Amp modeler for tweak-heads

Maybe this is old news to some, but I never heard of this before and thought this was pretty cool...

I was demoing some amp modelers this weekend and came across a decent one by Peavey (Revalver Mark III). While it's still not a real amp, it seems that it might be cut above the others I tried, and will serve my purpose as a temporary sound until I can re-amp later. It uses convolution reverbs and convolution cabinets too. However, the coolest part of the software is this: It's tweakable down to the component level.
















If it does a reasonable approximation of these parameters, it should be an excellent learning tool for the eternal noob like me. At the very least, it's got to be a hell of a lot more fun than spice modeling.

I'm going to spring the $250 for this software.

-Chris

> It's tweakable down to the component level.



So all my years of learning vacuum-tube audio chakra have been reduced to Lego-style poke-and-play?

For a mere $250?

From a company which reJECTed vacuum tubes from the start, didn't get into them until Raytheon had sucked its last bottle?

http://www.peavey.com/products/revalver/

What are the limits on the Demo version? 30 days? 3 models? no saving?

LOL. I thought the same about the Peavey/Valve connection. After poking around a little more, it looks like Peavey simply bought a one-man company to get this product:

Revalver Mark II

The Mark II version is also a little cheaper after discounts. Surprisingly, there were no Peavey amps in the Mark II version. :wink: I've played around with the software for a couple hours so far, and one of my favorite things so far is that they surpringly have a model of my favorite bass amp, my 70's Fender Bassman 100. They captured the vibe of that amp pretty well. As far as other amps go, the usual modeling issue applies; the more gain, the less real it sounds. Still, it's a great place holder, and I'd probably use it as a keeper wherever I would use a solid state amp (leads, bass, misc.). I haven't got into the deep tweaking too much, but frankly I wouldn't know if the component level modeling does a reasonable approximation.

The demo is the full version, no expiration, no saves and a burst of white noise every minute or two.

[quote author="PRR"]>


From a company which reJECTed vacuum tubes from the start, didn't get into them until Raytheon had sucked its last bottle?

[/quote]

Huh ?

While I only worked there 15 years, I know a little about the history (aided by a book written by Ken Achard when he retired a few years ago).

The first guitar amp Hartley ever "designed", in the basement of his parents house, back in the '60s before he started the company, was a tube amp. Solid state was the uncommon technology back then. He like most others relied on the tube manual heavily.

Early on Hartley recruited Jack Sondermeyer away from RCA for his solid state expertise.

While Peavey sold far more solid state amps than tube, they had a tube amp in the line as far back as late '60s-early '70s ( VTA-400). I recall several tube amps during my time there, but I was not a guitar guy so it wasn't an area of personal interest. The 5150 may be the only iconic Peavey tube amp, and that sound was mostly tweaked to satisfy Eddie's tastes.

Hartley has always had an "everyman" value orientation when targeting products and markets. I thought the transtube, solid state tube mimics sounded good to me (but I repeat I don't play).

Peavey designed more tube gear than the market was willing to buy, I'm not sure if that is a shortcoming of the design, or a "good for the money" brand perception that was too difficult to overcome. Kind of like the "cute" blind date...nobody wants. I suspect Hartley was always a tube guy and his customer's overwhelming preference for low cost solid state is what you're reacting to.

If Peavey only offered tube amps he'd probably have gone out of business long ago. The customers IMO made that decision for him.

JR

I've used the original ReValver... Not bad.

I'm skeptical about this new stuff. I'm still waiting (or want to help with) a SPICE modeler that makes DivX plugs for mixing use.

I've looked into the whole SPICE-like sim for real-time DSP, and I think there's a very valid reason nobody has put one out yet. As it is, DSP has been slowly moving to having its own "first principles" instead of being based on electronic circuits. This has been leading me toward the idea of building a virtual guitar "amp sim" that has very little in common with anything in the analog world.

