Make your own free website on
Terry's Music site -  Barefootterry  |     home
back to  Terry's Music site -  Barefootterry
mail 1.25

yep, my set up circa 2005 after simplistic cut back.
ok i got a few more this is from 2007

 Harmonics    Generated by  Tube and Solidstate amps
see EQ for amp sounds    E.Q. & Tubes vs SS

The widths of the fundamental and the harmonics, are pretty much the same. For the most part, because I'm using pure sine-waves to derive this data, the sidebands are low enough (on the order of 100 times) to be discounted out of the equation and counted as noise floor. During no measurement were the sidebands at a level that could be counted. The harmonics generated, by the distortion, were pretty much a single spike on the RTA.
In fact, the values that I provided, in the example below, already took that factor into consideration, i.e. all power under the 1/24 octave intervals that I used for sampling was integrated, for both tube and solid state. Even order-harmonics are, generally, at a much higher power level in tube-based gear than in solid-state-based gear.
I would agree with you, though, that if I were using a guitar or a complex audio source, as an input, I would need to integrate the area around the fundamental, and the harmonic, to determine overall level(s) in each area. However, that said, you're, typically, going to end up w/ the two or more fundamentals and their respective harmonics all spread out... and then the sum/difference frequencies and their harmonics spread. In most cases, the harmonic content/structure is still the same, tube versus solid state, you just have a lot more data to stare at on the analyzer.
Interesting, too, that you bring up the design issues, as well. The newer tube amps are designed to be much more linear than the older ones. They don't distort as nicely because they're smack in the middle of their load lines, rather than biased one side or the other. They're much more accurate. The tubes, too, are made to tighter specs w/ less HF leakage. All of this has made the newer tube amplifiers sound a little more "tinny" (listen to the difference between the old Fender Twins out of the 60's and the new ones, today). They're generating more odd-order harmonics... due to the fact that they "tightened" things up a bit in the overall design.

I'll add a few comments in here and then run. I've been doing spectral
analysis on tube amps, distortions, distortion modelers and a bunch of other
stuff, just for own edification, recently. So, rather than spend time w/ a
bunch of theory read in a Gerald Weber book, I'll set out what I've actually
learned through some pretty in-depth testing and research on this type of

Solid State distortion, as many of you have probably read in the "tubes are
better rags" is somewhat different in harmonic content, structure and
makeup. Basically, what this means is, it sounds different.

Most tube-amp references would have you believe that tube amps generate more
even order harmonics and solid-state's generate odd-order harmonics. That's
crap. If you do the math, odd-harmonics can and do exist. However, if you
take even order harmonics out of the picture, the fundamental can no longer
exist, either (and that's the note that you played, originally).

In reality, distortions have the following characteristics:

Even-order harmonics (2nd, 4th, 6th, etc) are fundamentally lower in power
than the odd-order harmonics. This is true in BOTH tube and solid-state

The spacing of harmonics will be multiples of the fundamental frequency
played. Thus, if your note was 150Hz, all harmonics will be spaced 150Hz
from each other.

The doubling of any frequency is an octave.

All harmonics are related by "frequency".

The level of each harmonic determines the "timber" of the instrument (not
the pitch). Timber is the way we differentiate different sounds. Marshall
amps/cabinets emphasize different harmonics than say, a Fender Twin being
driven by a Pro-Co Ratt. This difference in harmonic levels changes the
timber of the instrument, thus allowing us to hear different sounds for the
same input "tone", or fundamental frequency. That's also what makes the
difference between the sound of a guitar and a violin playing the same note.

Harmonics are all mathematically related to the fundamental (in other words,
you can take the frequency of a harmonic and divide it by the fundamental
frequency and come up w/ a whole number (no decimals).

Let's look at a short range of harmonics generated by a 150Hz signal being
overdriven. This applies to both tube and solid-state distortions.

150Hz - Fundamental
300Hz - 2nd Harmonic
450Hz - 3rd Harmonic
600Hz - 4th Harmonic
750Hz - 5th Harmonic

The 2nd, 4th, 6th, etc. harmonics are called even harmonics.
The 3rd, 5th, 7th, etc. harmonics are called odd-harmonics.

To get the full-range of harmonics generated you can keep adding 150Hz to
each result, as shown above.

The unique thing about solid-state distortion is the fact that even ordered
harmonics are at a much lower level. For example, when I did a quick
spectral analysis of a solid-state distortions in the RP12 being driven w/
150Hz, the difference between the 150Hz and the 2nd-order harmonic was about
50dB. The 3rd Order and 4th order harmonic difference was nearly the same.
The only difference, between these distortions was the amount of HF,
upper-order harmonics that got added to the overall sound. The ratio's of
the lower-order harmonics remained the same when I backed off on the levels.
Just the amount of high-order harmonic content changed.

Tube distortion is different. I sat and measured this on a couple of Fender
amps I've got. A Hot-Rod Deluxe and a Deluxe Reverb. They both had the
same results. Interestingly enough, my POD model of the Deluxe Reverb did
nearly the same thing.

In tube-based amplifiers the even-order harmonics are much closer to the
fundamental and the odd-order harmonics. There was only about a 25-30dB
difference, on the tube amp, versus a 50dB difference on the solid-state
gear. This variation (higher levels of even-order harmonics) occurred across
the entire spectrum.

Also important to note, at this point, that overdriving a tube amp, harder,
has the same effect of adding more and more higher order harmonics to the
sound. Backing off on the thing removes these... the same as solid-state.
The difference is the relationship between the even/odd harmonics.

