I just tried a 5751 preamp tube in V2 and I think it helps out the 2nd channel. I also tried a 12at7, but that dulled the highs a little. the 5751 gives me a better sound, but still retains the highs. I think that the 1st and 3rd channel sound so freakin good, that it just makes it tough for channel 2 to measure up.
Anyone try a 5751 in a MKIV ?
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I think channel 2 will get me to sell the amp/ What a frustrating pain in the arse. I just want a nice crunch, out of channel two, for classic rock rythm. The minute I get the channel to cut with some bite, it stars to get a nasty honk sound going. Push it to much and the mids almost sound like cigital clipping, youck! My marshalls sound so sweet compared to this channel. My Marshalls can't touch 1 and 3 ( I love em) but 2 is getting to me. Must I use the eq for channe 2? I love haveing the eq for a boost, but I think that's the last thing left. Channel 2 sounds best as a heavy rythm, to me, but I need a nice sweet crunch crunch. HELP!!!!!!!!!!!!!!!!!
Boogiebabies
Well-known member
Maybe there is something wrong with channel 2. I have never had a problem getting a big crunch tone out of my MK IV. Using a 5751 is basically lowering the gain factor for the rest of the amp and not helping push the R2. I can attest that I do not get a nasally honk from the R2. I wonder if one of the LDR's are not switching a cap or resistor into the circuit.
The minute i try to put the gain up it gets all congested and compressed, channel 1 which I run all the way up on the gain sounds great. 1 stays open and dosen't compress. I know that part of more gain is the compressed sound, but there's no inbetween on 2. It's been only two gigs, three weeks, and 4 different speakers, el34's 6l6's, 6v6's, bias mod and all to get channel 2 to give me acdc crunch with cut. I can get crunch but you have to turn up the volume to get it to cut. Once you do that the volumes to loud. Channel 2 just dosen't sit right in the band context. If I didn't like the rest of the amp so much I would have given up by now. I thought of changing the value of the caps, but that would change the other channels too. I could change the value of the cap they have on the drive pot for two. Going back to dial in 2 again. thanks for the words, boogiebabie
Boogiebabies
Well-known member
I hate to hear that.
A little background on Mesa's is written in the patent application for the MK II. Mesa clearly states that their power amp is more of a class B than an A/B. Knowing that, I have always steered clear from bias mods and running hot tubes in any of my Mesa's. The whole preamp was designed to complement the power amp. After way too many bias pot and current draw experiments I can cleary state that when Mesa's get about 65% Max Plate Dissipation they turn to mush and are dead, bloated and lifeless. I dont run them over 60% period. At 60 you get quicker compression, but the headroom goes away. My case in point is my current MK IV power amp. I run GT 6L6GE's and GT 6CA7GE's, both in a #5. They all draw -25ma in the MK IV and sound absolutely incredible at 35% MPD. With the same amp and a really hot quad of JJ E34L's and JJ 6L6's, at 60% MPD the amp is pure mud. The cleans are really warm, but R2 and the Lead have too much natural bottom and and very little headroom. This is why I am not a bias pot enthusiast on Mesa's. Now, on an amp that is a real A/B I still never go over 60%. To my ears, it seems to be the sweet spot and allow for an even mix of compression and headroom. With Mesa's, all I find is mush. Call me crazy, but these amps were designed to be what they are for a purpose. Why are they so loud to begin with?
I find the MK series of amps to be two types of amp in one. First, a high preamp volume with a low power amp setting gives you a edgy and sharp tone. The second is a lower preamp volume and a much higher power amp setting. This brings out a very brown tone with harmonics, complexity and an overall rounded tone with sustain and controllable feedback. Depending on the tone I am looking for, I just adjust between the two. The most fun I have in the universe is when I run the IIC's with the Master at 5 and the Lead Master at 1.5. It's like heaven.
Just my thoughts.
