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Hi Ryan,

Def a brave thing to do. Since I am not a pro tuner, and use only an ETD to tune, I am not up on the nomenclature you mention: 4:2 octave in the middle range tapering to perfect 12ths into the 5th octave and narrowing to pure 2:1 in the very top half octave. I try to achieve a 6:3 tuning in the bass as soon as the piano will allow tapering to a slightly wide 6:3 in the lowest half octave.

I am not sure what Entropy is putting out...it was mentioned earlier in this thread, that it was a form of ET...perhaps Prout can talk about that.

The basic aim is to find a tuning that is as consonant as possible when all the keys are played at once!

Hi Ryan,

Ian is correct.

Basically, Entropy Tuner records and analyses the actual partial structure of all the keys. It then attempts to align all the partials when sounded simultaneously.

This is, of course, not possible, so Entropy Tuner attempts to find the closest alignment. The result is not 12TET, but, of course, on a piano, 12TET is not possible, due to inharmonicity. It is similar, however, to a normal aural tuning attempt of 12TET.

Mathematically, there are many possible local minimum entropies for an idealized 88 string instrument with no inharmonicity - for example, all 88 notes tuned to the same frequency, or all randomly tuned to an integer harmonic of some random (say A4=440Hz) fundamental.

Each calculation from the recorded data set produces a slightly different tuning due to the 'Monte Carlo' style of the algorithm.

Hope this helps explain it a bit.

Edit: I should correct a statement above. 12TET is possible on a piano, based solely on first partial interval widths. It would sound like S**t!

Recorded tuning using Entropy/Laptop/G-Trac mic...showing what Entropy can do with a simple tune.

Original high resolution .wav file: https://app.box.com/s/30tsqq2oxzcab2qg4jbhkc9cqyp8eseg

"Passapied" by Leo Delibes

The Entropy tunings sound very nice. Thanks for the recordings.

I would be interested in hearing some chromatic thrids, 10ths, and 17ths, to get a sense of how much stretch it thinks is optimal.

You're welcome prout. EPT does produce a very nice sounding tuning.

I've enjoyed exploring Entropy, as I have for other platforms, EBVT III, RCT, Stopper, Verituner, and Tunelab. '

Ryan, I won't be able to do that for awhile, as I am busy working, however, here is a selection that was recorded right after a fresh EPT tuning using my laptop/G-Track mic.

"A Time For Love" John Arpin https://vimeo.com/139053337

Corresponding original .wav file: https://app.box.com/s/fia92z9r10b6qixpj7gw9ujzn3gze5yq

Dear All,

after a long search we finally discovered the reason for the discrepancy between strobe and other indicators in the bass. The difficulty was that this discrepancy appears only on the bass bridge but there is nothing in this part of the software that distinguishes between bass and treble bridge.

The solution is the following: In the EPT we determine the fundamental frequency (the one which is shown numerically) by a two-parameter fit of the usual inharmonicity formula f_n = n f1 * sqrt((1+B n^2)/(1+B)) for the two parameters f1 and B. We did this in order to avoid problems with bass strings where the fundamental is almost missing. The formula works perfectly for pure cylindrical steel strings (and it should because it has been derived for this case) but surprisingly it seems to fail for the copper-wrapped bass strings: In the upper partials the fit is still perfect, but f1 and and also f2 do not mitch with the fit, they are systematically below. On top of that one has a kind of random discrepancy to both sides coming from the finite time window, as correctly pointed out by prout.

In the strobe we erroneously took the fit value instead of the actual f1 as a frequency reference. This can be fixed easily in one line only. Since I am still on a conference in Korea we plan to publish an update next week when I am back home. However, the question why copper-wrapped strings behave differently remains an open question for me.

Three users have also reported corrupted sound produced by the synthesizer. We could not reproduce this behaviour but we have identified a possible bug in the code which will be corrected as well.

Thank you for having identified the strobe deviation. You are looking into details and this is extremely valuable for the development of the software.

Best wishes to all of you
Haye

Partials walk in the bass as they wish) Was the theme:
http://www.pianoworld.com/forum/ubbthreads.php/topics/2288341/Re:_Partial_analysis.html
http://persianney.com/misc/proutA0-A2.jpg

Hello Haye,

Thanks for the update.

I am going to tune a friends Yamaha C5 next week, and look forward to using the improved strobe display. He is a good pianist, so I hope to record an Ipad vid of the tuning.

Going through my first tunings with EPT, I came across this Ampico piano roll. There are some good sounds here, and at the end, some good octaves in the treble.

Ampico Classical Piano Roll, EPT, laptop/G-Track mic...sorry, don't know the titles. Original .wav file direct from the Tascam DR-60..... no processing etc.
https://app.box.com/s/abbsduisuu9zds8sa4uuu1sdjauy9oo4

Interesting, in the first piece, one section sounds like the music from that animated Christmas Snowman movie.

Here is another Jazz piece, this was recorded much later than the above Ampico roll, and right after the jazz piece "Who Can I Turn To" above... center string tuning.....this man is all over the keyboard yet again. Not perfect unisons, never the less one can hear what EPT does with jazz.

"The Man I Love" Gershwin on the LX



Original .wav file, direct from the Tascam DR-60, no processing etc.
https://app.box.com/s/rsr8msj31wmuuxs3bysjhtk3w9tkvu3v

This recording was made fairly early on when I first started using EPT, pretty much right after I tuned the piano. No video for this.

It will be interesting to hear the differences with the new strobe display, although it will sound different in any case, as I will be using a new computation, than the one used for this piece.

EPT, laptop/G-track mic

"La Vie En Rose" on the LX

https://app.box.com/s/vrpu4e4g7deldhp2yv7sk4r448z28lvo

Here is a gem of a piece that I missed posting. Tuned with Entropy.

This was transcribed from a piano roll, and played on the LX.

https://app.box.com/s/qqtk4the1dmbjsp67psy6shkysq1g3hx

It looks like Entropy has just had an update. They probably fixed the strobe. I am going to be tuning a friends Yamaha C5 next week for sure, and look forward to trying it out on my laptop.

V 1.1.4. - Just checked "restore recorded frequencies" mode. Everything works perfectly. One of these days I will try to live instruments. Thanks to developers!)
For greater accuracy, I soldered an external microphone (Panasonic wm-61) that plugs into the headphone jack android.

I use Windows 7 Professional and am continually reminded by Microsoft about the free upgrade to version 10 on both my usual laptops.

I seem to remember someone saying this system would not work with Windows 10, however I wonder if anyone else has had any success with it on that platform?

It seems to work fine on my Windows 10 laptop.

I have Win 7, and am not going to upgrade to !0...as long as I can hold out it keeps asking me to upgrade...grrr. When upgrading in the past, some programs did not work, so will leave well enough alone.

Will be tuning my friends Yamaha C5 on Monday...hopefully I can persuade him to play something after. Looking forward to trying the strobe display.

It was I who first wrote here that EPT didn't work with Windows 10. But as I wrote later, it was because I was on the N version of Windows without Windows Media Player and other software pre-installed. It turns out that EPT depends on this, so installing the media feature pack for Windows 10 N solved the problem. Now EPT works fine. Also, Windows 10 is great, better than Windows 7 and 8.

Windows 10 is a much more intrusive, automated, and privacy compromising OS than earlier versions. That being said, I have it on two of my nine computers and it works fine once you install a few extra goodies it left out (no midi support for example). Windows 10 is much more robust, unlike Windows 7 (which I liked). I have yet to have the computer lock up or get a blue screen.