Another important thing to note is that as the harmonics get higher, they're
going to sound more and more like the noise floor (that hiss you hear when
you turn your amp all the way up). The levels are random and they're
spaced very close together. Random fluctuations and close-spacing of
frequencies, well, that's noise!

I go through all of that to bring us to part of the reason why tube amps
stand out a bit more on the stage... In the studio, with creative EQ,
multi-band compression and other things, we can compensate so much easier.

As noted in a lot of the previous e-mails, human beings and clothing, etc.
that fill a bar are high-frequency absorbers. They literally suck the life
out of the top-end. Having worked as a sound man for a while, you have to
compensate by making the mix a lot brighter, as the crowd gets larger, just
to deal w/ the HF loss.

The second issue that we're dealing with is the background noise. As more
and more folks come into the club, talking, moving, etc. they're generating
a HUGE amount of random noise patterns that ends up being similar to pink
noise - which masks most sounds. Because much of the noise is in the
audible range, and much of it in the guitar range, we're masking some of the
sound, just due to the ambient noise generated by lots of folks walking,
talking, drinking, clinking, etc... (for a demonstration on how pink noise
masks sounds... turn on a fan and listen to a tape, or, turn a boom-box
tuned between two stations up and try to listen to another boom box right

Here's the point. The even-order harmonics are CRITICAL... as they are
lower in frequency than odd-order harmonics. Solid-states emphasize
odd-order harmonics and they have a higher frequency component that tube
sounds. That's why we're losing some of the sound in the crowd. Tube amps
bring up the levels (they don't actually emphasize them over the odd-order
harmonics) of the even-order harmonics, thus giving a bit more "power" to
the sound, overall, in the area that we can all hear at, nearer the
fundamental. A sweepable mid-range, on the mixer, should also help out with
this. They can set the Q and frequency range on it to be approximately
where you play the most so that the harmonic content, closest to most of the
fundamentals you're playing, comes through.

Adding a little "edge" to the guitar in the 2.2kHz to 2.5kHz range will make
it stand out in the mix, no matter what type of distortion you're using.
If you have a rhythm guitar player that's also playing w/ distortion, set
your boost in the 2.2kHz range and give your rhythm guitar player the 2.5kHz
(that usually works out very well). It keeps your fundamentals and
even-orders a bit stronger.

Another method to combat this "problem" w/o buying a new amplifier is to use
an Enhancer/Exciter. These boxes actually add harmonic content to the
material. If you get a box that does both, you can mix the levels, as
needed, to get the right balance between even/odd ordered harmonics.
Enhancer/Exciter gear, now, can be obtained for about $150.00. Plus, it has
the direct effect of adding extra clarity to both clean and distorted sounds
w/o muddying things up. They work great and are the cornerstone pieces of
gear on both studio and soundstage.

I hope that this has helped you guys out, a bit. I've been getting pretty
deep into studying this whole spectral signature thing and I find it
fascinating. The darned thing is, I'm still learning... This is sort of a
"chapter 1" in this stuff.
Have a good one. Questions/comments, please ask.
That is very true. But you forgot to mention the width of the fundamental and harmonic signal. If you integrate the peak you can get the power included by each order.
So it is not only the type of the intermodulating products you will get but some more other characteristics for the sound.
Generally you will see that tube amps are not longer used in systems just because they add a big level (dB) of harmonic. BUT this is sometimes good for the quitars where you can get a rich and warm sounding.
When you saturate a tube you will get a much higher levels of sound that a semiconductor amp. It is the summation of the integrals of the spectrum components.
But there are sometimes different amps(tube) that the power level of the harmonics are not linearly decreasing with frequency. In that case you get different type of sound characteristics. For e.g. your 3rd order harmonic can have higher power than the 2nd.
So it is more about design issue.
Engineers do not like working with tubes. They like transistors as they have a better signal to noise ratio. But if you play hard core and stuff you want the opposite one.
That is when you have to choose an effect. It is more about if the design characteristics match with your needs.
Excellent work Darwin and Mounasgelaki (sorry but I didn't see your name) !

Now, although I can follow what you guys are discussing, I won't pretend to have any real expertise in the technical department here so please feel free to correct me if I'm way off base.

The only thing that seems to be missing here, or just to flesh out (so to speak) the topic of this discussion is perhaps the "human" factor when comparing solid-state to tubes. Again, the end result is purely subjective as the listener can decide what sounds good to him so before you write me off as another "tube ownz" guitar-head just keep in mind that I can only really speak for my own experience as vast or limited as that may be.

Anyway, I get the impression that your tests have likely involved analysing the spectral characteristics of a single tone through these amps for the purpose of scientific comparison, however, guitars are played in real time in three dimensional space which I don't think can be discounted entirely. I'll just list my points below:

The guitar signal going to the amp often is a signal comprised of multiple strings (chords obviously and such) and other noises (muting, etc.) which affect the response of the amp and can't be totally written off as simply the characteristics of a particular guitar. Tube & SS amps will react differently to these signals.
Volume, including the attack of notes and guitar volume has a completely different effect on tube amps than solid-state. I don't exactly know how technically (maybe you guys can tackle that) but I know when I play softer on a tube amp or at lower guitar volumes the sound responds way differently.
Feedback is quite different as well. Again, I can't put it into words but it sounds more natural on tube. It almost plays itself. :)I suppose it would be pretty tough to scientifically analyse the same person playing the same thing in exactly the same way on both tube and solid-state (in real time) but I think there is a physical difference (varying voltage as you play?) between tubes and amps beyond the spectral characteristics you describe. Again, it's just...different.
Well, I just thought I'd throw that into the mix and see what you guys think. :)
Steve Rollins
You'd asked about a comprehensive volume on EQ and how it works... well, there's a lot to that, actually. If you're looking for a general overview, Sound on Sound magazine ran an article last month and is running another, this month, on that very topic. In fact, I think, they're going to be running a few more articles in the series.

