Stepped Attenuator vs Log Pot

[SanjeevM]

If one uses a stepped attenuator in the place of a normal logarithmic potentiometer for controlling volume, is there an advantage, or is it just fashionable ?

 

[amangujral06]

a stepped attenuator is supposed to provide better resistance matching to both the stereo channels throughout the amplifier life. That being said, even a high quality logarithmic potentiometer with some age on it, say 10 years old amps, develop some oxidation and change in individual channel resistance for stereo channels.

I personally experience this degradation with my old amplifiers and the volume varies (power output in individual channel) when turniing volume knob and measured having logarithmic potentiometer .

 

[jls001]

Just like regular pots, stepped attenuators could either be logarithmic or linear.

I currently use two stepped attenuators of 10K log. I'm not happy with either

 

[Nikhil]

If one uses a stepped attenuator in the place of a normal logarithmic potentiometer for controlling volume, is there an advantage, or is it just fashionable ?

A lot depends on the quality of the resistors used. Which also makes them pretty expensive.
But there are a lot of options available online these days. I have DACT (Denmark) in my preamp.
If you have a high quality amp then definitely consider it.

I also have switched in the ALPS Blue Velvet potentiometer.
The sound is very comparable but there are differences in nuance.
Slightly thinner sounding but really only noticeable when you compare side by side.
Prices are much more reasonable and for that reason alone a very good option.

But this is info from my setup and I have no idea how this translates to another amp etc

Regards.


.

 

[SanjeevM]

Thats peculiar. If the max resistance of both attenuator and pot is the same, how can the type of control, i.e. pot/attn have any effect on the sound. If the load on the previous stage changes due to resistance, then SQ may change....

 

[keith_correa]

Thats peculiar. If the max resistance of both attenuator and pot is the same, how can the type of control, i.e. pot/attn have any effect on the sound. If the load on the previous stage changes due to resistance, then SQ may change....

Have you experienced a SQ change by using different brands/types of resistors & capacitors - values remaining the same? If yes, the same applies here too.

 

[SanjeevM]

I understand, SQ can change if value of the resistor is different, or there are inductance effects like in wirewound resistors. Are there any other reasons....

 

[SanjeevM]

Just like regular pots, stepped attenuators could either be logarithmic or linear.

I currently use two stepped attenuators of 10K log. I'm not happy with either

The attenuators are not cheap either!

I am trying to choose between volume control by software vs hardware. At present the Volumio software controls Rpi-DAC output, so I dont have a vol control on the Amp side.

If I attach my turntable to the Amp, then I will need a VC between the two. So I am thinking whether to invest in an Attenuator or to just buy a 10k log pot from Mouser india ....

 

[SanjeevM]

If I attach the VC, then I can set the Volumio volune to full and use the pot/Atn to control volume. I also wonder if sonically this will be better...