Why is it......

[Cleekster]

Why is it that every time an amp company crams 5 gain stages in an preamp that guitarists jump to the conclusion that the power section:

1)is incapable of distorting
or
2)isn't designed to distort or at least wasn't intended to serve that purpose.

In my experience less gain and more volume ALWAYS SOUNDS BIGGER AND BETTER i don't care if it's a fender bassman or a mesa rectifier.

having said that....let me say that not everyone can crank an amp so high-gain preamps have thier uses for some ...and i love high gainers 'cause they slam the power stage harder which gives me power stage saturation sooner rather than later.

but i see no useful purpose in spreading misinformation to people who don't know......WHY do people feel the need to continually perpetuate this MYTH???? :?

(okay rant over :mrgreen: )

 

[MrMarkIII]

"i love high gainers 'cause they slam the power stage harder which gives me power stage saturation sooner rather than later."

Um, sorry, I beg to differ. The power stage ONLY gets slammed harder by cranking the master. High gain in the pre-amp has little, if any, effect.
However, "less gain and more volume ALWAYS SOUNDS BIGGER AND BETTER"
could not be more true. You are correct, sir!
My two cents.

 

[Cleekster]

"i love high gainers 'cause they slam the power stage harder which gives me power stage saturation sooner rather than later."

Um, sorry, I beg to differ. The power stage ONLY gets slammed harder by cranking the master. High gain in the pre-amp has little, if any, effect.
However, "less gain and more volume ALWAYS SOUNDS BIGGER AND BETTER"
could not be more true. You are correct, sir!
My two cents.

What i mean't was that more gain stages= more signal strength hitting the PI thus driving the power tubes into saturation sooner.



for example;

on my recto my green channel has 3 gain stages and my red ch. has 5.......i find to get the same amount of power stage saturation that i get on the red channel with the masterknob on 5 i have to turn the master all the way up on the green channel.

The master knob on boogies is essentially determining how hard your hitting the PI tube and the harder you drive the PI the sooner you hit break up......it is also my experience that slamming the PI will give you the majority of that "Cranked" sound, it just won't add much distortion which is where the power tubes come in.

i appreciate you putting in your $.02

 

[R_ADKINS80]

Another myth lies in this post......5 preamp tubes DOES NOT = 5 gain stages. Mesas only have 3 gain stages. FX loop, reverb and PI tubes are not in the gain stages.

 

[domct203]

Another myth lies in this post......5 preamp tubes DOES NOT = 5 gain stages. Mesas only have 3 gain stages. FX loop, reverb and PI tubes are not in the gain stages.

In the Recto series the Green channel has 3 gain stages, the Orange and Red channels have 4.

For Example, the Roadster and RKII Preamp tube functions are:

V1A=First Gain Stage
V1B=Second Gain Stage
V2A=Third Gain Stage Ch 1&2
V2B=Third Gain Stage Ch 3&4
V3A=Fourth Gain Stage Ch 3&4
V3B=Tone Stack Driver

The Tone Stack Driver could be considered an additional gain stage as well.

Remember, a 12AX7 is really two tubes in one bottle.

Dom

 

[UltraGary]

And let me say,..... perhaps the clarification of the,...... shall we say......to coin a phrase....... (oh wait, now I'm not saying anything either)

 

[dmcguitar]

well i think there is part truth in the matter. for certain amps. some amps are designed to have a clean power section and just amplifiy the tone of the preamp. I think the 5150 is sorta like that... at least it has a really clean power amp either way.

 

[YellowJacket]

Why is it that every time an amp company crams 5 gain stages in an preamp that guitarists jump to the conclusion that the power section:

1)is incapable of distorting
or
2)isn't designed to distort or at least wasn't intended to serve that purpose.

In my experience less gain and more volume ALWAYS SOUNDS BIGGER AND BETTER i don't care if it's a fender bassman or a mesa rectifier.

having said that....let me say that not everyone can crank an amp so high-gain preamps have their uses for some ...and i love high gainers 'cause they slam the power stage harder which gives me power stage saturation sooner rather than later.

but i see no useful purpose in spreading misinformation to people who don't know......WHY do people feel the need to continually perpetuate this MYTH???? :?

(okay rant over :mrgreen: )

While we can all quibble over pedantic details, I totally agree with the spirit of your post. I don't know how to describe it in technical terms--i.e. I am not physically aware of what the amp is doing during any particular phase of its operation--but I do know what you are talking about. It is that sweet spot with the volume up around 10 o'clock where the recto starts to sound much more liquid, singing, and full. You can tell. The buzzing stops and the amp starts to roar. I know a high gain amp isn't a pre-amp tube machine exclusively because if it was, a Valvestate amp would sound virtually identical to one that has a tube power section as well.
Ok, lets look at some science. :idea:

***************

**basic sound science.**
Skip if you know this already.

Virtually all naturally occurring sounds that result from a resonating body produce more than one frequency. There is the lowest frequency which is the fundamental--the pitch we hear--and the higher frequencies that we call overtones. The harmonic series refers to the mathematical pattern of overtones that results from a resonating body, such as a metal guitar string, as it vibrates evenly. The entire length of the string vibrates at the fundamental but there are other frequencies that are occurring simultaneously as well. When you divide a string in half, the frequency that sounds is an octave above the fundamental. This is an octave harmonic.