If you're looking to go into this thing in depth, the best thing that I've found is the "Golden Ears" program. This thing is written by David Moulton and is a series of 8 CD's (if I remember right) that take you through EVERY aspect you could ever dream of w/ regards to EQ. It's in-depth and each CD is about 74 minutes of lecture, exercises and time. The thing even comes w/ workbooks. If you're not into being very advanced about EQ, I wouldn't suggest spending a lot of time w/ this one. But, if you want to be a master at it, by all means, get this series.

Now, more focused works, if you will:

It really depends on the topic of EQ that you're looking to cover. Here are a few books, that I have, or have read, personally, that I've found to be quite helpful. To date, I've found, unfortuneatly, no single treatise on EQ, other than the "Golden Ears" series. The rest of it I've found scattered in bits and pieces in 100's of various books on the subject.

If you're just looking for guitar gear EQ tips, tricks and ideas, here are some good references:

The Recording Guitarist - A guide for home and studio
Jon Chappell
Hal Leonard
ISBN 0-7935-8704-2

This book is easy to read, discusses a lot more than just guitar EQ, including gear setups of a few folks, some interviews w/ guitarists as to how they got their sounds, etc. It's not very technically written, but easy to understand w/ some good information about other effects, as well.

The Audio Pro Home Recording Course - Volume 1
Bill Gibson
ISBN 0-918371-10-4

If you're going into recording this entire 3-book series is a MUST read for everyone. Written in a non-technical, in-depth way, this bugger covers EVERYTHING from studio setup, gear, recording/mix-down/bouncing techniques, through to mastering. It's authoritative, well-written and this stuff works!

Book 1 covers guitars, guitar EQ, guitars direct, guitar signal chains and a bunch of other stuff that works both in the studio and on the stage. Book 2 covers vocals, bass guitar, pianos, etc. Book 3 covers mix-down and mastering technique. EQ and effects specific/unique to each instrument is covered in their respective chapters. And yes, each instrument type has its own chapter in this series.

The Art of Mixing
David Gibson
Hal Leonard
ISBN 0-918371-17-1

The title doesn't necessarily imply that EQ is a part of the overall subject matter, but it is. While this book is dedicated to teaching a person how to mix-down recorded tracks for burning, the information, here, readily applies to a variety of different situations, including the live sound-stage. Loaded w/ tons of full-color pictures, this thing will have you thinking about how/where you sit in a mix faster than you can say "mix". Very well written. If you're looking for in-depth EQ-specific information, this book isn't going to give it to you, but EQ as a whole, in relationship to a song and all instruments, this is very good.

The Musicians Guide to Home Recording
Peter Mclan and Larry Wichmann
ISBN 0-8256-1378-7

This book is CHOCK FULL of EQ settings/ranges for various instruments. In fact, that's the only reason I have this book is because of the information on the EQ settings for various instruments and their ranges. Doesn't really explain to you why it works that way, but they do, at least, give you the information that you need to make it work.

Total Recording
David Moulton
KIQ Productions
ISBN 0-9674304-0-2

This book, if you're looking for hard-core, how it works stuff, is going to be the bomb. You'll even be able to figure out, after reading this, the problem frequencies that you're going to face in every club, just by looking at the dimensions of the club, and how to compensate for them. This is a companion to the "Golden Ears" series that I'd mentioned above. This book, however, does not specifically focus on EQ for various instruments, instead, it gives you the highly technical details about EQ and it's operation so that you can apply it any way that you want. Plus there's a ton of other useful and technical information that you're not going to get any where else, that I've been able to dig up, thus far.

Hope that helps. If you have further questions, let me know.
I thought long about posting this, cause I think it answers it self, and its
not a joke. But....
In analyzing the harmonics and waveforms, has any work been done, on these
odd/even harmonics and the effect they have on the human ear. Meaning, does
the ear discriminate between the two? would an even harmonic cause a
different response by the ear. Do different sizes and shapes of the ear
prefer different combinations of these odd/even harmonics. They must
we hear them, but does the ear "like" one over the other? does our physical
make up, size/shape prefer one over the other?
Mine likes the sound of old tube amps . :)
hey thanks, you guys are amassing. Ive printed almost every one on the
"crowd" series.
Darwin thanks for the heads up on the 6 kHz. That was right on the mark.
<> barefootterry

Shape of the ear?
With response to your question, there have been, to my knowledge, no real "tests" done, that we're highly subjective in some way, shape or form about the sensitivity of the human ear to variations in harmonic content/levels. As in many applications, the determination of what "sounds good" is in the eyes of the listener, rather than in the content of the harmonics, at times. Plus, I've been able to creatively EQ solid-state distortion and it's hard to tell the difference, once you've done that.

Even/odd harmonics, we know, are processed in fundamentally the same manner, by the ear (given that they're at the same frequency - which, in terms of the original signal, require a frequency change). There isn't anything different. So, a 3rd order harmonic at 1kHz would sound, if we could isolate it, the same as a 2nd order harmonic at 1kHz, again if we could isolate just the harmonic.