Here's an interesting paper by a fellow at NI that has some cool ideas in it:

http://www.native-instruments.com/fileadmin/redaktion_upload/pdf/KeepTopology.pdf

In particular, the bilinear integrator is a pretty cool idea. In theory at least, once you solve a few issues, a combination of integrators, multipliers, and routing can create any IIR filter imaginable. It also makes it easy to embed non-linear waveshapers as part of the filter's impulse response, as the entire filter is not running as a single differential equation (which would then need the non-linearity "embedded" in it, which can be tricky). I am, however, still struggling to understand some of this, and could be talking out of my rear end.

This might be the closest we'll get to being able to draw circuits in software that can immediately be heard and used via DSP.

Regarding Zavalishin: looks interesting. I like how the author acknowledges that the stuff may be out there but he's not familiar with all of the literature. And who could be these days?

There are still a few things I don't understand in his paper. The accompanying paper, which shows how to implement these ideas in Reaktor, helps explain things more:

http://www.native-instruments.com/fileadmin/redaktion_upload/pdf/KeepTopologyRC.pdf

At least now there are pictures showing how everything interacts.

Something else also just occurred to me. Dr. Julius Orion Smith III, inventor of physical modeling and owner of quite possibly the coolest name in the Universe, describes a form of synthesis called "lumped models" here:

http://ccrma.stanford.edu/~jos/pasp/Introduction_Lumped_Models.html

It centers around individual models of masses, springs, and dashpots, which correspond in electronics terms to inductors, capacitors, and resistors, respectively. In his book (which I linked to), he talks about ways of digitizing systems of these components such that DSP networks of these components can be built directly. This could be the answer to your "SPICE-like DSP system" if you can understand any of it (I can glean a decent portion of the text). I don't know if there are any patent issues or not.

[quote author="Consul"] ...Dr. Julius Orion Smith III, inventor of physical modeling [my italics] and owner of quite possibly the coolest name in the Universe...[/quote]

A slight overstatement I'd say, although it is a cool name :grin:

From the wiki "Physical modeling synthesis":

"Although physical modelling was not a new concept in acoustics and synthesis, having been implemented using finite difference approximations of the wave equation by Hiller and Ruiz in 1971, it was not until the development of the Karplus-Strong algorithm, the subsequent refinement and generalization of the algorithm into the extremely efficient digital waveguide synthesis by Julius O. Smith III and others, and the increase in DSP power in the late 1980s that commercial implementations became feasible."

Well, his was the system that Yamaha licensed for use in their physical modeling synths. I should have been more specific and said the inventor of the bi-directional waveguide, which was key to a lot of what came after. (The bi-directional waveguide is a computationally efficient way of solving the acoustic wave equation in real time.) Either way, the point is, he knows his stuff. :wink:

Nevertheless, the lumped models appendix of his book might prove useful in this discussion.

> The first guitar amp Hartley ever "designed", in the basement of his parents house, back in the '60s before he started the company, was a tube amp.

He built a personal amp in 1957-1958. Out on the porch I have Shea's 1955 book on transistor audio amps... transistors were NOT ready for stage-amps.

He "started Peavey Electronics" in 1965, in his Dad's basement. If he produced a few tube amps, these have been overwhelmed by his massive and bleeding-edge investment in solid-state amps as soon as (even a few months before) they were practical. Hartley had the Vision, and he was right. 90++% of stage musicians want transistor amps. They are a third the weight of a tube amp, and even the worst ones sound fine once the keg is tapped.

I remember those days, Delco car radios, the RCA books, Dan Meyer's several Tigers, the 1st generation Dyna amps. The Delcos actually worked well, if hot and ripe. Building a 10-15W push-pull home-use hi-fi was not too hard; there is a 1964 SuperScope at work still functional. But it has been lucky. I know I could kill it in 67 milliseconds.

