The JC ET part 1

[Ola Andersson]

The Dr. Jim Colemans Equalbeating ET! 

Part one: The aural inharmonity test

About one or two years ago I got this temprement  from Dr. Jim Coleman 

I can't tune without it and I think it's great but I never heard it mentioned anywhere else.
When Dr. Jim Coleman mentioned his new Aural tuning video I was sure that a part of it was about this temprement. I therefore asked him if it was OK to share it. We all know that Jim is a sharing person and ofcourse he said yes. If there are anybody thinking about taking the RPT test why not buy Jim Colemans videos? He have repairing, regulating and tuning videos. They are great and cheap!             Jim Coleman, Sr. <pianotoo@imap2.asu.edu>

Jim Coleman calls this a Sanderson/.... temprement but I call it the Coleman temprement because I think it is his own. Exactly now I cant find my copy but I thought of mention the First genius part first.  I might have changed it some so I hope Jim jumps in to correct me.

Ok let's go

1, Tune A4 to fork
2, Tune A3 as a 4:2 octave from A4
3, Tune A2 as a 6:3 octave from A3

This first part is a normal Sanderson/... start I guess. 

Now to the first genius part
This is an aural inharmonity test for how fast the thirds really are. The point is to tune the A3-C#4 with help of the F's at same speed or with other word with the F's too flat. We will end up with a A3-C#4 third that we not are going to change. As I been told I found that pianos have different speeds on the thirds. I mean A3-C#4 can vary(sp) on different pianos. 

Here's Colemans way to find out.

4, Tune C#4 to A3 "9bps"
5, Tune F3 to A3 "9bps"!!! or same speed
6, Tune F4 to F3 as a 4:2 octave
Check if you get the same beat on C#4-F4 as you get on the others "9bps".
If not retune so you end up with the thirds at the same speed 
Ofcourse don't touch the A3! (Don't ask how I know:-)

Usually on my consols the thirds is slower but the point is to get them to the the same speed
F3-A3 "9bps"!  A3-C#4 "9bps"  C#4-F4 "9bps"! 

Yes the F's are to flat but the point with this is to find the natural beat of the A3-C#4 third
It's like an aural inharmonity test. I think I usually ends up with all thirds closer to 8bps! on my pianos.

So when you find the right speed don't change the C#4. 

7, Now tune the C#3 as a 4:2(+) octave from C#4
The A2-C#3 third will now have the same speed as C#3-F3 if you are right, (a nice check)

Now tune the the F's so you get the real contigues thirds.
F3-A3 "7bps" A3-C#4 "9bps" C#4-F4 "11bps" 
We will now have contigues thrirds from A2-A4

It is also possible to tune 
F3-A3 "8bps" A3-C#4 "9bps" C#4-F4 "10bps"
Like I sometimes get the the F3-A3 same speed as A3-C#4 but the C#4-F4 is slightly to fast. Then I make the C#4 slightly sharper so I get a progression of the thirds.


                      "I DO IT MY WAY"

Well ofcourse I have my own way of doing this because I think it's kind of hard to hear the C#4-F4 third om my consols

First I tune the three A's. A4, A3 and A2

4, Then I tune the the C#4 to A3 "9bps" or a bit slower. 
I often use a metronome at 131bpm thinking 16notes.

5, Then I tune the C#3 from C#4
6, Then I tune F3. C#3-F3 same speed as A2-C#3 (about 4.5bps)
The F3-A3 should now have the same speed as A3-C#4 (9bps) if not then I retune 

7, If I'm happy with it, then I tune F4 as 4:2 octave from F3
C#4-F4 should now have the same speed as F3-A3 and A3-C#4.
If not then I retune:-(

If I'm happy with it, then I tune the F's as contigues thirds.

This might sounds complicated but with training it goes fast and when you find the C# you don't have to change it and you know where to put the F's and then the rest is easy. This gives 2 notes (A and C#) that you can build the rest of the temprement on. There are  more genius parts of this temprement by Dr. Jim Coleman but I write about that later.

It's also possible to tune a Vallotti from the A3-C#4 third
or a Marpurg III after tuning the contigues thirds. 
Bill Bremmer has a good explaination of the Marpurg in the archives

Yours 

Ola Andersson
Bergen, Norway