What we percieve as timbre is the balance and distribution of the harmonic content of a signal. The timbre of a tube amp basically means that even and odd harmonics are at nearly the same level, when the thing gets overdriven. Solid state amps, when driven to the same level of saturation produce even harmonics at a lower level that odd harmonics. You can tell the difference, because, of course, the timbre of each amp would be different, given the same listening room, speaker cabinets, apparent volume and EQ settings.

Many of us, who are trained musically, and some who are not, will be able to determine the difference in timbres. There are some that are what we could call "tone-deaf" that either can't distinguish, or just don't care, between the two. They just haven't picked up on the differences.

Could I be more vague and yet try to answer you question? The answer, truly is that I haven't heard of any "real" studies being done on the ability to tell the subjective difference(s) between the two types of distortions. However, most claim that they can tell.

see    E.Q. & Tubes vs SS
see Harmonics

This is a really...really silly question...but I will go ahead and ask.
What character of the sound makes the guitar sound differnt than other
musical instruments?

>>> In reality, the actual "power" of the guitar sound is not in the
>>> fundamental frequency, but it's in the harmonics.

What do you really mean by that? Are you implying the overtones
(harmonics) are responsible for this character? I am not good in physics,
but what is "amplitude" of a sound? is it the same is "volume" or
intensity of a sound? What is "quality" of sound? Is it something to do
with the Harmonics/overtones? And is Harmonics and Overtones the same term.
I am planning to write a research paper for my Software Engineering class
about Digital Sound modeling. It shoud be fun, but i have a feeling it will
be painstaking? Does anyone have any websites where I could do some
research about "digital sound modeling"
Thanks :o)
The tone of the guitar lies in a couple of different areas.

1) The resultant fundamental tone, from plucking the string, is, basically,
a sine wave. That means it well-rounded, curved and has a period that is
very predictable. Oboes, for instance, are more of a triange wave. Other
woodwinds have square-wave, or nearly so, shapes.

2) The harmonic content of the guitar is another thing that makes the sound
unique. When you pluck a guitar string the string vibrates along it's
entire length. Let's say that you pluck a Low-E. The combination of the
string guage (how thick it is) and the string length make it vibrate at a
certain rate of speed. Low-E is, roughly, 80Hz (I don't have my frequency
reference charts in front of me this very minute, so we're approximating).

If you can picture the string bouncing up and down 80 times per second, for
a minute (and you can simulate this w/ two folks and a jump rope), if you
could look at the waves leaving the string you'd note that they rose and
fell very "smoothly". You'd also note, looking down that string, that it
appeared to be "divided". In other words, the string was not only vibrating
along it's length alone, but also the string would appear to be "divided in
1/2" and that both halves would be vibrating at twice the speed of the
entire string. Each of those halves would be divided, as well, and
vibrating at 4 times the rate of the full string, etc... Those "divisions"
that are vibrating, seemingly, on their own, are the harmonic intervals of
that string (overtones) if you will.

The fact that the overtones are all bouncing in the same "sine wave" fashion
and that the number of overtones are limited, physically, by string length,
string guage, string tension, the guitar its unique sound - that's
why you can always tell a guitar from a piano, harmonica, etc. Nylon
strings have different laws of physics that govern their vibration (i.e.
different material, thickness, etc) and different overtones are generated.
On certain types of strings, the fundamentals are more apparent (thicker
strings, nylon, etc) due to the fact that the amount of damping (how much
the output is reduced) is greater. On strings that aren't damped as much
(higher strings) more of the overtones are present. How's that for fun?

A piano, because it's using copper strings rather than the nickel-based
stuff that we use on guitars, it's string length is fundamentally different
for the same pitch and the sound board is different is going to sound
different when a note is plucked. The string vibrates with the same laws,
but, a longer string will be somewhat tighter, generating less fundamental
and more overtones... cool, hey? That's why they all sound different.

That brings us to various guitars and thier sounds. Fenders have a specific
string length that Leo gave them back in the early days. That string
length, coupled w/ the wood he used and the design of the overall guitar
body gave it the unique sound it has. Certain woods will damp high
frequencies at a greater rate (i.e. muffle them) than what other woods do.
Thus you have differences in sound between Alder, Ash, Maple, Rosewood,
Mahogony, etc. Les Pauls are made out of different woods, have different
string lengths and hardware, etc. and, thus, damp or attenuate the higher
frequencies at a different rate of speed.
> >>> In reality, the actual "power" of the guitar sound is not in the
> >>> fundamental frequency, but it's in the harmonics.
> What do you really mean by that? Are you implying the overtones
> (harmonics) are responsible for this character? I am not good in physics,
> but what is "amplitude" of a sound? is it the same is "volume" or
> intensity of a sound? What is "quality" of sound? Is it something to do
> with the Harmonics/overtones? And is Harmonics and Overtones the same
Amplitude - For the most part you can think of this as the "volume" of the
sound. Amplitude, for all practical intents and purposes is a level
measurement. Higher amplitude means more volume, lower amplitude means
less volume.
Quality of sound, as I mention it, has to do w/ the overall "balance" of the
fundamental and the overtones, together, rather than the subjective version
"that's a good quality sound".
Hope that helps.
Hello Darwin,
Gosh....Thanks so much for your concern. You really shouldnt have put that
much effort into it. I can understand how hectic can be. But thanks
anyways. I have read your email several times. Yeah things are a more
clear by now. I was more interested in the software aspect of sound
modeling. Yeah you do need a processor (DSP) but the software is there as a
mediator between your sound source and the processor. I have found quite a
bit of information, and even some C++ codes on how software can simulate
pitch, vibration, ambience, amplitude and all other aspects of sound, but
the DSP is there to process it all. Whew....this porject will be very time
consuming....hehe..if I cant make it within the end of the semester, I might
write something about Windows I can BS about it as much as you
want....without even any research ;)
Hey if you are interested...I have compiled some links to review for
later...i think you might find them quite (way too much for me :)
Hey once again thanks a lot for ur help :)
The links:
Agreed w/ the software side of things being a bit more "flexible" than what
the hardware is... the problem w/ software is the fact that every time you
add a single line of code, you have to recalculate the number of processor
cycles taken by that code and change every timing loop in the gosh-darned
program... that is, if you want to keep everything accurate... You can do
it w/ processors... it's just that the coding overhead gets to be very
intensive... There's a lot of math that'll need to be done, in software,
that can be done automatically w/ a DSP ASIC...
 Harmonizer      (get it--Harmon---izer?)
From the Ezboard forum   (Thanks Frank)

