turn MODE to [4].
3/ Turn FINE/MANUAL fully clockwise and adjust VR5 for C# (277.18Hz).
4/ Turn FINE/MANUAL fully counterclockwise & adjust VR4 for B (61.735Hz).
5/ Non-Official step.
If none of this makes any sense don't attempt to adjust the trim pots.
You will not be able to just guess their settings.
Good Luck - enjoy.
If it breaks - we know nothing - you didn't read this here...
Regards Dr. Bob 
PS - It's always a good idea to place a mark, using a fine-tip marker pen,
on the trim pots before you attempt to adjust them.
That way, at least you'll have some idea as to where they were originally set.
(whether they were set correctly or not).
Regards again Dr. Bob
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Edited by - Dr. Bob on 11/04/2009 13:49:23 |
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thom
Copper Member
United Kingdom
10 Posts |
Posted - 11/05/2009 : 00:20:08
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quote:
Originally posted by Dr. Bob
1/ Connect a good quality tuner like the (TU-12, TU-100)
it's better to use a frequency counter, connect either to the TUNER OUT jack.
You will also need a lead plugged into the input socket to turn it on
2/ Turn MODE to [4].
3/ Turn FINE/MANUAL fully clockwise and adjust VR5 for C# (277.18Hz).
4/ Turn FINE/MANUAL fully counterclockwise & adjust VR4 for B (61.735Hz).
Thanks for the advice, I followed the instructions precisely, and managed to adjust VR5 to C# and VR4 to B, but there doesn't seem to be any apparent change. No oscillation, pedal still sounds quite quiet. Any idea what the problem might be? |
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thom
Copper Member
United Kingdom
10 Posts |
Posted - 11/07/2009 : 15:09:56
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| Anyone? Bueller? |
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Dr. Bob
Moderator
Australia
6593 Posts |
Posted - 11/07/2009 : 16:08:36
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quote:
Originally posted by thom
Anyone? Bueller?
Hi thom
I'm not familiar enough with the PS-2 to offer you more help.
Are you able to take, & upload some digital pics of both sides of the board & the wiring.
You did mention that you belive it has been modified.
We might be able to see if something has been obviously changed.
And we don't really know what we're dealing with, if it has been modified.
Perhaps the modifications were to stop it self oscillating?
Are you able to compare it with another unit, perhaps one from a friend, or one at a second hand store.
There are some other guys here that own PS-2's.
Perhaps they will offer to chime in & help.
Regards Dr. Bob
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thom
Copper Member
United Kingdom
10 Posts |
Posted - 11/09/2009 : 13:54:45
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quote:
Originally posted by Dr. Bob
quote:
Originally posted by thom
Anyone? Bueller?
Hi thom
I'm not familiar enough with the PS-2 to offer you more help.
Are you able to take, & upload some digital pics of both sides of the board & the wiring.
You did mention that you belive it has been modified.
We might be able to see if something has been obviously changed.
And we don't really know what we're dealing with, if it has been modified.
Perhaps the modifications were to stop it self oscillating?
Are you able to compare it with another unit, perhaps one from a friend, or one at a second hand store.
There are some other guys here that own PS-2's.
Perhaps they will offer to chime in & help.
Regards Dr. Bob
I don't have a digital camera, I'm afraid. Does anyone know if the VR4 and VR5 trim pots affect the Balance/Feedback on any (1 to 3) of the Delay modes? |
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Laurie
Double Platinum Member
Canada
4854 Posts |
Posted - 11/09/2009 : 16:18:41
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VR4 and VR5 are used to trim the master clock to the correct harmonic frequency (to give correct pitch shift). They don't have anything to do with feedback.
There is no control for feedback other than the external "Feedback" knob.
If you wanted to muck around with it (not recommended), you could try halving R20 - that would double the feedback signal size. Not sure what it would other than make the thing distort though.
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thom
Copper Member
United Kingdom
10 Posts |
Posted - 11/09/2009 : 23:03:02
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quote:
Originally posted by Laurie
VR4 and VR5 are used to trim the master clock to the correct harmonic frequency (to give correct pitch shift). They don't have anything to do with feedback.
There is no control for feedback other than the external "Feedback" knob.
If that is indeed true, then do you or anyone else know why my PS-2 is so frustratingly lacking in both volume and oscillations? As I mentioned before, there was someone who had what sounds like exactly the same problem as myself here. I wonder if they managed to alleviate the problem... |
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Topic |
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BOSS PS-2 Digital Pitch Shifter/Delay
