FYI (New Article) Modelers & Live Guitar Amplification

Kewlpack

Mike (G3456) has written a good article that goes into the details when using MFXs and traditional guitar amps in a live setting.

Thought you guys might enjoy the read.
http://www.thestompbox.net/ViewArticle.aspx?ArticleID=36

ACWild

Great article, thanks! I love your site. 8)

0Dannyboy

Yea what a Kewl sight and great info. 8)

Kewlpack

'preciate it! 8)

philflood

This is an excellent article. To me, it was great for getting across the idea of modeling. Its kinda like using e-drums vs the real thing. E-drums can sound very very good, but they will sound different from their real counterparts. Drums are much less complex than tube amplifiers. To expect modeled sounds to be the same as their real counterparts, is expecting a bit much. But, we can get close, and we can get something that sounds real good!

hodge

Great insight and layman's explanation. Another point on perception, if I may.....A piano only sounds like a piano when you're in it's presence. All recordings analogous to that sound require the mind to \"suspend it's disbeleif\" in the genuinity of that sound. It's true of all audio recording. The world's greatest performing amps heard live, stand head and shoulders above any rendering recorded by the world's greatest audio engineers of those same amps........Is it live or is it Memorex...We'll always know the difference.

Hodge note : I'm pleased to be born in this time of near \"limitless tools of expression\". Still reading more than I'm playing right now....some difficulties, but this site has proved invaluable to get me through the toughies........I appreciate the candor and the personalities found here.

Mike B

Thanks to Kewl and G3... Good article, not too techie and gives me a good idea of what's going on in my amp with all these models. Thanks!

groovy

Interesting article

But with some major points I could not understand.

For example,

A) \"chimey 3 stage sound of a Fender\"

But we can design a 6 stage preamp that sounds like Fender.

And we can make 3 stage amplifier that dont sound like a Fender.

and we can have a MFX unit with 20 stages that sounds like a Fender

So what exactly is the link between \"3 stage\" and \"sound of a Fender\" ?



\"brittle Gain attack\"

Google has no hits for \"brittle Gain attack\"

and \"Gain Attach\" is something to do with Video

What exactly is \"brittle Gain attack\" ?

and what has it to do with exactly 6 stages


Is it not possible to have the same sound with five or seven stages ?


If you have a word that exactly describes the number of stages of an Amp, please help me populate my list :


1= ?
2= ?
3 = chimey
4 = ?
5 = ?
6 = Brittle gain attack
7 = ?
8 = ?
IC with 100,000 internal stages = ???



C) The whole article revolves around the central theme that the number of gain stages determines the tone. This is overtly simplistic and suitable for explaining how Amplifiers work only to very young musicians.

How can we explain the following :

i) It is possible to design a 10 stage Pre-amp that is totally linear with no distortion.

while it is possible to design a 1 stage pre-amp with as much distortion as you need.

ii) different amps with the same number of Stages still sound different

iii) FRFR Amps with 5, 10 and 15 gain stages still sound the same

iv) I can change the tone controls on my Amp and it sounds different. But Hey, the number of the gain stages remain the same and you claim this is what determines tone.



D) \"Our Fender 3 stage must now accommodate 5 stages of gain.\"


I just cannot understand that sentence from a technical viewpoint.

The two external gain stages could have a gain of 0.5 in which case they actually reduce the signal level.

or they could have a gain of 1 which means that the following Amp does not see any change in signal level

Whats there to \"accomodate\" here ?

I hope G3456 is not refering to building the TS9 into the Fender box. Here I can readily agree that the Fender 3 stage Amp might not be able to accomodate some extra gain stages due to space restraints. But from an Electrical Enineering perspective, that sentence above does not make any sence.


E) \"You can add a TS9, but you will have to keep the TS9 gain output much lower than what you had dialed in for the Fender.\"


Oh Oh,

We seem to have confused the gain control with the output level control here.


Is it not possible to increase gain and reduce output level ?

Why have we only the option of reducing gain in case our Amp has more stages and not the output level of our distortion box ?




Most Screamers are made using ICs. As per the article, we will surmise that this always ruins the sound as it adds 100,000 gain stages before the Amp which the Amp obviously cannot \"accomodate\" as it was designed for only 3 or 5 or 6 stages ???

But reality tells us otherwise !!! There are a few million of us happilly using 100,000 stage Tube Screamers in front of all types of Amps.

iliace

It makes sense when you consider the target audience. 1% of people (if even) will bother to understand such technical details, even superficially.

Kewlpack

Since G3456 wrote the article, I'll defer the debate over technical details to him. I suspect there may be a terminology gap between the two perspectives (?).

guitar3456

I've learned never to respond to groovy, or whoever he is on which day!

groovy

\iliace\ wrote:

It makes sense when you consider the target audience. 1% of people (if even) will bother to understand such technical details, even superficially.

Then the rest 99% are legal prey to those who try and sell products wrapped in pseudo-science that cannot stand even the slightest questioning.

As always Caveat Emptor. You believe anything you are told without asking basic questions, you deserve to get gypped !!!

If this article was posted on WIKIPEDIA, it would be ripped apart due to its technical inaccuracies in no time at all.

