Everything is running on batteries here, outside on my back porch. A Yamaha PSR-310 ($149) plays an arpeggio throughout, sending MIDI notes of a C-Major chord, which you hear at the beginning going through the box in bypass mode (no retuning). That chord then gets retuned in 15 different ways, and I noodle around (not much keyboard skill shown here!) over the arpeggio in each tuning.
The H-Pi "factory" (a.k.a. "my home") normally gives the appearance of multiple natural disasters having recently occurred, but early this morning was no mere verisimilitude. An actual earthquake shook the place for about an entire minute. This weird right-angle crack was noticed on the south wall many hours later (it continues for several feet in both directions from the detail shown). Luckily, this was the only calling card left by the 5.2 magnitude quake whose epicenter was about 50 miles away. An interesting, if a bit over the top punctuation for the last day of pre-order discounts on TPX6/8/s keyboards.
If you are a microtonal composer, theorist, enthusiast, or just an on-the-go tuning geek (you know who you are), then you need the TI-34 II. This handy little device is, in a word: ‘the bomb’. Here’s why:
Need I say more? Well, maybe a bit…
So you want to calculate all kinds of ratios and get reduced answers? Piece of cake. You want cent values from ratios? You want to measure intervals in the special unit of your own geeky choice? You want your results accurate to 5 decimal places? You want to round your results to integers? It’s all right here, my friend, at the touch of a button.
For example, the following formula gives you the cent value for whatever you throw at it, rounded to three decimal palaces. Program this formula into OP1:
= round(1200×(log(Ans)÷log(2)),3)
Bam! It’s ready to work its magic. Type in whatever you want to see in cents. For example, type 5/4 and press enter. The screen displays 5/4. Press OP1 (that you just programmed). The display will read 386.314, the correct cents value. Now that’s cool.
You want some other unit? Of course you can change the formula every time you want a different unit, but changing the formula once to use a variable instead of 1200 all the time is a better idea. Use this for OP1:
= round( A ×(log(Ans)÷log(2)),3)
Then for cents you would type in 1200 and press store and enter to save it in memory location A. Obviously, you just change the value of A to get some other unit. For example, type 53 and store it in memory location A for 53ET. Now let’s map 11/8 to 53ET. Type 11/8 and press enter and then OP1. Bingo, you get the answer: 24.350
If you wanted that answer rounded to the nearest step instead of three decimal places, obviously you just change the last number in the formula for OP1 from a 3 to a 0:
= round( A ×(log(Ans)÷log(2)),0)
Then your answer would just be 24. Since there are two OP buttons, you can of course set up two formulas, one rounded to integers, one rounded to some number of figures, and you can use different variables in them, so you see it’s all a breeze.
Another obvious use for the two functions is to program one of them for the ET of your choice, and the other to get cent values from the answer obtained from the first function; that is, the rounded step in the ET of your choice. For example, you got the 24th step of 53ET as your answer to mapping 11/8 in 53ET. So what’s the cent value? Of course you can waste all day and type in 2^(24/53) and use the cent formuala above on OP2, but who has time for that? Instead, you can program B to 1200 and then program OP2 to this:
= round( B ×(log(2^((Ans)/ A ))÷log(2)),3)
You see that this will give you the cent value to three decimal places. So you can check out any degree of your ET stored in A by entering whatever scale degree and pressing OP2. How cool is that?
There are all kinds of ways to tweak these formulas and make others to do cool stuff with ratios and cents and whatever units you want. I’ve got plenty of my own formulas for working in 205ET that become pretty involved for doing things in MegaScore notation, but I know by now you are itching to make your way straight to Target and buy one of these little miracles, so I will detain you no longer.
This is a little sketch of a tune I came up with this morning. The sound used is from the internal synth and is called ‘PluckySynth’ with a modified envelope and EQ. Audio LINE OUT from the keyboard is mixed with external audio, along with a drum track made with the Ultrabeat synthesizer on Logic Express. This is a simple tune, which I think might sound a bit boring without the tuning control. The melodic line sings “Goodbye Cold Winter” or “Goodbye to the Winter”. Several sizes of minor thirds are used. There are a few edits and some little mistakes I couldn’t remove, but there’s only so much time in a day. I hope you find it interesting.