Roots Of The Recto?

[screamingdaisy]

Someone should modify that wiki entry then.

The problem is that Mike Soldano keeps telling people he took ideas from the Mark II and used them in the SLO, but 3124 disagrees with him.

Anyway, this was all covered earlier and Afu has asked us to not go off topic so I'm dropping the subject.

 

[user 21540]

Someone should modify that wiki entry then.

The problem is that Mike Soldano keeps telling people he took ideas from the Mark II and used them in the SLO, but 3124 disagrees with him.

Hahaha -- this is awesome.

 

[3124+]

Someone should modify that wiki entry then.

The problem is that Mike Soldano keeps telling people he took ideas from the Mark II and used them in the SLO, but 3124 disagrees with him.

Anyway, this was all covered earlier and Afu has asked us to not go off topic so I'm dropping the subject.

What ideas did he take from the Mesa Mark II?

 

[afu]

Someone should modify that wiki entry then.

The problem is that Mike Soldano keeps telling people he took ideas from the Mark II and used them in the SLO, but 3124 disagrees with him.

Anyway, this was all covered earlier and Afu has asked us to not go off topic so I'm dropping the subject.

What ideas did he take from the Mesa Mark II?

All the Marshall-ish designs before the SLO had two main amp stages and two direct coupled stages to drive the tone stack. All of these stages used 100k anode resistors. Stage 2 used a high cathode resistor to pull the signal into less-than-linear operation, but stage 3 and 4 have very little gain and are more about feeding the cathode follower enough amperage to remain stable and drive the tone stack without a large loss in volume.

The Marshalls, unless pushed with a pedal, would break into heavy power amp distortion before heavy preamp distortion.

The Mark II has a different topology and uses some stages to provide make-up gain, but used cascading preamp stages to reach overdrive before the power section. The stages also use anode resistors that are above 100k, which compresses the signal much more than a Marshall. Notably, the first stage has a 220k resistor.

The Mark II creates a lot of preamp distortion by cascading multiple stages, which are compressed to reach saturation and cutoff more quickly. While the power amp section will distort when driven hard enough, the master volume is there to provide preamp distortion to the power amp so it can reproduce it at various volumes. Oh, and it has channel switching for the first time ever.

If Soldano was inspired by the Mark to apply its lessons to the SLO, I imagine the inspirations could be:

Larger anode resistors.
A master volume just before the phase inverter, instead of after it.
An extra stage to use cascading gain effectively w/the MV.
A very large cathode resistor on stage 3 pulls the bias into a completely non-linear area of operation near cutoff, mimicking extra gain stages, but with only one VERY large gain. It's squishier than using multiple stages.
Channel switching.

If that is correct, Mesa didn't "steal" the SLO if it was kind of the way Mesa would do that topology. It makes some of the changes from SLO to DR make more sense. If Marshall started with the Bassman circuit, Soldano married the Mark with a Marshall, and Mesa took it back to the Bassman (and Vox), it would appear as if the DR was meant more like "Old is New again". The Blue Angel and Heartbreaker are even more of a nod. Fascinating.

 

[3124+]

The Mesa Mark II does not use 220K plate resistors on V1. In fact, some Mark II revisions have relatively small 82K plate resistors instead! There is no high value cathode resistor cold clipper circuit in a Mark II. The topology is totally different. Check the schematics. Also have a look at the '70s Marshall 2203 schematic and you will see the use of a master volume control directly off the treble pot wiper, same exact topology used in the SLO. You will also see the 10K cathode cold clipper. And the 2203 circuit has loads of preamp distortion at any volume level without pedals.

Also check out the earliest revision of the '70s Marshall 2204 and you will see their use of a 330K plate resistor on the second gain stage. Going further back to the early 60s, the Vox AC30 was using 220K plate resistors on V1.

 

[afu]

You're right. I was looking at the IIc+. It's 150k there. The cold clipping stage on it is stage 2 of the lead circuit. I can't read the cathode resistor well, because it looks like someone wrote this in Sharpie, but it looks like a 22k.

I know there's a 10k cathode resistor on a 2203. That's hardly as cold as 22k or 39k. As a matter of fact, I allude to it in my post. While 10k pulls it toward being cold, the later designs that use larger cathode resistance pull it down into being completely non-linear at idle. That's a big difference. Throwing in an extra stage before it for some cascading gain is even more different.

In any case, before making the SLO as it's known, Mike was modifying Mark IIs and calling them his. I don't think you're getting the overall point that ideas from all kinds of sources inspired amp makers to improve on the 70s designs to get more distortion at lower volumes. For instance, Mesa designed their pre-PI MV and Marshall borrowed it from them.

