Difference between overdrive pedal and gain dial on amp?

deefstes · 2011-05-26T10:24:50+00:00

OK, I realise you get all sorts of different overdrive pedals that give you all sorts of different flavours of overdrive (not that I really understand what t...

Difference between overdrive pedal and gain dial on amp?

Gearhead

In my opinion, too much gain in a preamp (of a tube amp) causes distortion of the real kind, and pedals try to mimic this effect. The fact that this is not the real thing has become less important over time and pedals are now considered to have their own 'flavour'. In essence the effect is the same: over a certain output voltage, the output of the gain stage or pedal does not linearily follow the input signal. If it does this abruptly you call it fuzz and if it does this gradually you call it distortion (regardless of the amount of it) or breakup.

ezietsman

Another thing to realise (and I think few people realise this) is that when you have valves doing to the distortion for you, you can make them overdrive/distort LESS if you turn your guitar's volume down, very few pedals manages this properly. Most valve amps will clean up almost completely, especially those without negative feedback (Vox AC 30s, Marshall 1974x etc)

deefstes

ezietsman wrote: Another thing to realise (and I think few people realise this) is that when you have valves doing to the distortion for you, you can make them overdrive/distort LESS if you turn your guitar's volume down, very few pedals manages this properly. Most valve amps will clean up almost completely, especially those without negative feedback (Vox AC 30s, Marshall 1974x etc)

I'm not sure I understand exactly what you mean. Are you saying that on most valve amps the sound you get with low volume and high gain could be almost the same as with low gain and high volume?

MikeM

ezietsman wrote: Most valve amps will clean up almost completely, especially those without negative feedback (Vox AC 30s, Marshall 1974x etc)

Negative feedback reduces THD. It was once explained to me as making the taper towards distortion (when cranking the gain) more logarithmic instead of linear.

Keira-WitherKay

deefstes wrote:
ezietsman wrote: Another thing to realise (and I think few people realise this) is that when you have valves doing to the distortion for you, you can make them overdrive/distort LESS if you turn your guitar's volume down, very few pedals manages this properly. Most valve amps will clean up almost completely, especially those without negative feedback (Vox AC 30s, Marshall 1974x etc)
I'm not sure I understand exactly what you mean. Are you saying that on most valve amps the sound you get with low volume and high gain could be almost the same as with low gain and high volume?

what he's saying is if you have your tube amp set so with the guitars volume knob open full you get doverdrive from the tubes....... if you leave the amp setting as is........ but just roll back some volume on your guitars volume knob ( not the volume on the amp ) and you can get less overdrive and even get the sound clean, ................. and most normal distortion /overdrive pedals pedals can't do that

ezietsman

deefstes wrote:
ezietsman wrote: Another thing to realise (and I think few people realise this) is that when you have valves doing to the distortion for you, you can make them overdrive/distort LESS if you turn your guitar's volume down, very few pedals manages this properly. Most valve amps will clean up almost completely, especially those without negative feedback (Vox AC 30s, Marshall 1974x etc)
I'm not sure I understand exactly what you mean. Are you saying that on most valve amps the sound you get with low volume and high gain could be almost the same as with low gain and high volume?

Well that is also almost true. Low Gain, high volume will result in your power tubes giving distortion but it will sound different to preamp distortion.

Keira explained my statement perfectly.

@MikeM, indeed, negative feedback reduces the distortion in an amp as well as make the transition from clean to overdrive more drastic, however, according to what I read online, amps without negative feedback are preferable for those who want to use their guitars' volume knobs to control the amount of overdrive.

deefstes

Keira WitherKay wrote:
deefstes wrote:
ezietsman wrote: Another thing to realise (and I think few people realise this) is that when you have valves doing to the distortion for you, you can make them overdrive/distort LESS if you turn your guitar's volume down, very few pedals manages this properly. Most valve amps will clean up almost completely, especially those without negative feedback (Vox AC 30s, Marshall 1974x etc)
I'm not sure I understand exactly what you mean. Are you saying that on most valve amps the sound you get with low volume and high gain could be almost the same as with low gain and high volume?
what he's saying is if you have your tube amp set so with the guitars volume knob open full you get doverdrive from the tubes....... if you leave the amp setting as is........ but just roll back some volume on your guitars volume knob ( not the volume on the amp ) and you can get less overdrive and even get the sound clean, ................. and most normal distortion /overdrive pedals pedals can't do that

Aha, thanks. Makes sense now.