A little background on Mesa's is written in the patent application for the MK II. Mesa clearly states that their power amp is more of a class B than an A/B. Knowing that, I have always steered clear from bias mods and running hot tubes in any of my Mesa's. The whole preamp was designed to complement the power amp. After way too many bias pot and current draw experiments I can cleary state that when Mesa's get about 65% Max Plate Dissipation they turn to mush and are dead, bloated and lifeless. I dont run them over 60% period. At 60 you get quicker compression, but the headroom goes away. My case in point is my current MK IV power amp. I run GT 6L6GE's and GT 6CA7GE's, both in a #5. They all draw -25ma in the MK IV and sound absolutely incredible at 35% MPD. With the same amp and a really hot quad of JJ E34L's and JJ 6L6's, at 60% MPD the amp is pure mud. The cleans are really warm, but R2 and the Lead have too much natural bottom and and very little headroom. This is why I am not a bias pot enthusiast on Mesa's. Now, on an amp that is a real A/B I still never go over 60%. To my ears, it seems to be the sweet spot and allow for an even mix of compression and headroom. With Mesa's, all I find is mush. Call me crazy, but these amps were designed to be what they are for a purpose. Why are they so loud to begin with?
I find the MK series of amps to be two types of amp in one. First, a high preamp volume with a low power amp setting gives you a edgy and sharp tone. The second is a lower preamp volume and a much higher power amp setting. This brings out a very brown tone with harmonics, complexity and an overall rounded tone with sustain and controllable feedback. Depending on the tone I am looking for, I just adjust between the two. The most fun I have in the universe is when I run the IIC's with the Master at 5 and the Lead Master at 1.5. It's like heaven.
Just my thoughts.
Boogiebabie, thanks for that. i am running in class A with GT-el34's biased at 30 ma. I'll try backing those down to 25 ma. I love to hear other guys chime in and tell me they have no problem getting a Marshall plexi tone 2, but it would really help more, if you were more specific, about it. Settings? what guitar and p/u's?, is your MKIV a combo? wide body? speaker stock? tubes? Do you own a Plexi? You don't have to give me this info, but if you want to type how easy it is, you might as well get into it. Sorry I mean this in the right way, I'm not trying to be a smart a@s. It's tough, when you put out big bucks on an amp and you just can't get the one channel to work for you. I put the stk C90 back in and it sounds just like the V30 that I had in there and the best speaker sound wise so far was the Celestion Neo Vintage. I'm stiking with the stk speaker for now. To much changing everything is a problem i have. Thanks again for the info.
ok, guitar Music Man Axis, and Fender American Deluxe Strat HSS with a Di-Marzio Tone Zone, MarkIV Sort Head, and 2x12 Recto Cab, 4 6L6's Mesa STR 440 Tubes, and No i don't have a Plexi but always jamin' with a Friend of mine which has one.
Boogiebabies
Well-known member
Like Antoine, who has great ears, it is Plexi like. There is no way it will be exact. The preamp topology is based on a Fender design with the tone stack coming right after the input signal. The Graphic EQ does a lot to help sculp the tone to be Plexi like. Do I own a Plexi, no. Have I, quite a few. They are brutally loud beasts that provide a big cruch at full volume.
Thanks to ole Jim, I don't hear as well as I used to, but it let me to the Mesa path and I could not be happier.
Using a 58 Les Paul with 9.1K Fralin Humbuckers through a Mesa 4X12 4FB
Standard slant with vintage 30's I have zero trouble get a big wide open crunch. Even through the EV in the combo, again, no problem. I use the gain on 10, Treble on 7 pulled, Bass 2, Mids 5, Presence 5 pulled.
Thanks to ole Jim, I don't hear as well as I used to, but it let me to the Mesa path and I could not be happier.
Using a 58 Les Paul with 9.1K Fralin Humbuckers through a Mesa 4X12 4FB
Standard slant with vintage 30's I have zero trouble get a big wide open crunch. Even through the EV in the combo, again, no problem. I use the gain on 10, Treble on 7 pulled, Bass 2, Mids 5, Presence 5 pulled.
Alright, now you guys are talking. Thanks for all the info, it all helps. Boogie man your settings are almost mine except for the drive setting, I'm only at 5, not pulled, I think my treble is a little higher, in the 7 to 8 range. I think I'm almost clean compared to you guys. i love the sound of the 2nd channel maxed and pulled, but that's way over the top for what my band plays. I'm an old guy (45yrs ) who does everything from Jay black to beatles, stones , who, Bon Jovi, Bruce, clapton. I think I'm there now, but that's what i thought last week. I think class A is going to help with the volume. I'm using a PRS single cut with stk #6 p/u's in it and a Gibson 59 RI with a custom 5 in the bridge and a seth lover in the neck. I may go back to the stk 57 classic in the bridge(8.9k vs 14k for the custom 5). How do you like the Fralin? I've only had his single coils (great stuff). again wasn't trying to piss anyone off, all the best.