At this point, you're being stubborn to make someone prove to you that Mike didn't glean any inspiration from the Marks after modifying them and I don't think any answer is going to satisfy you. The cascading gain, MV, and channel switching would have been influential to a person growing up with minimal stage, non-MV, non-switching amps which relied on power amp distortion for the overdrive.

 

[3124+]

I'm looking at the Mesa Mark IIc+ schematic. The second stage of the lead circuit (V4A) is not a cold clipper. The cathode resistor in that circuit is 3.1K. The higher value (22K?) resistor you are referring to is there to lower gain by attenuating current flow through the cathode bypass cap.

Marshall didn't borrow Mesa's master volume design. If anything, Marshall's master volume circuit was influenced by the '73 Sunn Model T or Hiwatt stuff.

The Mesa Mark designs are based on Fender blackface topology. Soldano designs are derived from Marshall and tweed Bassman topology. I have seen plenty of Soldano modded Marshall heads around, but never a Soldano modded Mesa Mark II. Where are they now?

 

[siggy14]

I'm looking at the Mesa Mark IIc+ schematic. The second stage of the lead circuit (V4A) is not a cold clipper. The cathode resistor in that circuit is 3.1K. The higher value (22K?) resistor you are referring to is there to lower gain by attenuating current flow through the cathode bypass cap.

Marshall didn't borrow Mesa's master volume design. If anything, Marshall's master volume circuit was influenced by the '73 Sunn Model T or Hiwatt stuff.

The Mesa Mark designs are based on Fender blackface topology. Soldano designs are derived from Marshall and tweed Bassman topology. I have seen plenty of Soldano modded Marshall heads around, but never a Soldano modded Mesa Mark II. Where are they now?

Wow you just have to prove yourself right and just cant shut up, Mike Soldano has been quoted as designing the SLO based off his modding of Mark Series amps. If I had just read it once I would think someone is making it up, but over the many years I have read quotes of people talking to him saying he has said that so I rate it at about 75% accurate. As to how the SLO came about, Doesn't matter the circuits are not alike, it is obvious while doing the Mark's something clicked in him from the design and modding them and influences him on creating the SLO, just like Randall started by modding Fenders that gave him the ideas for the Marks.

With that being said Randall has gone way further then Mike ever did on designing amps by his many patents and innovations, so many different flavors from the mark series to the recto series to lonestars and stilettos and all others throughout the years and the features on most of these amps are many.

Mike's amps also sound great but there are not nearly as innovated and complex as Randall's Designs and a good bunch of them revolve around the SLO preamp with watered down features and a different power section, and the amps that are not designed around the SLO preamp are not that popular.

People like Randall and Bogner get it, most guitarists want multiple channels with multiple voicing and solo boost with a long list of features. They are also not afraid to take their pride and joy flagship amps and keep making changes to them to make them better and updated. They are not afraid to make different amps that stray away from the flagship amp with a different voice and just keep giving more choices.

So Yes the SLO is a kick *** if I wanted just that one tone and had the ability to blast it all the time then I would go with a SLO, but for me I would rather have a Boogie with the many different voicing and options.

 

[cyber104]

"Wow you just have to prove yourself right and just cant shut up"

Yeah - I agree - he needs to just shut up now and stop the pissing contest

 

[afu]

After all that:

Soldano took general concepts and developed them into his own style, which is awesome. Mesa took Soldano's preamp style and tweaked it until it worked for their concept. The switching and voicing were innovations on top of Soldano's innovation. The way the Mesa power amp switching operates is unique. All the different changes and original designs make the sound shift away from a SLO. The sound is further separated and refined as new models are developed.

This brings me around to the original question: what was the concept? Another question: how did the concept change as time went on? Were the further revisions and models created for meeting customer demand or was there a clear vision?

 

[Shemham]

This brings me around to the original question: what was the concept? Another question: how did the concept change as time went on? Were the further revisions and models created for meeting customer demand or was there a clear vision?

I think the concept was originally in the same ballpark with the SLO and Rectifier was supposed to compete in the same sphere with the other "Marshall-like" amplifiers used in the hair metal scene. I think it's really plausible if you look at the features.

Bold/Spongy feature is obviously inspired by EVH using variac with his Plexi Marshall and must be one of the earliest features planned for the Rectifier. As it did not play such a crucial role with the Rectifier as with Eddie's cranked non-MV Marshall, it could have been implemented mainly to draw attention from wannabe-Eddies when the concept was still an amplifier for the 80's metal heads. With the tube rectifier, you could conceptually 'brown out' the amp even further (well, if you don't care about the deafening volume levels) which could pretty much fit the same bill. I find it somewhat funny that Mesa implemented such power amp heavy features into an amp where most of the tone comes from the preamp section. But in the end, it works.