MikeM

ezietsman wrote: @MikeM, indeed, negative feedback reduces the distortion in an amp as well as make the transition from clean to overdrive more drastic, however, according to what I read online, amps without negative feedback are preferable for those who want to use their guitars' volume knobs to control the amount of overdrive.

Because the overdrive has a more linear response ? They won't get as clean as easily as NFB amps will.

Gearhead

The gain button on most valve amps does almost the same as the volume button on your guitar: determine the amount of signal fed into the rest of the gain stages.
Negative feedback does not make the distortion more or less linear. It is usually applied to the phase inverter so it only affects the power amp distortion and not the preamp distortion (gain). It does makes the power amp distortion mure sudden since it tries to minimise the difference in signal shape between the preamp out / phase inverter in and the power out / speaker in.

MikeM

Then mind explaining exactly what it does Mr Gearhead? I just chimed in so folk don't get the wrong idea, but the matter is not completely clear to me either.

singemonkey

On a related point, while it's true that distortion boxes don't usually allow control of overdrive through the guitar volume knob (or pick attack) that's looking to soon be a thing of the past. An increasing number of pedals mimic the preamps of amplifiers (if I've got that right) and allow a response that's very similar to an amplifier. These will always have the word "dynamic" somewhere in the marketing literature.

deefstes

OK, but if all that's been said so far is correct, why do people bother buying overdrive pedals? I mean it seems that overdrive pedals are trying hard, and are succeeding only partially, to do what the gain and volume knobs on the amp do. So if the amp can do it better anyway, why pay good money for a pedal?

ActionArnie

deefstes wrote: OK, but if all that's been said so far is correct, why do people bother buying overdrive pedals? I mean it seems that overdrive pedals are trying hard, and are succeeding only partially, to do what the gain and volume knobs on the amp do. So if the amp can do it better anyway, why pay good money for a pedal?

1) Probably because pedals can give you a decent drive tone at lower volumes

2) Pedals allow you to get different drive tones that your valve amp may not have been able to give you. i.e. A Twin Reverb on its own is unlikely to ever sound like a JCM800, but there are pedals that'll give you a reasonable approximation of a JCM800 through a Twin Reverb

deefstes

ActionArnie wrote:
deefstes wrote: OK, but if all that's been said so far is correct, why do people bother buying overdrive pedals? I mean it seems that overdrive pedals are trying hard, and are succeeding only partially, to do what the gain and volume knobs on the amp do. So if the amp can do it better anyway, why pay good money for a pedal?
1) Probably because pedals can give you a decent drive tone at lower volumes

2) Pedals allow you to get different drive tones that your valve amp may not have been able to give you. i.e. A Twin Reverb on its own is unlikely to ever sound like a JCM800, but there are pedals that'll give you a reasonable approximation of a JCM800 through a Twin Reverb

Alright, makes sense, thanks.

Manfred-Klose

I use overdrive pedal infront of the drive channel to bring it out a bit.
not putting to much in the pedal to make it noisy and stuff. just some extra color in the signal.

how i setup up my overdrive pedal(depending for what application), boss ds-1, boss sd-1, tube screamer and some other few odd pedals:

turn the tone and gain on zero
the the volume all the way up.
now play with it and with out it, mildly start adjusting the gain and tone knob until you find something that sounds good.

Modern amps have way to much gain in them already so you dont really need anything in there.

overdrive pedals are cool with the jcm 800's jmp's old fender and other exceptions.

if you'll look at some classic rigs of famous guitar players form the past, you'll see that most of them have used or still use an overdrive pedal infront of their amps.

MikeM

If we're working on all out tone, pedals can take you further. Most people aim for a sweet spot on a tube amp, where if you dig in, you get some dirt, and if you roll back some volume it cleans up. From that point you can add an overdrive with a very low gain but high volume to get a natural tube overdrive and a slight colour/compression to the sound. That's my logic to it at least. Just increasing and decreasing the gain on an amp will keep you in the same tonal range, a pedal can broaden that.

Also pedals can take an amp into distortion further than it's capable of on it's own.. Hi-gain type. On my current amp I can actually get fuzz out of it using a TS9 ?

ezietsman

Pedals definitely gives you more tonal ground for less money. They are utterly useful, even amp drive snobs like me like them ?

