Tonestack simulating software

In another thread in another forum (in a galaxy far far away?), I posted some shots from a little Windows app I have called Tone Stack Calculator.  It has the ability to slot in component values for the major configurations, set the controls to where you want them, then plot the frequency response it gives.  Anyone who wants a copy can find it here:

Tone Stack Calculator Download

If that ever goes down, (it shouldn't, Duncan's Amp Pages is a well established online audio source), I can email a copy to anyone who wants it.  Just message me your email address and I'll kick it out to you.  It's a freebie so I don't think I am breaking any rules by offering that.

Like Brad Pitt says in Mr. and Mrs. Smith; the movie, right before he shoots Lucky in the bar's back room, looking at the gun that one of the card players has:  "That's cool Man!"  I love that movie. Brad is way-kewl in it.

Thanks for the link BB. I have always struggled with getting eq dialed in nicely.  I think I have some high frequency hearing loss and it has always messed with my ability to dial in bass/mids/treble.

Do you think it will help a simpleton like me figure out how to get the best out of the GM?

I don't think it will necessarily give you settings you can use direct on your amp, but it will give you an idea as to how the tone controls interact with each other if you play with it.  It has already let me see a few useful basic factors in the way they work.  We often forget of course that the traditional tonestack is a flawed piece of kit.  Twiddling the treble does not just lift and cut the treble, the other areas are affected too.  There are other configurations which give far greater isolation, the Baxandall (sometimes called the James) for example, and there are systems from hifi where the lift and cut is replaced with more of a tilt mechanism around fixed points which can themselves be varied.  Something to think about maybe.  Assuming the other two controls stay central at 12:00 :-

I can see that the bass seems to be the most independent of the three.  As well as lifting and cutting the bass, using that causes a 1-2dB change in the mid scoop and a very slight drop in it's frequency.  That's to all intents and purposes inaudible which makes it a good well defined control.

The mid control shifts the mid scoop up and down in level as we would expect again, without too much frequency shift.  It also lifts the treble end by about 3dB.  That would be audible wfor most people though not necessarily marked as unpleasant or aggressive.

The treble lifts its own region in a very flat fashion by about 13dB, though that amount is very high up in frequency.  It's about 7dB at 4kHz which is about our limit.  By rights it should sound the most effective of the three though there is limited high frequency energy in a guitar signal driving speakers designed for guitar.  It also has the strange effect of lifting the bass end 5dB or so in the opposite direction and shifting the mid scoop and dropping its level too.  Lift the treble fully and the mid and bass fall significantly.  Understanding the need to compensate for this could help get better tone settings.

With the treble full up the mid control will have its effect reduced by the fact that the mid is depressed by the treble control.  I can't remember who made the observation, (VoodooJeff maybe?), but in a thread somewhere I can remember someone recommending that mid adjustment sounds better if at the same time the treble is reduced from high settings.  This gives the mid more range and lifts the bass to match it and stop it sounding thin.

These plots need to be superimposed on the response of other parts of the system, in particular the speaker.  To make more sense of it, it would be good to combine this curve with the speaker plot with its mid hump and early fall off at both ends.  If we could add the two together we would get an idea of just how flat the overall system response is.  Then there is the question of hearing curves too....  And so it goes on ad infinitum!  Someone on a different forum used the term Analysis Paralysis!  I think of it as Trapped In thought.  We are not philosophers, (at least in this context), we are creators.  We need to see how this affects our ability to create the music we love.  It's too easy to get locked into a spiral of chasing the technical understanding of what is going on to the exclusion of ever putting the knowledge to any good use.  (And it's too easy to get locked out of it too.)

You can maybe see what I mean, that it's a tool which is useful to see the interaction between the controls and use them to compensate, rather than being able to spot certain settings which you know will sound good.  Maybe someone who has worked with this type of display for many years can do it but it's beyond me to say how an amp will actually sound from the type of graph we have here.  In the early days of digital music and picture they did comparisons of how critical the ear and eye were to digital rendering of their material.  It was found that, if we take the dynamic range of the two and split it into steps, the ear can perceive a step in sound level many times smaller than the eye can with brightness.  The ear is much more critical than the eye.  Effectively the ear needs much more digital resolution to give a lifelike rendering of a sound than the eye does.  (This was before the advent of iTech and the dumbing down of critical listening!)  At the end of the day I think the simulator graphs can point out ideas to play with to see how your ear reacts to them.  It's always best to let the ears have the final word with music.