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Dear technicians

At the moment I am learning to tune Alfredo Capruso's C.HA.S. aurally with his preparatory sheet and with his personal help.
Here are two videos, the first one is the temperament section from a3-a4, the second the expansion down to d#3 and up to e5. These videos are not my first trial btw.
If there is someone who is tuning it too or interested in, I was happy to read some comments.

https://youtu.be/5RBskJgZFnw (temperament)

https://youtu.be/IGBrqjT0jOg (expansion)


Best wishes to all!!

Toni

I like the emphasis on the use of consecutive and progressive 4ths and 5ths as checks during the temperament building. So important to get these right before expansion.

Chris, I am a 4th and 5th tuner. Have you ever calculated the accuracy required to have "consecutive and progressive 4ths and 5ths" ? It's an eye opener!

No. I only do the best I can. More recently I have been trying 4th and 5th progression and that is what caught my attention with the video. About the best I can get is a vague progression through the temperament region with 4ths. I am more concerned though with similar quality of tempered sound with consecutive 4th and 5ths as a priority over perfect progressive RBIs. If I am satisfied with even quality SBIs then RBIs look after themselves and used as a kind of last check.

I accidentally ran across this nice video of a piano tuned to CHAS today. Great sound, despite the children playing in the background:

https://www.youtube.com/watch?v=A4L8UVTrWLc

How does this this "C.H.A.S." tuning differ from any other competent tuning? Reminds me of homeopathy.

Kees

Quote:
"The new Circular Harmonic System - c.ha.s.®, with its equation, tempers and develops a coherent, precise, tensorial and synchronic Form, which is self-regulating and self-balancing, and where each sound has its own unique value; the System uses tensorial constants to proportion the octaves and all intervals.

Thus, where Equal Temperament restrains the octave in a double arithmetic relationship, the c.ha.s.® System expands the octave and draws the tensorial curves of every interval."
Unquote:

This sounds very impressive but incomprehensibly uses inappropriate terms in an attempt to create an illusion of superiority.
When we get to the bit about "double arithmetic relationship" there seems to be an assumption that stretched octaves never before existed, and that Alfredo discovered the secret key to perfect harmonic balance.

Did Cook "discover" Australia?

It is a marketing and self promotional ploy, and the tuning methods are no different to normal established techniques given the variance that exists.

Alfredo feels that the expanded octave would be good for harmonic instruments, such as the organ as well.

To me, that would be removing the one non beating interval on a 12TET organ. Thank Ipthar for Werkemeister III.

There are several threads on this site arguing about CHAS. I'm not qualified to say who is correct. I do love the results of Alfredo's approach, however. Regardless of all else, the sound is beautiful.

Of course it can sound beautiful, as can any well executed aural method based on sound harmonic principles. But there will not be any transcending superiority due to a special and unique method.

I have listened to the various utube demonstrations of c ha s and I find that the spread of the unisons successfully disguises any and all subtleties of stretch that typify the 'designer' tunings.

Toni,

What made you decide to change to C.HA.S ?

It looks to me as being a much more involved (intensive?) tuning procedure

Ian

+1

I other words, the unisons are too bad to recognize any type of octave or other intervals? And in the video Jake found?
That interests me really.

Why interpret what I said in terms of good and bad?? I make no such distinction or judgement, I merely compared spread (stretch) of the unisons with stretch (spread) of the octaves.
Read again exactly what I very carefullly wrote and then ask your next question.

I'll give you a clue;

When the spread of the unison is greater than the stretch of the octave,
What then??

Afterthought; could it be the high degree of unison spread that is making the tunings attractive?

Alfredo suggests an octave stretch of 2.0005:1. This results in a 0.43 cent stretch, which is well below the stretch I require on A3/A4 (~2.5 cents) to accomodate for iH on my BB. The variation in unisons can easily be 0.43 cents and barely heard as a slow roll over 9 seconds at 440Hz.

iH overwhelms C.HA.S.

For me as a German speaker it sounded like a fast written criticism. But I didn't make a statement if something is bad or good, I asked a question. Maybe it would be easier for me if you try to describe again what you mean. I like to ask you a further question:

What is "spread of the unison " for you?

I can't answer your last question because I don't understand what you mean by "spread of the unison".

I am not the one how is not able to accept criticism, otherwise I was a silly boy to put videos on YouTube.

And if I answered too thoughtless, I apologize.

Hi Jan

I listened to the sound examples on chas.it and they sound very beautiful, especially Schumann 's Arabesque.
And there were curiosity reasons. I like to expand my knowledge, as I did with UT's. And I wanted to go back to aural tuning. Since I use it, nearly all pianos, even the smallest, sounds really good and "in tune" for me.

The way back from ETD to aurally tuning is not so easy, but using an ETD refined my hammer technique because they are very sensitive, and today I am able to tune aurally better than before using the machine. But there is still some more work to do, and having different possibilities to tune is very important for me. BTW aurally tuning is much more fun. And the results are surprisingly.

We define Equal Temperament as equal width intervals. But those widths are measured at the first partial of each note.

We tune, not by listening to the first partial of the lower note, but by listening to the 2nd up to the 8th partial (or higher) if necessary. This accounts for the inharmonicity of the strings. The resulting ET will not have equal width intervals because the iH is continually changing from note to note.

Whether or not you tune using Alfredo's method, or Bill's 'ET via Marpung' or Donald's 'ET for Dummies', the result will not be ET, but, depending on your skill and the instrument, a nice sounding piano.

Speak for yourself!