new amp design request

[konstantine RK]

interesting thread here ppl

 

[rabies]

Using two separate amps just avoids all that. I do understand what you're asking for but it just isn't practical to get anywhere near as close as you would think without making things so complicated that it becomes counterproductive, and unless you do use different speakers it's all pretty irrelevant anyway, you may as well just find the best standard 2-channel amp you can and not worry about whether the sounds are 'exact' Fender and Marshall.

IIRC my RK1 had functionality that used cabA for channelX and cabB for channelY.

I never realized that the cab is more important for tone than the tubes. thx for the posts guys.

As always, "keep the dream alive".

It's obviously easy enough to by a JCM800 1x12 combo and a Fender twin reverb or similar. But I want one head! If the trannies really don't matter that much and can be shared b/n both power amps, then it may not weigh as much as I thought...

 

[rabies]

First of all I'd like to say I've enjoyed reading your posts for quite a while, even if I don't agree with all of them. :wink:

Don't agree? Well I don't agree with Condoleezza Rice's choice of pearl necklace, g string and goat vomit, but hey, that's just me... hanging with them redneck sons a bitchez!

 

[212Mavguy]

Rabies,

I definitely prefer pig vomit over goat vomit, especially when eating fat juicy steak.

8)

Good luck brudda, you a cool guy.

 

[94Tremoverb]

I thought some more about this, and actually the easiest way to get really close with one amp might be to get a Road King and modify it to bring each channel much closer to the Fender and Marshall circuits. I haven't seen a schematic or even inside one, but I would expect that it's at least theoretically possible to do that, even if it might mean quite a lot of changes - and the advantage would be that the hard work of building the switching power stage and speaker outputs has been done already. I would assume that the RK has a Fender-style early-tone-stack clean channel and Marshall-style cathode-follower/late-tone-stack distortion channels, since even the 3-channel Dual Rectifiers do - so it could be only really a job of changing component values, rather than rebuilding the whole layout. So that might give you a minimum-size rig of a head and a 2x12", if you had one side open-back with a Jensen-type speaker and the other closed with a Celestion-type.

If you had a RK and it still sounded too much like four channels of Mesa and not Fender and Marshall, the main reason is in the preamp design rather than the power stage. It's always puzzled me that since the MkIII Mesa have been claiming to get Fender, Marshall and Boogie sounds in the same amp, when actually the circuits are intentionally voiced quite differently and it just isn't possible to get those tones accurately. (Even discounting the tone stack placement in the Marks, which makes truly Marshall-like sounds impossible anyway.) I can understand why they would want to keep their own distinct sound identity, but why then claim to do the opposite... ?

 

[rabies]

Rabies,

I definitely prefer pig vomit over goat vomit, especially when eating fat juicy steak.

8)

Good luck brudda, you a cool guy.

who you be now?!

 

[rabies]

I thought some more about this, and actually the easiest way to get really close with one amp might be to get a Road King and modify it to bring each channel much closer to the Fender and Marshall circuits. I haven't seen a schematic or even inside one, but I would expect that it's at least theoretically possible to do that, even if it might mean quite a lot of changes - and the advantage would be that the hard work of building the switching power stage and speaker outputs has been done already. I would assume that the RK has a Fender-style early-tone-stack clean channel and Marshall-style cathode-follower/late-tone-stack distortion channels, since even the 3-channel Dual Rectifiers do - so it could be only really a job of changing component values, rather than rebuilding the whole layout. So that might give you a minimum-size rig of a head and a 2x12", if you had one side open-back with a Jensen-type speaker and the other closed with a Celestion-type.

If you had a RK and it still sounded too much like four channels of Mesa and not Fender and Marshall, the main reason is in the preamp design rather than the power stage. It's always puzzled me that since the MkIII Mesa have been claiming to get Fender, Marshall and Boogie sounds in the same amp, when actually the circuits are intentionally voiced quite differently and it just isn't possible to get those tones accurately. (Even discounting the tone stack placement in the Marks, which makes truly Marshall-like sounds impossible anyway.) I can understand why they would want to keep their own distinct sound identity, but why then claim to do the opposite... ?

