Framus Cobra a copy of a Recto?

[Ola Englund]

That Recto clip brought the pain

It had that nearly out of control sort of beast on a chain vibe. Perfect for the track played. The fizz, chainsaw buzz, all part of that evil rip you face off voicing.

Again, thx Ola for the great clips.

you're welcome

 

[Sixtonoize]

you dont understand, however, that Mike Soldano invented the SLO design first - a one off that no one else had done. not marshall, fender, or anyone.

a SLO does not resemble a marshall and i do not care what you say, there is nothing identical in design at all. not even the same tube stages and output tube design.

Touchy, are we?

I'm not saying that the SLO wasn't a revolutionary design that defined what a "modern" amp was - my point was that every amp design that exists builds on the groundwork of the designs that came before it. And it's not like the SLO is exactly 100% original - the power section looks suspiciously like the back end of the Mesa Mark I, which came along some 20-ish years prior...and wasn't exactly an original design then, either.

The revolutionary thing about the SLO is the cold clipping stage, which, as far as I know, no other amp builder had used before, and few modern amps omit. That's totally unique. However, the rest of the schematic is old tech - cascaded gain stages, a buffered FX loop, and a very familiar power section. Sure, Mike Soldano managed to combine the old ideas in a new and unique way, but that doesn't mean that he created an entirely new design from scratch...he took ideas that worked and modified them into something unique.

 

[glpg80]

you dont understand, however, that Mike Soldano invented the SLO design first - a one off that no one else had done. not marshall, fender, or anyone.

a SLO does not resemble a marshall and i do not care what you say, there is nothing identical in design at all. not even the same tube stages and output tube design.

Touchy, are we?

I'm not saying that the SLO wasn't a revolutionary design that defined what a "modern" amp was - my point was that every amp design that exists builds on the groundwork of the designs that came before it. And it's not like the SLO is exactly 100% original - the power section looks suspiciously like the back end of the Mesa Mark I, which came along some 20-ish years prior...and wasn't exactly an original design then, either.

The revolutionary thing about the SLO is the cold clipping stage, which, as far as I know, no other amp builder had used before, and few modern amps omit. That's totally unique. However, the rest of the schematic is old tech - cascaded gain stages, a buffered FX loop, and a very familiar power section. Sure, Mike Soldano managed to combine the old ideas in a new and unique way, but that doesn't mean that he created an entirely new design from scratch...he took ideas that worked and modified them into something unique.

A: i know more about the design of the SLO than most people would know.

B: there is no tube dedicated to buffering an effects loop in a standard SLO. just a grid break and careful cathode bias resistor that follows it for dB drop consideration.

C: The power section was not identical to any other manufacturer at the time of its invention. i know people who build SLO clone's just for the amplifiers power section of immense headroom and huge volume capabilities.

D: Mike got lucky with the 39k. thats all im saying. the same is true with krank's model revolution. there is a design flaw trying to apply a bias method and they goofed by accident. the accident actually worked in their favor, the rest is history.

E: when you design something as an engineer you design from ideas not patent copies. one is called innovation the other is called evolution. get a dictionary.

and i do take offense dude. especially when i am designing an amplifier to be released from the ground up - no jose mods, no hairy mods, no SLO copies, nothing. and its a slap in the face to call my work a copy of someone else's design. the mathmatics and application of an amplifier might be the same, but that is as far as the similarities go.

 

[Heritage Softail]

you dont understand, however, that Mike Soldano invented the SLO design first - a one off that no one else had done. not marshall, fender, or anyone.

a SLO does not resemble a marshall and i do not care what you say, there is nothing identical in design at all. not even the same tube stages and output tube design.

Touchy, are we?

I'm not saying that the SLO wasn't a revolutionary design that defined what a "modern" amp was - my point was that every amp design that exists builds on the groundwork of the designs that came before it. And it's not like the SLO is exactly 100% original - the power section looks suspiciously like the back end of the Mesa Mark I, which came along some 20-ish years prior...and wasn't exactly an original design then, either.

