OK, experts... Please tell me what gain is. I've been playing for almost 50 years and have no clue...

[bukowski]

Very generally speaking and a simplified but adequate way to look at it in the context of modern guitar amps and pedals:

Gain (or pre gain) is distortion. It exists in the preamp section of the amp. Because of how it works it also increases overall volume.

Volume (or post gain) makes things louder, generally without adding much distortion. With that said, you can turn the volume knob up enough to drive the power tubes enough that they start clipping (distorting) a bit. For tube amps, if the volume is turned up enough that the power section is significantly distorted, it will be very loud. Think Marshall Plexi.

Again this is vastly simplified but it’s a pretty solid way to start.

Thanks, this is the way I viewed it before the post. Maybe I'm digging too deep and need to just forget it and get back to playing... I can stick with your explanation and just move on.

I blame Mesa Boogie for messing with my head ! Multiple drive knobs and multiple volume knobs... It gets complicated fast... Too many variables and way too many combinations.... Maybe I'll pull my Deluxe reverb out to take a break from Mesa...(although I love the Lonestar)--

 

[unix-guy]

There's a really good post by Cliff (@FractalAudio) - the creator of the Axe Fx - on the Fractal Audio Forum.

Understanding All the Different Gain Controls

The amp block in the Axe-Fx has a variety of gain controls that change depending upon the amp model selected. These controls are: Input Drive Input Trim Overdrive Master Volume These various controls are located at fixed points in the virtual amplifier circuit as follows: Input...

forum.fractalaudio.com

Ignore the part about Input Trim (because that doesn't exist on a real amp) and this pretty much answers your questions as they pertain to Amps.

In general, knobs labeled Drive or Gain are adding some amount of "intentional" distortion and also (usually) some volume.

 

[Frodebro]

So, boost is signal strength... If I take my Diamond Compressor and crank the volume, in effect that is gain? Yes, the definitions are killing me... Its different on all of my amps !

Please note: The Lonestar is by far the most confusing... All my other amps have "definitions" I can understand much more clearly. Example, my Deluxe Reverb. It has a volume control and tone controls. Nice and simple...

A boost increases the signal strength, which means it adds gain to the signal. This doesn't automatically mean it adds distortion (though in guitar amps that tends to be the net result).

Let's break this down to the fundamentals...

Suppose you have a straight guitar signal, we'll say for simplicity that it's 10mV. If you run it into a straight (clean) boost pedal, the pedal will increase that signal as the level on the pedal is increased. We'll say that maxed out it doubles the signal to 20mV. What it did was increase the gain of that guitar signal, but added no coloration or distortion. It simply took the existing signal and made it louder. This is the textbook definition of increasing the gain of the signal.

Now, how that relates to distortion in a tube amp involves the headroom of the input stage of the amps preamp. If you have gobs of headroom (think Twin Reverb), the sound will mostly get louder, but as the first preamp tube runs out of headroom, distortion and compression will gradually be introduced at that first input stage.

If you're running into an amp designed to get dirty (say a Marshall), hitting that input with a hotter signal will introduce distortion and compression much quicker, because that is what the amp is designed to do. Same guitar, same boost pedal, two different results.

 

[JasonE]

This subject can get deep real fast. In the simplest way think of them as cascading volumes. If you turn the gain up and leave the volume down, you will get distortion. If you turn them both all the way down then turn the volume all the way up then start turning the gain up, you will get a louder clean sound. This is a very simple way of looking at it but there are a lot of other factors involved in both amps and pedals. You start running components out of headroom and you start getting clipping which creates distortion. Gain is essentially volume.

You have this on mixers as well. You set the input gain on the channels to feed them the proper amount of signal. You can feed them too much and cause clipping which then distorts the sound of that channel. It can get really complicated when you introduce outboard gear to it. Then you have multiple gain stages to manage.

 

[Alex Kenivel]

Most things you plug audio into...
amps, interfaces, pedals, mixers,
All have a point (clipping threshold) at which excessive volume (too much gain) will distort (clip) the outcoming audio. In some cases it can be pleasing, in some cases not.

 

[Piing]

A picture is worth a thousand words

 

[[Nathan]]

Gain breaks shit
Volume/Level raises shit

 

[HotRats]

Gain and volume are just terms used (sometimes) Interchangeably in the context of guitar gear, they both refer to a knob that controls the amount of signal that is sent to the next stage (being it part of the internal circuit of an amp or what comes next in a pedalboard/rig)

But generally speaking:
- gain is used when increasing it you get more distortion form the circuit itself. As other have said, is mostly pre-gain
- volume is used when the main purpose of the control is to increase volume without much distortion form the circuit itself.

