Model of the Mesa Boogie Mark series on-board graphic eq

Model of the Mesa Boogie Mark series on-board graphic eq


  • Total voters
    41

shredi knight

Power User
MesaEQ2avatarxxx2.jpg





I think an accurate model of the Mesa on-board graphic eq is the one thing missing in Mark style amps in the Axe FX - USA (clean, RHY 1&2, Lead 1&2, IIC+ 1&2) and FAS Lead 1&2 (which are based on Mesa Mark amps). Most any Mark amp owner will tell you that the on-board eq is essential in getting the classic Mesa Mark tone.

Even if you can get close with one of the Axe FX's current eq blocks (I currently use the Parametric eq), an essential part of how the on-board graphic eq works and sounds is that it falls in between the preamp & power amp sections of the real world amps, which currently isn't possible to do with the current amp models on the Axe FX (you either have to put an eq before or after the amp block).

The eq would either need to be "built in" between the preamp & power amp sections the Axe FX's Mark style amps, or as a stand alone block that can be placed between the preamp & power amp sections of the amp blocks.

What do you think?
 
I'm voting yes, unless Cliff says something more definitive.

Cause if Cliff says it can be done with what's in the box, then I'm happy.
 
Parametric EQ. It's got five bands, frequencies are on that picture you have there. Just have to figure out what the Q's are on the real one. I think the default of the Q will be in the ballpark already.
 
Dutch said:
Parametric EQ. It's got five bands, frequencies are on that picture you have there. Just have to figure out what the Q's are on the real one. I think the default of the Q will be in the ballpark already.

The frequencies in the pic are said to be not the actual ones that the sliders are tuned to. I've seen 2 or 3 analysis of what they actually are, and they have all said something different. There's also no definitive answer to what the correct Qs are. Those things aside for the moment, there's still not a way to put the parametric eq in between the pre & power amp sections of the amp block where it should be placed.
 
I think fellow forumer schnarf figured out/calculated the Q and frequency values. Maybe he joins the discussion.
There are patches of him up on axechange, e.g. his Mk IIC+ patch, where everyone interested can get the settings from the paraEQ block.

Honestly I've no idea if it makes that big difference to put an EQ after the amp block or in between preamp and power amp (which currently is not possible). Facts, anyone? I'm aware of the logical difference (EQ would be before power amp distortion), but how dramatic would be this difference?

Of course, if Cliff sais "No problem, I'll add it because it's possible and can't be achieved with the EQ blocks at the moment", I'll enjoy when he would add that feature.
But I won't have sleepless nights if that won't happen.
 
Honestly I think this would be a cool feature to have on every amp.

If Cliff could put a Mark Series type 5 band EQ, (and an on/off switch) in the amp block, I think it would rock.
 
Guitar-Tiz said:
Honestly I think this would be a cool feature to have on every amp.

If Cliff could put a Mark Series type 5 band EQ, (and an on/off switch) in the amp block, I think it would rock.

Best case scenario would be for it to be included in all the amp sims. It could be in the amp block's advanced menu under something like "Pre Pwr Amp EQ" or "Post Pre Amp EQ" (though those sound a little confusing :mrgreen: ), where you could choose the type of eq: "Graphic", "Parametric", "USA". "Graphic and "Parametric" being the same as the ones in the blocks, and "USA" being the Mesa.
 
shredi knight said:
[quote="Guitar-Tiz":pyrpvh45]Honestly I think this would be a cool feature to have on every amp.

If Cliff could put a Mark Series type 5 band EQ, (and an on/off switch) in the amp block, I think it would rock.

Best case scenario would be for it to be included in all the amp sims. It could be in the amp block's advanced menu under something like "Pre Pwr Amp EQ" or "Post Pre Amp EQ" (though those sound a little confusing :mrgreen: ), where you could choose the type of eq: "Graphic", "Parametric", "USA". "Graphic and "Parametric" being the same as the ones in the blocks, and "USA" being the Mesa.[/quote:pyrpvh45]

For ease of understanding, how about just name it "USA EQ" and then give, Graph, Para, USA, and OFF, as types. ;)

EDIT: Honestly, I don't think we'd really need the "USA" EQ variation, as this can be achieved using the current ParaEQ, which would be easier to adjust to personal taste anyway.

However if Cliff puts in a USA variation, then I'm going to argue. :p
 
Guitar-Tiz said:
EDIT: Honestly, I don't think we'd really need the "USA" EQ variation, as this can be achieved using the current ParaEQ, which would be easier to adjust to personal taste anyway.

However if Cliff puts in a USA variation, then I'm going to argue. :p

I would like an exact replica of the Mesa eq, with the correct frequencies, Qs, + and - dB range of the sliders, with the sliders travel behavior and interaction modeled as well.
 
shredi knight said:
[quote="Guitar-Tiz":10yzln2f]

EDIT: Honestly, I don't think we'd really need the "USA" EQ variation, as this can be achieved using the current ParaEQ, which would be easier to adjust to personal taste anyway.

