Taper on 35mm slide pot Prod.ID 4271?

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HowardP
 
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Taper on 35mm slide pot Prod.ID 4271?

Post by HowardP »

Hi,

The datasheet for product ID 4271 doesn't clearly, if at all, describe the taper for this product.

Anyone know if it's linear or audio?

thanks!
- HP in N.FL

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Franklin97355
 
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Re: Taper on 35mm slide pot Prod.ID 4271?

Post by Franklin97355 »

It is a 'B' taper according to the datasheet.
A pot can be used for volume or tone. The A or B refers to the taper, and people have different theories about which is best for volume or tone:
A = Audio Taper
B = Linear taper

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HowardP
 
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Re: Taper on 35mm slide pot Prod.ID 4271?

Post by HowardP »

Thanks for the prompt response, Franklin

Interesting - yes - I saw that on the 4271 datasheet you mention:

2 抵抗变化特性
Resistance taper □A ■B □C □D □W
(see) https://cdn-shop.adafruit.com/product-f ... C13404.pdf

but had long forgotten that A, B, C, D, W are standardized. For anyone who happens to venture into this thread, here's the taper skinny on some of them.
https://eepower.com/resistor-guide/resi ... ntiometer/

Understood about the audio vs linear discussions. Guess it really depends on the pot's function, underlying op amps / circuit. Linear tapers appear most frequently in the audio signal chain of recording studio mixing consoles. Whereas, seemingly counterintuitively, logarithmic (audio) ones are more common in simple audio circuits.

Here's an insight from Douglas Self, considered one of the worlds experts in audio engineering:
Because of their log/antilog operation, VCAs (Voltage Control Amplifiers) are characterized by an exponential control characteristic, so gain varies directly in decibels with [its] control voltage. This is extremely convenient, as it means that a linear fader {like the one mentioned in this thread} can be used to control gain over a wide range; however, this is in practice less than ideal, as it spreads out the less important higher and lower attenuation range too much. Special "VCA-law" faders are made that squeeze the high attenuation range so the normal operating range can be expanded.

--- pp. 689-690, Small Signal Audio Design, 3rd ed., Self, Doulas; Routledge, Focal Press, 2020, ISBN 978-0-367-46895-8

- H

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