www.megadrum.info

Hi fellow Megadrumers!

I am confident to get this thing running awesome…
but I have something that looks like a wired issue to me.


Basically:
I need to turn the threshold value of for the Rim Piezo way higher (up to 35) to avoid false fast ghost notes triggering.
On the head I can leave Threshold at 4 without any problems.

I discovered that I need to turn the threshold way to high up to avoid false triggering (up to 50 and more).
I then decided to open the box, check all the connections, resolder some, put some insulation material in between and close the box.

I have mounted 4 Jack Connectors on a small PCB Board that i had left over from a microdrum project.
I soldered the corresponding wires to the underside of these 4 boards in total and separated /insulated them with a sheet of paper.
The Box is quite dense packed. I use DIY build mesh heads, rim trigger is mounted on the rim with a piece of foamy scotch tape.

Later on…
I discovered that my issue (high threshold) was nearly completely gone as soon as I unplugged the power cord from my MacBook Pro!

This was a after market powersuply. I discovered that when listening to music whilst the power cord was attached
that this created some audible noise on the audio line.

I assume this caused also the problems with my Megadrum Modul!?
so If you have similar issues this might be worth to check out!
lots of work for nothing because of this noisy power supply


BUT:
I still have a similar issue, but less extreme…
And it is not (really) dependent on power supply or not.

But when I put a bit a preasure on my Megadrum Box it gets instantely better!
which I think is strange…?

Anyone an Idea what is the issue here and how to solve it?

It might be the Piezo not soldered well to the Jack connector?
It might be some strange grounding issues?

Thanks a lot!

Welcome,
The actual number (35 is not high) for threshold doesn't really matter too much though there maybe other ways of adjusting your problem here. Are you talking about false triggering without hitting a drum?

Thanks for your response!

Yes, I was talking about false triggering.

I have my pads connected and I get about 20 hits a second on the rim on all inputs.
The output velocity/ loudness of the hits is quite high (maybe around 40? I don't know...)
It only stops when I have the threshold around 35.

I found that quite high.. I mean I can easily get away with a value of 4-6 on the tip (head input) so why not on the ring (rim) input?
With a threshold that high how can you get megadrum to register soft hits?

However:
I found it wired that:
> in the first case it was clearly caused by the power supply (in my opinion)
> I still have the issue... and it seems to get better when I push down on the enclosure of my megadrum..?
(p.s. it's not me grounding/touching metal somewhere, it's just mechanical preasure on the top of the device..

I thought it might have to do something with eighter grounding connections, or that my ring piezo has a bad solder joint?

In theory it should still detect soft hits even if threshold is high. Does it still show this behaviour when plugged into a different input or with a different cable? Try to isolate the source of the problem. What you say about pushing down on the case makes me think there's a faulty solder joint or maybe a small crack in a PCB track somewhere, and when you apply pressure you're closing the gap.

> cables: it tried an other cable the reaction was the same.

> different input: I just used one stereo mesh pad and changed to where I plugged it in. it was always the same. Tip=Threshold of 4 is fine Ring=I need to raise Threshold to 35 to stop ghost notes.

> About pushing down on the case...Inside it is just really tight with a bunch of cables around and these 4x4 TRS Jack Socket Boards...logically I would think that if there is an issue inside the box it might get worse (not better) if you push down on the case... but your explanation makes sense to.

> maybe it could also be an Issue with the soldering on the Ring piezo itself? since I only used one Pad for testing. Will check that out next. hope I don't need to open the box and resolder all connectors

ignotus wrote:In theory it should still detect soft hits even if threshold is high.

o.k. but how would you need to set it up, which parameters needs to change to detect soft hits?
my understanding was that the lower the threshold the softer the hits that can get interpreted by the module

drumsdibums wrote:o.k. but how would you need to set it up, which parameters needs to change to detect soft hits?
my understanding was that the lower the threshold the softer the hits that can get interpreted by the module

MD takes the difference between threshold and high level and divides it by 128 which will transfer to the various velocities of whatever you may be triggering.

drumsdibums wrote:MD takes the difference between threshold and high level and divides it by 128 which will transfer to the various velocities of whatever you may be triggering.

To me that means that that the lowest value that gets TRANSMITED is 1.
It does not mean that a (very) soft hit (>below the threshold?) gets REGISTRED.

... so the Module will send low MIDI Values... but the Pad is less sensitive > that is how I understand it.

If you all think I can get away with realatively high Threshold values then thats fine. I just need to try it out.
When I adjusted my Pads I had them sometimes not sensitive enough. Thats when I lowered the threshold.

Are there other settings that make the Pad more sensitive to light hits?

1) So you two don't think that there is something wrong with the module?
What I found strange is that it ONLY happens on (all) Ring (=Rim) Inputs and never on the Tip( head)??

Just to ensure we are talking about the same thing.
Pad connected to Megadrum, I don't touch anything, rim triggers like crazy unless I raise threshold to 35.

I think someone had the same iusses posted on this form...need to find that, don't remember if he was able to solve his problem.

It should be possible to set the threshold at a point at which the pad stops triggering on its own but still picks up soft hits. If this is not the case then there is something wrong. The theory goes that this value will vary between piezos, though those from the same batch should behave similarly. Have you set the pads to 'dual piezo' and not to 'piezo/switch'? Just a thought... Maybe you could post a screenshot of your settings for the problematic pad so we can have a look.

ups.. I forgot to add a Screenshot of my megadrum settings of my 12" and 8" mesh drums.

They are now in my other Post on this forum: Pad sensitivity not that great for medium and hard hits
which you can find here:http://www.megadrum.info/forums/viewtopic.php?f=3&t=3122&p=31440#p31440

a side note:
Yes, the Rim Triggers are off (Note 0) on the Screenshot. But I tested it before and that was the value I got (34).

I will need to redesign how I will be able to trigger Rim Shots on my handdrum mesh-head drums.
The Problem is: if I place a regular Mesh-skin on these tunable handdrums. the ring(?) goes over the drum (see image)
so it is not easy to separate ring from head.

I might add the piezo to a piece of wood (ring shaped probably) which I mount to the drum. It I hit this piece of wood, I get a rim trigger.

It is not Ideal, I found that out after I ordered these handdrums.
the other thing to do is to make a mounting "thing" on the handdrums.

I ordered these handdrums from thomann.de (germany). You can buy a handdrum and a mesh head skin pretty cheap.
It might be better/easier to just order the cheapest 8" tom and cut it in half to have two mesh head drums. If you want to do this stuff on your own and need to by some stuff