www.megadrum.info

Hi,

I have the task to build a midi harp.
so, each string of the 36 strings (nylon, Carbon, copper-wound nylon)
should have a signal.

Could be installed like the little metal-piece here:

[img]
http://www.artefakt-musik.de/bscoh2.jpg
[/img]


Now the question is, what kind of Piezo could I use?
(the roundlings for the drums are too big, and probably take too much of
the vibrations of the other strings).

Has anybody experience with stringed instruments?
and likes to share it?

Would the rest of the hardware work, what do you think?

Best wishes and thanks, Klaus

I do midi guitars. I use roland's divided inductive pickup that uses steel strings. http://www.rolandus.com/products/productdetails.php?ProductId=651
It has a pickup coil for each string. That is how they deal with x-talk(vibration from other strings). I don't think that will help with nylon/carbon/copper wound strings tho . Plus you would need 6 pickups and 6 midi interfaces for 36 strings. How much flexibility do you have behind the sound board inside the body? Your web site has very nice harp pictures on it.

thanks for your answer,
the advantage of megadrum seemed to be, that this hardware can cope
with 56 signals, so i thought,
maybe it is enough to find / to experiment on the transducers
(how much crosstalk I would like to have - in fact is is
an important part of the harp sound, the co-resonating strings).

So, I wondered, why not find piezos,
like the ones used in Godin-Nylon guitars
(they do not answer my questions...)
and combine them with the Megadrum Hardware?

do I think wrong in anyway?

best wishes, Klaus

artefakt wrote:the advantage of megadrum seemed to be, that this hardware can cope
with 56 signals

I agree since you have 36 strings.

artefakt wrote:So, I wondered, why not find piezos,
like the ones used in Godin-Nylon guitars

When I read your post, this was the first thing that came to mind. Especially after I saw pictures of your harps. A nylon guitar pickup approach would be the one I would choose.

artefakt wrote:(how much crosstalk I would like to have - in fact is is
an important part of the harp sound, the co-resonating strings).

When I heard the audio clips on your web site, I thought the same thing. My experience with midi stringed instruments is that x-talk tolerance varies from sample to sample and the musician's playing style. The result is that each different sample is a unique instrument that requires you to learn how to play it in order to get the best sound. This gives x-talk an empirical quality that is difficult to predict. In my opinion, the best way to find out is to put it together and see what happens.

artefakt wrote:do I think wrong in anyway?

No, if I had a harp, I would make it midi. Everyone should have at least one stringed midi instrument!
Good luck. I look forward to seeing your progress.

I would use a very small piezo. 15mm or so. It should still pick it up easily and yet cut down on cross talk sensitivity. Keep in mind that 36 strings means 36 piezos and 37 wires if you tie the grounds together. It will be interesting to see how you hide all of that plus the electronics!

jman 31 wrote:I would use a very small piezo. 15mm or so.

I agree with jman 31. Find smallest piezos.

jman 31 wrote:It will be interesting to see how you hide all of that plus the electronics!

Ndeed. A router would do nicely. I put the electronics inside the instrument. That gives a clean, professional look. This picture gives me lots of ideas.http://www.artefakt-musik.de/bausatz.htm

Hey thanks for the contributions.

To hide all the cables should be no problem.

Hopefully I can get Midi Pickups from another harpbuilder.

He has a solution, that the notes C D E F G etc....
are programmed already in the boards software.

With Megadrum this is done by the software, right?
So I Need:

- Pickups
- Preamps??
- Megadrum Module
- midi cable
- Laptop with Megadrum-software
- and then - where is the sound produced? So I need an external soundcard, that has Midi, right?


As I understand the Megadrum-Solution
I only have pickup 1,2,3,... running into the broad-cable?
then into the mainboard.

So I´d like to have all this installed inside the harp, also the LCD,
as the harp is already a box

A stupid newbie Question:
Why does the 56-module haveonly 29 input jacks on the backside?

Thanks a lot,
best wishes, Klaus

artefakt wrote:- Pickups
- Preamps??
- Megadrum Module
- midi cable

MIDI cables are not required. You can connect MegaDrum over USB.

- Laptop with Megadrum-software
- and then - where is the sound produced? So I need an external soundcard, that has Midi, right?

You need a low latency sound card (google for "ASIO") and any midi aware sound synthesizer software.

A stupid newbie Question:
Why does the 56-module haveonly 29 input jacks on the backside?

27 of them are stereo with two inputs in each.

On the way to a solution here´s two more Questions:

1) harp-specific is, that you do not have the black keys like on the piano.
these semitone steps are made by Pedals or levers.

Lets say I have a switch on the Pedal, so the note C should be played as c sharp.
how do I feed this alternation in the Board,

Is this possible, or does it need programming?

2) If - for another type of harp - I would need 60 signals / strings,
can I use the smaller kit and the bigger kit together? Or is there an other solution?

Thanks so much for your answers so far.

Best wishes, Klaus

artefakt wrote:On the way to a solution here´s two more Questions:

1) harp-specific is, that you do not have the black keys like on the piano.
these semitone steps are made by Pedals or levers.

Lets say I have a switch on the Pedal, so the note C should be played as c sharp.
how do I feed this alternation in the Board,

Is this possible, or does it need programming?

You will have to do it in software which modifies all notes played based on MIDI CC data recevied from the HiHad pedal position. I don't know if any software can or cannot do it.

2) If - for another type of harp - I would need 60 signals / strings,
can I use the smaller kit and the bigger kit together? Or is there an other solution?

You can chain MegaDrum over standard MIDI or connect several MegaDrum modules to a PC over USB.