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Tele_Man
Bronze Member
USA
86 Posts |
 Posted - 03/02/2008 : 19:18:44
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Hey Stratosphere (and everyone else please chime in),
In reading through some old threads I came across this comment from you in a thread about the BD-2 (linked below):
quote:
. . . i recommend using the "power amp" setting if you can. set the master volume at just say 8 and put the channel volume low. usually with the master volume set so high, the channel volume will be pretty touchy and should start getting very loud around 2 but it all depends on the amp. . .
I have a single channel tube amp with a volume knob and a gain knob. In the past few months I've started cranking the volume almost all the way (9 or 10) and using the gain knob to adjust the overall loudness. Like you said, it starts to get very loud around 2.
Is what I'm doing the same thing as what you're talking about with using the "power amp" setting in your quoted comment?
And a dumb follow up: why does this seem to sound so much better? I can't put my finger on it exactly, but to me my amp just sounds so much better for a clean sound with the volume high and the gain low. This seems counter-intuitive. What exactly is going on here when using the controls like this?
Thanks for any feedback this community might provide.
Here's the original thread. StratoSphere's comment is the 7th post:
http://www.bossarea.com/forum/topic.asp?TOPIC_ID=2524
Cheers  |
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Laurie
Double Platinum Member
Canada
4854 Posts |
Posted - 03/02/2008 : 20:47:34
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quote:
I have a single channel tube amp with a volume knob and a gain knob. In the past few months I've started cranking the volume almost all the way (9 or 10) and using the gain knob to adjust the overall loudness.
And a dumb follow up: why does this seem to sound so much better? I can't put my finger on it exactly, but to me my amp just sounds so much better for a clean sound with the volume high and the gain low. This seems counter-intuitive. What exactly is going on here when using the controls like this?
G'day Tele_Man! I don't know what amp you are referring to, but I think I can tell you in a generic sense what's going on...
Simplistically
Tube amps have two "stages" - the pre-amp and the power amp. Different tubes, different gain structures, very different sounds. Generally, power amp stages are designed to give minimal distortion, but in a tube amp of course, if you drive the stage really hard you get lots of lovely odd harmonic distortion (the "good" distortion that tubes are known for).
Often the pre-amp and power amp stages are wired up so that:
- the "gain" knob controls the drive/overdrive inside the pre-amp stage
- the "volume" knob controls the input voltage to the power amp (how much of the sound produced in the pre-amp gets sent to the power amp)
So... turn up the gain and the volume down, and the distortion predominately comes from the pre-amp. In this situation, lots of gain in the pre-amp tubes makes them distort, then only a little of the distorted signal out of the pre-amp is given to the power amp which doesn't add much distortion.
Turn up the volume and turn down the gain, and the distortion predominately comes from the power amp. In this situation, the pre-amp isn't distorting much because the gain is turned down. With the volume up, the distortion you can hear is from power amp.
It is often thought that power amp distortion is actually nicer to the ear than pre-amp distortion. That's why tube amps sound better as the power amp warms up.
To all the other folks reading this and thinking "lauries2 is out to lunch with this"... please modify or correct anything I've screwed up (and I'm sure there'll be something!).
Anyway, I run my JCM600 Marshall head on the clean channel with the gain at about 3 and the master volume at about 7 for just this reason. I have a line driver last in the pedal chain so if I want some pre-amp distortion, I kicking that on overdrives the pre-amp a bit.
Regards,
Laurie
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FRANZONI
Double Platinum Member
Ireland
3543 Posts |
Posted - 03/03/2008 : 12:39:39
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no i think you covered it pretty well bro'.... i have two non master volume amps,one is a marshall superbass but i use it for guitar and the other is a selmer... i 'jump' the channels using a small patch lead,usually on these amps one channel is normal and the other is treble,so the volume controls when jumped,act like a master bass and treble controls as well as volume....... i also have a musicman combo which is master volume and i use it it the way you described the only difference is..i wouldn't whack the master up full..i normally have the master on about 7 or 8 and the channel/gain on about 4 or 5..i find if the channel volume is set too low the sound from the amp is lacking a bit of 'body'.. maybe it's just the musicman 'cause it has a solid state pre amp section and valve output section and phase inverter..... |
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FRANZONI
Double Platinum Member
Ireland
3543 Posts |
Posted - 03/03/2008 : 12:44:21
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| no i think you covered it pretty well bro'.... i have two non master volume amps,one is a marshall superbass but i use it for guitar and the other is a selmer... i 'jump' the channels using a small patch lead,usually on these amps one channel is normal and the other is treble,so the volume controls when jumped,act like a master bass and treble controls as well as volume....... i also have a musicman combo which is master volume and i use it it the way you described the only difference is..i wouldn't whack the master up full..i normally have the master on about 7 or 8 and the channel/gain on about 4 or 5..i find if the channel volume is set too low the sound from the amp is lacking a bit of 'body'.. maybe it's just the musicman 'cause it has a solid state pre amp section and valve output section and phase inverter..... |
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DeFrag
Moderator
USA
3409 Posts |
Posted - 03/03/2008 : 16:17:35
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| Delete one of your posts Franzoni! |
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FRANZONI
Double Platinum Member
Ireland
3543 Posts |
Posted - 03/05/2008 : 01:41:48
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quote:
Originally posted by DeFrag
Delete one of your posts Franzoni!
I tried but it won't let me.....
don't worry DeFrag i reckon you will hit four stars before me....anyway it didn't count as two....... .... |
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DeFrag
Moderator
USA
3409 Posts |
Posted - 03/05/2008 : 02:16:56
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quote:
Originally posted by FRANZONI
quote:
Originally posted by DeFrag
Delete one of your posts Franzoni!
I tried but it won't let me.....
don't worry DeFrag i reckon you will hit four stars before me....anyway it didn't count as two...........
Hah! Bummer. I only meant for sake of cleanliness on the board really.
Truth be told, I really don't see why humans are so enamored with even numbers like "The Big 5-0", 1000 posts, or 1st place. People like to toot their own horn & be recognized but I see it as false accolades. The only thing we achieve in life other than playing guitar & getting to procreate on Saturday nights is the friendships we maintain. I feel lucky to be alive considering the fact that indeed, I was the fastest sperm of the bunch & I could just as easily be someone else right now.. Wait a minute, I just blew my mind! 
If you guys wanna party at 1000, knock yourselves out. I'll be the one in the back makin' out with the fat chick. 
Never odd or eveN |
Edited by - DeFrag on 03/05/2008 02:20:24 |
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Hey StratoSphere . . . a question for you.