Reply Harmony
Hi,Thanks to all responses to previous questions. Here's another one! When you create a harmony patch and set it to, say, Cmaj and a 'third up', what does that really mean? So, if I play non-Cmaj scale tones what's gonna happen? What are the implications for playing this setting live I wonder.
hi, depends on what you are going for.
The blues scale is most useable especialy for beginers. The 1octive up or down is the other good place to start. If the unit has presets check out the Suboct patch, its awesome. for scarry heavy.
A little musical knowledge is useful to get on quite right.
I'm not the most knowledgeable in this, but I'll try a intro to the subject.
To set up the pitch shifter is to already have an idea in mind.
say ,, a 5th in c# minor. im useing this so we can play in E.
All major keys have a relative minor (related to them) so your lead can be played in eighter the key the song is in or the relitive minor.( well most of the time)
I used an 1-4-5 progression This is The basic blues patern In E the 1 is E the 4-A the 5-B.
The relitive minor for the key of E is C#m, so to play a blues in E and solo in C#m you set up your shifter to blues, C#, and minor. And then select oct up or down, or a harmony in a 3rd, 4th or 5th ect... Or course you can also play the lead in Em, so you would set it up that way. or of course in good old E or use just open chromatic( all the notes). but when you go and solo in each key over each chord change , the solo in E or C#m, for A -F#m, for B- G#m.
You can see there are going to be trade offs. also the other different scales are mixed into the fray. In the set up above I was useing the , whats called Blues scale, this is a pentatonic scale with the added "blue" notes. so you can use it for both scales.
There are tons(well a lot) of different scales. about 7 basic..includeing, mixolidion, Iodian ect...Indian, Equiptian, asian,.and the buttscratcher scale (the one I use) .
so sometimes the intelligent shifting is a pain in the butt. but when used effectively, sounds great (for a crappy sound use the up 2nd),. where The hell could a person use that?
so set it up the way I showed above, use up a 5th, and play Robert Palmers "bad case of loveing you" those fills you couldnt play? With the pitch shifter, set this way , your there.
so good luck I hope this gets you in the door to shifty pitches,anyway.
B.Terry - Barefootterry
Frank Genus
Reply Re: Harmony
Hi tmccallquteduau, welcome to the forum.
To use your example, if you play note that is not in the Cmaj scale, the harmonizer will still play a note that's a third above, and it may (or may not) sound ok in the song you're playing. It depends....
Below is a snippit of a previous post I made discussing the RP2000's "Harmonizer" effect. Hopefully, this will help explain my answer to your queston.
- Frank-------
Unfortunately, the RP100, RP200 & RP300 do not have a "harmonizer" effect, only the RP2000 does. They all have the "Pitch Shift" effect, but there's a big difference when trying to play harmonies. In any case, I'll explain both, but be prepared, it's gonna be long!

A "Pitch Shifter" takes your guitar signal, digitally transposes it (based on the interval you set, i.e. a 3rd up or a 4th down), mixes it in with the original note, and plays both back at the same time. While this may sound like it's what you're looking for, it probably isn't. That's because the interval is FIXED. Think of a chord... The simplest chord is a Triad, which consists of three notes... The "root", a "3rd" above the root, and a "5th" above the root. Depending on the key (and scale, but I'll talk about that later) you are playing in, these 3rds & 5ths may need to be "Sharp" or "Flat" for any given root. Since the pitch shifter doesn't know what key you're playing in, it doesn't know when to adjust the pitch of the harmonized note, so it always plays an absolute interval, which means that the harmonized note stays parallel to the original note being played. The result is that your lead sounds like "Chinese" music.

Here's where the "Harmonizer" comes in. Sometimes called an "Intelligent Pitch Shifter", the harmonizer works just like the pitch shifter, but knows which notes to make sharp or flat so it keeps the shifted pitches within the key that you specify. Most harmonized leads you hear in songs today are based on either the "Major" or "Minor" scale. In fact a major scale in one key is usually the minor scale for another key (example... The notes that make up the "C major" scale are the same notes that make up the "A minor" scale). So, all you need to know is what key the song is in, and what scale you want to follow, right? Wrong!

The problem: Most songs tend to drift in and out of the key they're written in (especially during the bridge, where most leads take place). I've never worked with the Eventide, but I'd bet one of the advanced features is MIDI control, so you can change the key setting (among other things) via footswitch. Another issue is that your guitar MUST be perfectly in tune (and tuned to "concert pitch"... 440 Hz for the note A above middle C). This is because the harmonizer needs to be able to interpret exactly what note you're playing and where it fits in the key it's set to. If this weren't bad enough, you need to give careful thought to the notes that you're going to play, because playing a note that falls outside of the scale the unit is set to will most likely sound really bad with the harmony added in.

