Question for some tube gurus

[thebigcheese]

I upgraded to a tube amp (Blues Jr.) about a year ago and I don't think I could ever go back. One thing I assumed I still needed, though, was a Metal Muff because I thought the only way to get heavy metal distortion was with a pedal. Well, I was reading something online and came across an article where Kirk Hammett said he doesn't like to use pedals much and uses just the amp distortion. I had figured for a while that the "Marshall tone" was just because Marshalls had a special distortion channel that people happened to like, but then I got to thinking that maybe he was actually overdriving the amp. So I tried that with my Tube Screamer clone and found that I could get it to sound very similar to my Metal Muff.

So I guess my overall question is whether he would be using a special distortion channel on the amp or if he is overdriving it, and if it's overdrive, could it really be power tube distortion on such a loud amp? People always say that power tube distortion is what to strive for, but I'm not sure how that's really possible with the wattage those amps put out, and I know I can't get strictly power tube distortion on my amp because it doesn't have an effects loop. So maybe someone can clear that up for me, too.

 

[ggunn]

I upgraded to a tube amp (Blues Jr.) about a year ago and I don't think I could ever go back. One thing I assumed I still needed, though, was a Metal Muff because I thought the only way to get heavy metal distortion was with a pedal. Well, I was reading something online and came across an article where Kirk Hammett said he doesn't like to use pedals much and uses just the amp distortion. I had figured for a while that the "Marshall tone" was just because Marshalls had a special distortion channel that people happened to like, but then I got to thinking that maybe he was actually overdriving the amp. So I tried that with my Tube Screamer clone and found that I could get it to sound very similar to my Metal Muff.

So I guess my overall question is whether he would be using a special distortion channel on the amp or if he is overdriving it, and if it's overdrive, could it really be power tube distortion on such a loud amp? People always say that power tube distortion is what to strive for, but I'm not sure how that's really possible with the wattage those amps put out, and I know I can't get strictly power tube distortion on my amp because it doesn't have an effects loop. So maybe someone can clear that up for me, too.

What's commonly referred to as the "Marshall sound" comes from driving EL34 power tubes into distortion/soft clipping, and it's LOUD. You can drive lower power tubes hard and get distortion at lower volume, but it won't sound quite the same. I'm not sure what the connection you see between FX loops and tube distortion; old Marshalls didn't have them or master volumes, either.

 

[thebigcheese]

What's commonly referred to as the "Marshall sound" comes from driving EL34 power tubes into distortion/soft clipping, and it's LOUD. You can drive lower power tubes hard and get distortion at lower volume, but it won't sound quite the same. I'm not sure what the connection you see between FX loops and tube distortion; old Marshalls didn't have them or master volumes, either.

Maybe I was being a bit scatterbrained. What I meant is just that people talk about preamp distortion as "bad" and say that you should shoot for only power tube distortion by sticking the overdrive pedals in the fx loop.

So they just have the one volume knob? How does that work? And does that mean preamp distortion is also included in that?

On a somewhat related note, I've noticed that pick squeals don't work nearly as well when I'm just driving my tubes vs. using the Metal Muff.

 

[antichef]

Different tube amps have different circuits and transformers (and speakers, etc.), and can sound very different from one another as a result. I've got a Blues Jr. and also a JCM 800 half stack - they sound very different from each other. I used to use a tube screamer to push the JCM 800 and got probably more distortion than I really wanted, but it sounded good. These days, I like it with no pedals. Quite a bit of the distortion on the JCM 800 comes from the preamp tubes, and it sounds good to me - the amp hits a really sweet spot when the master is between 5 and 6, but that's *real* loud and I don't get to do it very often. Due to loudness issues around the house, I wind up playing the Blues Jr. (and other small amps) a lot more - but it's definitely two completely different sounds.

 

[notCardio]

I think you've been misinformed

or perhaps misunderstood something you read or heard. I would venture to say that most of the tube distortion, or any distortion for that matter, that you hear is from the preamp stage. That's really what a distortion pedal is - a preamp. Most modern amps have gain controls for both the preamp section (often labelled as 'gain'), and the power amp section (often labelled as 'volume'). This way, you can turn up the preamp to where it overdrives (distorts), while leaving the volume at a reasonable level. Having said that, the most desirable tone of many amps is acheived by also running the power tubes at overdriven levels. Power tube distortion is a little different than preamp tube distortion, tone-wise. The classic 'Marshall stack' sound came from running it flat out. Pretty much the same with some of the early smaller Fender amps. A Marshall power section on '11', though, is pratical only in a recording studio that's set up to handle it, or a pretty large venue. Unless you have an attenuator, but that's another topic.

I don't know where you got the idea that preamp distortion is bad. It's bad if you don't want it, but a majority of preamps are built specifically to distort in a pleasing way when you want them to.

And tube amps are no more or less loud than a comparable solid state (non-tube) amp. The fact that an amp is or isn't tube has no real bearing on that fact (well, that's not entirely true, but for the sake of this discussion it is).

 

[Farview]

Kirk and James use Mesa Mark IV amps. It's a completely different sound than the Marshall gives you, which is different than your amp, a fender twin, etc...

Different tube circuits break up differently and can sound quite different.

There is nothing wrong with preamp distortion or anything necessarily 'better' about power amp distortion. They are just two different types of distortion that you can manage to create the sound you want. Don't forget about speaker breakup, that is another type of distortion that is part of your guitar sound.

Some people favor the power amp distortion that comes from cranking an amp, but without a good amount of preamp distortion these sounds don't have enough gain for metal.

Some people favor preamp distortion, but these sounds can get fuzzy.

Finding the right combination of preamp and power amp distortion is the way to get gain, compression and clarity out of a distorted guitar tone.

Then you need to choose a speaker that breaks up early or stays relatively clean...

The combinations are endless.

 

[thebigcheese]

Ok, makes sense that different amps break up differently, I just wasn't sure if it was a product of that. I don't really expect to be able to get super metal tones out of a Fender amp, but it does do pretty well, all things considered. I did notice that some of the more metaly part of the distortion doesn't come unless I turn up the master knob, so I'm guessing that part is mostly from the power amp distorting. I'll have to play around a bit more and see. I do have an attenuator, but it's only for 20w, so I don't want to crank the amp up tooooo much, at least not for too long.