Aside from the tonestack, power sections features and the fx loop, the original Dual Rectifier had very few differences between the circuits compared to SLO. The power supply filtering was dropped to proper levels with the tube Rectifiers. Some of the minor differences were implemented to control parasitic oscillation e.g. 20pf capacitor on the grid of V2a and snubbing caps on the phase inverter power rails (presumably to help with the Modern mode). In Rev D I think they dropped the presence level a bit to make the sweep more practical for most of the people. Also, I remember user AdmiralB mentioning that the Rev C effect loop did not functions as intended due to a capacitor installed the wrong way around. After that, Mesa started to build the clean which lead to using the LDRs on preamp cathodes and rewiring the first filter network.

In a way, I think Mesa ended up with the true Dual Rectifier tone by accident by trying to amend some of the weaknesses in their original design. I don't believe Mesa had any exact visions of the final Rev G tone when they had Rev C in front of them, but I'm quite sure the decreased brightness was due to customer demand. I tried 220kohm presence pot à la rev C for kicks. And yeah, it was very bright. I can see most of the people staying under 10 o'clock setting with that.

 

[screamingdaisy]

In a way, I think Mesa ended up with the true Dual Rectifier tone by accident by trying to amend some of the weaknesses in their original design. I don't believe Mesa had any exact visions of the final Rev G tone when they had Rev C in front of them, but I'm quite sure the decreased brightness was due to customer demand. I tried 220kohm presence pot à la rev C for kicks. And yeah, it was very bright. I can see most of the people staying under 10 o'clock setting with that.

It would be interesting to know what kind of artist feedback Mesa got from the first round of Rectifiers being sent out and how it influenced the design. There wasn't exactly a lot of time between the Rev C and Rev F.

I'd also be interested to know if the Rev G's change in tone was intentional, a consequence of trying to fix something else, or if it was some sort of happy accident.

 

[3124+]

As to how the SLO came about, Doesn't matter the circuits are not alike, it is obvious while doing the Mark's something clicked in him from the design and modding them and influences him on creating the SLO, just like Randall started by modding Fenders that gave him the ideas for the Marks.

Okay here's the real story straight from the man himself. In 1980, after working two years at an auto body shop, Mike Soldano saved all of $1455 and bought a Mesa Mark II. Turns out he was really disappointed in the Mesa and its numerous shortcomings.

This is what motivated Mike Soldano to design the ultimate amp. Explains why the SLO has absolutely nothing in common with Randall's Mark II circuit.

 

[afu]

(Lots of great stuff)

Thanks for the info. I agree about the Spongy/Tube options having an influence from Van Halen. I remember that time pretty well, as I was a teenager. When I think of the distorted, guitar oriented, bands that would be a target demographic, a continuum comes to mind:

Retro (Black Crowes)
Pop Metal (Poison, Van Hagar)
Hard Rock (Skid Row, GnR)
Metal 1 (Ozzy, Priest)
METAL 2 (Big 4, Death)

Due to the trends and the emergence of Thrash and Death Metal, I recall Pop, Hard and Metal 1 kind of being lumped together as "Hair" (marketing wise) in 1989 - 1991 and sharing a lot of the same sounds. I remember the brown sound being huge. I also remember people like John Christ and that @sshat from Poison playing with treble and presence set to 'kill'. The Back-To-Basics trend was already coming around, but wasn't the norm, yet and the Metal 2 guys used more bass than the others.

I've had zero time with a Rev C, but listening to it mixed with Bogner and modified Marshalls on AIC's Dirt and doing some math to compare the response in comparison to Rev G and a 3 Channel, it would have been very bright by comparison. Just the presence and gain controls make a huge difference. In less than 2 years time, they went from C to G, right?

I remember that the most prominent bands using the Rectos in the mid-90s were Candlebox, Soundgarden, Bush, and Metallica. Soundgarden would have been using Rev G-based Tremoverbs. Kirk Hamster had a Rev G Racto. Someone correct me if I'm wrong, but James had a modified and heavily processed Triaxis Recto (marked 'Recto' as opposed to his C+ 'Crunchberries'). I have no idea what the other two used. When I think of rhythm, I think of Hetfield. When I think of modifications and bottom end, I think of Hetfield. Metallica was bigger than Jesus. I dunno, but Load had some great tones on it. All of those bands used "darker" sounds, but Bush was probably late to the party and grabbed it to sound like the Nirvana-tail coats they were.

The original clean was sensitive to guitar volume settings and not very clean for a clean/crunch use, but, perhaps, for old school guys. The final clean had more headroom, but still a lot of harmonic content, but was more of a quiet-to-loud, clean/crunch, ala Grunge and Alt Rock, and eventually those Korny guys. The Solid State clean that Metallica uses just isn't possible, but I really like my clean channel.

 

[screamingdaisy]

Rev C through F happened over a period of months. Im not sure exactly when the change happened but I can say that the were making Fs before the end of '92. I don't know if G was late 93 or early 94... Maybe someone else can fill in that detail.

