#1
Hey all,

the pot on my PGM301 split a while back so I had to replace it. I don't know if you're familiar but the PGM has only one control for tone and volume but it's extremely versatile and really cleans the guitar when you roll it back.

Anyways, since changing it, it doesn't seem to do it anymore. When I roll back the volume nothing much happens till the last 15% or so of the turn, where it suddenly loses volume and sounds like someone rolled all the tone off. Now, I'm at a bit of a loss as to why as I'm not that sharp on guitar electronics really.

The pot I used, or was rather told to use, was a B500K pot.

Thanks in advance.
Ibanez PGM301
Ibanez GRG170DX
Fender Telecaster MiJ - 1986
Swing T-Through

Ibanez TS9DX
Sovtek Small Stone - c.1985
EHX Big Muff
Kimbara Wah - c.1974
Boss GE-7

Orange Rocker 30 Combo

http://www.myspace.com/paythelay
#2
what was the previous pot? 250 or 500k? plus, was it a mini pot?
Ibanez RG321MH (Air Classic/Tone Zone)
Fernandes Telecaster (Twang King/stock bridge pickup)
Blackstar HT-20 (Scumback 55 speaker/ Tung Sol tubes)
TC Electronic Nova Repeater
Lava Cables Clear Connect, Soar and Mini ELC
#3
It was a 500K and yeah, the pot was a lot smaller.
Ibanez PGM301
Ibanez GRG170DX
Fender Telecaster MiJ - 1986
Swing T-Through

Ibanez TS9DX
Sovtek Small Stone - c.1985
EHX Big Muff
Kimbara Wah - c.1974
Boss GE-7

Orange Rocker 30 Combo

http://www.myspace.com/paythelay
#4
well, thats it. it was a 500k mini pot. since the it's smaller, a small rotation would mean a great difference in volume. as for your current pot, since it's bigger than the previous one, ait would need a bigger rotation for a small change in volume. a simple concept in physics.

so i suggest you get a pot similar to the previous one. oh, i almost forgot, is there a letter engraved after the 500K?
Ibanez RG321MH (Air Classic/Tone Zone)
Fernandes Telecaster (Twang King/stock bridge pickup)
Blackstar HT-20 (Scumback 55 speaker/ Tung Sol tubes)
TC Electronic Nova Repeater
Lava Cables Clear Connect, Soar and Mini ELC
#5
It's 500K B, or B500K, one of the two.

Hmm, it's not just the amount of rotation. The rotation amount is similar in both, it's just that I don't gain the same clarity that I used to by rolling off the volume and infact, feel very little effect till the last part of the cycle.
Ibanez PGM301
Ibanez GRG170DX
Fender Telecaster MiJ - 1986
Swing T-Through

Ibanez TS9DX
Sovtek Small Stone - c.1985
EHX Big Muff
Kimbara Wah - c.1974
Boss GE-7

Orange Rocker 30 Combo

http://www.myspace.com/paythelay
#6
then just replace it with the another B500K mini pot and see what happens.
Ibanez RG321MH (Air Classic/Tone Zone)
Fernandes Telecaster (Twang King/stock bridge pickup)
Blackstar HT-20 (Scumback 55 speaker/ Tung Sol tubes)
TC Electronic Nova Repeater
Lava Cables Clear Connect, Soar and Mini ELC
#7
sounds like a taper problem, make sure the pot has linear taper, that allows for smooth volume roll off, lots of cheaper pots have log tapers so there isn't much notice in volume drop-off until you really turn it down.
'08 Gretsch White Falcon
'98 Fender USA Deluxe Tele
'79 Greco Les Paul Standard
Airline Stratotone Crafter GAE8

A bunch of funky pedals

Handwired 50 Watt Plexi Lead Clone w/ Orange 4x12
#8
You need an A500k pot or 500k Log pot and a 330p capacitor across the hot in and hot out on the pot for the volume.
and a B500k or 500k linear pot and probably 47nF capacitor for the tone control. The A means its emulated logarithmic (just like our ears response to sound) the 330p capacitor is for keeping the pickups treble at low pot rotation (i.e. low volume) was there a capacitor on the original pot?
#9
Yeah, I soldered the capacitor from the original to the one I put in. I think the problem is as you suggested and I had a feeling of. It's a B500K which I was given to install, but I need an A500k? It controls both the tone and the volume, as you can see here:

http://uk.youtube.com/watch?v=CIl3Qtjusqs
3 minutes in.

So an A500K would be right?
Ibanez PGM301
Ibanez GRG170DX
Fender Telecaster MiJ - 1986
Swing T-Through

Ibanez TS9DX
Sovtek Small Stone - c.1985
EHX Big Muff
Kimbara Wah - c.1974
Boss GE-7

Orange Rocker 30 Combo

http://www.myspace.com/paythelay
#10
Quote by Kurapica
Yeah, I soldered the capacitor from the original to the one I put in. I think the problem is as you suggested and I had a feeling of. It's a B500K which I was given to install, but I need an A500k? It controls both the tone and the volume, as you can see here:

http://uk.youtube.com/watch?v=CIl3Qtjusqs
3 minutes in.

So an A500K would be right?

I thought you had a tone control installed in your PGM301:P my bad
but the volume control doesnt control the tone..that sound comes from pauls control of the instrument and his amp set-up i.e the heavier, bassier sound comes when he steps on a tubescremer and clean glassy sound when he turns the pedal off and turns the volume down.

The A500k would be right, its used on all humbucker volume controls. dont forget the cap though
#11
Quote by Entrant_21
I thought you had a tone control installed in your PGM301:P my bad
but the volume control doesnt control the tone..that sound comes from pauls control of the instrument and his amp set-up i.e the heavier, bassier sound comes when he steps on a tubescremer and clean glassy sound when he turns the pedal off and turns the volume down.

The A500k would be right, its used on all humbucker volume controls. dont forget the cap though


Nah, it does control the tone a bit, it's sort of all in one. Like in that video he's not changed the pedals just rolled the volume/tone control back. But yeah, so you reckon that the A500 would do the trick?

Thanks for the help man, I had a feeling that it'd be that but didn't want to aimlessly buy another pot haha.
Ibanez PGM301
Ibanez GRG170DX
Fender Telecaster MiJ - 1986
Swing T-Through

Ibanez TS9DX
Sovtek Small Stone - c.1985
EHX Big Muff
Kimbara Wah - c.1974
Boss GE-7

Orange Rocker 30 Combo

http://www.myspace.com/paythelay
#12
Quote by Kurapica
Nah, it does control the tone a bit, it's sort of all in one. Like in that video he's not changed the pedals just rolled the volume/tone control back. But yeah, so you reckon that the A500 would do the trick?

Thanks for the help man, I had a feeling that it'd be that but didn't want to aimlessly buy another pot haha.


Yeah it does control the tone a bit..but only to keep treble frequencies unattenuated:P watch his foot after the heavy intro ..i think its around 3:00 he steps on the pedal and rolls the volume I've seen so many PG videos and im a massive fan! I know his rig!

But yup the A500k would do the trick, I reccomend a CGE brand pot. theyre so smooth and never get scratchy!