hey all,

im looking for a new integrated amp for my 2ch system. im starting to narrow down my my options, and a few brands ive been looking at are Rotel, Cambridge Audio, Parasound, and possibly Emotiva.

however, another brand that caught my eye is PS Audio. it seems like their "trio" series shows up on Audiogon somewhat frequently, and you can find them for a pretty good discount. but there is something i was curious about...

on the front, there is input selection, and a 'gain' knob. what is the difference between gain and volume? or is there any?

any and all advice/information is appreciated

thanks! :)

No practical difference.

Just another name for the same thing.

cool. thanks guys! that being said, does anyone have any quick feedback on the PS Audio products? i know thats more 2ch, but i figured while i had your attention

Don't know the current PS, but I loved the older stuff. They had an absolutely wonderful preamp in the 80's. I doubt they have gone down. Other brands, don't know their current products, are Parasound and NAD

http://www.psaudio.com/ps/products/description/trio-c-100?cat=audio

Just checked. NAD C720BEE has in/out. Somewhere around six hundred bucks. Next is a decent small crossover. Never found one, but DIY with a board from ESP is a viable option. ( I would not say my $10 mail order special is the hot tip). Using a full rack size 1U chassis works, but is not eloquent.

on the front, there is input selection, and a 'gain' knob. what is the difference between gain and volume? or is there any?

No practical difference.
Right.
Just another name for the same thing.
Nope.

Volume describes how great the output is. It can be varied with a volume control. OTOH, gain describes how much greater the output is compared with the input.

However, most volume controls do not change the actual gain of the device they work in. Instead, they reduce the magnitude of the input signal and, since the gain is fixed, reduce the output. So, effectively, they seem similar and, for general use, they are.

Very few volume controls are really gain controls, even if they are labeled as such.

Volume describes how great the output is.

My output is always great. :D:eek:

My output is always great. :D:eek:Yeah, I know. Now, where is that volume control? :D

Yeah, I know. Now, where is that volume control? :D

Ow. Ow. Ow. (Mute)

But does it go to eleven?

Kal is correct. Another issue is the use of the term volume control for wall- mounted, tapped transformers and L-pads. Technically they are attenuators meaning that they reduce the power delivered to a speaker from the amp.

Professional mix boards have BOTH gain controls AND volume controls. The gain controls (also called trims) set the ratio of the input to the output of the first stage of the mixer. (basically, the input sensitivity). The volume control (slide pots usually) control the signal delivered from the output of the first stage to the input of the second stage of the mixer. This is also the point at which effects are added and also in home stereo equipment of old where the tape monitor loops were located in the circuit.

My Fender guitar amps have both volume and gain controls as well as my effects pedals.

Nope.

Volume describes how great the output is. It can be varied with a volume control. OTOH, gain describes how much greater the output is compared with the input.

However, most volume controls do not change the actual gain of the device they work in. Instead, they reduce the magnitude of the input signal and, since the gain is fixed, reduce the output. So, effectively, they seem similar and, for general use, they are.

Very few volume controls are really gain controls, even if they are labeled as such.

I know, I started to write a whole paragraph about the differences and the different methods of controlling volume, but I figured since they are accomplishing the same thing, at least here, I would save it. I didn't see the need to confuse anybody.

I know that some volume controls are nothing more than limiting potentiometers while a gain actually varies the input level. But again, they accomplish the same thing. ;)

I know that some volume controls are nothing more than limiting potentiometers while a gain actually varies the input level.

You just said the same thing.
A volume control is typically a potentiometer wires as a voltage divider on the input signal.
A gain control is typically in the feedback path of the power amp, it adjusts the amount of amplification, AKA Gain.

Ok. They both somehow vary the volume. I don't know how they work. It's one of life's little mysteries. :D

Sorry to the EEs out there. ;)

No mystery here. If you have ONE control it can be labeled gain or volume. If you have two, one will be gain and the other volume as explained.

Okay, so in my garage I have a nice little Carver set-up consisting of a CT-17 preamp/tuner and a TFM 15CB amplifier. The preamp has the customary volume control while the amplifier has individual gain controls for each channel. How do the gain controls work?

How do the gain controls work?

Post the schematic and we'll tell you.

Well giz ought to be able to tell me without any schematics. He seems to act like he knows all since the difference between gain and volume is so apparent to him.

Besides, Kal said that volume varies the output, while gain controls the difference between input and output. Seems like a fairly straight forward task for someone with an electronics background, which I don't have.

In car audio, you set an amp's gain control to provide the highest level you would want if you cranked the volume control of the headunit to full. I imagine that preamp/amp is a similar situation.

Well giz ought to be able to tell me without any schematics. He seems to act like he knows all since the difference between gain and volume is so apparent to him.

Besides, Kal said that volume varies the output, while gain controls the difference between input and output. Seems like a fairly straight forward task for someone with an electronics background, which I don't have.Nope. The effect on the output is almost the same. One can distinguish them only with a schematic and/or with measurements.

