The Electric Piano Forum

General => The Wurlitzer Electric Piano => Topic started by: beginnersluke on May 27, 2019, 08:13:30 AM

Title: 200A potentiometer taper
Post by: beginnersluke on May 27, 2019, 08:13:30 AM
This seems like a thing that would be in the service manual, but I can't find it. I also couldn't find the answer on previous forum topic here.

What's the taper on the volume pot (linear or logarithmic/audio)?
What's the taper on the vibrato pot (linear or logarithmic/audio)?

I feel comfortable with my hypothesis that the volume uses an audio taper, but I'm less sure about the vibrato pot.

Thanks as always!

Luke
Title: Re: 200A potentiometer taper
Post by: beginnersluke on June 04, 2019, 07:27:11 AM
I measured the volume pot, and it definitely appears to be an audio/log taper.

That's been a really difficult pot to find with a good switch and in the proper size. As in, I basically haven't been able to find it.

I see that Retrolinear sells one, but I am genuinely curious if what they sell is the audio taper. Does anyone here know (or have one to measure)?

It says they use CTS pots (which are very good, and widely used on quality guitars), but it no one seems to have to correct pot with the audio taper. (The linear taper is easy to find.) (The CTS website has a very handy tool where you can look for even partial part numbers across their suppliers.)

The taper is just a matter of touch: either works just fine, it just affects how touchy the knob is.

(I already have a linear taper pot that would work for the vibrato, so I may as well try it and see how it feels. I'll have to measure a friends to see what the original is.)

Luke
Title: Re: 200A potentiometer taper
Post by: sean on June 04, 2019, 01:07:39 PM


Why would you think that RetroLinear would sell the wrong pot?  They know their stuff.  Get it from them, then you are done.

Furthermore, they have a telephone number and email - contact them directly.  They will get you the right parts.

Sean

Title: Re: 200A potentiometer taper
Post by: beginnersluke on June 04, 2019, 01:54:29 PM


Why would you think that RetroLinear would sell the wrong pot?


Sorry, that's certainly not what I meant to imply.  I personally wouldn't call it wrong anyway (that's what I meant by "The taper is just a matter of touch: either works just fine").

The reason I asked the question was because if it is a log (and I sort of suspect it is, tbh), I wonder how they got them. (A custom order directly from CTS perhaps?) That's just an interesting question to me. That's really all I was getting at.

Thanks,

Luke
Title: Re: 200A potentiometer taper
Post by: retro-mike on June 05, 2019, 03:13:25 PM
Our new production CTS Volume pots work with original Wurlitzer 200A and our EP200A Amplifiers
if you need one shoot me an email >>   mike@retrolinear.com   - we'll get ya situated ;)


Thanks.



Title: Re: 200A potentiometer taper
Post by: retro-mike on June 06, 2019, 02:16:05 PM
Almost forgot, our CTS Switched vol pot is 10K Audio taper.
Title: Re: 200A potentiometer taper
Post by: beginnersluke on June 07, 2019, 11:51:55 AM
Mike,

That's awesome. Yeah, that seems like a hard part to source. It's great that you have it! (Eventually I'm going to get one of your amps for this thing anyway! A friend of mine just got one installed in his 200A and it sounds great!)

Luke
Title: Re: 200A potentiometer taper
Post by: retro-mike on June 07, 2019, 01:34:49 PM
Good to hear!  Just so you know- we have our amp kits and replacement parts setup so if your purchasing an amp + additional parts like the varivib, knobs, pots, output board etc the add-on items are  discounted :)