Marshall vs. Mesa/Symmetrical vs. Asymmetrical (clipping)???

[Sixtonoize]

No...if anything, a Marshall has more symmetrical clipping than a Mesa (assuming that you're talking about a Dual Rec) because a Dual Rec gets most of its distortion from a cold clipping stage which only clips one side of the waveform.

Again, assuming that you're comparing a Recto to a JCM-style amp, I'm willing to bet that the tonal difference that you're noticing is more caused by the voicing of the gain stages - the Mesa will push a lot of bass through the gain stages whereas the Marshall is more mid-focused. Clipping different frequency ranges causes a significant difference in the tone and feel of the amp.

Sorry to be possibly detracting from the thread- but would the Mark series Mesa/Boogie amps have more asymmetrical clipping compared to a JCM-style Marshall?

I don't believe so. The Mark series doesn't use a Cold Clipping stage like the Rectifier series.
It uses 5 regular gain stages and gets its tone (primarily) from the pre-gain tone stack...but all of the clipping stages are just regular gain stages with varying degrees of filtering applied to each.

 

[Shask]

Yeah, the Mark series basically has several stages cascaded together that are set up pretty similar, ie, lots of gain, and a good amount of bass.

Thats why they have a more clear, less saturated tone going on, than say a Recto or 5150.

 

[Death by Uberschall]

So are we saying by changing this one resister we can have less fizzy, smoother Recto tones?

 

[wIsEbLooD]

Yep. Throw a 10k in there and it will clear it up.

did it to a soldano and it got smoother and more gain/saturation.

 

[Sixtonoize]

One resistor change, if it's the right value and in the right position, can make all the difference in the world.

 

[ericsabbath]

Yep. Throw a 10k in there and it will clear it up.

did it to a soldano and it got smoother and more gain/saturation.

that's not enough for a recto
actually, it gets fizzier

it needs some treble leaking and more mid focusing between the first stages

 

[petejt]

No...if anything, a Marshall has more symmetrical clipping than a Mesa (assuming that you're talking about a Dual Rec) because a Dual Rec gets most of its distortion from a cold clipping stage which only clips one side of the waveform.

Again, assuming that you're comparing a Recto to a JCM-style amp, I'm willing to bet that the tonal difference that you're noticing is more caused by the voicing of the gain stages - the Mesa will push a lot of bass through the gain stages whereas the Marshall is more mid-focused. Clipping different frequency ranges causes a significant difference in the tone and feel of the amp.

Sorry to be possibly detracting from the thread- but would the Mark series Mesa/Boogie amps have more asymmetrical clipping compared to a JCM-style Marshall?

I don't believe so. The Mark series doesn't use a Cold Clipping stage like the Rectifier series.
It uses 5 regular gain stages and gets its tone (primarily) from the pre-gain tone stack...but all of the clipping stages are just regular gain stages with varying degrees of filtering applied to each.

Oh ok then. Thanks Sixtonoise & Shask.

I'm just wondering now about the "Lead Gain" and "Lead Drive" controls. I noticed that they impart different characteristics to the overall tone.

 

[Shask]

Yep. Throw a 10k in there and it will clear it up.

did it to a soldano and it got smoother and more gain/saturation.

that's not enough for a recto
actually, it gets fizzier

it needs some treble leaking and more mid focusing between the first stages

Yeah, I would be surprised if that one resistor did it a lone. I am sure it would be less fuzzy, but you would need to change other things to make it a clearer, Mark series type tone.

But, then again, I haven't tried it

 

[Shask]

No...if anything, a Marshall has more symmetrical clipping than a Mesa (assuming that you're talking about a Dual Rec) because a Dual Rec gets most of its distortion from a cold clipping stage which only clips one side of the waveform.

Again, assuming that you're comparing a Recto to a JCM-style amp, I'm willing to bet that the tonal difference that you're noticing is more caused by the voicing of the gain stages - the Mesa will push a lot of bass through the gain stages whereas the Marshall is more mid-focused. Clipping different frequency ranges causes a significant difference in the tone and feel of the amp.