The revolutionary thing about the SLO is the cold clipping stage, which, as far as I know, no other amp builder had used before, and few modern amps omit. That's totally unique. However, the rest of the schematic is old tech - cascaded gain stages, a buffered FX loop, and a very familiar power section. Sure, Mike Soldano managed to combine the old ideas in a new and unique way, but that doesn't mean that he created an entirely new design from scratch...he took ideas that worked and modified them into something unique.

A: i know more about the design of the SLO than most people would know.

B: there is no buffered effects loop in a standard SLO. just a grid break.

C: The power section was not identical to any other manufacturer at the time of its invention. i know people who build SLO clone's just for the amplifiers power section of immense headroom and huge volume capabilities.

D: Mike got lucky with the 39k. thats all im saying. the same is true with krank's model revolution. there is a design flaw trying to apply a bias method and they goofed by accident. the accident actually worked in their favor, the rest is history.

E: when you design something as an engineer you design from ideas not patent copies. one is called innovation the other is called evolution. get a dictionary.

and i do take offense dude. especially when i am designing an amplifier to be released from the ground up - no jose mods, no hairy mods, no SLO copies, nothing. and its a slap in the face to call my work a copy of someone else's design. the mathmatics and application of an amplifier might be the same, but that is as far as the similarities go.

Commercial or personal amp design project? Just curous. I don't have a dog in this fight... Although I do have an SLO. I am slimming down the list of my first amp kit build. That is daunting enough. Designing one is in some galaxy far far away.....

 

[glpg80]

it will be commercial if the proto model gets any love. the company is a company i have been running for home networks for a while called ACI which is an acronym.

talking with companies right now about laser etched front panels and material costs/ideas.

there will also be powder coating available upon request.

if you look in the RT section i created a topic asking about clean channels and everyone's needs? that was not by accident.....

 

[Sixtonoize]

A: i know more about the design of the SLO than most people would know.

I'm not disputing that. I was just trying to make a point about how every amp builds on the designs that came before it and you got really offended about a throwaway comment made for illustrative purposes only.

B: there is no tube dedicated to buffering an effects loop in a standard SLO. just a grid break and careful cathode bias resistor that follows it for dB drop consideration.

Doesn't the last stage before the output jack act as a CF?
What makes it different than a regular CF setup?

C: The power section was not identical to any other manufacturer at the time of its invention. i know people who build SLO clone's just for the amplifiers power section of immense headroom and huge volume capabilities.

What's different about it? From the schematics I've seen, it looks just like the power section that Mesa had been using in the Mark series with additional filtering.

D: Mike got lucky with the 39k. thats all im saying. the same is true with krank's model revolution. there is a design flaw trying to apply a bias method and they goofed by accident. the accident actually worked in their favor, the rest is history.

Interesting that the most famous aspect of the SLO was due to bad design, not brilliant engineering.

E: when you design something as an engineer you design from ideas not patent copies. one is called innovation the other is called evolution. get a dictionary.

I didn't use either of those words in my previous posts.
I don't know why you think I need a refresher on what they mean.

and i do take offense dude. especially when i am designing an amplifier to be released from the ground up - no jose mods, no hairy mods, no SLO copies, nothing. and its a slap in the face to call my work a copy of someone else's design. the mathmatics and application of an amplifier might be the same, but that is as far as the similarities go.

Last I checked, I didn't insult your work.
Unless you're secretly Mike Soldano incognito. In which case, I apologize.
You make great amplifiers and I am humbled by your presence.

 

[Mailman1971]

 

[glassjaw7]

Woah, this thread took an unexpected turn now didn't it? Not choosing sides, but I don't think anyone was trying to insult anyone else here. Just a misunderstanding or words taken the wrong way.

Matt, finish your proto man! I want to hear that damn thing!

 

[Sixtonoize]

Matt, finish your proto man! I want to hear that damn thing!

Definitely a statement I can get behind.
If there's something new happening in the amp world, I'm all ears

 

[glpg80]

Matt, finish your proto man! I want to hear that damn thing!