The RCA published plans worked fine on test-load but lacked protection. I killed an "indestructable" Tiger, which got me a job repairing the Dynacos' " novel circuits... which automatically and instantly protect the amplifier". Second-breakdown was not well understood. My knack for deciphering odd tranny circuits like the Flickenger comes from piles of dead undocumented transistor amps needing quick repair. Hartley brought us solid-state amps which could be as real-world on-tour reliable as tube amps. (And Crown; but most of us could not afford to look at a Crown DC-300!)

Hartley also gave us GOOD hi-output fair-price speaker drivers, the Black Widows.

And some very practical fault-free stage mixers.

I dunno why he gets no respect. Or why any un-kissy comment gets his fans' shorts in a bunch.

> a tube amp ... late '60s-early '70s VTA-400

I sit corrected.... though at that power level, tubes were the "best choice" through the 1960s, unless you had to have extended earthquake response (the "DC" in "DC-300").

> solid state tube mimics sounded good to me

I'm sure that 90+% of people with a preference would score 50:50 on a good blind test, and it would be trivial to trick them into a lower score with a lushified sand amp and a glassy tube amp. In fact I sold my surviving Tiger with a self-built JFET preamp to a guitarist, and he was amazed it had no tubes. (It was a cheat: I used Fender Twin EQ with Yamaha Electric Grand JFET plagiarisms. Steal from the best.)

> If Peavey only offered tube amps he'd probably have gone out of business

Of course. CBS-Fender's trash left room only for Marshall and some bottom-feeders (some of them very fine, but pinched for profit). Peavey made the transistor stage amp practical, sold it well. Even so it is frikkin amazing that the name is still around, much less still under the founder's leadership. That's not electronic technology, that's serious business acumen.

I for one would love to hear any comments from you PRR on how individual tweaks in the software affects sound vs your instincts on what would happen ITRW with similar physical tweaks.

ITRW(In The Real World)


extremely interesting to me, I have a new Marshall and I am in love with its texture, the modeling amp I had doesnt come close to the textures.

[quote author="amorris"]I have a new Marshall and I am in love with its texture, the modeling amp I had doesnt come close to the textures.[/quote]
One is covered in genuine tolex, the other is a poly-vinyl imitation...

:wink:

On a serious note, wasn't Hartley also retained by Eddie Van Halen to 'tweak' his amplifiers? -A former colleague of mine was a tour manager for VH in the early '80s and I recall him mentioning that Hartley was 'flown in' from time to time to 'do things' and keep everything to EVH's satisfaction.

-Those were the golden days of VH, and Eddie could afford anything he wanted. -The amps were Marshall-badged, but had been "Hartleyed" inside, was the story I heard...

Keith

Here's my take on Peavey amps. I came of musical age in high school the early 80's, so it seemed like every other amp in my universe was a Peavey, and they were all solid state. If they had tube amps on the market, we didn't know about them (and couldn't afford them anyway). The first Peavey tube amp I ran into was in 1995 when I was recording a friend's band. He always had some kind of Boss overdrive going so he could switch from clean to dirty live, and I never really cared for his sound. When we got in the studio, I asked him to turn off the overdrive and turn up the amp's gain for his crunch sounds. The results were stunning, it was a really good amp.

In '84, my guitarist was playing through a Peavey solid state bass head and an Ampeg 15" cabinet. I was playing bass through a 50 watt Kalamazoo 2x10 with EL34's. We probably should have traded :wink: .

-Chris

there are many things that can scar one for life

i remember being crushed when i showed the " peavey papers "
a newsletter brochere thing to an older electronics repairing bass playing
friend and said " look it has a Fuzz control AND a distortion knob ! "
and he said No , no you want a Marshall or a small fender .

Some of the best advice i've ever gotten , now if i hadn't been married ,
stopped playing live and sold several Marshall over the years , i'd be
more Happy !