Boogiebabies
Well-known member
45 !!! You Geezer... 
I like the Fralins, but I am still getting used to how clear they are compared to the 57 Classics. I switched because the Classics were so microphonic, but I loved the pickups to death. I found the Fralins new at a guitar show. A set of 9K / 8K for $ 200.00 with no tax and I was sold. I am using .022 tone caps and a home made volume kit. So far So good, but if I could pot the 57's I would put them back in.
I like the Fralins, but I am still getting used to how clear they are compared to the 57 Classics. I switched because the Classics were so microphonic, but I loved the pickups to death. I found the Fralins new at a guitar show. A set of 9K / 8K for $ 200.00 with no tax and I was sold. I am using .022 tone caps and a home made volume kit. So far So good, but if I could pot the 57's I would put them back in.
I had the same problem with one of the 57 p/u's. For some reason the neck 57 on my lp was bad. i tried taking the cover off and put electrical tape over the slugs and then putting the cover back on, still didn't work. The 57 in the bridge always sounded fantastic, but i got this mesa and I think I went a little nuts with my gear. I added a 500 pf cap and a 250 k resistor to the volume pots and i also went with 1 meg pots for the neck p/u only. one good thing about the custom 5, is I can split it. I added a pull pot on the tone pot and I can pull it out to split the bridge p/u. It makes for some cool sounds. I love LP's, this one has a nice neck, i had a 56ri which had a baseball bat for a neck.
My R2 is set like this : (it's a B version head, so if i remember well, BoogieBabies has said it's got a little more drive in the R2 channel)
Gain :5 (pulled) / Treble : 8 / Mids : 8 / Bass : 3 : Presence :6 (pulled)
The EQ is set as Follow :
80 : Top / 240 : Middle / 750 : Just on the first line / 2200 : Middle / 6600 Between the Middle and the Top line
Gain :5 (pulled) / Treble : 8 / Mids : 8 / Bass : 3 : Presence :6 (pulled)
The EQ is set as Follow :
80 : Top / 240 : Middle / 750 : Just on the first line / 2200 : Middle / 6600 Between the Middle and the Top line
thanks Antoine, do you have the eq on all the time for chn 2? The one thing I see is you guys are running the mids higher and your pulling out the presence. When I pull the presence out it really dulls the sound and lowers the volume a little. I've also noticed that the volume changes the tone. The main master on mine has to be at 2, other wise channel 2 sounds like crap. i can't belieave how loud this little combo is. thanks again, I'm getting there, I think, I hope LOL.
Boogiebabies
Well-known member
Hey Jamme,
If you get a chance, go to Antoine's my space link and listen to his solo on
Torna Una Volta. This guy is awesome.
http://www.myspace.com/antoinebeconcini
If you get a chance, go to Antoine's my space link and listen to his solo on
Torna Una Volta. This guy is awesome.
http://www.myspace.com/antoinebeconcini
I always use my EQ on my MarkIV, all the time on the 3 channels, never play without it !
BoogieBabies, thanks a lot bro for your support, you know i'm always a little embarassed by such comments about me but i really want to thank you for all these comments.
Sincerely BoogieBabies, it's an honor to be as well appreciated by someone like you, you are always here to help everyone, your knowledge about amps in general and particularly Mesa amps is impressive, it's a gift to have someone like you here, Thanks for all BoogieBabies.
BoogieBabies, thanks a lot bro for your support, you know i'm always a little embarassed by such comments about me
but i really want to thank you for all these comments.Sincerely BoogieBabies, it's an honor to be as well appreciated by someone like you, you are always here to help everyone, your knowledge about amps in general and particularly Mesa amps is impressive, it's a gift to have someone like you here, Thanks for all BoogieBabies.
Thank you Jamme61, it's a great amp beleive me, playing a MarkIV is an experience i will never forgot, once you've found your tones with this amp, it will be hard to play something else, just keep experimenting...
It's not my song, it's a studio session i've done last year for a Band of Corsica Island, the band is called "I Mantini", and it's not my band !
Yes i speak Italian, not as well as my wife, she's Italian, so if you want we can communicate in Italian Language !
Yes i speak Italian, not as well as my wife, she's Italian, so if you want we can communicate in Italian Language !