If all this seems like a pain in the ass, trust me, it is! It basicly means that the harmonizer must be set to a unique setting for each song in which you will use it, and you have to map out your leads ahead of time. If you're not up on your music theory (keys, scales & such), it can be a real headache. You'd have to try out your lead using each key setting (and several scale settings) until you find one that sounds correct. I use it at certain points in leads in several songs we do, and I had to give each one it's own patch, not to mention it took quite a while to get the settings right.
I guess by about now, you're sorry you asked, huh?
P.S. Can you give me an idea of some of the songs where you think Kirk is using the Eventide (I'm not up on my Metallica)?
BTW, here's a link that has great information on triads, scales & keys:
- Frank.

That's what I meant, if you're messing with the amps, as soon as you turn the wheel they all go to a default. So, say you have the rect at gain 10 to clean it up, and you turn the wheel, and look at another amp, say classa, the rect gain goes automatically to 80 or something like that, dirty sounding. You need to put it back to 10 before you save it or it will be 80. And sound VERY different from what you originally had. I hope it's not just my unit doing this!

Shameless Music Promotion...

My unit does this too. It is very annoying. I have the same experience. I was looking for a good tone that matched a song I was learning. I had gain of 50 with Boutique. Then I found out Satriani plays through a Marshall. So I flipped over to the JCM 900 model and bam! My gain poped up to 85 or something. It made getting that ideal tone more difficult. I hope the GNX pedals don't do this. I don't see why the software guys would reset the gain when the model is being changed unless gain is part of their AMP class and when it flips they reload a new structure into the unit.

 Speaker Hum and Other Buzz'es

hey trace the problem to isulate the hum source. Donot use shelded cable for speakers. The load is to much for them to handle and you will fry your amp.
start with the amp, plug other speakers in and see if there(it probaly isnt). then unplug every thing from the amp. If no hum its not the amp. next unplug every thing from the mixer and plug it in to the amp. if no hum check the mike cords ect..if it hums it could be the power supply (probaly its that). or a bad or crummy cord plugging it to the amp. You say hum not noise or his. hums are grounding problems or powersupplies . a fixable condition.
any way something to try
> --- dutch <> wrote:
> > Boy do I feel like an idiot..> >
> > After reading everyone's comments about ground loops
> > and grounding all of
> > the various pieces of equipment together, I
> > remembered that when I plugged
> > in the mixing board ages ago someone had snipped off
> > the ground part of the 3 way plug
> > I replaced the end with a 3 prong plug and the hum
> > has pretty much gone away.
> > Thanks for all your comments and
> > suggestions...sometimes the easiest
> > solutions are the simplest ones.
> > Dutch
- especially when you can by one of those "ground lift" adapters at just about
any supermarket (look by the lightbulbs) for a buck and a quarter for a package of
Other Buzz'es

Buzzing might be from a grounding problem. Or crossed cables. Or
florescent lights.
Or, it might just be the nature of the beast. Ths DS_1
Get one of those 7 band DOD Eqs and roll off the top end. That'll help a
bonkrz.... tonykennedy
>>> florescent lights.
??? Really. I didnt know that they were allergic to floroscent lights. But
when I was playing bedisde my computer it was creating that noise. After I
shut it off, the noise cut back a lot. Well, it only happens when I dont
play and keep the DS1 on. I hope the noise doesnt get mixed into my
Yes, i did try the noise gate. I have to push the thresh hold upto 70 to
get rid of the problem, but it is impossible to play at that level.
I think it might be my cheap cable. I will try with the better expensive
cables I have. I think tony might be right about cross cables.
But thanks for helping :)
Q. But when I was playing bedisde my computer it was creating that noise. After I
shut it off, the noise cut back a lot.

You answered.  Video Monitors Cause Interference. Respect a little distance or use a noise gate - or even a noise gate plug-in if you're recording in your computer.
I sometimes learn new licks on the web. and
are a couple of sites. Anyway when I turn my guitar
so that the pickups face to computer / monitor mine makes
an annoying hiss. If I back away or turn it away it quits. Maybe it's
the Radiation? :o Just kidding. It's something the pickups are
picking up.
Terry Bush...
"...........Radiation? :o Just kidding"

Actually, Terry B., I think you're correct. The RF (Radio Frequency [?])
the monitor puts out is being picked up by the PUP. The wave is rather
direct and not very great, otherwise moving further away or turning away
from the monitor wouldn't help.
One could find an RF filter in say "AUDIO" magazine or any reputable Hi-Fi
source, although I'm not sure this would solve the problem.
You could always put your monitor in a cage of chicken wire........break up
the signal some......but who the heck would want to stare at a monitor
through chicken wire?.... not me.


p.s. "Terry B." not to be confused with "B. Terry." ;-))) For those who
got the two mixed up ....... well, that's for you!!
It's called EMI, or Electro- Magnetic Interference. It's a cousin of RFI,
which is Radio Frequency Interference. EMI is usually an annoying growl that
goes away as you back away from the source, turn the source off, of change
the angle of you axe relative to the source (in this case the source is the
degaussing coil in the computer monitor). RFI can also be a buzz or a growl,
or it can be that annoying Latino station that keeps playing Mexican Ooompah
music that you get coming through your guitar and amp (not intended as a
racist remark- I have nothing against anybody no matter what color they are-
I just can't stand polka music!! How'd the beer barrel polka get to Mexico,
anyhow? I never saw a Hispanic wearing lederhosen.....). The only real fix
for these sources of interference is a hit or miss combination of chokes and
expensive cables. Some people shield the pickup cavity on their guitars to
try and cut back on the effects. I bet Bill Bores would have something
useful to add here........
The reason I make the distinction is because, during all the discussion on
this thread, nobody has made the distinction between the above types of
interference, which travel through the air and are really hard to fix
reliably, and your plain old garden variety 60HZ hum which can be caused by
bad cables, ground loops, poor electrical wiring, dirty power, etc. Those
have a completely different set of fixes. The test for which is which is
pretty simple- if you can pretty much make it go away by rotating slowly in
a circle until you hit a spot where it quits (or diminishes greatly), you
probably have an EMI/RFI problem rather than a power/grounding problem.

