Thoughts on replacing slope resistor with a pot.

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ChrisM
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Re: Thoughts on replacing slope resistor with a pot.

Post by ChrisM »

briane wrote:for a personal amp its a fine idea. If its going on the road, in general less knobs is better. More knobs, more things for a tech to fiddle with, more things to go wrong.

One also has to wonder about the quality of the resistive material if you put a pot in there. Will you be getting RN65 smoothness and quitetude? We can surmise the answer is no.
That was my first thought.

Most posts are <0.5W carbon comp.
gar13
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Re: Thoughts on replacing slope resistor with a pot.

Post by gar13 »

A solution for removing DC from the pot was posted over on the Hoffman site:

http://www.el34world.com/Forum/index.php?topic=7337.0

I haven't tried it, or know if there is a way to adapt it for your OTS.

Dave
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Bob-I
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Re: Thoughts on replacing slope resistor with a pot.

Post by Bob-I »

briane wrote:One also has to wonder about the quality of the resistive material if you put a pot in there. Will you be getting RN65 smoothness and quitetude? We can surmise the answer is no.

in general there's no advantage to an RN65 on the slope. I've done RN65 vs. carbone comp and carbon film and they all sound pretty much the same. Different values on the slope though sound pretty dramatic.
JD0x0
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Re: Thoughts on replacing slope resistor with a pot.

Post by JD0x0 »

Hmm I think i'm going to try it with a PEC Pot which is rated at 2w and over 500V. And pray everything goes well
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briane
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Re: Thoughts on replacing slope resistor with a pot.

Post by briane »

in general there's no advantage to an RN65 on the slope. I've done RN65 vs. carbone comp and carbon film and they all sound pretty much the same. Different values on the slope though sound pretty dramatic.
Your right bob, its very subtle, and I also use CF in there depending on the application. Still in general I dont think a pot sounds as good as CF or MF.

And yes, changing the value of the slope is dramatic. I would think the best method here to use the pot to find the value, then replace with a resistor.

I have not tried the PEC or higher grade pots. I suspect one would experience a dramatic improvement over alpha's in the slope.
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heisthl
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Re: Thoughts on replacing slope resistor with a pot.

Post by heisthl »

Might as well just get a resistor decade box rather than mess with a pot, it's good for a lot of other trial and error type things too. Although on a gig it might look a little weird having clip leads coming out of your amp chassis :lol:
Former owner of Music Mechanix
www.RedPlateAmps.com
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