G3456, Want to take up my challenge and repost on WIKIPEDIA ?

ne1roc

The secret to groovy's success!

thehootman

Lol.
does Groovy or G3456, or anyone for that matter, have a degree in electrical engineering? If you dont, well I thing that 3456's explanation is quite adequate. If this explaination works to get a good tone, then its correct. EG scientists havnt proved that atomic theory is reality - its still atomic theory - no one has seen an atom. Just the same, we dont really know to full reason behind why tube amps do what they do.

P.S. - if you know exactly why, please mail me a 10 000 page report on the matter.

:P

zap

Tom Scholz found \"If you kick up the signal in front by 3 or 4dB, and start boosting the highend at around 2kHz around 6dB per octave, you can get the signal to noise ratio down to a usable level.\" http://members.aol.com/teapartybo/guitarplayer877/index.htm about in the middle of the article.

In his mutiple gain stages then he now had room to tweak his tone without overpowering noise. If you think his analog recordings were great, check out the digital remasters. www.bandboston.com under NEWS.

iliace

When people ask me questions about music theory, I always want to go in-depth... mathematical relationships of intervals... overtone series (ne1 knows this!) ... conic sections representing ratios of intervals (and, interestingly enough, planet orbits in the solar system). Most people who pose the question, however, don't really care about all of that - they wouldn't bother to understand it even if they could pick it up. So, showing the major scale and chords built on it is much more effective.

Again, target audience. I can't think of a circumstance where you would want to provide information that is either unused, unuseable, or both.

ACWild

\iliace\ wrote:

When people ask me questions about music theory, I always want to go in-depth... mathematical relationships of intervals... overtone series (ne1 knows this!) ... conic sections representing ratios of intervals (and, interestingly enough, planet orbits in the solar system). Most people who pose the question, however, don't really care about all of that - they wouldn't bother to understand it even if they could pick it up. So, showing the major scale and chords built on it is much more effective.

Again, target audience. I can't think of a circumstance where you would want to provide information that is either unused, unuseable, or both.

I did get the impression that it pained you to dumb down the theory questions that were popping up.

iliace

\ACWild\ wrote:

\iliace\ wrote:

When people ask me questions about music theory, I always want to go in-depth... mathematical relationships of intervals... overtone series (ne1 knows this!) ... conic sections representing ratios of intervals (and, interestingly enough, planet orbits in the solar system). Most people who pose the question, however, don't really care about all of that - they wouldn't bother to understand it even if they could pick it up. So, showing the major scale and chords built on it is much more effective.

Again, target audience. I can't think of a circumstance where you would want to provide information that is either unused, unuseable, or both.

I did get the impression that it pained you to dumb down the theory questions that were popping up.

But it's a good exercise

P.G.Shadow

Good read guys, made sence to me.
Nice site Kewlpack. Had a little sniff around after I read the article.

Keep Rock'in P.G.

groovy

\thehootman\ wrote:

Lol.
does Groovy or G3456, or anyone for that matter, have a degree in electrical engineering?
:P

Maybe thats the problem,

Not too many technically inclined people over here. Iliace guesses less than 1% of the audience here wants to get into technical nitty gritties. I reckon 2%.


Hey G3456, I am sure you would want your article to be technically accurate. Dumbing down is not the same as purposely introducing errors and misunderstandings.

You would also want your article to reach out to more people.

So I think I will repost your article at WIKIPEDIA where there are many more EE's than here. Lets see what they say when they have a read.

If I dont hear from you in the negative, I suppose I have your OK to repost at WIKIPEDIA.




And in the meanwhile, I request the forum members to try some experiments to find out if 3 stage amps = Chimey and 6 stage amps = brittle.

A) play with the tone controls of your amps. Hopefully you will find a change in tone even though the number of stages remain the same.

Reduce the level control of your MFX or stomp box. Hopefully you will find that you can use high gain if you reduce the output levels. All this even though the number of gain stages in the MFX+Amp remain the same.



PS : Iliace, I would be VERY interested to know about the link between planetary orbit ratios and musical intervals. And if all that is somehow linked to Fibonacci, wow !!!

groovy

> Any open back cabinet is brighter sounding in both midrange and high frequency.




This appears to contradict generally accepted principles.

Open/closed back cabinets only affect signals below 800 Hz as per the work of respected scientists in this field. A choice of cabinet should not have an effect on the Midrange and high frequency response as per work by Thiele-Small.

Most cabinet design software dont even bother to show Mid and high response as the Cabinet only changes how the bass responds. Here are two examples :







High frequency response is determined by the Tweeters

Tweeters are normally self enclosed

You get the same High end response from a tweeter irrespective of if you mount it on a Open or a closed cabinet.

thehootman

How are intervals linked to planetary orbits????
Bear in mind that planetary orbit are ellipses, the plantet wobble as they go around, are centred around the sun, slow down when they pass another planets etc.

Or do you mean Kepler's Law
Ta2 / Tb2 = Ra3 / Rb3 - The squares of the periods of the planets are proportional to the cubes of their semimajor axes
?

(I'm into maths )