All that said, I think Sonnet's root problem is that he's feeding the input
stage of the RP too hot a signal. Remember, the input to the RP expects to
see a wimpy little signal from the magnets in a set of guitar pickups, and
the signal from the distortion pedal is probably considerably hotter than
that. This is called an impedance mismatch. It will really aggravate the
noise coming out of the distortion pedal (which is inherent in the design of
the pedal). Try turning the output of the distortion pedal down. Someone
suggested a DOD 7 band Graphic EQ pedal between the distortion and the RP-
this is probably a good since, as I recall, the DOD unit had an overall
level input as well as seven bands of EQ. This would probably help a lot.
The DOD is a good unit- I used to have one and I'm sorry I sold it.
Hope this helps everybody-
The Axeman (##(===>>
GZS Muzik <>
 GNX Mail   (and Gnx3 Junkie site)
return to Patches & Links
gnx3 pics below

Here is a good essay Darwin wrote on the improvements in the GNX series.

The GNX is, hands-down, a much more powerful unit than the original SDISC powered units, that's for sure. They've cleaned up the sound, overall. My RP6, for the most part is a good sounding unit, however, things like the phaser/flanger produce a bit of "noise" when everything is supposed to be quiet. The RP7, I believe, had the SDISC processor and not the SDISCII, so it would do some of the same things. Even my SDISCII (in the RP12) is a bit noisy.
Overall, the RP6/7 is a more "mellow" unit than the RP12 was. The RP12 sounds "digital" if you have to pigeonhole the overall sound. The RP6/7 have a bit of "mud" to their overall output, so they are a bit better. The cab emulators aren't bad, either, for the most part, on either the SDISCI or SDISCII.
However... once you get into the GNX series of processors there's a world of difference. They have a lot of horsepower under the hood for digital effects processing and the effects are MUCH cleaner than the SDISC's of old. Four band EQ, as opposed to your current 3-band... allows you to custom-taylor the sound a lot more than before. There's also a great deal more options for Q (bandwidth) control on the GNX series which will allow you to "target" specific ranges of frequencies much more accurately w/ the band.
The effects, themselves, are more versatile. Compressor actually has settings for threshold, ratio, etc. rather than the old "single control" where all of that was done for you. Reverb, has Decay, Pre-Delay and other functions not available on the RP7 units, as well. The delay, too, is much less "noisy" and more "crisp" in sound, making the overall delays a bit nicer (I like them clean).

All in all, the processing power that you have with the GNX, in the digital section blows the RP units away, completely (including the RP2000 - although it has its good points, too).
Moving on... Amp Models, well, they're better than the RP2000 and you don't get them in the RP6/7. The cab emulators are darned good, too and you get a heck of a lot more cabs w/ the GNX2 (even the GNX1 has a lot, but fewer than the GNX2). The ability to mix/match amp models is really cool. Basically, that's starting to get where most players are, today. If you look at most setups, in the studio and on the stage, they consist of a mixture of amps to get the tone that the players want, rather than being stuck w/ a single amplifier. The GNX allows you to replicate the same types of setups. Obviously, the RP6/7 doesn't allow for that.
One of the critical "tone" derivatives, if you're playing rock, is the ability to feed an overdriven amplifier w/ a distortion pedal. Hendrix did it... most of the players, today do it, as well. The GNX1 does not allow for that. However, the GNX2 has built in emulations of most of the popular distortion pedals out there. With that, you can put the distortion pedal before the amp model... overdrive the distortion, overdrive the amp model and voila, you have more distortion that you know what to do with... I, personally, at times, use this type of thing. With my RP2000 and/or the GNX1 you'd have to purchase outboard distortions pedals to feed the thing. This allows you do that, right in the unit.
Overall, the GNX series of processors is a great buy. The things have a lot of power, etc. for the money, that's for sure. Not having to need a room full of amps/speakers is really the "alluring" part of these pedals. However, that said, if you're looking for AWESOME amp emulations this thing isn't going to give them to you. They are "processed" amps and they're not all that accurate (yeah, I owned a few vintage amps, too)... The tone controls are more like "snapshots" than actual controls. You don't get a model of the Bass/Mid/Treble/Presence knobs like you would on the real amps... rather you have to guess where the overall tonality is, on them, and then tweak the Parametric EQ to emulate what you're looking for. Unless you're a master at EQ, that can be frustrating. Plus, many times, you end up w/ the wrong EQ settings for the amp model you're working w/ and you can't copy all that well.
Amp modeling is still the best in the LINE6 series of gear. BOSS's COSM (Composite Object Sound Modeling) is the next best version, in my opinion. Both BOSS and LINE6 have done stellar jobs in creating great amp models. BOSS's GT-5 pedal sells for about the same price as the GNX, has all the same features and a ton more... Effects loop (yes and effects loop on a multi-effects processor), guitar synth for duplication of strings, bass, brass, etc... totally (and I mean totally) programmable effects order... lots more patch storage, etc. The one thing I don't like about the BOSS... actually a few things... changing patches is a horror! Manual mode... not much better... the amps that they modeled, while slightly limited (11 models I think, plus 2 acoustic guitar models), were a bit on the "dark" side... they don't have the "punch" that you'd expect to find in the amps. However, that said, they are very good, overall.
OK... so what's best... if you're looking for sheer signal processing power, quiet and pretty good emulations, the GNX series is something to seriously consider. They are ultra-quiet, powerful and have some pretty darned good presets. Amp models are "so-so" but good, as are the cabinet emulators. If you're looking for drop-dead, killer, amp models, LINE6 is the only way to go, but you give up some good things in the signal processing chain... depends on what you're really after, for the most part. For me, I use, a lot, the BOSS GT-5 w/ a POD2.0 in the effects loop. It gives me killer pre-amp sounds w/ pretty awesome effects processing power. However, it just depends on the application.
Have a good one. Hope that helps. Questions/comments? Let me know. Always glad to answer.
Well, that's about it...
For live situations, Its hard to beat the Digitech line of  Gnx processors.
 latest and greatest  GNX3              return to _Patches & Links
I feel like a Treckie with this next section. Haha