Definitely a statement I can get behind.
If there's something new happening in the amp world, I'm all ears

re-read my edited post on the CF comment.

the rest of your BS im going to pretend you did not write. there is a difference in bad engineering, and grabbing the wrong value resistor

yes, there is something new happening in the amp world. to start a company takes money to invest. it does no good for me to talk about it. ill let my prototype do all of the talking when it stands beside some of the more respected amplifiers in the industry.

my goal is to build an amplifier that can stand beside either a CCV or a Dino939 and hold its own - without jose modifications, SLO copies, and fender bassman schematics as you seem to be pointing out.

that is all im saying. my sources and such do not concern you as it seems by the smartass comment at the end? suite yourself if you would like. im only telling the truth. whether or not you want to believe it is up to you

 

[thiswaythatway]

Funny but i think the Cobra is what a Recto sounds like after the Saturday morning kids gets done tweaking it at Guitar Center.

 

[jasonP]

The Cobra is a ripoff of a Dual Rec is a ripoff of an SLO is a ripoff of a JCM800 is a modification of a JTM45 is a ripoff of a Tweed Bassman is a ripoff of the RCA Tube Designer's Handbook.

There's not a single amp out there that isn't a ripoff of something else.
Unless it's 100% identical, it's not a ripoff; it's just progress.

that RCA book is over 30 chapters long and filled with awsome information. it is one hell of a read though. the bible of tube radios - the third edition is the edition i have and was wrote in 1959

you dont understand, however, that Mike Soldano invented the SLO design first - a one off that no one else had done. not marshall, fender, or anyone.

same as fortin and DAR - complete one off designs from their own engineering backgrounds.

back to the SLO - the amplifiers that Jerry listed are rip-offs of the SLO design.

a SLO does not resemble a marshall and i do not care what you say, there is nothing identical in design at all. not even the same tube stages and output tube design.

AFA the companies that copied the SLO - they are all identical to a T except for build quality, HT/B+, and their tonestacks.

thats it.

I don't know if I'd say there identical. I mean just look at the Rectifier on top of what you said. In red mode the feedback loop is lifted and off the tone stack the the presence is a cut control? Then the filtering is different to the pre-amp tubes as well as there differences in the PI. In the orange they look to partially bypass the cathode caps? Looks to have more feedback...
I do agree though that there is similarity between the two. If you have seen the schematics to the stiletto it also uses the 39k cold clipper. That amp does some cool things with relays, imo

 

[diagrammatiks]

you dont understand, however, that Mike Soldano invented the SLO design first - a one off that no one else had done. not marshall, fender, or anyone.

a SLO does not resemble a marshall and i do not care what you say, there is nothing identical in design at all. not even the same tube stages and output tube design.

Touchy, are we?

I'm not saying that the SLO wasn't a revolutionary design that defined what a "modern" amp was - my point was that every amp design that exists builds on the groundwork of the designs that came before it. And it's not like the SLO is exactly 100% original - the power section looks suspiciously like the back end of the Mesa Mark I, which came along some 20-ish years prior...and wasn't exactly an original design then, either.

The revolutionary thing about the SLO is the cold clipping stage, which, as far as I know, no other amp builder had used before, and few modern amps omit. That's totally unique. However, the rest of the schematic is old tech - cascaded gain stages, a buffered FX loop, and a very familiar power section. Sure, Mike Soldano managed to combine the old ideas in a new and unique way, but that doesn't mean that he created an entirely new design from scratch...he took ideas that worked and modified them into something unique.

A: i know more about the design of the SLO than most people would know.

B: there is no tube dedicated to buffering an effects loop in a standard SLO. just a grid break and careful cathode bias resistor that follows it for dB drop consideration.

C: The power section was not identical to any other manufacturer at the time of its invention. i know people who build SLO clone's just for the amplifiers power section of immense headroom and huge volume capabilities.

D: Mike got lucky with the 39k. thats all im saying. the same is true with krank's model revolution. there is a design flaw trying to apply a bias method and they goofed by accident. the accident actually worked in their favor, the rest is history.

