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I plan to add two input attenuators to a Dynaco ST35. Since the chassis is so slim, I bough two mini Clarostat linear taper 250K pots. To get close to the desired 100K ideal attenuator value, I swamped each with a 250K resistor.

On my meter, the lowest resistance with full clockwise rotation of the pot is 1.5 ohms on one pot, 1.0 on the other. Doesn't look too good. Did I get the wrong type of pots? I was assuming that when I want full signal passing into the the amp, I should be getting close to 0, with both pots having almost the same reading?

Well you just have to wire them in correctly and they will be fine , use the wiper to the grid and the terminal that reads 1 ohm to the input connector , and the other terminal to ground . should have bought log pots ( audio taper )

Thanks. I come from the electric guitar world where a log pot in the volume position gives to drastic a volume change with just a slight rotation on the pot. That's why I got linear. Must be different in the hi-fi realm.

The minimum resistance of potentiometers can be from zero up to a few ohms, the minor differences in resistance isn't a problem.

/ed B

You can "fake" a log pot from a linear one, but you need to hang a resistor from wiper to ground that's 1/10 the pot's resistance. So to get a 100K "log" pot, you'd need a 1Meg linear and a 100K resistor.

Cheers!