In this context, a clean boost pedal control is named volume because it doesn't distort itself (it might push what comes next into distortion but the pedal itself do not distort) while the input of a modern amp (or of a distortion pedal) is named gain because is what control the amount of distortion (clean channels might do not distort, though) and the signal coming out of that section of the circuit (or pedal) and going to the next will be distorted.

 

[Ed DeGenaro]

I get that anything, even solid state will distort when pushed to certain limits.... Not worrying so much about "clipping" now. I'm just trying to understand what gain is. Thank you for the explanation though, this explains why "gain" on the DOD 250 is more of a clipping knob...I'm with you (a bit)

But I'm seriously confused...

Gain seems to me to be a boost at the pre amp? I thought all volume was set by the pre amp? At least thats how it works with Audio gear, you have a pre amp (volume) and a power amp... There is no volume on a power amp in High End Audio... Its all taken care of by the pre amp.

So, I'm confused. Is there a volume knob on the pre amp (gain) and another volume increase somewhere at the power amp?

I need to take a basic electronics course---maybe build my own tube amp to learn from. I'm just a guitarist, not an electronics prefessional..(thats for sure!)

(thinking, while posting this)---- Boosting my Diamond compressor volume is pre boosting the pre amp? Pre- pre?

Gain literally is the multiplication (increase) factor of the input signal (going into a particular gain stage).
Literally what the name implies

 

[DISTORT6]

Gain breaks shit
Volume/Level raises shit

I want to tattoo this on my arm

 

[laxu]

I watch these guys all the time, never thought to look into boosts... I see many video's there covering this topic. I know too well these guys go into super detail, sometimes an hour long .... Great tip, thank you.

I've even considered the D&M drive, it has a pedal combination I know I would love. I just can't get over how ugly the pedal is... Orange with cartoon faces of Dave and Mic... I know pedal appearance means little but....

Maybe I can paint it.. (note two gain knobs !)

View attachment 55337

There is a limited edition "label maker" model of the pedal. Though IMO it's really ugly.

D&M Drive - Custom Shop Label Maker Edition - Keeley Electronics Guitar Effects Pedals

Limited, Custom Shop 'Label Maker' Edition High Voltage Boost Saturated Multistage Gain Advanced Switching for Pros Begins Shipping 10-22-2020

robertkeeley.com

My suggestion is that if you like the D&M Drive (and it's a nice pedal, I used to own one) then you just slap some stickers over Mick and Dan. The orange color is IMO nice in person.

 

[Frodebro]

Gain breaks shit
Volume/Level raises shit

Gain and volume are basically the same thing. Increasing the amplitude of the input signal. Before the preamp, the preamp itself, or the power amp, it’s all gain increases.

Note how the term “gain staging” is used in signal chains, particularly recording situations. That means optimizing volume levels from one component to the next, one effect to the next, etc. it has nothing to do with distortion.

 

[Sascha Franck]

Gain (or pre gain) is distortion. It exists in the preamp section of the amp. Because of how it works it also increases overall volume.

Volume (or post gain) makes things louder, generally without adding much distortion.

This is really all you need to know for a start, regardless of the different amplification topologies and usage of words.

Gain breaks shit
Volume/Level raises shit

And that is another way to explain it.

A picture is worth a thousand words

View attachment 55348

And that pretty much nails it, too, but I'd possibly add something, following Nathan:

Also I'd like to add that pretty often "gain" and "drive" are used interchangeably.

 

[Jarick]

I always think of it like this:

There's an amplification stage that's fixed, it may make your signal 10 times louder while staying clean or it may stay the same volume while getting really distorted.

Gain adjusts the signal going into the amplifier.

Level adjusts the signal coming out of the amplifier.

 

[bukowski]

There's a really good post by Cliff (@FractalAudio) - the creator of the Axe Fx - on the Fractal Audio Forum.

Understanding All the Different Gain Controls

The amp block in the Axe-Fx has a variety of gain controls that change depending upon the amp model selected. These controls are: Input Drive Input Trim Overdrive Master Volume These various controls are located at fixed points in the virtual amplifier circuit as follows: Input...

forum.fractalaudio.com

Ignore the part about Input Trim (because that doesn't exist on a real amp) and this pretty much answers your questions as they pertain to Amps.

