MN Taper Pots

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Posted on July 31, 2023 at 19:12:14

Triode_Kingdom
Audiophile

Posts: 9896
Location: Central Texas
Joined: September 24, 2006

I'm building a preamp from scratch and have just stumbled across the MN taper pots at Antique Electronic Supply. These look perfect for a Balance control, better than the plain ALPS linear pots I had planned to use. Has anyone here used these in a stereo audio system? I'm mostly wondering how well the resistances of the front and rear sections are likely to match at the center setting, and whether these would qualify for use in a high-end design. I previously purchased ALPS 500k linear pots for this, but the action regarding rotation and attenuation isn't quite what I want.

Bourns 500K MN Taper

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Why not use a shunt style balance control?

Ralph

11:20:04 08/02/23

3

RE: Why not use a shunt style balance control?

Triode_Kingdom

21:30:04 08/02/23

2

You have to use a series resistance

Ralph

08:18:22 08/03/23

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Why not use a shunt style balance control?

Ralph

11:20:04 08/02/23

3

RE: Why not use a shunt style balance control?

Triode_Kingdom

21:30:04 08/02/23

2

You have to use a series resistance

Ralph

08:18:22 08/03/23

RE: You have to use a series resistance

Triode_Kingdom

11:34:49 08/03/23

They are very small and have a nice feel

Chip647

14:22:32 08/01/23

Have you used the Fender (Alpha) version?

Triode_Kingdom

19:29:14 08/01/23

RE: MN Taper Pots

6bq5

09:35:29 08/01/23

RE: MN Taper Pots

Story

06:42:34 08/01/23

RE: MN Taper Pots, posted on August 1, 2023 at 06:42:34
Story Audiophile Posts: 9314 Location: NJ Joined: December 11, 2000	those don't look like the Bourns pots I'm familiar with whatsoever, say 20-30 years go. They look small and imprecise, most likely not the same high quality company now so I can't say. The ALPS are not the same either. Good luck on the search

RE: MN Taper Pots, posted on August 1, 2023 at 09:35:29
6bq5 Audiophile Posts: 4209 Location: SF Bay Joined: August 16, 2001	They will certainly work- I have seen Bourns pots like this - and for $2.50 ea! worth trying! Happy Listening

They are very small and have a nice feel, posted on August 1, 2023 at 14:22:32
Chip647 Audiophile Posts: 2578 Location: The South Joined: December 24, 2012	I have used this pot in a stereo volume configuration and they work well. My problem with balance controls is that there is always a reason that something is not balanced that can be corrected in the system rather than using a balance pot. A 1-2-3dB resistor and switch is enough though. If you are more than 3dB out of balance there is a serious problem.

Have you used the Fender (Alpha) version?, posted on August 1, 2023 at 19:29:14

Triode_Kingdom
Audiophile

Posts: 9896
Location: Central Texas
Joined: September 24, 2006

AES sells a 250K MN taper made for Fender. I ran a simulation of both values, and there's very little difference in terms of loss or loading in my circuit. The Alpha looks like it might be a better quality component, and this brand has worked well for me in the past. I guess they're used to pan between pickups in Fender guitars.

EDIT: I agree with you about system balance. I really only use a balance control once in a while for testing.

Why not use a shunt style balance control? , posted on August 2, 2023 at 11:20:04
Ralph Manufacturer Posts: 4674 Location: Minnesota Joined: April 24, 2002	You'd only need a single pot if the circuit is single-ended, and you can use a linear taper.

RE: Why not use a shunt style balance control? , posted on August 2, 2023 at 21:30:04
Triode_Kingdom Audiophile Posts: 9896 Location: Central Texas Joined: September 24, 2006	Is that the configuration where the wiper is grounded? That's a good approach, but this is a preamp with a minimalist (passive) signal path up to the balance control. I'm concerned that the wiper would load down the signal path at the ends of rotation, possibly causing other issues. It's a good fallback though if the MN taper doesn't work as planned. I ordered a few pots today to evaluate.

You have to use a series resistance, posted on August 3, 2023 at 08:18:22
Ralph Manufacturer Posts: 4674 Location: Minnesota Joined: April 24, 2002	So the balance control doesn't load the source. But if you want to talk minimalist, its more so than using dual controls and has the advantage of an easy to find part and no noise whatsoever when its operated. A 1M linear taper control can work quite well- your series resistance for each channel then being about 50K or so. That won't load your source.

RE: You have to use a series resistance, posted on August 3, 2023 at 11:34:49

Triode_Kingdom
Audiophile

Posts: 9896
Location: Central Texas
Joined: September 24, 2006

Thanks for mentioning this. I think Fisher did that in a few models, probably other brands as well. In my preamp (under construction), a "Stereo-Rev-Mono" switch precedes the balance control. Each channel has a series resistor ahead of that switch in order to provide a "mix" in mono mode. I agree the shunt balance control would probably work well in this situation. The MN taper isn't necessarily more intrusive, assuming a very low resistance through the wiper when the control is centered. The pots I ordered are MN, and they have a center detent that I think will be a nice touch. I'll move to a 500K or 1M shunt if they don't work out for some reason.

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MN Taper Pots

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