However if Cliff puts in a USA variation, then I'm going to argue. :p

I would like an exact replica of the Mesa eq, with the correct frequencies, Qs, +&- dB range of the sliders, with the sliders travel behavior and interaction modeled as well.[/quote:10yzln2f]

And if Cliff says, "It can be perfectly replicated in the PEQ..."? :|

I know what your saying though.
 
Isn't there an analysis of the Mesa EQ on the Wiki ?

Wait...here it is:

'Analysis of a Mesa/Boogie Mark IV schematic revealed the following settings for recreating the famous amp's graphic EQ.'

Frequencies:

* 87.61 Hz
* 371.74 Hz
* 723.43 Hz
* 1575.87 Hz
* 4822.88 Hz

Q:

* 1.414 (ideal for octave equalizer)
* 1.3 (actual, due to component values used)

'There's about 18dB of cut and 17dB of boost. This is in the ideal world, so +/- 15dB was probably the design goal. The pot response is logarithmic – i.e. most of the cut/boost is near the end of the pot travel. Also, this is not a constant Q design, so the Q decreases (or bandwidth increases) with less boost or cut. I don't know if Cliff's graphic is constant Q, but the parametric should be constant Q, given you have a Q setting.'
 
To be honest, at first I was a bit miffed about the USA models not having the graphic EQ somewhere in there, but now that I've had the Axe for a bit I don't really care. I just have a PEQ behind the amp block and EQ what I want, roughly around those Mesa 5-band areas. Maybe my figures aren't 100% spot on for whatever a real Mesa 5-band does (assuming they're all consistent), but I get the tone I want in the end regardless and that's what counts. I guess I'm not so worried about it being a 100% accurate Mark series tone, more just whether or not I can get the tone I want.

To be honest, I often found the EQ on my Mark III and Quad somewhat limiting. I'd be hearing some frequency I wanted out of there, but just couldn't get to it without adding an EQ in the loop. No problem with the Axe. :cool:
 
Use the Parametric or Graphic EQ. FWIW, the EQ in the Mark series sucks. It's a crude, clunky and limited design. The EQ in the Axe-Fx is far superior and much more flexible.

If you need to, you can copy the Mesa EQ using the Parametric EQ block.
 
FractalAudio said:
FWIW, the EQ in the Mark series sucks. It's a crude, clunky and limited design. The EQ in the Axe-Fx is far superior and much more flexible.

+1

Personally, I think it's sorta just a convenience and necessity thing. The Marks really need that EQ, unless your goal is to sound like Santana, and that EQ happens to be on board (most of the time). So people get used to and attached to it, and think it's some kind of magical EQ.

As I said though, I often found it quite limiting. It's only 5 bands, fix Q, fixed bands, fixed range. You can, IMO, do the same thing and more with the Axe-FX's EQs. Normally I run just one PEQ behind the amp block and I'm getting the same kinds of tones and better than I used to get with my Mark III and Quad. I posted up a AJFA-style tone on a To Live Is To Die clip on HCAF, and for the uber mid scoop on that I used the same PEQ (adjusted the gains obviously), and then added another behind it to attack the 750Hz area even more as well as some other freqs. I'd have to be using an additional EQ unit to be able to do that with my real Mesa stuff.
 
FractalAudio said:
Use the Parametric or Graphic EQ. FWIW, the EQ in the Mark series sucks. It's a crude, clunky and limited design. The EQ in the Axe-Fx is far superior and much more flexible.

If you need to, you can copy the Mesa EQ using the Parametric EQ block.

So does that mean it doesn't matter that it's not in between the preamp, and power amp?
 
FractalAudio said:
Use the Parametric or Graphic EQ. FWIW, the EQ in the Mark series sucks. It's a crude, clunky and limited design. The EQ in the Axe-Fx is far superior and much more flexible.

:mrgreen: hehe, somehow I'm not surprised by this answer...

+1 on Guitar-Tiz's question. It's not that important for me, but I'm curious and would like to know.
 
Sebastian said:
FractalAudio said:
Use the Parametric or Graphic EQ. FWIW, the EQ in the Mark series sucks. It's a crude, clunky and limited design. The EQ in the Axe-Fx is far superior and much more flexible.

:mrgreen: hehe, somehow I'm not surprised by this answer...

+1 on Guitar-Tiz's question. It's not that important for me, but I'm curious and would like to know.

The only reason I wonder is, if it does make a difference, then wouldn't it be nice to be able to put ANY block between the preamp, and poweramp?

If that's the case, then maybe what we need is a way to put in some sort of FXloop, for the ampblocks?

Maybe link it to an "amp- loop-in block", and an "amp-loop-out block" for each amp block?

Drop in the loop-out-1, a bunch of FX, and then the loop-in-1, go into ampblock-1 and turn on the loop, and bingo!

It would be a great place for Reverbs, and EQ's at the least.

Then again if it doesn't make a difference, then it's moot, now isn't it... :D
 
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