MegaDrum Velocity Sensitivity

[alexmcintosh]

Dmitri;
For the answer I'm using my 14" Hi Hat (DIY A2E Cymbal, Dampened with PVC from Macmaster-Carr, 27mm Piezo attached with E6000 glue) The Hi Hat had a HighLevel of 604.
It's set it to a Standard Linear slope and below are my results:

1. When you set HighLevel to 604 you easily get max velocities with hard hits, right?
Reply: Yes, I get 127, but with a Medium hit.
2. When you set HighLevel to 605, what max velocities do you get with hard hits?
Reply: I can only achieve 126, with a medium or very hard velocity
3. When you set HighLevel to 606, what max velocities do you get with hard hits?
Reply: I can only achieve 126, with a medium or very hard velocity
Reply: (607) 126, with a medium or very hard velocity
Reply: (608) 126, with a medium or very hard velocity
Reply: (609) 125, with a medium or very hard velocity
Reply: (610) 125, with a medium or very hard velocity
Reply: (611) 125, with a medium or very hard velocity
...
... When you set HighLevel to 610, what max velocities do you get with hard hits?
Reply (612) 125, with a medium or very hard velocity

(Note: I did try to change to a shorter 3.5mm cable, and it did not seem to help)
Thank you for the reply, and any insight you may have to make this implementation better is greatly appreciated.
Alex.

[dmitri]

Make sure that MinScan is set to at least 50.

With Curve set to Linear and HighLevel set to 605, post the following screenshots from MIDI Log/ Visual MIDI with hits between central piezo and the rim:

1. When you do free bouncing stick.
2. When you do a dozen of light hits.
3. When you do a dozen of semi medium (between light and medium) hits.
4. When you do a dozen of medium hits.
5. When you do a dozen of semi hard (between medium and hard) hits.
6. When you do a dozen of hard hits.
7. When you do a single "press roll".

Post a screenshot of settings of the pad.

I have a suspicion that medium to hard hits produce electrical signals of equal level due to either bad piezo or mechanical construction of the pad.

[alexmcintosh]

Dmitri;
I got it to work very well when I added a 33k Ohm Resistor (in series).

Also, I noticed that none of the inputs can read a signal above 604. So, it's not the cymbals that has this HighLevel limitation, but the cymbal design brings out the worst in the HighLevel, 604 limitation.
I attached the screen shots you asked for; but omitted anything harder than the Medium hits, as this would be redundant.

Any thoughts are greatly welcome.
Thanks.. Alex

[alexmcintosh]

Dmitri;
here's the other picture..

[dmitri]

It seems to me there is something wrong, that is hits from medium to hard produce the same signal level.
With Curve set to Linear and HighLevel set to 1023, post the following screenshots from MIDI Log/ Visual MIDI with hits between central piezo and the rim:

1. When you do free bouncing stick.
2. When you do a dozen of medium hits.
3. When you do a dozen of hard hits.
4. When you do a single "press roll".

[alexmcintosh]

Dmitri;
I'll post the screen shots you mentioned. But, wanted to clarify that the screen shots I took were without any (series) resistor,. And, that if/when I add a 33k Ohm resistor in series, it works really great. (After reading my description, this seemed unclear.. just in case this is relevant to your concern)
Also, I wanted to point out that my HiHatE is a piezo mounted on the bell. Just in case this is relevant to the hits between the piezo & rim you wanted.

Thanks..Alex

[alexmcintosh]

Dmitri;
Attached are the requested screen shots.
HighLevel = 1023 (HiHatB = Note =7, Curve = Linear)
It Peaks out at Midi Value = 74.
Thanks.. Alex

[dmitri]

I see again that there is no difference between hard an medium hits. At the moment I can see only one reason - signal levels from piezo are the same, i.e. they's already maxed out with medium hits and hitting harder doesn't make signals stronger.

[alexmcintosh]

Dmitri;
I just tried attaching the Piezo's I'm using directly to the ribbon cable and testing it. They max out easily at MidiValue=74 (HighLevel=1023) (just as the previous screen shots show for the Hi-Hat).
I'm using 2 different Piezo's in my design:
1.) 27mm Diameter, 20 V p-p (DigiKey Part#: 102-1127-ND)
http://www.digikey.com/product-search/e ... 02-1127-ND
2.) 35mm Diameter, 30V p-p (DigiKey Part#: 102-1128-ND)
http://www.digikey.com/product-search/e ... 02-1128-ND

They're outputs are 20V & 30V, Peak to Peak, but I'm getting the same HighLevel.
What do you think?

Sincerely; (and very gratefully) .. Alex.

[dmitri]

I don't think your piezos are at fault. Piezos naturally max out at some level of applied force and no matter how harder you hit them they won't produce higher voltage. In your case, it appears to me, you have such a design that transmits more force from your hits to piezos than your piezos can handle. What you need is to dampen transmitted force, e.g. putting damping stuff between a piezo and a surface it's attached to, or, in case of using a mesh/cone design pad, use a softer material for a cone or lessen pressure from a cone to mesh.