All choked up

Prev Next

There's an interesting misunderstanding about attenuators I thought I might address today: they "choke" the sound. That ain't necessarily so. I have been wondering where that thought process came from and it occurs to me it just might be closer to home than imagined. It might be me! Ok, so I've mentioned in a few posts how every analog volume control has a sweet spot, usually above 75%. I have also made the analogy that a volume control is like a brake in a car, the less you use the better it will run. I used these analogies to illustrate a point that turning the volume on a preamp up is not "stressing" or "pushing" anything, as you might by flooring the gas on your car. Rather, it's like removing your foot from the brake. Ergo, attenuators "choke" the sound and less is better. Makes sense. Only, it's not necessarily true. Here's a quick explanation. It really depends on how you're attenuating the signal, not the act of attenuating. In an analog volume control, which is a simple resistive element with a sliding contact point, the more attenuation you have the more resistance between the source and the amp. Bigger resistors in series generally don't sound as good as smaller ones. Simple. However, there is another type of attenuator, the simple resistive divider. There's one in the output of DirectStream. It is used to attenuate the output by 20dB in case you have sensitive loudspeakers. It's a feature I wish we had in the PWD. It is very simple, consisting of 2 resistors: one in series with the output and one dividing the signal to ground. The series resistor is always in the circuit. If you want to lower the DAC's gain, you add the "shunt" resistor to ground; thus taking away some of the output signal. This method does not choke the sound. Not ever. You lose nothing with it in or out. It just works and DirectStream sounds identical with the volume cut in or out. Sometimes using car analogies for audio, which is something I like to do, can be so simple as to be misleading.
Back to blog
Paul McGowan

Founder & CEO

Never miss a post


Related Posts

1 of 2