The octave harmonic is a node, which is a place on the string with less motion because there are less vibration patterns occurring there at once. You can then divide the string into thirds and get a pitch sounding an octave and a fifth above the fundamental. Then you divide the string into four parts and get a pitch that sounds two octaves higher than the fundamental, then you divide it into five parts and get a pitch that sounds two octaves and a third higher than the fundamental, and so on. So, if we are talking about the G string on the guitar, the fundamental is a G, so we get another G an octave higher, then a D, then another G, then a B, then a D, E, a pitch between an F and a F#, a G, an A, an out of tune B, a C, C#, D etc. As the overtones get higher, they get closer together and less loud in comparison with the volume of the fundamental.

So how does this apply to guitar tone? Well, a clean guitar sound is comprised of sine waves, so waves in an S shape. As the tone distorts, the peaks and valleys are cut of which makes the wave shape become more and more square. Theoretically speaking, a perfectly square wave has infinite overtones. What real world sound has close to a square wave? Well, a distortion guitar. Basically, there is a huge 'noise' component to a guitar sound. The overtones sound very loudly in comparison to, say a clean guitar, or a Cello. This is even more true of metal tone, where the overtones are really maximized. The ease at which harmonics pop out on a guitar is dictated by the relative loudness of overtones in comparison to the fundamental. The more equal in volume they are, the more of an aggressive squeal you get. Basically, overtones add intensity, brilliance, perceived loudness, and aggression to a sound.
To put it in perspective, if you record a Cello playing a very VERY quiet passage and put it through a massive sound system at 160 db, it will still sound like a quiet cello. If you play a cello very loud and play it back on laptop speakers, it still sounds super intense, even if it is quiet. So overtones affect the quality of the sound while loudness affects the decibel level.

So, getting back to guitars. . . .
:!: **end science lesson** :!:

**********

For our purposes, it is sufficient to say that overtones are guitar tone. If you disagree, read the science lesson above. If you still disagree, remove the overtones in your tone. If you do that, your guitar will sound like a flute! The pattern of loudness of certain overtones in relation to others is the result of how our knobs are set on our amplifiers. They are also the result of the pickups transmitting an electrical signal from our guitar amps, our tubes working hard, and the speakers on the amp.
All these things affect tone.
So, to answer the question about which tubes affect tone in what way, we have to control all other factors and only manipulate the control variable. Luckily for us, such a model exists in the real world.

8) Thank you Marshall, for building the valvestate amplifier. :lol: If any amp works on preamp tube distortion alone, it is a valvestate. The idea is great in theory: Tubes are unreliable and tempermental. If distortion comes from preamp clipping alone, why do we need tubes in the power section anyway?? Lets backtrack for the sake of argument here. Scientists have blabbed on and on about how the audio frequencies generated by tubes and transistors are identical. They thought guitarists were crazy for the longest time but then someone got a bright idea. Guitar amplifiers DISTORT. To audiophiles, distortion is undesirable so the scientists had never thought to measure the frequency response of tubes verses transistors while clipping. **DUH**

So the scientists 'got smart' and they did a study on the overtones generated by tubes verses transistors during clipping. I know this because I read it. They found that the sound reproduction is indeed virtually identical UNTIL clipping is reached. THEN it changes drastically. Tubes soft clip and have a massive amount of headroom whereas transistors hard clip and have very small amount of headroom. Basically, the overtones generated change drastically at this point of clipping which is why tubes sound musical and transistors sound harsh.

Tubes:
Quiet sine wave --------------> soft clip -----------> Hard clip. loud
-Odd order harmonics emphasized 1, 3, 5, 7, 9 etc.
-Sweet tone
-huge dynamic range at the threshold of distortion.
-Lots of headroom.

Transistors:
quiet sine wave -------------> loud sine wave -> Super hard clip just a hair louder
-Even order harmonics emphasized. 2, 4, 6, 8, 10 etc.
-harsh tone
-small dynamic range at the threshold of distortion
-very little headroom

SO, if the power section was not involved at all in clipping in a high gain amplifier, the audio response would be the same whether the power section of an amp was built with transistors or tubes. Since they sound different, one must conclude that the power section of a tube amp IS clipping, at least a bit. The thing to remember about a clip is that a soft clip won't necessarily sound like huge distortion right off the hop. It sounds 'glassy' and 'sparkly'. Notice how you can basically NEVER get that sort of effect with a solid state amp? Just because you aren't getting a high level of gain from an all tube power section doesn't mean it isn't being provoked into clipping at all.