I have a Rivera S120, only tube amp for a while now. 8 watts to 120 watts (main reason). anyways, Rivera claims to achieve the fender/marshall tone combo (2 channels) even in my 1992 amp. But with 4xEL34? not really.

Can somebody mod a RK2 (RK2 is supposed to have fantastic cleans) so that ch3/4 is TRULY a marshall sound? sounds like that's what we need. but the RK1 I had had a huge PCB.

The amps that everyone seems to REALLY like have simpler designs (less knobs) and smaller PCBs: JCM 800 2203 and IIC+. Correct?

If that's correct, then you could fit two of those PCBs in a single head maybe and re-purpose the RK2 power section, etc.

 

[94Tremoverb]

Is that Rivera one of the stereo ones? (I forgot the model numbers, sorry.)

If so, it may be possible to mod one side of the power section to run 6L6s, and switch power sections at the same time as preamp channels, maybe via the FX loop, although you might need to build some sort of custom switching box to achieve that. Each side would then go to its own speaker so you wouldn't need to worry about extra switching for them.

The size of the PCB isn't really an issue for tone, it's just because the RKs are very complex amps with a huge amount of switching and revoicing circuitry, whereas the early Marks and especially old single-channel amps like a 2203 are very simple.

I know what you mean about putting two PCBs in one box, years ago I wanted a Marshall with a JMP non-MV channel and a JMP MV channel in the same box (since Marshall have always avoided putting these two classic sounds in the same amp, for reasons known only to them), and I considered fitting two PCBs into the same chassis with stacked pots... it will fit, but even then it was a lot more work than I really wanted and in the end I found that a Tremoverb was quite close, but with tons of other cool stuff .

 

[rabies]

Is that Rivera one of the stereo ones? (I forgot the model numbers, sorry.)

If so, it may be possible to mod one side of the power section to run 6L6s, and switch power sections at the same time as preamp channels, maybe via the FX loop, although you might need to build some sort of custom switching box to achieve that. Each side would then go to its own speaker so you wouldn't need to worry about extra switching for them.

The size of the PCB isn't really an issue for tone, it's just because the RKs are very complex amps with a huge amount of switching and revoicing circuitry, whereas the early Marks and especially old single-channel amps like a 2203 are very simple.

I know what you mean about putting two PCBs in one box, years ago I wanted a Marshall with a JMP non-MV channel and a JMP MV channel in the same box (since Marshall have always avoided putting these two classic sounds in the same amp, for reasons known only to them), and I considered fitting two PCBs into the same chassis with stacked pots... it will fit, but even then it was a lot more work than I really wanted and in the end I found that a Tremoverb was quite close, but with tons of other cool stuff .

S = stereo, so yes. The bias sweep range handles tubes other than EL34 family. Not sure about 6L6 though, but perhaps. Never tried it. But I can't currently footswtich b/n channels and use only one power amp if both are hooked up to speaker cabs (it's both or one, no switching).

 

[rabies]

The Riveras don't seem to have that marshall crunch.

 

[94Tremoverb]

I was thinking that if you put an A/B box in the FX loop you could select which power section you were using, with each one driving its own speaker. To tie that in with the channel switching you would have to build a box with a dual switch that did both at the same time, but that's pretty simple.

The lack of Marshall crunch could maybe be fixed by modding the circuit, but I'm not familiar enough with these amps to suggest how...

 

[theroan]

Wow, you guys need to branch out in your amp knowledge.

http://www.egnateramps.com/Products/Renegade/RenegadeHead.html

Has a tube blend feature on both channels.

Additionally, for the cost of a nicer Mesa couldn't you just have a Fender Twin and JCM 800?

Budda Dual Stage 30 also does it.

