E-drum Dynamics - How Does It Work ??

[tcraw1010]

QUESTION:
You know how Roland V-Drums are capable of playing dynamics - i.e. soft tap produces a soft "ghostnote," while a hard hit produces a near rim-shot sound . . . as close to a "real" drum as you can get.

Is the ability to do that in the drum module ... or is it in the way the sensor is set up within the e-drum itself?

In other words, can someone create a DIY e-drum, using the basic piezzo/bridge set up that JLee and disinformation have used, and still get the dynamic sensitivity out of the DIY drum using, let's say, TD-8, TD-10 or TD-20 ???



TOM

[tcraw1010]

Jon . . . disinfo . . . . Where are you guys ??? :(




TOM

[torre_awesome]

i most certainly have been able to set my kit up to respond to ghostnote and dynamics. once your bridge is set so that the cone engages with the mesh head, but does not dig into it, there really isn't to much left to adjust on the drum side, it all just module settings (unless something exceptional happens, like a bad piezo that needs to be chaged.)

i am using a TD-5, which is the old school version of the the TD-6. All the sensitivity adjustments I do are really just to reduce cross talk. in my expirience, my module receives every strike i, no matter how light. however, if the module is left open like that, it will start playing notes that i didn't, so it is neccessary to filter stuff. even on my td-5 (which is from '94) there are a friggen crap ton of settings that i have to go through to set a threshold.

when all said and done, my drums pick up all but the lightest hits, and pick up rolls very succesfully. There are some exceptions though. if intentionally sit down and try to dupe the peizo by playing as light as i can, i can play and not have it get picked up. I do not hit very hard, but when i sit down and intentionally play 'hard' and then compare it to say 'as hard as i can play without being abusive', the output is the same. this is because i have my settings set that the cap when i start hitting kinda hard, and after that, there is not more output to give.

also, if i play open press rolls as fast as i can with the intention of only getting the module to drop a note, i can do that too (this is only for presses as fast as i can go, I haven't been able to get it to drop double stroke rolls.) but for the most part, it plays dynamics and catches anything i would do in a standard set.

[JLee]

QUESTION:
You know how Roland V-Drums are capable of playing dynamics - i.e. soft tap produces a soft "ghostnote," while a hard hit produces a near rim-shot sound . . . as close to a "real" drum as you can get.

Is the ability to do that in the drum module ... or is it in the way the sensor is set up within the e-drum itself?

In other words, can someone create a DIY e-drum, using the basic piezzo/bridge set up that JLee and disinformation have used, and still get the dynamic sensitivity out of the DIY drum using, let's say, TD-8, TD-10 or TD-20 ???



TOM


Sorry, I have been having a little trouble logging onto the site in the past day or so. Not sure if it is a computer problem on my end or what.

I am pretty sure that the ability to differentiate as far as dynamics are concerned comes from the module itself. Now, there are various degrees to which you can help this happen. For example, if you damage the piezo crystal IN ANY WAY before mounting it to the plate, you will likely diminish its receptivity even if it is not damaged to the extent of not working. Also, I still think the springs help somehow in this regard, although i lack the engineering knowledge to say exactly why.

As you go up the evolutionary ladder of modules, I have little doubt that their ability to pick up dynamics increases as well. Unfortunately, so does the module price. Now, to really be able to pick up on the full range of dynamic possiblity, you would have to have an amplification system much better than the one that comes with the module itself. With my setup, the DmPro is a good module, but too quiet when run without a mixer. As a result, I am sure I am losing some of the higher volume response I would have otherwise. Going to solve that one once I have the cymbals and kick drum issues resolved.

[jrfrond]

The module itself is responsible for dynamics and position tracking, but position tracking is dependent on the correct sensor architecture. A standard piezo trigger glued to a baffle bottom, as is typical on most standard pads, has too broad a pickup pattern to allow the position tracking to work correctly (it WILL however, track dynamics). The Roland system depends on a point-contact at the head's dead center, hence the use of the foam cone attached to a piezo.

All Roland V-Drum modules, including the TD-8, 10 and 20 will track position and velocity with this system. However, if you are using, let's say, and Alesis module, which does not have the position sensing feature, it won't work.

[JLee]

I know in the case of my kit, I don't have absolute ability to control position tracking - some, but not all that would be found in a really high end kit. However, I do have the ability to control dynamics on all of the pads. The "gain" setting goes a long way towards this function. If you set the gain too low, you don't get the triggering you want to begin with. But if you set the gain too high to start, you will not have the ability to discern between ghostnotes and full fledged slams on the snare, because even on the lower velocity the meter will "peg".

I readjusted all of my gain settings on my toms immediately after talking to the Pintech technician, and it made a big difference. Ironically, I had called him about the ride cymbal that I bought, and that was one piece that could not be helped much by changing the settings.

[jrfrond]

The REAL problem is that the two common triggering systems basically suck. Piezo trigger, which is what is used on almost all pads ever made (except for Simmons' SDX) is peaky and unreliable over the long run, plus is prone to crosstalk, noise triggering, etc. Careful balancing of all trigger parameters is required to get individual pads to respond well and adjacent pads not to cross-trigger. In other words, a basic pain-in-the-butt.

FSR or "Force Sensing Resistor" is a layered material that Simmons used in the SDX and PortaKit pads, as well as being used on all versions of the DrumKat. While it provides excellent triggering at first, over time the layers bubble and separate and you lose the low-end dynamics, plus it needs a voltage source to work.

Roland really has the piezo triggering system down to a tee on the V-Drums, but it still isn't perfect. The mesh heads are actually part of the trigger isolation system, as they do not resonate at all. Until some company does massive R & D and comes up with a radically new trigger system that isn't finicky or prone to breakdown, we'll have to sweat what we've got.

FWIW- Korg's WaveDrum had a superior "Sensor Net" trigger system to sense position and dynamics, but it was too expensive to implement for complete kits.