Sorry to be possibly detracting from the thread- but would the Mark series Mesa/Boogie amps have more asymmetrical clipping compared to a JCM-style Marshall?

I don't believe so. The Mark series doesn't use a Cold Clipping stage like the Rectifier series.
It uses 5 regular gain stages and gets its tone (primarily) from the pre-gain tone stack...but all of the clipping stages are just regular gain stages with varying degrees of filtering applied to each.

Oh ok then. Thanks Sixtonoise & Shask.

I'm just wondering now about the "Lead Gain" and "Lead Drive" controls. I noticed that they impart different characteristics to the overall tone.

The main volume knob determines how much signal gets fed into the the front end. (Which includes the other channels as well). The lead drive is cranking up the signal just in the lead gain stages. I think it is stage 3 and 4 from memory.

So, basically the volume is the "gain" control of the signal going into all 5 stages, and the Lead Drive is basically the "gain" of the last 2 gain stages.

(Thats not 100% technically correct, but enough for understanding of the position of those 2 controls within the circuit).

 

[petejt]

Cheers Shask.


Yep- the level of the Lead Gain will determine how much "gain on tap" is available at the Lead Drive.


Sucks at the moment because my MarkIV is in storage...

 

[JakeAC5253]

Shask, you seem to know Rectos pretty well. I am curious the exact technical function of the 'Output' knob.

 

[Sixtonoize]

The exact technical function: A voltage divider.
The colloquial guitarist meaning: It's a master volume.

 

[TheMagicEight]

I know I'm digging this one out of the grave here, but I'm finding it very interesting how much similarity there is between the Marks and the 20th Anniv. Ecstasy in terms of gain structure.

 

[JakeAC5253]

I know I'm digging this one out of the grave here, but I'm finding it very interesting how much similarity there is between the Marks and the 20th Anniv. Ecstasy in terms of gain structure.

Cool. Any details?

 

[TheMagicEight]

I know I'm digging this one out of the grave here, but I'm finding it very interesting how much similarity there is between the Marks and the 20th Anniv. Ecstasy in terms of gain structure.

Cool. Any details?

Neither use a cold biased distortion stage. The 101b and 100b XTCs do on the Red channel, but this new Ecstasy is certainly unlike the others in that it's a fairly new design and has every stage warm-biased.

The Mark series is a different amp for sure, but crank up the TMB controls and you're getting much closer to the Ecstasy feel. Use the graphic EQ to shape your overall sound, and you can get a similar thing going. Of course, they're still different beasts, and I prefer the Mark series' tone due to its output section (the XTC puts about 525VDC on the power tube plates - far too much for a warm biased gain section IMO). The Ecstasy is the better package deal though. Just enough of the right features and switching to make a perfect amp. Mesa? Far too many options.

 

[JakeAC5253]

I know I'm digging this one out of the grave here, but I'm finding it very interesting how much similarity there is between the Marks and the 20th Anniv. Ecstasy in terms of gain structure.

Cool. Any details?

Neither use a cold biased distortion stage. The 101b and 100b XTCs do on the Red channel, but this new Ecstasy is certainly unlike the others in that it's a fairly new design and has every stage warm-biased.

The Mark series is a different amp for sure, but crank up the TMB controls and you're getting much closer to the Ecstasy feel. Use the graphic EQ to shape your overall sound, and you can get a similar thing going. Of course, they're still different beasts, and I prefer the Mark series' tone due to its output section (the XTC puts about 525VDC on the power tube plates - far too much for a warm biased gain section IMO). The Ecstasy is the better package deal though. Just enough of the right features and switching to make a perfect amp. Mesa? Far too many options.

Sounds very cool. When you say to crank the TMB on the Mark to get close to the newer XTC sound, do you mean with the sliders engaged, or disengaged?

Thanks for the analysis