One of the sentiments i agree with about modeling amps , is that they
often sound better when someone else is playing them [ or in track ]
cause they just don't have the same feel , but then again nothing sounds
like a LOUD amp cept for a loud amp where the gtr becomes very live
and all the nuances come through

[quote author="SSLtech"][quote author="amorris"]I have a new Marshall and I am in love with its texture, the modeling amp I had doesnt come close to the textures.[/quote]
One is covered in genuine tolex, the other is a poly-vinyl imitation...

:wink:

On a serious note, wasn't Hartley also retained by Eddie Van Halen to 'tweak' his amplifiers? -A former colleague of mine was a tour manager for VH in the early '80s and I recall him mentioning that Hartley was 'flown in' from time to time to 'do things' and keep everything to EVH's satisfaction.

-Those were the golden days of VH, and Eddie could afford anything he wanted. -The amps were Marshall-badged, but had been "Hartleyed" inside, was the story I heard...

Keith[/quote]

I can't imagine Hartley tweaking on a Marshall amp, while Eddie probably had his pick of several amp hot rodders chatting him up in So. Cal. Rumor is he would variac his amps down to lower mains voltage in the studio to get more/different distortion. Lots of empty boxes on tour.

When Eddie worked with Peavey on the joint development of an EVH amp I'm sure Hartley was involved in the broad strokes discussions, but the development and tweaking on the 5150 was done by the amp designer (J. B.) who made several visits out to Eddie's studio. I recall Eddie and Val visiting MS at least once. Eddie probably more times as PV also developed a signature guitar with him (Wolfgang). Eddie was involved in seemingly minor details like type of wood used in 5150 amp baffle and side panels.

JR

[quote author="PRR"]> The first guitar amp Hartley ever "designed", in the basement of his parents house, back in the '60s before he started the company, was a tube amp.

He built a personal amp in 1957-1958. Out on the porch I have Shea's 1955 book on transistor audio amps... transistors were NOT ready for stage-amps.

He "started Peavey Electronics" in 1965, in his Dad's basement. If he produced a few tube amps, these have been overwhelmed by his massive and bleeding-edge investment in solid-state amps as soon as (even a few months before) they were practical. Hartley had the Vision, and he was right. 90++% of stage musicians want transistor amps. They are a third the weight of a tube amp, and even the worst ones sound fine once the keg is tapped.

I remember those days, Delco car radios, the RCA books, Dan Meyer's several Tigers, the 1st generation Dyna amps. The Delcos actually worked well, if hot and ripe. Building a 10-15W push-pull home-use hi-fi was not too hard; there is a 1964 SuperScope at work still functional. But it has been lucky. I know I could kill it in 67 milliseconds.

The RCA published plans worked fine on test-load but lacked protection. I killed an "indestructable" Tiger, which got me a job repairing the Dynacos' " novel circuits... which automatically and instantly protect the amplifier". Second-breakdown was not well understood. My knack for deciphering odd tranny circuits like the Flickenger comes from piles of dead undocumented transistor amps needing quick repair. Hartley brought us solid-state amps which could be as real-world on-tour reliable as tube amps. (And Crown; but most of us could not afford to look at a Crown DC-300!)

Hartley also gave us GOOD hi-output fair-price speaker drivers, the Black Widows.

And some very practical fault-free stage mixers.

I dunno why he gets no respect. Or why any un-kissy comment gets his fans' shorts in a bunch.

> a tube amp ... late '60s-early '70s VTA-400

I sit corrected.... though at that power level, tubes were the "best choice" through the 1960s, unless you had to have extended earthquake response (the "DC" in "DC-300").

> solid state tube mimics sounded good to me

I'm sure that 90+% of people with a preference would score 50:50 on a good blind test, and it would be trivial to trick them into a lower score with a lushified sand amp and a glassy tube amp. In fact I sold my surviving Tiger with a self-built JFET preamp to a guitarist, and he was amazed it had no tubes. (It was a cheat: I used Fender Twin EQ with Yamaha Electric Grand JFET plagiarisms. Steal from the best.)

