Dialing in amp tone

[Joe]

I have seen several questions about obtaining that longed for “blues tone”. When trying to dial in a tone, it is essential to know your gear, and what is happening when you adjust various knobs and switches. In this post, I will attempt to cover the basics.

On any amp, there are three types of core settings you need to understand:
1. The volume controls, which may be called gain and master, volume and master volume, etc… whatever they are labeled, there is one on the left and one on the right. I will refer to them as gain and master.
2. The tone controls, typically bass middle and treble.
3. The reverb control.

The tone controls and reverb control are fairly straightforward, if you are unclear on their effect, adjust them one at a time from 1 to 10 and use your ears.

The setting that tends to cause the most confusion is the volume setting. A guitar amp’s circuitry is divided into two sections, the preamp and the power amp.

Key concept to keep in mind–
Put simply, the gain knob controls the preamp level, and the master controls the power amp level.

The preamp and power amp each have a limit to the level they can put out cleanly, after which they start to “clip”, that is, the signal will become distorted.

Since power amp clipping tends to take place at very high volume levels, I will focus mainly on preamp distortion.

Dialing in “edge of breakup” tone:

Start at a very low volume, perhaps 1 on both the gain and master volume. Your guitar tone should be very clean and bell-like at this level. (Some amps sound a little muddy at very low master volume settings, they should come to life at 1.5 or 2)

Gradually increase the gain knob until playing chords just starts to sound distorted. Every amp is different, yours may reach this point with the gain on 2 or 3, or it may be 5 or 6.

The edge of breakup is more of a range than a point of gain. But now you are in the ballpark and it just needs to be fine-tuned.

Some characteristics/preferences to look for:
– Chords will crunch more than single notes
– Lower pitched notes will crunch more than higher pitched ones.
– Playing harder will yield more crunch, playing softly will clean up the sound.
– Backing off the volume knob on the guitar, say from 10 to 8, will clean up the sound.
– Tone controls on the amp, especially the bass, will effect the amount of breakup. If you turn up the bass, back off the gain to maintain the same behavior from the amp.

It will require a period of experimentation to tweak the gain to exactly where you want it, but make small adjustments. If your amp starts to distort on chords with the gain on 4, you may likely be looking for the sweet spot between 4 and 5.

Many players will aim for a setting that yields a bit of breakup when playing aggressively and a clean tone when playing more softly, and/or a nice crunch with the guitar volume on 10 which cleans up when backed off to 7 or 8. Observe how many players are working the volume knob often.

Once you are getting dialed in to a tone you like, the master volume can be adjusted for the desired volume level without affecting the tone too much. That is, until…

Once the master volume is increased to a certain point, you will start to introduce power amp distortion, which has its own edge of breakup. But as I mentioned previously, you are getting pretty loud at this point. Even at a gig, depending on how powerful your amp is, you may even start getting the stink eye from the soundman.

So that’s the basics. Tweak your tone controls for the tone you desire, adjust your gain knob for amount of distortion, dial in a bit of reverb, and adjust the master volume for overall volume level. Easy peasy. Haha, actually, you may spend the rest of your life making tiny (or not so tiny) adjustments.

One note. A little goes a long way. Blues players have a wide variety of tones, but typically they won’t be heavy handed on the distortion or reverb.

YouTube has many resources that cover all this, some of them are even useful (many are not). Any questions, comments, corrections or additions, don’t be shy. Either I or one of the many folks here who know far more than I do should be able to help out.

Topic

[Garry]

Hey Joe. This is great, you have explained this really well. I’ve just recently received my very first tube amp (Supro Delta King 10) and I’m still experimenting so this info is excellent. Broken down well and I’ll definitely be following these guidelines and seeing/hearing to find out my point of breakup and ‘signature’ tone 😉. Thanks again. 🥸🎸🥸

[Ron M]

Thanks for this. I am an old beginner with electric. I played a bit of acoustic when I was younger. I have a little Cube practice amp which I am really quite pleased with. It is loud enough to make the wife complain, it gives me some simulated amp choices with increasing distortion, I even got some Hendrix feedback, I was so happy, reverberation, tremelo, chorus, flange and delay. I appreciate your explanation of the gain and Master controls, that really clears up a lot of confusion I had. Thank you very much

Ron

[charjo]

Joe,
This is a nice overview of getting a blues tone. Like you mentioned it is a topic that comes up often. I’m going to create a “sticky” for the post, meaning it will stay near the top of posts in the Discuss Your Gear section of the forum and not get buried under the next several posts.
The next piece of the puzzle is how to add a boost or overdrive pedal or stacked overdrive pedals to your basic amp tone. I also like to add a very short or “slap back” delay as part of my basic tone.
John

[Mark H]

It’s worth mentioning a lot of great amps have no master volume on the power amp side. I have a Marshall Power Brake attenuator in the signal chain between power amp output and speaker of a Twin Reverb blackface RI. This essentially gives the amp a master volume function.

The Power Brake does suck some tone, the amp just sounds better without it. But the amp is too loud without it (when playing in small rooms, at home, etc) when the pre-amp volume is sitting on the edge of distortion sweet spot, around 5+

[Mark H]

Correction, I meant my Deluxe Reverb, not Twin Reverb.

Apropos of nothing, I believe the earlier Twins also had no master volume. Fender added one to it in later models, I think with the first silverfaces in the early Seventies(?)

[CT]

Some good general advice in there, well done & nice share. When it comes to tone it’s another one of those time on task kind of things, and it’s important to really get to know your gear. It should be fairly easy to dial in a nice tone on an amp. Something is wrong if it is hard.

Here’s how I dial in my tube amp: https://tonesmiths.wordpress.com/2013/03/28/the-secret-to-quickly-dial-in-a-tube-amplifier/

On my little solid state amps I usually bypass the preamp and presets altogether, put some pedals in the signal chain, and dial them in by ear.

My Youtube Channel

[Mark H]

Thanks CT, I read your interesting blog link on dialing-in tube amp threshold response and will be trying it out.

[CT]

Mark H wrote:

Thanks CT, I read your interesting blog link on dialing-in tube amp threshold response and will be trying it out.

Finding and setting the noise floor on a fairly noisy amp like mine has been very helpful for me. I like that it teaches to use your ears, not just go by numbers on the dials. That first gain “kick in” is the edge of breakup and is really the secret sauce.

My Youtube Channel

[richard t]

I also tried the method CT mentions. It worked very well.

[Joe]

It’s incredible that a trick like that is not common knowledge. Thanks to CT for the link.

[Author]

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