E: when you design something as an engineer you design from ideas not patent copies. one is called innovation the other is called evolution. get a dictionary.

and i do take offense dude. especially when i am designing an amplifier to be released from the ground up - no jose mods, no hairy mods, no SLO copies, nothing. and its a slap in the face to call my work a copy of someone else's design. the mathmatics and application of an amplifier might be the same, but that is as far as the similarities go.

Man I love the SLO. To give credit where credit's due, Mike was probably one of the first people to design a properly function preamp distortion amp. Bad ass preamp into an ultra linear power amp section.

Umm that being said...some of your points just aren't true.

Example..B. Not true. There is definitely a tube stage dedicated to the FX loop. When you bypass the loop it bypasses that buffer stage.

C. It's an ultralinear hifi power amp. Mike's innovation there was adapting it for guitar amp use when everyone else was saying to build distortion into the circuit.

--- The schematics for the JCM800 and the SLO are almost identical until the loop. The SLO has both inputs folded into the V1a/V1b - the hi/lo becomes regulated by the clean crunch switch. In the avenger the lo bypasses a stage completely, in the slo the clean switch cuts like 90 percent of the signal being fed into the v1.

From all the interviews I've read, Mike was a miffed that EVH took his design and Mesa stole other parts of it...but at the end of the day...the Recto doesn't work or sound anything like the SLO...

Mike would never build an amp like the Recto anymore then Mesa would ever build an amp like the slo. You start adding in channel switching, tube rectifiers, changing tubes around, adding reverb, adding tone stacks, presence, depth, etc etc...it's not the same amp.

 

[glpg80]

The Cobra is a ripoff of a Dual Rec is a ripoff of an SLO is a ripoff of a JCM800 is a modification of a JTM45 is a ripoff of a Tweed Bassman is a ripoff of the RCA Tube Designer's Handbook.

There's not a single amp out there that isn't a ripoff of something else.
Unless it's 100% identical, it's not a ripoff; it's just progress.

that RCA book is over 30 chapters long and filled with awsome information. it is one hell of a read though. the bible of tube radios - the third edition is the edition i have and was wrote in 1959

you dont understand, however, that Mike Soldano invented the SLO design first - a one off that no one else had done. not marshall, fender, or anyone.

same as fortin and DAR - complete one off designs from their own engineering backgrounds.

back to the SLO - the amplifiers that Jerry listed are rip-offs of the SLO design.

a SLO does not resemble a marshall and i do not care what you say, there is nothing identical in design at all. not even the same tube stages and output tube design.

AFA the companies that copied the SLO - they are all identical to a T except for build quality, HT/B+, and their tonestacks.

thats it.

I don't know if I'd say there identical. I mean just look at the Rectifier on top of what you said. In red mode the feedback loop is lifted and off the tone stack the the presence is a cut control? Then the filtering is different to the pre-amp tubes as well as there differences in the PI. In the orange they look to partially bypass the cathode caps? Looks to have more feedback...
I do agree though that there is similarity between the two. If you have seen the schematics to the stiletto it also uses the 39k cold clipper. That amp does some cool things with relays, imo

i do agree there are too many 2nd hand variables to list to name why they are different as an amplifier in a whole.

but it goes back to innovation versus evolution - taking someone else's idea and running with it.

to run in the other direction is alot more complicated.

 

[glpg80]

Example..B. Not true. There is definitely a tube stage dedicated to the FX loop. When you bypass the loop it bypasses that buffer stage.

i am going to give you a quick lesson in tube buffering, series loops, series parallel loops, and what mu deals with in gain - the technical correct term

the SLO uses a triode of V3 and a triode of V4 with V4 biased with gain, not clean reproduction, of the series connection between the other half of V3.

the cathode follower is used before the serial effects loop as an impedance buffer as to not load anything down you connect to the jacks - which is NOT dedicated to its own design but is quite literally a part of the amplifiers tone due to the .1 isolation capacitor that connects it/limits its use in the first place and the auto-compression characteristics of the lead tone when more volume is added.

that never happens with dedicated tube effects loop designs unless the tube is purposely put into the signal, and also deals with the designer even using a cathode follower for buffering in the first place. the effects loop i have designed does not use a cathode follower at all.

its a serial loop design that is a part of the SLO tone and is not the same as a dedicated effects loop used after a tonestack where most tonestacks are placed (and for the same reason)

understand the differences and applications of effects loops. one design is not like the other.