this was the first stab at Gnx3 ver.01 lousey pic but you can see the layout

  (well its ver .0 2 now)  ver .0 3 has different switch functions, see lower down
This is a different pic from the one in there brochure (its ver1)   we'll see what the final product looks like.
GET A BROCHURE on line   for the genex line!
page 10 has the original look at the gnx3.
check out page 8 it will blow you away.

PDF. specs from mf for the GNX3 (subject to change)

Here's the offical GNX3 manual

need a .pdf reader?

stomp/amp/effects/delay/play? wheres the control switch? cant have it all.
(They have since changed the pedal assignments to stompbox,amp,choris/mod,
delay/?/tap and CONTROL....YES)
ver .03 (this pic from a web site and not to clear)      
This is an awesome machine
8 tracks of digital recording!  whow wonder how it outputs?(floppy? wav?) .
well its a smart mediacard!. With some Cakewalk software.
Hey, im a Man, where's my remote? hehe...

Heres a site that has sound clips from the 8-digital tracks on board the unit

DigiTech's new GNX3 Guitar Workstation has been awarded EQ Magazine's coveted Blue Ribbon Award for 2002!
from MF

8-track digital recorder
2-track simultaneous recording
Footswitches mappable to recorder shuttle controls
JamMan2 full-featured loop recorder
Drum machine
GeNetX amp and cab modeling with 'Warp" function
Stompbox modeling with expression pedal
Guitar and mic ins
1/4" stereo and S/PDIF outs
Smart Cards---

and from

You've got an excellent point Tom. I was looking to find a new RP2K for
my drummer's kid. He couldn't wait (drummers are always in a hurry, except
to show up at rehearsal :) and got his kid the GNX1. That kid is spoiled
rotten!! Anyway, got to play with it for a couple of hours. I'm impressed
with digitech's ears. The stuff that folks didn't like about the RP2K, that
I heard about and experienced on this egroup, were fixed on the GNX1.
The unit has an on/off switch. It has a power plug like a stomp box. The
tuner is accessed by pressing and holding the first two buttons. Parameters
are adjusted by knobs. I like being able to go from red to green channel
seamlessly. The amp sims sound a touch meatier. The expression pedal has a
metal post going down inside instead of the clear plastic thing.
I'm impressed so far...
Terry B....(Bush)
whats old is new
This is the update you've been waiting for. The 1.0 firmware has been released to production. We have several production GNX3s built and many more in progress right now. We plan on shipping a small quantity by tomorrow and mass quantities on Monday. Obviously, it will take some time to get to your local dealers, so I can't say when you will see them. I would expect those in the Western states to get them by the end of next week. Thanks for waiting everyone! You'll be glad you did. And to any who have bought a competitor's product in the meantime, I highly recommend you go check out a GNX-3 before it's too late to return it. They're gonna have to pry my prototype unit out of my cold dead hands!
Josh Kapp
date: 5/9/2002

 GNX3 designteam
this is the link to the picture of the GNX3 team. (the ones who designed and took a woopin from some fanatic players who waited long and--well a long time any way.)

Ver.1.0 in pic
Pictured left to right: Jim Lambrick, Roger Mann, Paul Howard, Jim Pennock, Joe Malocha, Andrew Lovegrove, Ron Baker, Billy Clements, Josh Kapp, Mark Gerberding, John Hanson, Jeff Pace, Troy Birch
Hats off for the most excelent unit ever made. B.Terry
p.s. some if not most, of these guys, developed the older rp units

Re: GNX3 Engineer Team
I didn't want to steal the limelight. I played a very minor role with the GNX-3, so I thought it appropriate to blend into the background. Some of the other guys in the photo have some serious battle scars from the GNX-3. It took some serious engineering talent on their part to put this thing together. Frankly, I'm still amazed when I think about the unit. I can't beleive they packed everything in there for such a low price. The 8-track smart media recorder itself is probably worth the cost of the unit.
Josh Kapp
date: 5/20/2002

Shipping news?--

Hey digitech send me a free one for all this free advertisment?-- BTerry

RP2K Patches
rp-100 sites
Digital Audio Workstation
Sound Card Recording
Music copyrights   USA
Get paid  
Got a Band?
Work in Film
Sound Thinking
Solar Power Links