Mark IIC+ Tips

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There's been a lot of complaining about the Mark IIC+ models. So I begrudgingly dragged the amp out of storage today (as it weighs a metric ton) and repeated the measurements and did some A/B tests. As expected the models are extremely accurate.

That being said it is a bear to dial in. Here are some tips:

1. The old version of the model incorrectly referenced the Mark IV tone stack. These tone stacks are identical except for the taper of the mid pot. The IIC+ has a linear pot and the Mark IV has a Log10 pot. I had it backwards in my earlier comments. My guess is that Mesa found that turning the midrange down sounds best (and it does) so they changed the pot taper to do this automatically since noon on a Log10 pot is equal to a 1.0 on a linear pot.

2. Commensurate with (1) I found myself turning the midrange down as well as the bass and turning the treble up.

3. I think the default Master Volume value is a bit high so you may want to turn that down. I've reduced the default for Quantum 2.03.

4. Turn the bright switch on. Every bit of information I've found says that people typically used the Pull Bright on the Volume knob. This is equivalent to the Bright switch under the Treble control on the model. I always turn it on and I've set it on by default for Q2.03.

5. USE THE EQ. The tone stack is pre-distortion which is atypical for a high-gain amp. Tone stacks are almost always post-distortion. Since the tone stack is pre-distortion you need to do your post distortion tone shaping using the EQ. The tone controls set the feel and the distortion texture, the EQ shapes the final tone. I like to do a gentle V-curve.

These were my settings for a killer high-gain tone:
Model: USA IIC+
Input Drive: 8.1
Overdrive: 9-10
Bass: 1.0
Midrange: 1.8
Treble: 8.9
Presence: 4.5
MV: 4.0
Level: -20 dB
Bright Switch ON
80 Hz: 4.8
240 Hz: 2.6
750 Hz: -4.5
2200: -0.2
6600: 0
 
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You posted some tips not that long ago and I've been very happy with the results. It's actually replaced my former go to for lead tones. Thanks!
 
There's been a lot of complaining about the Mark IIC+ models. So I begrudgingly dragged the amp out of storage today (as it weighs a metric ton) and repeated the measurements and did some A/B tests. As expected the models are extremely accurate.

That being said it is a bear to dial in. Here are some tips:

1. The old version of the model incorrectly referenced the Mark IV tone stack. These tone stacks are identical except for the taper of the mid pot. The IIC+ has a linear pot and the Mark IV has a Log10 pot. I had it backwards in my earlier comments. My guess is that Mesa found that turning the midrange down sounds best (and it does) so they changed the pot taper to do this automatically since noon on a Log10 pot is equal to a 1.0 on a linear pot.

2. Commensurate with (1) I found myself turning the midrange down as well as the bass and turning the treble up.

3. I think the default Master Volume value is a bit high so you may want to turn that down. I've reduced the default for Quantum 2.03.

4. Turn the bright switch on. Every bit of information I've found says that people typically used the Pull Bright on the Volume knob. This is equivalent to the Bright switch under the Treble control on the model. I always turn it on and I've set it on by default for Q2.03.

5. USE THE EQ. The tone stack is pre-distortion which is atypical for a high-gain amp. Tone stacks are almost always post-distortion. Since the tone stack is pre-distortion you need to do your post distortion tone shaping using the EQ. The tone controls set the feel and the distortion texture, the EQ shapes the final tone. I like to do a gentle V-curve.

These were my settings for a killer high-gain tone:
Model: USA IIC+
Input Drive: 8.1
Overdrive: 9-10
Bass: 1.0
Midrange: 1.8
Treble: 8.9
Presence: 4.5
MV: 4.0
Level: -20 dB
Bright Switch ON
80 Hz: 4.8
240 Hz: 2.6
750 Hz: -4.5
2200: -0.2
6600: 0

FWIW, I think it's VERY cool that you do crap like this for your customers....definitely above and beyond.

RR
 
I've never had a IIC, but I've had a few Mk IV's and a TOV, all of which have "somewhat" similar tone-stacks. They can be a bear to dial in; pure Nirvana when you get it, but pretty frustrating to get there.

The Tremoverb was somewhat more straightforward, but the Mk IV could really leave you empty sometimes, especially when switching between channels. In fact, now that I think back (and I haven't actually had one for 10-years or so) I'm not sure I ever got the red channel the way I wanted it, twice in a row.

On the other hand, the Mk IV, in particular, can cover a huge territory of soundscapes, and it's easy to see why it was (is?) a very popular hired gun studio player's rig.
 
4. Turn the bright switch on. Every bit of information I've found says that people typically used the Pull Bright on the Volume knob. This is equivalent to the Bright switch under the Treble control on the model. I always turn it on and I've set it on by default for Q2.03.

5. USE THE EQ. The tone stack is pre-distortion which is atypical for a high-gain amp. Tone stacks are almost always post-distortion. Since the tone stack is pre-distortion you need to do your post distortion tone shaping using the EQ. The tone controls set the feel and the distortion texture, the EQ shapes the final tone. I like to do a gentle V-curve.

These were my settings for a killer high-gain tone:
Model: USA IIC+
Input Drive: 8.1
Overdrive: 9-10
Bass: 1.0
Midrange: 1.8
Treble: 8.9
Presence: 4.5
MV: 4.0

Wow, that's almost exactly how I used to set up my IIC+ back in the day, except I don't remember a lot of venues or sound techs that could handle a MV setting of 4. Those things are as loud as they are heavy!

I seem to remember a pull/shift on the treble pot that shifted it's center down a bit and thickened up the tone substantially. Is there a simple way to replicate that?

Gorgeous koa cabinet and cane grill--that was a fabulous amp!
 
Thank you sir, I'm definitely going to try these settings. Looking forward to learning which new amp models are forthcoming!
 
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