Amp Emulations

[tcobretti]

Thankss a lot guys
Its true the only fet stompbox Ive built is the Blue Magic, So Ill have to try a ROG one
Which one is the most touch sensitive for you guys?
For the tube amp Im saving some money becuase right now Im bankrupt
Cheers
Rafa

Eighteen = really crunchy Marshall over drive
Thunderchief = Plexi styled distortion
Uno = hot Fender distortion
English Channel = Vox OD that is almost a distortion
Prof Tweed = Fender OD

I'd say any but the T-Chief is gonna be fairly touch sensitive, so pick what sounds good to you.

[Rafa]

What about the ROG matchless (matchbox) is it as touch sensitive as the other ones.
Cheers
Rafa

[Gus]

some good posts in this thread

I am not again the JFET circuits they can be cool and IMO are their own sound.

IIRC there was a dumble schematic or two on the web in the past (Ampage years ago?) the overdrive channel had it's own tone control section.

To add about tube amps I heard a old metal face mark 4 50 watt  that was worked on by Ken Fisher(what I was told I am in NJ so this could be true) On a 1960 with green backs.

WOW what a sound when it was turned up.

Tube amps could be the PI and outputs and transfomer just hitting this certain power level, clipping and the distortions just making that SOUND.

[tcobretti]

What about the ROG matchless (matchbox) is it as touch sensitive as the other ones.
Cheers
Rafa

I haven't built the Matchbox, but I suspect it's like a higher gain version of the Vox, which is essentially what a Matchless amp is.  So, probly less touch sensitive with the gain maxed; however, if you back off the gain it's probly good.  For me, the biggest thing is whether you want the Vox style EQ or the Matchless style tone switch.

[markm]

The English Channel is a real nice one indeed.
Gotta be one of the best ROG circuits IMO.

[MartyMart]

some good posts in this thread

I am not again the JFET circuits they can be cool and IMO are their own sound.

IIRC there was a dumble schematic or two on the web in the past (Ampage years ago?) the overdrive channel had it's own tone control section.

To add about tube amps I heard a old metal face mark 4 50 watt  that was worked on by Ken Fisher(what I was told I am in NJ so this could be true) On a 1960 with green backs.

WOW what a sound when it was turned up.

Tube amps could be the PI and outputs and transfomer just hitting this certain power level, clipping and the distortions just making that SOUND.

I bet it was !!
Would it make ANY sense Gus, to throw an amp sim up against a small "audio transformer" at the back end ?
Or something to induce that OT type compression/slight breakup ( I know we have stm's speaker sat simulator too )
It would have to be set up to only come on at "higher" gain/vol settings ,,,,, ?

I'm probably talkin' crap - just thinking out loud
Happy Thanksgiving to all the US members

MM.

[Doug_H]

They sound more tube-like than

...

This is the second time in a week I've seen a comment like this. No one responded the first time so I'll try again. What do you mean by "tube-like"? I would like to see explanations of terms like "tube-like", "tubeyness", etc, etc.

I've played around with a lot of my own ideas using JFET circuits to mimic popular tube amps. I suspect it is like R.G. said at the beginning- it's the EQ that is the real attraction here, not the distortion, or what device-type it supposedly sounds like, etc. In fact I believe most people wouldn't be able to discern device-types in 2 different circuits in a blind test. There are just too many variables involved in what sounds "good" to people.

The JFET pedal circuits sound good. They do mimic certain aspects of the amps they are inspired from (esp due to the EQ-ing I believe) but I would not call them "emulators". And yes, I think words are important. Text-based internet communication tends to either minimize the significant or maximize the trivial. So I think its important to be clear about what we really mean.

[MR COFFEE]

In fact I believe most people wouldn't be able to discern device-types in 2 different circuits in a blind test. There are just too many variables involved in what sounds "good" to people.

Don't ask me where I saw it, but I recall several times where a recording engineer had asked professional recording musicians to see if they could tell which track was a recording from the mic'ed Marshall tube amp and which was the output of a Marshall amp simulator, and they COULDN'T tell which was which.