So, if high gain tone is created only by preamp distortion, a valvestate and a high gain tube head should sound extremely similar if not identical and they most DEFINITELY do not. So if we look at this scientifically, we have to conclude that the power section of the amp must be, in some way, responsible for tone, even if it is not putting out a gain level of ten.

What we don't realize as guitarists is that we use barely a hair of the power an amp is capable of running. You need one watt per speaker to get the correct musical response from them. The thing is that they're throwing out 100db at a metre at this point, which is FRIKING LOUD!!! Volume pots have a logrhythmic taper because we hear that as a linear increase. (Psychoacoustics are weird. We need to increase sound pressure by ten fold to hear a doubling of volume) The result of this is that even at twelve o'clock on the volume knob, we are only using a small fraction of the power the amp is capable of generating. Most likely, it is one tenth the power. So ya, if we are running at half volume on a Dual, that is approximately ten watts and if we run at a quarter volume that is around one watt. This is why dropping an amp to fifty watts makes so very little difference on the perception of maximum volume, but has such a significant effect on how low a volume the power section will clip. Basically, you get that overdriven sound sooner and sooner as you reduce the amps power with the trade off that it looses that ball crushing thump and clean headroom. In a perfect world, you need an amp that has 100watts clean and 10 watts gain with a different speaker cab for each.

Once you reach a certain power level on the amp, the speaker becomes the lowest common denominator a.k.a. the limiting factor. You HAVE to run a watt per speaker to get the speaker to respond enough and at that volume they are throwing 97 - 100db / metre. Hard working speakers really adds warmth and helps tame the buzzies but this--as well as power section clipping--comes with volume. This is why I think anything below about a 10watt amp is stupid.
The thing to remember is that if you are planning on running really low wattage for tone at low volumes, you need to have speakers that are designed to handle low wattage otherwise the amp can't do squat. Using a 4 x 12 with 15 - 25watt speakers such as the Alnico Blue, or G12m heritage will allow the amp to retain some of the low end thump and aggression so it will still sound like it is pounding, even though it will most likely get eaten alive by the drummer. (This sort of setup works the best at stodgy religious institutions where they want rock and roll, but without the volume.)

I think with a Mesa Dual Rectifier, or any other high gain amplifier, it is a question of how MUCH the power section distorts. I think just a bit of clip is perfect since it really rounds out the tone by smoothing the sound from the preamp section while retaining a good amount of tightness. I've pushed the power section into severe clipping and at that point, you might as well turn the gain way down because the amp becomes a different machine. I also know a guy who was doing recording for some local bands back on the prairies and he always ran his rectifier into hard power clipping because he liked the sound better.

I think the whole long winded point is this: Guitars, pickups, rectifier tubes, preamp tubes, power amp tubes, and guitar speaker, and guitar speaker enclosures all play a role in sound creation for a guitar amplifier and we cannot say that any one component is not necessary. The people who thought the power section on a high gain head didn't get pushed into clipping built the valvestate and the outcome proved them wrong.

 

[Cleekster]

Another myth lies in this post......5 preamp tubes DOES NOT = 5 gain stages. Mesas only have 3 gain stages. FX loop, reverb and PI tubes are not in the gain stages.

Well the manuel for my rectoverb says that V3 is the red ch. 4th & 5th gain stages.......

 

[ryjan]

:shock:
Yellowjacket, my eyes are starting to cross! LOL

 

[Cleekster]

Why is it that every time an amp company crams 5 gain stages in an preamp that guitarists jump to the conclusion that the power section:

1)is incapable of distorting
or
2)isn't designed to distort or at least wasn't intended to serve that purpose.

In my experience less gain and more volume ALWAYS SOUNDS BIGGER AND BETTER i don't care if it's a fender bassman or a mesa rectifier.

having said that....let me say that not everyone can crank an amp so high-gain preamps have their uses for some ...and i love high gainers 'cause they slam the power stage harder which gives me power stage saturation sooner rather than later.

but i see no useful purpose in spreading misinformation to people who don't know......WHY do people feel the need to continually perpetuate this MYTH???? :?

