Less Gain For Lead Channel?

[Direwolf]

Hey guys. I've got a question here about a Mk III Blue Stripe that has been modded to a III+. I'm not a metal player so I've been wondering what mods I can do to reduce the amount of gain in my lead channel. I know there's the obvious "turn the gain knob down" answer but I find the tone diminishes when I do this. I've tried a lower gain tube in V3 but it really starts taking away from the bottom end and overall tone response. I know the blue stripe is said to have the most gain but buying a new amp just isn't an option at this point. So my question is this. What can I do to the circuit in the lead channel to reduce the amount of drive? I really love this amp and the tone it produces. I just want less gain. Any thoughts and ideas are greatly appreciated!

 

[Heritage Softail]

I have a IIC, and backing off the treble lowers the gain. Not sure if we are talking the same thing here, but I like less or rather just barely enough gain and more volume, to get the smooth heat moved more from the power section than the preamp. It seems more dynamic and better note clarity.

III+ - Nice

.

 

[daveg62]

you could try a 12at7 in the v5 spot. I prefer my blue stripe with a bit less gain also.

 

[screamingdaisy]

I know there's the obvious "turn the gain knob down" answer but I find the tone diminishes when I do this.

The human brain is hardwired to notice changes. If you lower the gain and it registers a drop in bass your brain will pay more attention to the change in bass than the midrange quality.

This problem is exacerbated by the Mark style preamp since the tone controls are before most of the gain stages.... thus lowering or raising the gain knob also changes the EQ of the amp.

The way to get around this is to avoid doing direct comparisons. Try lowering the gain to where you think you might like it before even turning the amp on, then power up the amp and adjust the EQ to suit the new gain setting. Avoid reverting back to the higher gain setting since that'll trigger the brain to notice changes again, in which case it'll hear the increase in bottom end and tell you that things are sounding fuller without paying attention to any of the other details.

 

[Direwolf]

Thanks for the response guys. My current settings are
Volume 1 - 7 (pulled)
Treble - 5 (pulled)
Bass - 4 (pulled)
Middle - 6 1/2
Master - 3
Lead Gain - 2 (with a 12au7 I set it at 6)
Lead Master - 3
Presence - 2-3

I have tried a lower gain in V1 also but I like a 12AX7 here better. I've also got a really nice NOS Mullard 12AT7 in the P.I. I should've asked Mesa to do a mod on it when I sent it to them for some repairs and filter cap replacement. Honestly, I was kind of overwhelmed when Mike called me to ask a few questions about it and forgot. Thanks again for the thoughts.

 

[daveg62]

really hard for us to understand what tone you are going for. We all have that sound in our head we try to find. The way I see it your options include tube replacements, tone stack adjustments, speakers, and maybe even trowing an eq in the loop. I know my amp can sound and feel totally different depending on the tube brand and type that I use. Maybe a darker sounding v1 tube might be what your after. I don't have the III+ mod on mine and I'm not sure what that is. Does the mod add more gain?

 

[SonVolt]

Hey a fellow Noogan... Howdy. I was born and raised right outside Chattanooga in Ooltewah. I miss that city. Beautiful place.

 

[JOEY B.]

JAN GE 5751 in V3. Maybe lower the presence a bit? Beyond that it will be a speaker change.

 

[SonicProvocateur]

Play on R2 with Volume 1 on 5 and the treble on 7. Pull treble and bass and adjust presence and Master volume to taste.

My R2 is pretty **** hot on my blue stripe with 12ax7s in all the slots adjusted for metal, and playing on R2 gets me anywhere from a sweeeet Clean Marshall sound, to an overdriven Marshall sound, the Dumble sound, to a red hot Marshall sound and close to cloning the Lead tone.