C. It's an ultralinear hifi power amp. Mike's innovation there was adapting it for guitar amp use when everyone else was saying to build distortion into the circuit.

--- in the slo the clean switch cuts like 90 percent of the signal being fed into the v1

wrong again. in a SLO - you always have 100% signal fed to the clean and overdrive channels. the clean channel is 180* out of phase to the lead channel. the design purpose was to minimize parts to maximize tone. there is absolutely no cutting of signal anywhere. what you are hearing are varactors/opto-isolators grounding out the lead channel for the clean channel.

You start adding in channel switching, tube rectifiers, changing tubes around, adding reverb, adding tone stacks, presence, depth, etc etc...it's not the same amp.

you shape tone with those, not create it. you are in a different world when circuit designing is being mentioned. the dB increases of an AC wave from a guitar string are made with transistors. core tones after these amplifcation stages/during them depending on the model amplifier we are talking about can change with the designs and features you have listed.

that is why i said there is a difference in innovation, and evolution. two key differences here. do not get them confused with "tone" which is what is happening here.

 

[jasonP]

Example..B. Not true. There is definitely a tube stage dedicated to the FX loop. When you bypass the loop it bypasses that buffer stage.

i am going to give you a quick lesson in tube buffering, series loops, series parallel loops, and what mu deals with in gain - the technical correct term

the SLO uses a triode of V3 and a triode of V4 with V4 biased with gain, not clean reproduction, of the series connection between the other half of V3.

the cathode follower is used before the serial effects loop as an impedance buffer as to not load anything down you connect to the jacks - which is NOT dedicated to its own design but is quite literally a part of the amplifiers tone due to the .1 isolation capacitor that connects it/limits its use in the first place.

a serial/parallel effects loop has its own dedicated tube dealing with unity gain coming into the tube in one stage - balanced inputs after the stage, and output that is not a stage biased for more dB gain amplification.

its a serial loop design that is a part of the SLO tone and is not the same as a dedicated effects loop used after a tonestack like its supposed to be used. understand the differences and applications of effects loops. one design is not like the other.

C. It's an ultralinear hifi power amp. Mike's innovation there was adapting it for guitar amp use when everyone else was saying to build distortion into the circuit.

--- in the slo the clean switch cuts like 90 percent of the signal being fed into the v1

wrong again. in a SLO - you always have 100% signal fed to the clean and overdrive channels. the clean channel is 180* out of phase to the lead channel. the design purpose was to minimize parts to maximize tone. there is absolutely no cutting of signal anywhere. what you are hearing are varactors/opto-isolators grounding out the lead channel for the clean channel.

You start adding in channel switching, tube rectifiers, changing tubes around, adding reverb, adding tone stacks, presence, depth, etc etc...it's not the same amp.

you shape tone with those, not create it. you are in a different world when circuit designing is being mentioned. the dB increases of an AC wave from a guitar string are made with transistors. core tones after these amplifcation stages/during them depending on the model amplifier we are talking about can change with the designs and features you have listed.

that is why i said there is a difference in innovation, and evolution. two key differences here. do not get them confused with "tone" which is what is happening here.

Other then the OT being "hi-fi" is the power amp really designed in a hi-fi matter? I mean the PI is a copy of an old Marshall right? If we want to talk about a "hi-fi" designed power amp I would think we would look at what VHT is doing with his amps. Maybe I'm wrong here.

 

[JerryP]

SLO ultra linear power amp?