BTW I service and design sound systems and have for 40+ years.

As I mentioned, if there is a single control it MAY be called gain or volume but this is a misnomer.

The gain or trim control in professional audio equipment controls basically the sensitivity of a given input to the first stage preamp. If you look at a performer on stage using a microphone, some will be holding the mic at a distance of about 6 inches from the mouth and some will be eating the mic. The engineer will adjust the trim(gain) on that particular mic to a higher or lower setting in order to avoid overloading the first stage input. Think of this as clipping on the first stage. If the gain is set too high, the first stage input is saturated and distortion is the result.

Most stage mics are dynamic and produce an average voltage of about 50 millivolts. The louder a sound presented on the diaphragm, the higher the voltage. The higher the voltage, the easier it is to saturate the input stage. The trim(gain) control is used to dial back the amplification created by the first stage.

We can adjust the gain on a preamp to compensate for someone speaking softly or at a greater distance from the mic. This creates a lower voltage from the mic presented to the first stage input. This is also true with source material and various playback devices. Some have hotter outputs than others and as such, need the gain reduced to the next input stage.

As I said earlier, the actual volume control is wired between the first and second stages of the preamp/amp combination. The volume control allows an increase in the ratio or the amplification AVAILABLE from the first stage to the second stage.

Less expensive or complicated systems have a single volume control but the gain is fixed by a set value resistor in the circuit as opposed to a pot or variable control. The function is always there in the circuit, there are no exceptions. It's just that some devices do not provide the user with a direct access to the gain setting.

In most AVR equipment, the CD, tape, DVD etc gains are set in a fixed circuit design in the first stage of the preamp. After the preamp stages, the source selector follows, then the volume control. The second and third stages also have preset gain controls to avoid saturation. This is a fact of amplifier circuit design. The volume control only controls how much of a preamped signal is fed to the next stage but the max gain in each stage is preset in the design of the circuit.

Nope. The effect on the output is almost the same. One can distinguish them only with a schematic and/or with measurements.

What would/could the differences be that would show up in a schematic?
BTW I service and design sound systems and have for 40+ years.

As I mentioned, if there is a single control it MAY be called gain or volume but this is a misnomer.

The gain or trim control in professional audio equipment controls basically the sensitivity of a given input to the first stage preamp. If you look at a performer on stage using a microphone, some will be holding the mic at a distance of about 6 inches from the mouth and some will be eating the mic. The engineer will adjust the trim(gain) on that particular mic to a higher or lower setting in order to avoid overloading the first stage input. Think of this as clipping on the first stage. If the gain is set too high, the first stage input is saturated and distortion is the result.

Most stage mics are dynamic and produce an average voltage of about 50 millivolts. The louder a sound presented on the diaphragm, the higher the voltage. The higher the voltage, the easier it is to saturate the input stage. The trim(gain) control is used to dial back the amplification created by the first stage.

We can adjust the gain on a preamp to compensate for someone speaking softly or at a greater distance from the mic. This creates a lower voltage from the mic presented to the first stage input. This is also true with source material and various playback devices. Some have hotter outputs than others and as such, need the gain reduced to the next input stage.

As I said earlier, the actual volume control is wired between the first and second stages of the preamp/amp combination. The volume control allows an increase in the ratio or the amplification AVAILABLE from the first stage to the second stage.

Less expensive or complicated systems have a single volume control but the gain is fixed by a set value resistor in the circuit as opposed to a pot or variable control. The function is always there in the circuit, there are no exceptions. It's just that some devices do not provide the user with a direct access to the gain setting.

In most AVR equipment, the CD, tape, DVD etc gains are set in a fixed circuit design in the first stage of the preamp. After the preamp stages, the source selector follows, then the volume control. The second and third stages also have preset gain controls to avoid saturation. This is a fact of amplifier circuit design. The volume control only controls how much of a preamped signal is fed to the next stage but the max gain in each stage is preset in the design of the circuit.

You are talking about gain as a stage of a preamp. As I said before I have a separate amplifier that has knobs labeled gain. I assume this is the same thing as car audio amplifiers that have adjustment pots labeled "sensitivity". How do they work?

What would/could the differences be that would show up in a schematic?

One is set up as a voltage divider, the other is a variable resistance in the feedback loop.

How do they work?


Post the schematic.

What would/could the differences be that would show up in a schematic?


You are talking about gain as a stage of a preamp. As I said before I have a separate amplifier that has knobs labeled gain. I assume this is the same thing as car audio amplifiers that have adjustment pots labeled "sensitivity". How do they work?

Your power amplifier has an input stage that as described admittedly sounds much like a preamp. That's what folks are talking about here, as I understand it, not a separate preamp.

Your power amplifier has an input stage that as described admittedly sounds much like a preamp. That's what folks are talking about here, as I understand it, not a separate preamp.

I know I thread jacked a little bit. :o

Duvetyne, I'm not curious enough to go out and find a schematic, or willing to pay for one, so I'll just keep wondering. ;)