Pad setup wizard suggestion

[Kabonfaiba]

Unplugged at the cymbal end:

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Also, tested unplugging from Megadrum end = no activity.

Yeah the spasm attack; lucky I caught that on the log so cleanly. Usually I'm playing when that happens.

Let just say that's an ongoing investigation. I've had the whole house electronics tested, I even thought it was the central heating servos a while back (it isn't) completely out of (free) ideas.

The Megadrum is powered over USB from my PC, which is fed from a conditioned extension lead. No other nearby electronics, the USB lead is shielded and run seperated from other power cables. I've put ferrite beads over everything! Basically it's been a mystery for years now but I never plan to go gigging with a Megadrum anyway.

Actually I had plans to purchase a high quality MIDI cable and separate USB adapter when I have disposable cash. I just didn't want to spend that money and not fix it you know, MIDI cables could make the work-flow worse afaik, I like MIDI over USB.

[dmitri]

It appears to me that the switch in the cymbal (being a bigger antenna then just an open cable) picks up some specific (and weird) electromagnetic noise. I may try to filter in the firmware but I need to be able to reproduce it and I don't know how at the moment.

[Kabonfaiba]

I'd appreciate anything Dmitri, thanks.

I didn't mention that I've also lined the inside on the ABS case with aluminium foil tape, taking care not to have any connectivity with the PCB or bare wires, continuity tested okay. So I've attempted the EM shielding where I can. Obviously this hasn't made it better, but not worse either.

You've just given me some inspiration actually. I do have a wireless access point in the vicinity of my drum-kit. Do you think Megadrum is susceptible to noise from 2.4GHz or 5.0GHz radios?

[dmitri]

As far as I can see, it is not MegaDrum itself which picks up the noise but the large switch on the cymbal. I can suggest to put a 1-100nF resistor parallel to the switch to try to suppress this noise.

[Kabonfaiba]

I did my MIDI cable / external USB power experiment yesterday.

It did not solve the noise issue unfortunately, which I wasn't fussed about in the end anyway, since I was more concerned with trying to get MDMFX working through my audio interface MIDI port and it just wasn't having it!

The MIDI log was receiving data with the port open, VSTs triggering as normal, etc. Just couldn't figure out why no Sysex communication was possible. I left it running for 30 minutes in the background for the test and I still got a noise spasm of notes in the log so test over afaik. No other benefits to using MIDI cables, latency was the same, etc. 1 extra cable I could do without, but I'll keep the £10 MIDI cable I guess, as I might have a Mimic in the future, who knows.


I would pay to have some sort of addon PCB which plugs directly between the IDC connector for the jacks that has a series of capacitors for noise filtering, and also some through hole trimming resistors to dial the inputs; say the tip and ring of the first 6 inputs or so? i.e. 12+1 pots on a breadboard; 0 - 100kΩ variable, enough for kick, snare and 4 toms, and an extra pot for hi-hat pedal too, which replaces the need for that fixed 10k resistor, for some people.

Small enough to fit neatly inside existing users Megadrum cases. A set and forget solution. Possible for £25 incl post?

[dmitri]

About cheap USB MIDI converters: unfortunately they don't support Sysex properly if at all. When I do testing of modules/kits before posting I test standard MIDI functionality using a USB MIDI interface I developed myself and which fully supports Sysex:

20171203_175033.jpg

Some may recognize the silver cable with MIDI In/Out which I nicked from one of such cheap USB MIDI converters.

[ignotus]

I would pay to have some sort of addon PCB which plugs directly between the IDC connector for the jacks that has a series of capacitors for noise filtering, and also some through hole trimming resistors to dial the inputs; say the tip and ring of the first 6 inputs or so? i.e. 12+1 pots on a breadboard; 0 - 100kΩ variable, enough for kick, snare and 4 toms, and an extra pot for hi-hat pedal too, which replaces the need for that fixed 10k resistor, for some people.

If you can use a soldering iron it's not too hard to make a board with a few trimpots. I made one with 32 back in the day but I'd sooner jump off a cliff than do that again...

[Kabonfaiba]

Ah, maybe I need two cables to support sysex. I thought I could do send and receive through one cable, but I guess 1 port = two cables.

Seeing MIDI and CTRL as two separate ports on my Octa-capture threw me off.

Hey ignotus, yea I recently invested in upgrading my soldering kit; got some helping hands, tip cleaner, flux. Haven't even used the damn thing yet. I have money but no time these days. I will spend months researching how to even start such a project.