Midi tempering utilities updated

2002-02-11 05:00 am

A little off-topic, since this only indirectly has anything to do with NWC -- but might be of interest to those wishing to use or experiment with alternate tunings.

"Harmonic Analyser" and its related programs "MidiTemper" and "PianoTuner" have been extensively updated. The current version is V2.3b, and is available at Fred's Freeware midi utilities. A walkthrough is available for first-time users, or to get a feel for the new features.

Hope it's of use to some.
Fred

Re: Midi tempering utilities updated

Reply #1 – 2002-02-12 05:00 am

Sure it is. What does Ertugrul think of it, for 17/33 System??
BTW, what do you call (also in Ertruðul's doc on 17/33) "cent"?? it seemed to me that it was Hz value; (and because E(3)=330Hz, and A(3)=440Hz; but on Harmonic Analyser, it seems to be a delta value.
Back to NWC, so it won't be off topic after all

: How can it be used for MPCs? Does '%' value have to be multiplied by 4096 , or do we have to divide it by 2^-12 first, then multiply by 2048?

Re: Midi tempering utilities updated

Reply #2 – 2002-02-12 05:00 am

Hi Dominique,

Ertugrul has in fact been a major contributor to this project, and almost single-handedly convinced me to tackle the current update. He's been extremely helpful as a beta tester, and has probably used this program more than even I have. I notice he credits HA, so suspect that he must have found it useful in developing "his" scale.

The difficulty with any scale with more than 12 notes per octave is that midi only define 12 notes. So for such scales you have to edit down un-needed enharmonics (the tempering sub-programs make this easy) and/or fix up any additional enharmonics by hand later.

A 'cent' is 1/100 of a semitone, specifically a 12-tET semitone. In earlier versions of the software I gave the option of a "relative" cent (i.e. 1/100 of an equal-tempered n-tone semitone) but since the 12-tET 'cent' is almost universally accepted, such a contrivance would only serve to confuse.

The "percent" and "cents" value shown near the left-centre of the screen is only a deviation from the nearest harmonic (just a "point of interest", as it were). This will only be zero in completely "harmonic" temperaments. (I should note that almost all good-sounding temperaments are *not* harmonic on all notes! -- including 12-tET!) The actual pitch bend required to accomplish the desired result is given in the last three columns, in NWC format (that's the number you set the pitch bend slider to), zero-based (that's the number that actually appears as a 14-bit signed integer in the midi file), and in cents (1/100s of a semitone deviation).

All the nasty math (exponents, logs, octave division and such) are done in the program so you don't have to worry about it. About the only math you need to ever do externally is if your tone-centre is beyond midi's 2 semitone (either way) pitch-bend range, and you have to compensate by transposing. And even that is just a simple multiplication or division to find the new "effective" tone centre. (The docs explain all...)

HTH

Fred