(okay rant over :mrgreen: )

While we can all quibble over pedantic details, I totally agree with the spirit of your post. I don't know how to describe it in technical terms--i.e. I am not physically aware of what the amp is doing during any particular phase of its operation--but I do know what you are talking about. It is that sweet spot with the volume up around 10 o'clock where the recto starts to sound much more liquid, singing, and full. You can tell. The buzzing stops and the amp starts to roar. I know a high gain amp isn't a pre-amp tube machine exclusively because if it was, a Valvestate amp would sound virtually identical to one that has a tube power section as well.
Ok, lets look at some science. :idea:

***************

**basic sound science.**
Skip if you know this already.

Virtually all naturally occurring sounds that result from a resonating body produce more than one frequency. There is the lowest frequency which is the fundamental--the pitch we hear--and the higher frequencies that we call overtones. The harmonic series refers to the mathematical pattern of overtones that results from a resonating body, such as a metal guitar string, as it vibrates evenly. The entire length of the string vibrates at the fundamental but there are other frequencies that are occurring simultaneously as well. When you divide a string in half, the frequency that sounds is an octave above the fundamental. This is an octave harmonic.

The octave harmonic is a node, which is a place on the string with less motion because there are less vibration patterns occurring there at once. You can then divide the string into thirds and get a pitch sounding an octave and a fifth above the fundamental. Then you divide the string into four parts and get a pitch that sounds two octaves higher than the fundamental, then you divide it into five parts and get a pitch that sounds two octaves and a third higher than the fundamental, and so on. So, if we are talking about the G string on the guitar, the fundamental is a G, so we get another G an octave higher, then a D, then another G, then a B, then a D, E, a pitch between an F and a F#, a G, an A, an out of tune B, a C, C#, D etc. As the overtones get higher, they get closer together and less loud in comparison with the volume of the fundamental.

So how does this apply to guitar tone? Well, a clean guitar sound is comprised of sine waves, so waves in an S shape. As the tone distorts, the peaks and valleys are cut of which makes the wave shape become more and more square. Theoretically speaking, a perfectly square wave has infinite overtones. What real world sound has close to a square wave? Well, a distortion guitar. Basically, there is a huge 'noise' component to a guitar sound. The overtones sound very loudly in comparison to, say a clean guitar, or a Cello. This is even more true of metal tone, where the overtones are really maximized. The ease at which harmonics pop out on a guitar is dictated by the relative loudness of overtones in comparison to the fundamental. The more equal in volume they are, the more of an aggressive squeal you get. Basically, overtones add intensity, brilliance, perceived loudness, and aggression to a sound.
To put it in perspective, if you record a Cello playing a very VERY quiet passage and put it through a massive sound system at 160 db, it will still sound like a quiet cello. If you play a cello very loud and play it back on laptop speakers, it still sounds super intense, even if it is quiet. So overtones affect the quality of the sound while loudness affects the decibel level.

So, getting back to guitars. . . .
:!: **end science lesson** :!:

**********

For our purposes, it is sufficient to say that overtones are guitar tone. If you disagree, read the science lesson above. If you still disagree, remove the overtones in your tone. If you do that, your guitar will sound like a flute! The pattern of loudness of certain overtones in relation to others is the result of how our knobs are set on our amplifiers. They are also the result of the pickups transmitting an electrical signal from our guitar amps, our tubes working hard, and the speakers on the amp.
All these things affect tone.
So, to answer the question about which tubes affect tone in what way, we have to control all other factors and only manipulate the control variable. Luckily for us, such a model exists in the real world.

8) Thank you Marshall, for building the valvestate amplifier. :lol: If any amp works on preamp tube distortion alone, it is a valvestate. The idea is great in theory: Tubes are unreliable and tempermental. If distortion comes from preamp clipping alone, why do we need tubes in the power section anyway?? Lets backtrack for the sake of argument here. Scientists have blabbed on and on about how the audio frequencies generated by tubes and transistors are identical. They thought guitarists were crazy for the longest time but then someone got a bright idea. Guitar amplifiers DISTORT. To audiophiles, distortion is undesirable so the scientists had never thought to measure the frequency response of tubes verses transistors while clipping. **DUH**

So the scientists 'got smart' and they did a study on the overtones generated by tubes verses transistors during clipping. I know this because I read it. They found that the sound reproduction is indeed virtually identical UNTIL clipping is reached. THEN it changes drastically. Tubes soft clip and have a massive amount of headroom whereas transistors hard clip and have very small amount of headroom. Basically, the overtones generated change drastically at this point of clipping which is why tubes sound musical and transistors sound harsh.

Tubes:
Quiet sine wave --------------> soft clip -----------> Hard clip. loud
-Odd order harmonics emphasized 1, 3, 5, 7, 9 etc.
-Sweet tone
-huge dynamic range at the threshold of distortion.
-Lots of headroom.