 

[rabies]

Wow, you guys need to branch out in your amp knowledge.

http://www.egnateramps.com/Products/Renegade/RenegadeHead.html

Has a tube blend feature on both channels.

Additionally, for the cost of a nicer Mesa couldn't you just have a Fender Twin and JCM 800?

Budda Dual Stage 30 also does it.

blendable is different from channel switching (i.e. 100% EL34 or 100% 6L6 via footswitch)

 

[94Tremoverb]

While I haven't played that amp, or even seen one, I would also take a bet that it's just another 2-channel amp that doesn't sound quite like a Fender or quite like a Marshall - it may be great, but that isn't the same thing. (As I would say the Tremoverb or the Rivera are great amps that don't sound exactly like a Fender or a Marshall.)

There is also one further problem with the straightforward two-amp idea, not yet mentioned - I can't speak for rabies, but I use a lot of effects, some of them in the amp's loop. This becomes very difficult with two amps - the routing and switching necessary to run the same effects in two different loops would add at least as much complexity again as switching heads and cabs, and the only other option is to duplicate all the effects you would want to run with both amps - and is impossible with the classic Fenders and Marshalls anyway without modding them, since they don't have loops. Nor do the Marshalls have reverb, so you would have to add that. This all adds up to an impractical amount of gear for smaller venues, not to mention costing *more* than a new Mesa-type amp.

The great thing about a channel switcher with reverb and an FX loop is that all those problems are taken care of in one neat package. The difficult bit is to make it sound like two separate amps .

 

[talltxguy]

I like the post.

How about a MIDI controlled power amp that lets you run EL34s, 6L6s, or a combination of both; AND allows you choose between tube rectifier or diodes. Don't put deep or half drive on it so that you can still market the 2:90, which is a great amp. I'd like it to be simul-class, but wouldn't get too upset if it wasn't.

Would also like to see a KT88 powered beast similar to the ol' Mesa 50/50 in that it's simple and straightforward and loud! Perhaps 4 KT88s on each channel?

 

[theroan]

Wow, you guys need to branch out in your amp knowledge.

http://www.egnateramps.com/Products/Renegade/RenegadeHead.html

Has a tube blend feature on both channels.

Additionally, for the cost of a nicer Mesa couldn't you just have a Fender Twin and JCM 800?

Budda Dual Stage 30 also does it.

blendable is different from channel switching (i.e. 100% EL34 or 100% 6L6 via footswitch)

???

The Renegade has two channels each with a seperate tube mix. The 2nd is british voiced. You can get 100% of either tube by diming the tube mix to either side. Sounds exaclty like what OP wants.

 

[vitor gracie]

The Renegade has two channels each with a seperate tube mix. The 2nd is british voiced. You can get 100% of either tube by diming the tube mix to either side. Sounds exaclty like what OP wants.

It's not. I have spent hours playing one in a closed room over the course of a few days. Tried different cabs, compared it to higher end amps (Bogner, Boogie, Hi Watt, etc) Its just not. I almost bought it. The tube blend knob is a gimmick. It's really cool on paper but turning the amp up and actually playing it loudly, there is an indistinguishable difference in the settings of the knobs. The differences are so subtle, that as soon as you place a drummer in the room those differences are invisible. It sounds like itself. The gain is Marshally in that the distortion is more crispy and tight. The clean is just clean. I didn't think to myself, "WOW! This is JUST LIKE my old '65 Twin I used to have!" Not even close. It's just a nice clean.

While I haven't played that amp, or even seen one, I would also take a bet that it's just another 2-channel amp that doesn't sound quite like a Fender or quite like a Marshall - it may be great, but that isn't the same thing.

Right on the money. The force is STRONG with you sir.

