MIDI Expression with Kawai F-10H

[hz]

Hello Robert,

I recently came across your MIDI Expression pedal interfaces. Great work!

I am considering one to use with a Kawai F-10H continuous sustain pedal. So, I would like to know if your interface and this pedal are compatible and its positions would neatly and usably translate to 0-127 CC MIDI values.

I have done some research by measuring its behavior and taking a look inside. Here is what I know thus far:
- It uses a TRS jack with 'straight polarity' as you call it in your manual;
- So it takes an input voltage with ground on the Sleeve and the + voltage on the Ring. In my test situation I applied approx. 3,25 volts to it;
- With the pedal in the full up position, the output voltage on the S+T as well as on T+R is about half the input voltage on S+R;
- Depressing the pedal gradually to its full down position gradually changes the output voltage: T+R decreases to almost zero, and S+T increases to almost the input voltage.

Now what is different in this pedal from several others (such as the Roland DP-10 in its continuous mode), is that it uses a (presumably optical) tiny proximity sensor and a simple few components (including one tiny transistor) instead of a potentiometer to do this voltage division. The half-voltage on the output in the full up position is also somewhat different, I guess (as opposed to either almost-+ or almost-ground).

So, what do you already know or can you sensibly say about the compatibility of your MIDI Expression interface with the Kawai F-10H?

Out of curiosity, your name 'Robert Jonker' could typically be Dutch, however, I get the idea that you are not residing in The Netherlands. Could you shine some light on this? Also, and this is a word of a little concern: nowhere on your website I have been able to find a company address, actual contact details and so on. It feels a little obscure to me that this forum appears to be the only means of contact. This is less than customary for a business and, if I am not mistaken, would even be illegal to omit in my country (The Netherlands).

Anyhow, thanks in advance for your answers, and keep up the good work,

HZ

[Rob]

Thanks for the detailed description of the Kawai F-10H. It should work fine. The pedal sensing feature might have some trouble with it, but you can use the Control Application to set it as an Expression pedal, set the 'Polarity' to straight, and then calibrate and all should be good.

My name is Robert Jonkman. I'm a Canadian with 100% Dutch blood, living in Taiwan. I'll make a section on the website called 'About Audiofront' that will give more information. I operate as a sole proprietor out of my home, so including my personal home address on the website seems a bit odd. I do provide my address and contact information on invoices, however.

Regards,
Rob

[hz]

Hello Rob,

Thank you for your swift answers -- and apologies for getting your surname wrong in my original post!

Interesting to read that you are a Canadian with Dutch origins, given that I am Dutch with a desire to become Canadian at some point in the future. As for not including your personal address online -- as a small entrepreneur myself I totally get that. And yes, an 'about' section would be a worthwhile addition. It might eliminate possible preliminary concerns that people may have, and add a little personal interest and something to relate to for new visitors-becoming-customers.

I will quite probably have a go at your MIDI Expression interface and see how that will improve my 'use case' with the Kawai F-10H pedal, as described earlier.

Best regards!

HZ