Transistors:
quiet sine wave -------------> loud sine wave -> Super hard clip just a hair louder
-Even order harmonics emphasized. 2, 4, 6, 8, 10 etc.
-harsh tone
-small dynamic range at the threshold of distortion
-very little headroom

SO, if the power section was not involved at all in clipping in a high gain amplifier, the audio response would be the same whether the power section of an amp was built with transistors or tubes. Since they sound different, one must conclude that the power section of a tube amp IS clipping, at least a bit. The thing to remember about a clip is that a soft clip won't necessarily sound like huge distortion right off the hop. It sounds 'glassy' and 'sparkly'. Notice how you can basically NEVER get that sort of effect with a solid state amp? Just because you aren't getting a high level of gain from an all tube power section doesn't mean it isn't being provoked into clipping at all.

So, if high gain tone is created only by preamp distortion, a valvestate and a high gain tube head should sound extremely similar if not identical and they most DEFINITELY do not. So if we look at this scientifically, we have to conclude that the power section of the amp must be, in some way, responsible for tone, even if it is not putting out a gain level of ten.

What we don't realize as guitarists is that we use barely a hair of the power an amp is capable of running. You need one watt per speaker to get the correct musical response from them. The thing is that they're throwing out 100db at a metre at this point, which is FRIKING LOUD!!! Volume pots have a logrhythmic taper because we hear that as a linear increase. (Psychoacoustics are weird. We need to increase sound pressure by ten fold to hear a doubling of volume) The result of this is that even at twelve o'clock on the volume knob, we are only using a small fraction of the power the amp is capable of generating. Most likely, it is one tenth the power. So ya, if we are running at half volume on a Dual, that is approximately ten watts and if we run at a quarter volume that is around one watt. This is why dropping an amp to fifty watts makes so very little difference on the perception of maximum volume, but has such a significant effect on how low a volume the power section will clip. Basically, you get that overdriven sound sooner and sooner as you reduce the amps power with the trade off that it looses that ball crushing thump and clean headroom. In a perfect world, you need an amp that has 100watts clean and 10 watts gain with a different speaker cab for each.

Once you reach a certain power level on the amp, the speaker becomes the lowest common denominator a.k.a. the limiting factor. You HAVE to run a watt per speaker to get the speaker to respond enough and at that volume they are throwing 97 - 100db / metre. Hard working speakers really adds warmth and helps tame the buzzies but this--as well as power section clipping--comes with volume. This is why I think anything below about a 10watt amp is stupid.
The thing to remember is that if you are planning on running really low wattage for tone at low volumes, you need to have speakers that are designed to handle low wattage otherwise the amp can't do squat. Using a 4 x 12 with 15 - 25watt speakers such as the Alnico Blue, or G12m heritage will allow the amp to retain some of the low end thump and aggression so it will still sound like it is pounding, even though it will most likely get eaten alive by the drummer. (This sort of setup works the best at stodgy religious institutions where they want rock and roll, but without the volume.)

I think with a Mesa Dual Rectifier, or any other high gain amplifier, it is a question of how MUCH the power section distorts. I think just a bit of clip is perfect since it really rounds out the tone by smoothing the sound from the preamp section while retaining a good amount of tightness. I've pushed the power section into severe clipping and at that point, you might as well turn the gain way down because the amp becomes a different machine. I also know a guy who was doing recording for some local bands back on the prairies and he always ran his rectifier into hard power clipping because he liked the sound better.

I think the whole long winded point is this: Guitars, pickups, rectifier tubes, preamp tubes, power amp tubes, and guitar speaker, and guitar speaker enclosures all play a role in sound creation for a guitar amplifier and we cannot say that any one component is not necessary. The people who thought the power section on a high gain head didn't get pushed into clipping built the valvestate and the outcome proved them wrong.

I agree with alot of what you're saying but let me add a few things:

I run my recto with the following settings
Gain-8:30
master-12:00
output-2:30
the majority of my OD comes from the power amp.... you were saying that if you turn the output up at 12:00 your not really pushing the power section but consider this.

if i use the gain/master settings above on the red channel....

GTE34Ls(#4) i hit break-upat 8;30 on the output
and with GT6L6GE's(#4) i hit break-up at around 10:00

still using the GTE34ls's as an example...if i turn the master setting down to 9:00 i generally wouldn't hear break-up until 11-12:00 so i think that how hard you slam the PI plays a major role in determining how much power tube OD you get and how soon you get it IME.

 

[YellowJacket]

I agree with alot of what you're saying but let me add a few things:

I run my recto with the following settings
Gain-8:30
master-12:00
output-2:30
the majority of my OD comes from the power amp.... you were saying that if you turn the output up at 12:00 your not really pushing the power section but consider this.

if i use the gain/master settings above on the red channel....

GTE34Ls(#4) i hit break-upat 8;30 on the output
and with GT6L6GE's(#4) i hit break-up at around 10:00

still using the GTE34ls's as an example...if i turn the master setting down to 9:00 i generally wouldn't hear break-up until 11-12:00 so i think that how hard you slam the PI plays a major role in determining how much power tube OD you get and how soon you get it IME.