People seem to think that the magic of a Marshal is in the EL34s or of a Fender is in the 6L6s. But there is so much more to it then that as '94Tremoverb pointed out. I once considered having 2 separate single spaced racks made, each voiced like the amps in question, (Fender clean, Marshall dirty) and was going to run them through a RJ16 http://www.rjmmusic.com/rg16.php and through a nice stereo power amp (one per side, fender side going through a open back 2X12, Marshal side going through a 4X12) and would try to get the most pure tone like that. I got my prices for all of it and realized that if I could just live with an amp that had a great clean and dirty, it would be cheaper, less gear to bring, less complicated, and really make me just focus on playing. (I am back to using just a 2X12 Trem O Verb)

That was my solution. I think we tend to chase stuff cuz of the thrill of the hunt. However, when we get what we want, we always want more. LOL. Thats my 2 cents. If you can have an amp like that built, (what the OP was talking about wanting) I'll be the first to try it!

 

[212Mavguy]

This is without a doubt one of the best threads that has happened here in at least months....

Still standing by my first post...

Still.

Vitor, god bless ya for the last sentences starting with "I got my prices..."

Priceless, sir. Well done.

Trem, ya outdone yourself here, major kudos.

Rabies, you're imaginative, think outside the box, and basically awesome.

Plan b...

The optical silent Mesa switching thang would have to work in the hugely more voltage and current filled power sections as well as the pre's, and yes, best is for two different pre's, power sections, and OT's. OT has more effect on tone than many think, at least that's my take on doing it and smelling the solder fumes from significantly dissimilar OT's within the same circuit... All could be run from the same power supply, though.

But...

By the time you do that you got one heavy mutha. So back to my first post for practicality. External a/b/y switching for perfectly great Fender and Marshall amps man portable and brought together on and for the same stage.

Peace.

 

[YellowJacket]

OK, here is my nuisance post for the day!

Fender clean + Marshall dirt = Mesa Boogie ElectraDyne.

This amp definitely lends credence to the role of circuit design in tone. As has been said over and over again, tubes are just the icing on the cake when it comes to tone. The amp simply has to be designed in such a way that gives it the sound we want. Of course, this gets right back into this argument about how the Dyne should use 2 6L6s for clean and 2 EL-34s for dirt and the circle goes round and round again. Answer me this though, does the Dyne not sound dang British on Vintage Hi even WITH 6L6s plugged in? Yes? I thought so . . .

 

[vitor gracie]

...By the time you do that you got one heavy mutha. So back to my first post for practicality. External a/b/y switching for perfectly great Fender and Marshall amps man portable and brought together on and for the same stage.

Peace.

Hit the nail on the head man. If you want a '65 Twin sound and a JCM 800, then by all means, just go out and get the two amps and us an a/b switch. If you can swing it, do it.

Fender clean + Marshall dirt = Mesa Boogie ElectraDyne.

With all due respect, I disagree. An ElectraDyne sounds like an ElectraDyne. The clean is nothing like any Fender I have ever plugged into. The mids are completely different in character and the only similarity to the cleans on an ED and, say, a Twin is that they are both kinda jangley and bright. Also, the dirty was not supposed to do the Marshal thing at all...not even a little bit. (I owned a Silver Jubilee Head and a JCM 800 for about a year) That's what the Stiletto series was for. The ED (to me) is Mesa's attempt to offer guys the Orange tone hands down. When Mesa said "British tones" I believe they where talking about the "other" british company. :lol: Orange is the Mesa killer right now, with tons of new, young artists using their products. It's very trendy and that company has carved out their own market and pushed themselves on the newer scene for sure. I love it.

Mesa is simply "preventing" loyal followers like us from crossing over with the ElectraDyne. That is not meant to be a negative statement. Just an observation. Put an ED in a room full of Rockerverbs, and AD50s and you'll see what I mean. I did. It's very apparent A-Bing them what Mesa was trying to do. I, however, feel that if I need an Orange tone, I'll use an Orange. That's not to say I don't approve of the ED, just that my tastes and guitars like the real Mc Coy. I mix em, TOV head and an Orange cab. Though I don't think I would ever own an Orange head. Just studio usage...

212Mavguy, I think your solution is the wisest.

...and your name is making me want my Mavericks back. I should have never sold them.