But I have seen other "studies" where musicians COULD tell which was the output of an actual tube amp, and which was an EQUAL LOUDNESS HI-FI AMPLIFIED emulation, while blindfolded - WHEN they were playing a guitar through the amp live.

Of course, it's hard to say whether that was due to the presence of artifacts of the amp switching circuitry, tweeter reproduced hiss vs 12 inch speakers, or whatever other largely unimportant tonal factors - or really due to sonic differences in the actual amp "sound" or "feel", or just a lame emulation. The "studies" try to be semi-scientific, but that just isn't very easy to do.

FWIW, I know that when I've played a good tube emulation through a good sound system turned up loud like a Marshall, it sounds and feels a helluva lot like playing through a Marshall stack to me.

I do share some of the concerns expressed here about just dropping a JFET into a tube preamp circuit and expecting it to be a convincing emulation of the sound of that particular tube amp model. The EQ isn't even comparable to the tube circuit if the amp uses lower value caps for cathode bypass to boost the highs - because it isn't the R-C product that sets the EQ ,it's the transconductance of the tube and the capacitor value that determine the frequency response.

[Mark Hammer]

In some instances, what people mean by "tube-like" can refer to how they conceptualize the distortion properties of a solid-state pedal vs those of an overdriven tube amp.  IN other words, they are saying "I like the way a tube amp breaks up, and I wish I could get that in a pedal but they are usually too buzzy or intense".  So, it is kind of a mélange of both distortion amount/intensity and EQ/contour.

[tcobretti]

They sound more tube-like than

...

This is the second time in a week I've seen a comment like this. No one responded the first time so I'll try again. What do you mean by "tube-like"? I would like to see explanations of terms like "tube-like", "tubeyness", etc, etc.

I've played around with a lot of my own ideas using JFET circuits to mimic popular tube amps. I suspect it is like R.G. said at the beginning- it's the EQ that is the real attraction here, not the distortion, or what device-type it supposedly sounds like, etc. In fact I believe most people wouldn't be able to discern device-types in 2 different circuits in a blind test. There are just too many variables involved in what sounds "good" to people.

The JFET pedal circuits sound good. They do mimic certain aspects of the amps they are inspired from (esp due to the EQ-ing I believe) but I would not call them "emulators". And yes, I think words are important. Text-based internet communication tends to either minimize the significant or maximize the trivial. So I think its important to be clear about what we really mean.

Without looking, I'm pretty sure I said earlier in the thread that I agreed that much of the character of an amp sim is the EQing of the circuit.  If I didn't say it earlier, let me say now that I agree with you guys in this.  However, the tubiness manifests itself in a tiny bit of compression that I hear in the circuit as well as their extremely touch sensitive nature.  Most SS preamps aren't touch sensitive at all, so for that reason alone I would describe these pedals as tubey.  Even you if set these to be on the edge between clean and dirty you can still hear the tiniest bit of compression that the circuit introduces.  That touch sensitivity combined with EQing that is very similar to the amp the pedal is based on makes a great sounding pedal that is very reminiscent of a classic tube amp.  Yes, they absolutely are not a substitute for the real deal, but for a DIYer without the money to buy a nice amp they are a great solution.

I have never built a sim not using jfets, so I am not saying that they are a better choice than an opamp or any other component.  But these jfet based pedals sound great and strike me as sounding tubelike, at least, more so than most distortions.

[Gus]

Another Hint

Look close at  musicman amp schematics

Often one of the opamp gain stages has an interesting transistor resistor section of the feedback network

Musicman amps had some cool well thought out circuits.


http://www.drtube.com/guitamp.htm#MusicMan

And years ago R.G. had a cool mystery circuit fragment from a VOX solid state amp(s0

[Phorhas]

Yeah- I tried the MusicMan thing a couple of times, I didn't hear much difference. I think it also has to be done on a bigger suppky voltage than 9v

[Rafa]

Yes, they absolutely are not a substitute for the real deal, but for a DIYer without the money to buy a nice amp they are a great solution.

I totally agree

I have never built a Sim not using jfets, so I am not saying that they are a better choice than an opamp or any other component.