Ok, I was talking about high gain amps in general. Also keep in mind that I have a two channel recto so I don't have an overall master. I have a volume for channel one, a volume for channel two, and a loop master that is only effected when I activate the effects loop. So for my amp, I get power amp distortion starting in earnest on the red channel when it is set to modern starting at 12:00. If I use vintage mode, I get it when I have the dial cranked.

A recto is unique because when you switch from vintage to modern on a channel, you add a gain stage. (for those of you who don't believe me, read the manual) This changes the output level from the preamp which in turn causes the amp to be louder overall. When I swap from vintage to modern on my dual, the volume does indeed become significantly louder. The volume pot has enough of a taper or whatever you call it that you can crank the amp when you are running in either raw or vintage mode. This allows the user to run the amp and balance the levels between channels.
(This way Channel 2 in raw mode can be as loud as Channel 3 in modern mode)

So basically, with the master up halfway in modern mode, you have the power section running really hard. Also, if EL-34s have less headroom, you'll get distortion earlier. It makes the amp sound like it is blasting louder at lower volumes.

Generally, the way to get power tube distortion at lower volumes is 1) use EL-34s. 2) run tube rectifiers 3) run the variac setting on spongy. All this will lower clean headroom which is equivalent to increasing distortion at lower volumes. The downside is that you get less grunt and less thump.

 

[Cleekster]

Okay...i've never played a older rcto so i see what you're saying.

The only difference between Modern and vintage in a modern recto is the absence of a negative feedback loop in the power section which is responsible for the extra volume and aggressiveness....I sometimes run the preamp out into my line 6's auxilary in for recording so i can attest to the fact that there isn't ANY difference in the preamp section

 

[YellowJacket]

Okay...i've never played a older rcto so i see what you're saying.

The only difference between Modern and vintage in a modern recto is the absence of a negative feedback loop in the power section which is responsible for the extra volume and aggressiveness....I sometimes run the preamp out into my line 6's auxilary in for recording so i can attest to the fact that there isn't ANY difference in the preamp section

Ok, so you are talking about the effect of how high channel volume is set compared to the master volume on a three channel head. I guess most users postulate that the channel volume controls the preamp and the master volume controls the power section?

Are there any amp builders here? I don't know that things are really that cut and dry or simple, for that matter. I wonder why Mesa uses a master volume for their three channel amps? Perhaps it has something to do with balancing levels when the effects loop is activated. After all, the only time I can run the master volume on my 2 channel amp is when the effects loop is activated. Maybe it is a convenient way to turn the amp up and down with one knob instead of three?

At any rate, I get the impression that since both the channel volumes and the master volume affect the overall volume of the amp, they control the power section of the amp in some capacity. Technically, the gain knob is the one that controls the volume of the preamp.

This thread is becoming excessively pedantic. If we ignore the triviality, we are left with the solid fact that power tubes contribute to tone and when they are working hard, the amp sounds better.

 

[Cleekster]

Okay...i've never played a older rcto so i see what you're saying.

The only difference between Modern and vintage in a modern recto is the absence of a negative feedback loop in the power section which is responsible for the extra volume and aggressiveness....I sometimes run the preamp out into my line 6's auxilary in for recording so i can attest to the fact that there isn't ANY difference in the preamp section

Ok, so you are talking about the effect of how high channel volume is set compared to the master volume on a three channel head. I guess most users postulate that the channel volume controls the preamp and the master volume controls the power section?

Are there any amp builders here? I don't know that things are really that cut and dry or simple, for that matter. I wonder why Mesa uses a master volume for their three channel amps? Perhaps it has something to do with balancing levels when the effects loop is activated. After all, the only time I can run the master volume on my 2 channel amp is when the effects loop is activated. Maybe it is a convenient way to turn the amp up and down with one knob instead of three?

At any rate, I get the impression that since both the channel volumes and the master volume affect the overall volume of the amp, they control the power section of the amp in some capacity. Technically, the gain knob is the one that controls the volume of the preamp.

This thread is becoming excessively pedantic. If we ignore the triviality, we are left with the solid fact that power tubes contribute to tone and when they are working hard, the amp sounds better.

The gain knob basically adds distortion, the channel volume(master on mesa's) is pre-PI and is essentially a volume for the preamp/fx send(fx loops are genreally Post PI)and the output knob is a PPIMV....IMO it's alot more flexable to have both but there are lot's of amps(5150, marshall JCM 800/2000,etc...)that only have a Pre-PIMV which in order to distort the power tubes you have to slam the PI....but on an amp with both you can slam the PI and keep the power section clean to have the extra thump AND somewhat of a classic cranked tone.