Marshall Major was using an ultra linear power amp in the 60's. So were Sunn amps. Dawk modded Majors in 60's & 70's that had a high gain preamp into an ultra linear power section.
Jerry

 

[glpg80]

i didnt/dont think so. but one thing the SLO poweramp side has going for it (not the filter stages) is core mil-spec resistors and no BS added anywhere to the circuits.

the definition of hi-fidelity is reproduction of the original sound in the most accurate way possible.

to be honest, if it were hi/fi - it would not be class A/B push pull

 

[diagrammatiks]

Example..B. Not true. There is definitely a tube stage dedicated to the FX loop. When you bypass the loop it bypasses that buffer stage.

i am going to give you a quick lesson in tube buffering, series loops, series parallel loops, and what mu deals with in gain - the technical correct term

the SLO uses a triode of V3 and a triode of V4 with V4 biased with gain, not clean reproduction, of the series connection between the other half of V3.

the cathode follower is used before the serial effects loop as an impedance buffer as to not load anything down you connect to the jacks - which is NOT dedicated to its own design but is quite literally a part of the amplifiers tone due to the .1 isolation capacitor that connects it/limits its use in the first place and the auto-compression characteristics of the lead tone when more volume is added.

that never happens with dedicated tube effects loop designs unless the tube is purposely put into the signal, and also deals with the designer even using a cathode follower for buffering in the first place. the effects loop i have designed does not use a cathode follower at all.

its a serial loop design that is a part of the SLO tone and is not the same as a dedicated effects loop used after a tonestack where most tonestacks are placed (and for the same reason)

understand the differences and applications of effects loops. one design is not like the other.

C. It's an ultralinear hifi power amp. Mike's innovation there was adapting it for guitar amp use when everyone else was saying to build distortion into the circuit.

--- in the slo the clean switch cuts like 90 percent of the signal being fed into the v1

wrong again. in a SLO - you always have 100% signal fed to the clean and overdrive channels. the clean channel is 180* out of phase to the lead channel. the design purpose was to minimize parts to maximize tone. there is absolutely no cutting of signal anywhere. what you are hearing are varactors/opto-isolators grounding out the lead channel for the clean channel.

You start adding in channel switching, tube rectifiers, changing tubes around, adding reverb, adding tone stacks, presence, depth, etc etc...it's not the same amp.

you shape tone with those, not create it. you are in a different world when circuit designing is being mentioned. the dB increases of an AC wave from a guitar string are made with transistors. core tones after these amplifcation stages/during them depending on the model amplifier we are talking about can change with the designs and features you have listed.

that is why i said there is a difference in innovation, and evolution. two key differences here. do not get them confused with "tone" which is what is happening here.

What? The question was whether a tube is buffering the signal of the effects on the send and return. Are you saying there is nothing being done to the signal as it leaves the jack and then returns? I'm not disagreeing that the SLO's fx loop is unique to the SLO, the Avenger has a different layout..but other then a really genius way to implement a loop, that stage isn't responsible for the SLO's sound.

SLO ultra linear power amp?

Marshall Major was using an ultra linear power amp in the 60's. So were Sunn amps. Dawk modded Majors in 60's & 70's that had a high gain preamp into an ultra linear power section.
Jerry

but the majors liked to explode : (. Regardless there's a design spec change by the time Mike and the other guys hit the field. The majors were still about being cranked.

i didnt/dont think so. but one thing the SLO poweramp side has going for it (not the filter stages) is core mil-spec resistors and no BS added anywhere to the circuits.

the definition of hi-fidelity is reproduction of the original sound in the most accurate way possible.

to be honest, if it were hi/fi - it would not be class A/B push pull

I mean just because there's a preference for single ended hifi reproduction now....
doesn't mean you can't do it any way you want.

http://www.mcintoshlabs.com/products/1300.asp

 

[glpg80]

listen bro ive got the two degrees in electrical and computer engineering, whether you want to believe me or not on the SLO is totally up to you. ive only studied that amplifier for 5 years, wrote papers on it, disected it, learned from it.

what do i know?