Volume control vs. attenuation control

In your case you're describing gain control vs. attenuation control on your preamp section that should be set to the best possible volume range that you want to operate your volume control for ex 7...12 o'clock. If you feel that you get distortions on the most of your listening range try to adjust one way or the other untill you get the most of sound and leave the gain control untouched.

I would try the combination you like, then do some critical listening. A/B between that and their suggested setting, and see if you loose/gain anything. If it sounds the same (better possibly?), go for it.

I would adjust the amp in so that I could turn the pre up to about 3:00or 0db for normal use as they say.

Can someone please explain the difference between a volume control on an amp and an attenuation control on a pre amp.

You start with a very small voltage signal from a source like phono cartridge and follow that with a series of amplifiers that make the voltage bigger. Typically some voltage gain stages in the phono section, more in the preamp, and more in the power amp. The gain of these amps is fixed. To control the volume you insert at least one voltage divider in the path to control how much gets through.

Attenuator sounds more impressive than volume control but they are exactly the same thing. They are voltage dividers that reduce (attenuate) the voltage to the level you want. It could be at the output of the source, input or output of the pre, or input of the amp, basically anywhere in the signal path, or you can have one in all of those places. Whoever made your stuff decided to call the one in the preamp an attenuator.

Technically an 'attenuator' cuts the signal before any amplification stages.

No, attenuate means to reduce, it doesn't matter where you do it. If it reduces the amplitude of the signal it is an attenuator no matter whether it is before or after the gain stage.

Anything that attenuates the signal also reduces the volume so therefore they are the same thing.

A volume control actually changes the active amplification of the signal, from well below less than what it comes in as, to increasing it.

That would be extremely unusual. As stated above, the gain of almost all active stages is fixed. The volume control is merely dividing the voltage so you get the level you want. It isn't possible for a typical volume control to increase the amplification of the signal.

Let's say you had a preamp stage with a gain of 10 which means if you put 1 volt in and turn it all the way up you would get 10 volts out. If you wanted only 2 volts out you would have to turn the volume control so it was a 5:1 voltage divider.

1 times 10 divided by 5 = 2

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03-14-11: Herman
Elizabeth wrote:
"Technically an 'attenuator' cuts the signal before any amplification stages."

No, attenuate means to reduce, it doesn't matter where you do it. If it reduces the amplitude of the signal it is an attenuator no matter whether it is before or after the gain stage.

as a practical matter, when it comes to the way that preamplifiers actually work, elizabeth is correct. the way that preamplifiers actually work is that they are designed to a set input sensitivity level. however, some sources might be higher or lower than that input sensitivity level. sources that are higher are "hot" sources, so when you switch to a "hot" source, your volume setting may become too high. if the source is really hot you may have to turn the volume down really low. what an attenuator does is to allow you to better control for differing voltage levels from differing sources by applying differing levels of signal reduction at the input. any gain would then occur within the preamplifier from that point.

03-14-11: Herman
Elizabeth wrote:
"A volume control actually changes the active amplification of the signal, from well below less than what it comes in as, to increasing it."

That would be extremely unusual. As stated above, the gain of almost all active stages is fixed. The volume control is merely dividing the voltage so you get the level you want. It isn't possible for a typical volume control to increase the amplification of the signal.

your explanation is incorrect. gain is determined by the ratio of input signal amplitude to output signal amplitude. the output signal amplitude from the preamplifier varies in response to the volume setting of the preamplifier. therefore, the gain from the preamplifier does indeed vary as elizabeth suggested.

as an aside, i will add that it is incorrect to say that an attenuator and a volume control are the same thing, because they aren't. depending upon the volume control setting you do often get gain as a result of the volume control (i will let others add comments specific to passive preamplifiers as i am not addressing that device in my comments) but you, of course, never get gain from an attenuator. and, as i stated above, it is also incorrect to say that the gain of a preamplifier is fixed: the reason why people use preamplifiers is to get variably controllable gain.