I think you should try the LXH2 Marshall simulator, If it seems too complicated you can omit the cabinet simulator, (I haven't the cabinet simulator)
The sound clips are my page are not really good (I was in a hurry whren I recorded them), but when I finish my exam period Ill probably record new soundclips.

Cheers
Rafa

[idlechatterbox]

QUOTE:
"This is the second time in a week I've seen a comment like this. No one responded the first time so I'll try again. What do you mean by "tube-like"? I would like to see explanations of terms like "tube-like", "tubeyness", etc, etc."


A typical argument in the tubes vs. SS/chip amp debate:

"nothing sounds like a tube amp. You just can't match the 'warmth' that tubes give the tone...."
"yeah? Well, what's this 'warmth'? exactly?"
"what's 'warmth'? Dude, that's the tone you get from a tube amp!"


Another interesting series involves sneering at anything that's not a 1960s Marshall, and then claiming that no SS amp can hope to come close to that sound. The tube-advocate usually omits the fact that very few TUBE amps can come close to that sound.

In the interest of full disclosure, I own tube and non-tube amps, and like both kinds. Nothing high-dollar, mostly because my playing is low-dollar and music isn't my day job. My ears aren't oscilliscopes, but they tell me that with the right effects chain, speakers, etc., it is very difficult to tell the difference between a tube amp and a modelled/emulated SS amp. I won't say impossible, and I've only heard the world through my 2 ears (such as they are), but very difficult. Again, I don't deny that tube amps are cool; they are. But I've yet to hear (maybe the key word) a convincing case that what makes them cool is a tone that nothing else can approximate.

From an economic standpoint, it seems to me that it's also relevant to look at the debate in terms of the scale of any differences, if there are any. In other words, there may well be some audio "distance" between a reasonably priced SS amp and a tube amp. But this has to be set against the distance that separates a new set of strings from an old set, mods to the speaker cab, the various tone-boosters available on this site, etc. At least some of the people sitting around lusting after tube amps could enjoy a similar step-up in tone quality if they would just swap out the speaker or buy new strings, but there's not a lot of cachet in talking about that.

Have a good weekend everyone 

[Gus]

idlechatterbox

Posted a good point.

Speakers.  You want to have some fun take a small practice soild state anp and connect it to a good set of speakers.  A two x12 or a marshall cab or.........................................

[Tobias Karlsson]

idlechatterbox

Posted a good point.

Speakers.  You want to have some fun take a small practice soild state anp and connect it to a good set of speakers.  A two x12 or a marshall cab or.........................................

Gus is absolutely right about that!

When I put one of my works crappy Marshall Valvestate through my own 4x12" Marshall cab with old "greenbacks" they sound amazingly cool.
On the other hand, when I connect my old Marshall's to the speakers in the Valvestate it sounds VERY mediocre! Something to keep in mind, the speaker cab have a HUGE impact on the sound, sometimes I think much more than anything else, mics, distboxes, preampss etc. Not that they don't change the sound....

Tobias

[DDD]

IMO the general reason (or the Holy Grail) is hidden in the interaction of the output (tubes + transformer) stage with the GUITAR speaker.

[alfafalfa]

IMO the general reason (or the Holy Grail) is hidden in the interaction of the output (tubes + transformer) stage with the GUITAR speaker.

Exactly right DDD, my criteria are: is the emulation capable of producing something that sounds like the perfect crunch sound.
This has to do with harmonics happening and a speaker compressing ( and distortion slowly setting in).
The OT contributing with certain a certain colouring of the signal.
It's all very complex.
The sound  I like for example is the guitarsound of Tom Petty and his frontman Mike Campbell; mainly Voxes and small fender amps I read.
An amp emulation will need to helped by either a speaker simulator or like some people suggested by an OT and  an Alnico speaker.


Alf

[markm]

This is a very enlightening topic indeed.
Hot for sure but, enlightenting never-the-less.
Check my current avatar.....that's all one Really needs to sound Awesome

[tcobretti]

This is a very enlightening topic indeed.
Hot for sure but, enlightenting never-the-less.
Check my current avatar.....that's all one Really needs to sound Awesome

I bet it would sound even better with a Fetzer Valve in between!