In general, knobs labeled Drive or Gain are adding some amount of "intentional" distortion and also (usually) some volume.

Thanks, but this is exactly why I'm asking. My Mesa has a Gain knob AND a drive knob...

All good though, I understand what your saying..

 

[Sascha Franck]

Thanks, but this is exactly why I'm asking. My Mesa has a Gain knob AND a drive knob...

I have no idea about the exact topology, but I think it's very likely (make that pretty much certainly) that the two are sitting in different positions of the signal chain. Both of them will affect the amount of "dirt", but the outcome will be sonically different. I think "gain" will raise the entire input level whereas "drive" is located later in the chain (on some Mesas it's even sitting behind the some tone controls, so the character of the drive will also be affected by the tone control).

 

[bukowski]

There's a really good post by Cliff (@FractalAudio) - the creator of the Axe Fx - on the Fractal Audio Forum.

Understanding All the Different Gain Controls

The amp block in the Axe-Fx has a variety of gain controls that change depending upon the amp model selected. These controls are: Input Drive Input Trim Overdrive Master Volume These various controls are located at fixed points in the virtual amplifier circuit as follows: Input...

forum.fractalaudio.com

Ignore the part about Input Trim (because that doesn't exist on a real amp) and this pretty much answers your questions as they pertain to Amps.

In general, knobs labeled Drive or Gain are adding some amount of "intentional" distortion and also (usually) some volume.

Thanks, I'm reading this now. This diagram is how I imagined it worked...

I think I've got enough here to move on... For now, I'll just consider "Gain" to be a tone shaping tool or another form of overdrive or a boost.

 

[bukowski]

I have no idea about the exact topology, but I think it's very likely (make that pretty much certainly) that the two are sitting in different positions of the signal chain. Both of them will affect the amount of "dirt", but the outcome will be sonically different. I think "gain" will raise the entire input level whereas "drive" is located later in the chain (on some Mesas it's even sitting behind the some tone controls, so the character of the drive will also be affected by the tone control).

No worries , I appreciate the explanation. The reason I've never asked this question in 40 years is because in most cases "gain" has translated to overdrive/distortion/clipping to me... That's why I included a picture of a DOD overdrive and my amp...

What had me scratching my head is the gain AND a Drive knob.... Note, on channel 1 (clean channel) the gain produces very little over drive even when cranked..

 

[dbagchee]

From the Lonestar manual:

“Switching in the DRIVE control adds 2 more triode stages and an additional gain control to meter in the exact blend of smooth singing saturation.”

So yeah just another name for the same thing. Knowing the amp (or pedal) involved makes a big difference.

In the Mesa Marks, the Treble also acts as a gain control!

 

[bukowski]

A boost increases the signal strength, which means it adds gain to the signal. This doesn't automatically mean it adds distortion (though in guitar amps that tends to be the net result).

Let's break this down to the fundamentals...

Suppose you have a straight guitar signal, we'll say for simplicity that it's 10mV. If you run it into a straight (clean) boost pedal, the pedal will increase that signal as the level on the pedal is increased. We'll say that maxed out it doubles the signal to 20mV. What it did was increase the gain of that guitar signal, but added no coloration or distortion. It simply took the existing signal and made it louder. This is the textbook definition of increasing the gain of the signal.

Now, how that relates to distortion in a tube amp involves the headroom of the input stage of the amps preamp. If you have gobs of headroom (think Twin Reverb), the sound will mostly get louder, but as the first preamp tube runs out of headroom, distortion and compression will gradually be introduced at that first input stage.

If you're running into an amp designed to get dirty (say a Marshall), hitting that input with a hotter signal will introduce distortion and compression much quicker, because that is what the amp is designed to do. Same guitar, same boost pedal, two different results.

OK, I'm with everyone here. I get it, thanks so much for all the great explanations....

Its mainly the usage of a gain knob on my Lonestar that got me thinking...Its all Mesa's fault !

The gain knob on my Mesa acts like a volume control, and a dramatic tone shifter. Most amps I've played have a gain knob that acts like a distortion pedal. This is not the case at all with the gain knob on the Lonestar... In fact, gain cranked on channel 1 is still clean.. And yes there is a drive knob too...I won't bother to ask what this does !