> If Peavey only offered tube amps he'd probably have gone out of business

Of course. CBS-Fender's trash left room only for Marshall and some bottom-feeders (some of them very fine, but pinched for profit). Peavey made the transistor stage amp practical, sold it well. Even so it is frikkin amazing that the name is still around, much less still under the founder's leadership. That's not electronic technology, that's serious business acumen.[/quote]

Sorry If I sound overly defensive... you wouldn't believe the crap I heard during 15 years in those trenches.

Re: Hartleys first amp, I guess I could pick up the phone and ask him but I don't care enough to waste what little good will I may have left on that question. I was escorted out of the building by guards when I quit several years ago. :roll:

Hartley attended his first NAMM show in '55 as a high school student. His dad owned a music store. He was in the HS band playing trumpet or something like that but wanted to be like Bo, after seeing him play in '57.

According to the bio, his first amp was based on a RIAA preamp circuit out of a tube manual, built over christmas vacation. It's a "friendly" bio so a tube amp does sound cooler. FWIW he made his own electric guitar with a pickup he hand wound on the dining room table. He was all over the popular hobby magazines so I'm sure he was exposed to solid state projects, early on. I would be surprised if he didn't mess with transistors too, but the book has a picture of his circa '60 tube amp.

re: the RCA design manuals, Hartley experienced the same poor reliability in the early days. It was when he called RCA for answers he ended up talking to Jack Sondermeyer, who understood the shortcomings in those manuals since he probably wrote some of them. Hartley recruited Sondermeyer away from RCA and I credit Jack with Peavey's BSH (brick_house) reputation. Jack was no slouch with tube stuff too. He was involved with VMP- tube mic pre, and VCL- tube comp designs, that IMO compare favorably with high end studio gear.

I have many criticisms of Peavey, I quit over differences I had, but I will reflexively challenge criticisms I consider undeserved. Peavey getting into virtual amps doesn't strike me as such a stretch. Peavey was early to embrace massively DSP based sound systems (Media Matrix) replacing racks full of black boxes in large installs with virtual gear.

JR

A timely coincidence: I got acquainted with the hardware design staff at Line 6 yesterday. A nice bunch of folks from what I could gather in a short meeting. I was given a tour of the facility and found it quite impressive. They seem to be thriving, despite these increasingly tough times.

The lobby has a lot of their products on display. As I'm sure most of you know, they specialize in digital-domain emulation of vintage equipment.

One of the fascinating bits was their museum of reference equipment used in developing and validating the DSP stuff. I'm not sure how well-received my comment was about the eBay opportunities behind the glass doors :grin:

[quote author="JohnRoberts"]Lots of empty boxes on tour.[/quote]
Oh yes. -WALLS of amplification/cabs. Many were empty boxes, One was plugged in and mic'ed, another was a working spare, ready-to-go, but most were empty.

That was my reaction too: "HP... -working on a MARSHALL???" -but I was told (and I only have this from two sources, albeit two moderately reliable ones) that Hartley was "flown in a few times" to work on "Eddie's amps". -Whether this was merely super-early-stage discussions on future product lines, I don't know, but I certainly took it to mean tweaking/modding, and yes, I too have heard that variacs were used.

other than that, I have no way to corroborate nor disprove the tales... -but I too was dubious of the idea of HP working on JM's "Model-T" style product.

Keith

While I worked there Hartley had one or more planes. A nice King Air turbo prop for short hops and a I think a G-II (later a G-IV) that made visits to Corby or Frankfurt less painful (if we ignore that one time we returned back into the country via Miami :roll: from parts south). So I find it a little odd that somebody would brag they flew Hartley somewhere.

I could imagine some symbolic laying on of hands by Hartley, if he was romancing Eddie to participate in a larger commercial venture. Hartley was surely capable of tweaking on a Marshall (or whatever), if suitably motivated. IMO it would take more than a plane ticket and a back stage pass.

I guess it depends on who is telling the story, to whom.

JR