could someone help me out?

[earthhuman]

i need to replace the master volume pot on a crate b150 head i just bought and i dont know which to get. could someone help me? here is the schematic

http://www.crateamps.com/pdf/manuals/B150.pdf

[Mark Black]

From the schematic it looks like component designator P11, a 10KA (audio taper, 10K ohms).

I would try Crate & see if they will sell you one, since manufacturers often orders pots to their own spec (shaft-style, bushing-style, brackets, etc.).

Good luck!

[Enzo]

And the part number is right there on the schematic: 70-103-22

[earthhuman]

that part number means nothing to anyone but crate so it dosent really help me

[Bruce / Mission Amps]

that part number means nothing to anyone but crate so it dosent really help me

Does that mean you are trying to avoid buying the pot from Crate?

[Gtr_tech]

that part number means nothing to anyone but crate so it dosent really help me

Its a CTS part number. 270 series. http://www.ctscorp.com/components/potentiometers.htm
"Build" the correct part with the table at the last page....that gets you an off the shelf part #.

[Enzo]

Earth, Mark suggested you try getting it from Crate, and I provided the part number for it, so if that number means something only to Crate, well, isn't that who would want to know?

I've never seen those on anyone else's shelf, most of those roll your own numbers are for OEM custom ordering, but if someone stocks them generically, there is your alternate source.

[Steve Conner]

I'd also recommend you contact Crate's service department and ask them to sell you a replacement pot. Then you know it will just drop right in with no mods required, and the original knob will fit on it. If you just bought a generic 10k audio taper pot from Radio Shack, you might need to kludge things.

The last time I did this, I was fixing an Alesis synth that got one of its knobs snapped off. They were custom 360' dual gang pots that couldn't be bought off the shelf. I just found the UK office for Numark/Alesis, contacted them by e-mail, and they sent me the replacement part in no time at all. It's nice when manufacturers stand by their product

I think the roll your own numbers are for made to order batches, too. You go to CTS with the number and they make you a batch. They don't keep all the possible permutations in stock.