I thought Bush was a Big Muff.

Hetfield had a Triple Recto and I suspect that would've been used for recording prior to the TriAxis being modded. I've also seen him with Tremoverbs.

The clean on my Rev F is usable, but bland. It's been years since I used the clean channel but I remember it being dry, somewhat stiff and mid humped. For cleans I prefer to switch to the red channel (modern) and roll my guitars volume down.

 

[afu]

Bush is listed on the Mesa site as users. Nigel with a DR; Gavin with a TR.

Hetfield had the twin Triaxis rig from the touring for Load until before touring St. Banger (except one tour with Wizards). One Triaxis used the Recto setting. The Triples were used for Lollapalooza and other shows that weren't Metallica productions. The other amps were for warm-up.

While looking for schematics to look at changes from each revision, I saw some info with a person claiming their Rev F was dated 12/93, which would be about the end of that series. Rev G was coming out pretty much at that time. Maybe it was a case of cleaning out the closet to not waste money on unused boards?

 

[Jorn218]

I apologise in advance, but wondered about this upon reading this thread. In regards to the choice of rectification, does the tube rectification work better in adding in tube sag saturation when using Raw and/or Pushed vs. Vintage or Modern? I have yet to try it myself, but seeing how Raw and Pushed seem to reduce the preamp gain(distortion), could these modes be enhanced when using the Spongy Tube Rectification which at volume would grind up better allowing the poweramp saturation in? Seems like it may to me after reading what you guys wrote, and from my experience with the Vintage and Modern modes where Tube rectification and Spongy seems to take away, or be a detriment to the sonic palette from those amp modes to "MY" ears.

 

[screamingdaisy]

I apologise in advance, but wondered about this upon reading this thread. In regards to the choice of rectification, does the tube rectification work better in adding in tube sag saturation when using Raw and/or Pushed vs. Vintage or Modern? I have yet to try it myself, but seeing how Raw and Pushed seem to reduce the preamp gain(distortion), could these modes be enhanced when using the Spongy Tube Rectification which at volume would grind up better allowing the poweramp saturation in? Seems like it may to me after reading what you guys wrote, and from my experience with the Vintage and Modern modes where Tube rectification and Spongy seems to take away, or be a detriment to the sonic palette from those amp modes to "MY" ears.

Typically, I like the tube rectifier on cleans and lead and diode on crunchy/chuggy rhythm.

On cleans and lead the tube rectifier softens the attack and adds a natural compression.

On heavy rhythm the tube rectifier struggles too much. Big power cords near the nut draw a lot of power and when the amp is sagging hard I don't get as much punch. Using diode keeps the amp as percussive as possible.

 

[Jorn218]

I apologise in advance, but wondered about this upon reading this thread. In regards to the choice of rectification, does the tube rectification work better in adding in tube sag saturation when using Raw and/or Pushed vs. Vintage or Modern? I have yet to try it myself, but seeing how Raw and Pushed seem to reduce the preamp gain(distortion), could these modes be enhanced when using the Spongy Tube Rectification which at volume would grind up better allowing the poweramp saturation in? Seems like it may to me after reading what you guys wrote, and from my experience with the Vintage and Modern modes where Tube rectification and Spongy seems to take away, or be a detriment to the sonic palette from those amp modes to "MY" ears.

Typically, I like the tube rectifier on cleans and lead and diode on crunchy/chuggy rhythm.

On cleans and lead the tube rectifier softens the attack and adds a natural compression.

On heavy rhythm the tube rectifier struggles too much. Big power cords near the nut draw a lot of power and when the amp is sagging hard I don't get as much punch. Using diode keeps the amp as percussive as possible.

I agree with you on all those points. This is why I posited my question/ interpretation on what was being said. The tube rectifier along with the spongy mode, acts somewhat as a built in variac as mentioned earlier. Seeing how this amp was designed originally and targeted towards the Hair Metal scene and those guitarists really sought the VH1 sound and were trying to emulate that by using the Van Halen lie of using a variac to get his Brown Sound (actually had more to do with unmatched tubes than anything early on). The inclusion of these two items would probably work best using them with the Raw and Pushed channel modes to get the most out of that feature.

Using the tube rectifier on heavy rhythms tends to give whats being played almost a reverse gate feel and the amp loses its percussive nature. Clicking the Spongy feature emphasizes this.

 

[afu]

Tube vs Diode on Pushed or Raw is Led Zeppelin I vs Back In Black. Soft/Crisp.

Spongy/Tube gets really dark on mine and it mushes up. That works for things on Raw and Ch. 1. I turn the bass waaaaaaaaaaay down to compensate for what sounds like a light film on the trebly bits. Vintage can work, as long as the gain is kept in the "bright" area before 11:00, but pushing Raw is more fun for me.