BTW. Here's what I mean with cleaning up the drive of an amp with guitar controls. This guy is using his LP straight into the amp (Original '59 Burst and Original Trainwreck, but the same applies to most valve amps, some clean up as well as this and some don't). This is some of the best (if not THE best) tone I have heard.

Dingwall

ezietsman wrote: Pedals definitely gives you more tonal ground for less money. They are utterly useful, even amp drive snobs like me like them ?

BTW. Here's what I mean with cleaning up the drive of an amp with guitar controls. This guy is using his LP straight into the amp (Original '59 Burst and Original Trainwreck, but the same applies to most valve amps, some clean up as well as this and some don't). This is some of the best (if not THE best) tone I have heard.

Hey ezietsman - this is very weird. In the 80s when I was just learning guitar, Guitar Player mag in US used to give a free floppy vinyl with each mag for a while. Anyway I remember very clearly that one of these was a guitar competition with the winners songs on the vinyl. Well the guy that won was Glen Kuykendall and his playing blew me and my best friend away at the time. And over the years I have been trying to track it down but couldn't really remember who it was until I watched your vid and it all came rushing back to me! It was Glen K! Kind of strange hearing him play now after all these years! But I agree on the tone though. How many watts is that amp out of interest?

Re the topic - I bought a Cornford one channel amp and was very keen to explore the amp distortion rather than pedals, using my volume to clean up as necessary. I tried this for a few gigs, and in the studio when we did our demo, but I found it a little restrictive and limiting - especially in a covers band! So in the end I brought back the pedals. I mix the amp so that I get a good clean sound first, just breaking up, and then I use pedals for all gain. Problem is that I have about 5 pedals on my board capable of producing gain so where does it end!!

The main problem with using amp for gain was the cleans I was getting with the volume rolled down just did not cut through like a proper clean sound. So for me its better to have a good clean amp sound and then get the dirt from pedal-age! Remember the volume you play amp at though also plays a big part.

ezietsman

Dingwall wrote:
ezietsman wrote: Pedals definitely gives you more tonal ground for less money. They are utterly useful, even amp drive snobs like me like them ?

BTW. Here's what I mean with cleaning up the drive of an amp with guitar controls. This guy is using his LP straight into the amp (Original '59 Burst and Original Trainwreck, but the same applies to most valve amps, some clean up as well as this and some don't). This is some of the best (if not THE best) tone I have heard.

Hey ezietsman - this is very weird. In the 80s when I was just learning guitar, Guitar Player mag in US used to give a free floppy vinyl with each mag for a while. Anyway I remember very clearly that one of these was a guitar competition with the winners songs on the vinyl. Well the guy that won was Glen Kuykendall and his playing blew me and my best friend away at the time. And over the years I have been trying to track it down but couldn't really remember who it was until I watched your vid and it all came rushing back to me! It was Glen K! Kind of strange hearing him play now after all these years! But I agree on the tone though. How many watts is that amp out of interest?

Re the topic - I bought a Cornford one channel amp and was very keen to explore the amp distortion rather than pedals, using my volume to clean up as necessary. I tried this for a few gigs, and in the studio when we did our demo, but I found it a little restrictive and limiting - especially in a covers band! So in the end I brought back the pedals. I mix the amp so that I get a good clean sound first, just breaking up, and then I use pedals for all gain. Problem is that I have about 5 pedals on my board capable of producing gain so where does it end!!

The main problem with using amp for gain was the cleans I was getting with the volume rolled down just did not cut through like a proper clean sound. So for me its better to have a good clean amp sound and then get the dirt from pedal-age! Remember the volume you play amp at though also plays a big part.

That will be 100 Watts of awesome. And no, there's no attenuator or master volume on that amp. and Yes, he is wearing earplugs ?

AlanRatcliffe

Dingwall wrote: Guitar Player mag in US used to give a free floppy vinyl with each mag for a while.

'84 IIRC. The first three were Steve Vai's Attitude Song (he was transcribing the series, so they put him on first to establish his cred), Malmsteen's Black Star and Allan Holdsworth's Devil Take the Hindmost - first I'd heard each and I very nearly gave up playing...

Well the guy that won was Glen Kuykendall and his playing blew me and my best friend away at the time.

The track Legs Akimbo wasn't it? A very unusual and almost atonal piece.

The main problem with using amp for gain was the cleans I was getting with the volume rolled down just did not cut through like a proper clean sound.

You just need to add a decent treble bleed circuit to your guitar's volume control. ? Simple mod involving at most a small cap and resistor.