 

[chipaudette]

Thanks for the response guys. My current settings are
Volume 1 - 7 (pulled)
Treble - 5 (pulled)
Bass - 4 (pulled)
Middle - 6 1/2
Master - 3
Lead Gain - 2 (with a 12au7 I set it at 6)
Lead Master - 3
Presence - 2-3

I don't have a Mark III, but I have a Mark IIC that was upgraded to a IIC+. Looking at your knob settings, you've got your Treb/Bass/Mid set for a pretty thick lead setting. With the treble pulled and with that much bass and mids, you're gonna get some really substantial saturation, even at low "lead gain" settings. It sounds like that's not what you want.

If by "less gain" you mean "less saturation", the first thing that I'd try is pushing your treble knob back in. Then, because your tone now be too muddy, you've got to back off on the Bass and the Mids to compensate a bit. I'd try something like:

Treble: 3-4 (pushed)
Bass: 0-2 (pushed)...this is a very sensitive region on my amp. 0,1,or 2 are all very different.
Mids: 3-4

Dial Vol 1 to taste (6-10) and Lead Gain to taste (~2-3). With the T/B/M knobs way down like this, don't be afraid to try that Vol1 = 10 setting. That's how I run it. With Lead Gain down to 2, it's a nice and loose touch-sensitive sound.

Then, be sure to have your lead bright pulled. Yes, that'll bring in a little more gain, but the gain is the higher frequencies, so (IMO) it adds a nice crisp bite to the attack at these gain levels but doesn't give you the excessive sustain that it looks like your trying to avoid.

Since you talk about missing bass when at low gain, you should (as I'm sure you know) get your bass back up by using the graphic EQ and not with the Bass knob itself. When I'm running these kinds of knob settings, I put all my sliders in the the middle and then I:

Low: half-way to max
Low-mid: stay in the middle
Mid: half-way to min
High-Mid: Half-way to max
High: To taste depending upon the presence. Mine stays in the middle.

If you still don't have enough bass, I would offer that you consider traditional rock guitar notion that the bass is supposed to come from the bass guitar player and not the guitar player. The mix is usually better if you leave the bass to him.

To me, the key to a looser gain with less saturation is pushing in that treble knob. If you haven't tried that in a while, push it in and then experiment with the other knobs.

Chip

 

[Direwolf]

Thanks again for the response guys. I really appreciate it. Tones I'm hunting are early Santana meets Larry Carlton meets mid 70's Garcia with a hint of Trey Anastasio. I know. It's weird.

Looking at your knob settings, you've got your Treb/Bass/Mid set for a pretty thick lead setting. With the treble pulled and with that much bass and mids, you're gonna get some really substantial saturation, even at low "lead gain" settings. It sounds like that's not what you want.

Chip believe it or not there isn't as much bass on the lead channel as it seems. I've always read where guys never turn their bass up past 2 but for some reason my knob doesn't seem to react until about 3. Not sure if it's a bad spot in the pot or not. Mesa never said anything to me about the pots so I'm assuming they are ok. You are correct about the saturation. I'm not looking necessarily for extreme saturation. I do however like the sustain. I'll definitely try pushing the treble in. I just liked the upper mid harmonics it produces. I really appreciate everyone taking the time to weigh in on this. I'll be busy in the mad scientists tone lab today for sure.

 

[Direwolf]

I guess I should elaborate on the tone references. I like certain aspects of these players tones. I'm not necessarily trying to copy their style or sound. Just parts of it. I love Santana's sustain and mid range. Larry Carlton's smooth sound is unprecedented in my book. As for the Jerry Garcia tone I like his clarity and bell like tone he had in the mid 70's to early 80's. While I know he doesn't rank very high on most players list as a player, to me his tone has always been great. This brings us to Trey Anastasio. I'm referring to his most recent tone. He has gone back to using his Mk III red stripe and he gets this really nice vocal mid range thing going on with it. I know this is kind of a mixed bag of tones and hopefully I'm not chasing the white dragon in this quest but the one thing that all these players share in common are Mesa Mk amps. So I feel it's possible. My style is a cross between blues/fusion/jam. Thanks again for the help guys. I'm off to the lab!!