I see nothing pedantic or trivial about trying to help someone better understand how an amp works.....i'm an intellectual, i deal in specifics not general terms......it's just the way i roll i guess.

 

[MrMarkIII]

You can "slam" the PI all you want, but if the Master volume is on "2", you're not going to get power section clipping. The Master and Output knobs control the power tube distortion. The Gain or Channel Volume controls pre-amp distortion. Cranking the Gain will clip the 12AX7 pre-amp tubes (NOT the PI, by the way, it's not designed for that), and will certainly affect the signal going to the power tubes, but won't cause the power section to clip like cranking the Master will.
The whole point of a Master Volume is to get tube clipping at low sound pressure levels. This specific clipping occurs in the pre-amp, not the power amp.
It's arguably true that tube amps sound better when the power section is cooking nicely. This happens, however, at high sound pressure levels, not necessarily a bad thing.

 

[YellowJacket]

You can "slam" the PI all you want, but if the Master volume is on "2", you're not going to get power section clipping. The Master and Output knobs control the power tube distortion. The Gain or Channel Volume controls pre-amp distortion. Cranking the Gain will clip the 12AX7 pre-amp tubes (NOT the PI, by the way, it's not designed for that), and will certainly affect the signal going to the power tubes, but won't cause the power section to clip like cranking the Master will.
The whole point of a Master Volume is to get tube clipping at low sound pressure levels. This specific clipping occurs in the pre-amp, not the power amp.
It's arguably true that tube amps sound better when the power section is cooking nicely. This happens, however, at high sound pressure levels, not necessarily a bad thing.

That is what I was thinking. Two volume knobs, one for each channel and one for the overall amp level. The purpose of the gain knob was originally to boost the input level if it was too low. They just kept on turning it up more and more.
See, I follow what Cleekster is saying but I think that we need to get a schematic in here along with an explanation of the circuit from Mesa before we get anywhere with the discussion, otherwise everything is idle speculation. I personally refuse to postulate over details without cold, hard facts hence my comment about pedantry in my earlier post.

Bottom line, you need to run an amp loud to work the power section. If you don't like that, rip out two tubes from your head. If you still don't like that, get yellow jackets. If you don't want to do that to a Recto, buy a Mark V. (the 100, 50, 10watt switch is such an awesome selling point. I wonder what a Mark V would sound like with a Gibson LP and a cab with greenbacks?)

 

[Cleekster]

You can "slam" the PI all you want, but if the Master volume is on "2", you're not going to get power section clipping. The Master and Output knobs control the power tube distortion. The Gain or Channel Volume controls pre-amp distortion. Cranking the Gain will clip the 12AX7 pre-amp tubes (NOT the PI, by the way, it's not designed for that), and will certainly affect the signal going to the power tubes, but won't cause the power section to clip like cranking the Master will.
The whole point of a Master Volume is to get tube clipping at low sound pressure levels. This specific clipping occurs in the pre-amp, not the power amp.
It's arguably true that tube amps sound better when the power section is cooking nicely. This happens, however, at high sound pressure levels, not necessarily a bad thing.

That is what I was thinking. Two volume knobs, one for each channel and one for the overall amp level. The purpose of the gain knob was originally to boost the input level if it was too low. They just kept on turning it up more and more.
See, I follow what Cleekster is saying but I think that we need to get a schematic in here along with an explanation of the circuit from Mesa before we get anywhere with the discussion, otherwise everything is idle speculation. I personally refuse to postulate over details without cold, hard facts hence my comment about pedantry in my earlier post.

Bottom line, you need to run an amp loud to work the power section. If you don't like that, rip out two tubes from your head. If you still don't like that, get yellow jackets. If you don't want to do that to a Recto, buy a Mark V. (the 100, 50, 10watt switch is such an awesome selling point. I wonder what a Mark V would sound like with a Gibson LP and a cab with greenbacks?)

Let me clarify something i am NOT idly speculating...allow me to explain:

about 6 months ago i had power tubes that were going bad and i knew i was going to have to play shows before i got new ones so instead of plugging into my line 6 normally i decided to to take the preamp out(FX send) on my mesa into the Aux. in(power amp in) on my line 6 so the power amp on my mesa is TOTALLY out of the loop so to speak(output and solo all the way down....)

I found that when i got the master knob fairly high the sound became more distorted and had more of a cranked amp sound.......Myles Rose(of groove Tubes)has said repeatedly that the PI is the most overworked, underappreciated tube in your amp and that it is responsible for about 70% of your cranked tone and based on my own experience i'm in total agreement. Honestly when running my amp with the master knob on "2"(w/ the output cranked) it just isn't the same for me as cranking both.....

so i'll say it one more time the master is a PRE-PIMV(controls how much signal hits the PI) and the output is a POST-PIMV(controls how much signal hits the power tubes)

The PI was primarily designed to split the signal but a tube is a tube and when you feed it enough signal it WILL DISTORT.

If you don't believe me that's cool i totally understand as i'm not an amp designer but you don't have to be to hear the difference

turn your gain knob down to 8:30 with the master and output @ 9:00
play
now turn the master up to 2:00(5:30 if using the clean/pushed mode) and play

the difference is obvious IMHO.

 

[YellowJacket]

Let me clarify something i am NOT idly speculating...allow me to explain:

about 6 months ago i had power tubes that were going bad and i knew i was going to have to play shows before i got new ones so instead of plugging into my line 6 normally i decided to to take the preamp out(FX send) on my mesa into the Aux. in(power amp in) on my line 6 so the power amp on my mesa is TOTALLY out of the loop so to speak(output and solo all the way down....)

I found that when i got the master knob fairly high the sound became more distorted and had more of a cranked amp sound.......Myles Rose(of groove Tubes)has said repeatedly that the PI is the most overworked, underappreciated tube in your amp and that it is responsible for about 70% of your cranked tone and based on my own experience i'm in total agreement. Honestly when running my amp with the master knob on "2"(w/ the output cranked) it just isn't the same for me as cranking both.....

so i'll say it one more time the master is a PRE-PIMV(controls how much signal hits the PI) and the output is a POST-PIMV(controls how much signal hits the power tubes)

The PI was primarily designed to split the signal but a tube is a tube and when you feed it enough signal it WILL DISTORT.

If you don't believe me that's cool i totally understand as i'm not an amp designer but you don't have to be to hear the difference

turn your gain knob down to 8:30 with the master and output @ 9:00
play
now turn the master up to 2:00(5:30 if using the clean/pushed mode) and play

the difference is obvious IMHO.

Well, that is a more clear explanation but it doesn't detract from the fact that you have to crank everything to get a good sound.

Still, Perhaps this sheds some light onto why the three channel rectifiers don't sound as good a low volumes as the old ones do. My two channel doesn't have two volume knobs in each signal chain, there is only one unless I activate the effects loop and adjust the loop master volume. I suppose I could throw a patch cable through there and play with it that way but it seems kind of pointless.

 

[Cleekster]

Let me clarify something i am NOT idly speculating...allow me to explain:

about 6 months ago i had power tubes that were going bad and i knew i was going to have to play shows before i got new ones so instead of plugging into my line 6 normally i decided to to take the preamp out(FX send) on my mesa into the Aux. in(power amp in) on my line 6 so the power amp on my mesa is TOTALLY out of the loop so to speak(output and solo all the way down....)

I found that when i got the master knob fairly high the sound became more distorted and had more of a cranked amp sound.......Myles Rose(of groove Tubes)has said repeatedly that the PI is the most overworked, underappreciated tube in your amp and that it is responsible for about 70% of your cranked tone and based on my own experience i'm in total agreement. Honestly when running my amp with the master knob on "2"(w/ the output cranked) it just isn't the same for me as cranking both.....

so i'll say it one more time the master is a PRE-PIMV(controls how much signal hits the PI) and the output is a POST-PIMV(controls how much signal hits the power tubes)

The PI was primarily designed to split the signal but a tube is a tube and when you feed it enough signal it WILL DISTORT.

If you don't believe me that's cool i totally understand as i'm not an amp designer but you don't have to be to hear the difference

turn your gain knob down to 8:30 with the master and output @ 9:00
play
now turn the master up to 2:00(5:30 if using the clean/pushed mode) and play

the difference is obvious IMHO.

Well, that is a more clear explanation but it doesn't detract from the fact that you have to crank everything to get a good sound.

Still, Perhaps this sheds some light onto why the three channel rectifiers don't sound as good a low volumes as the old ones do. My two channel doesn't have two volume knobs in each signal chain, there is only one unless I activate the effects loop and adjust the loop master volume. I suppose I could throw a patch cable through there and play with it that way but it seems kind of pointless.

I agree with you in that cranking the master and output does get the best sound provided you aren't running very much front end gain. what i was trying to get at though is if you have 2 volumes a good comprimise is to run the channel volume high and the global low as opposed to the reverse which seems to be the norm with recto guys. i think that the old rectos and new ones are mean't to serve a different purpose...... when they started to design the recto in the late 80's hair metal reigned supreme and the Soldano stuff was highly sought after and so mesa made thier own version of a SLO-100 and ended up with the amp Soldano should've made but didn't. an amp with a fat creamy midrange for those shred solos.when the later 3 channel came out nobody played any solos but where trying to get that scooped mid metal sound so mesa made some adjustments and gave guitarists what they wanted....this of course is just my opinion of course but i know when i play my line6 modeler i prefer the recto model based on the '94 TremoVerb especially for solos.