 

[Trey Blue]

I have volume 1 set to 10. But I also use two tube screamers - one with the gain on zero, the other on 10. If I want a nice clean sound I just back off my guitar volume a bit and the with the two pedals I have such a range that I can get any type of gain I want (turn on both tube screamers, lead, and R2 for ludicrous speed).

 

[Boogiebabies]

Does it have a 1000pf/.001uf capacitor across the (V3) second lead stage 270K plate resistor ?

 

[chipaudette]

Hey Boogiebabies,

Good to see you around!

I think that the OP has a III+. Isn't that 1000pF cap the heart of the III+ mod? If MikeB doesn't do that, what does he do?

Chip

 

[Boogiebabies]

Hey Boogiebabies,

Good to see you around!

I think that the OP has a III+. Isn't that 1000pF cap the heart of the III+ mod? If MikeB doesn't do that, what does he do?

Chip

On the ++'s I have seen they have the 20pf and two 3.3M resistors in paralell for the circuit to the lead input and output, a 1000pf cap across the second lead stage plate resistor and the .02 cap that feeds the 680K resistor to the lead input (.02 not on schematic, but it's in the middle of the board) is removed and wired directly to the 680K lead input.

 

[Direwolf]

BB I'm assuming you're referring to C30? If so then no. I split the difference and went with a 500pf. For whatever reason, and this may be a misconception, I find the 1000pf cap adds compression to the lead gain. I do use a TS-9 to add sustain to the lead channel. The gain on the TS is set to minimum with the volume set at 1:30. For a while I had no cap in C30. I preferred the "open" sound that it produced but it also introduced a lot of unwanted sizzle.

Chip I did take your advice on the tone stack settings and this did help a bunch. Not sure if I took a mental leave of absence or not in forgetting how much influence the tone stack has on these amps.

Thanks again guys for all the advice!

 

[chipaudette]

You went 500pf, huh? Very interesting.

Again, I don't have a Mark III, but on my IIC->IIC+, I modded the amp to made this cap switchable so that I could try different values. Prior to my mod, I actually felt that my IIC+ was a little too smooth. I wanted more sizzle.

So, I opened her up, lifted up one leg of the cap, stuck in a little wiring, and a on-off-on switch in place of the Slave knob. With this switch, I can use the original 1000pF that MikeB put in, or I can switch to a 500 pF (or is it 1000 || 500 = 333pF, I can't remember), or I can switch to no cap at all (which is the stock Mark III, I think). Unless I'm specifically going for Metallica AJFA, the "no cap" setting is too buzzy for my tastes. The 1000pF setting is good, but a little too smooth/muffled some times. Most of the time (low gain, mid gain, or non-Metallica high gain), I find myself on the 500 pF (or 333pF) setting.

Of course, I believe that the Mark III is generally considered to be much brighter / buzzy than the IIC+...even beyond just the effect of this cap. So, with its inherently brighter sound, maybe I would have prefered the 1000pF in the Mark III. But, maybe not. I'm thinking that your 500 pF is probably a good call. It certainly gets you far away (in a good way?) from the stock configuration that has no cap at all.

Chip

 

[Boogiebabies]

You have to admit there are a ton of ceramic disc caps in the "famous" Boogie lead channel.
This no doubt has some effect, but it also has a ton to do with how the gain is structured.

My memory of an actual MK III is fuzzy. Maybe we should compare it to a IIC+. It seems on the III schematic that it should be less bright than a IIC+, but no MK III I have come across is as smooth in the overdrive. If you/anyone has a pic I am curious if there is a 180pf off the grid of V3A to the cathode or ground.

 

[Direwolf]

I'll try to get into my amp and take a pic tomorrow. I have to admit, ever since I got my III+ there has been this little voice in the back of my mind saying "you really should just get a IIC+ and stop messing around". :idea: