My Pad is too hot!

[Rob]

I would really like to get my hands on one of those drums so I could do my own testing. They don't ship to Taiwan and they didn't reply to request to add a shipping option to Taiwan, unfortunately.

[thenewdrummer]

I would really like to get my hands on one of those drums so I could do my own testing. They don't ship to Taiwan and they didn't reply to request to add a shipping option to Taiwan, unfortunately.

I have a their crossbar trigger for 13'' snare if you're interested since I wasn't able to make it work it's sleeping in it's box.

It's the same as the one in the snare except with less spoke.

https://jobekydrums.co.uk/product/jobek ... r-trigger/

[mprinz]

Hi Rob,

with this setup - using trim pots - I got a good response with respect to max. output, on the drum-tec like snare pad.

VDrums.com - How to reduce piezo output?

With regard to the equation R2/(R1+R2) is equal to new output and your comment on the slower decay,
I could or should use quite small trim pot values?

Now I have an output of 84% using a approx. 50 kohm pot (8.6k/44k). That's what I got here.
What would be your choice? Is there a minimum resistance required between tip and ground?

[Rob]

You're in unchartered territory. None of my pads are too hot, so I have not really played around with trying to attenuate signals. I think your best bet is to just play around with things and find what works.

[mprinz]

Yup. I see.

But you see, some discussions took place an the vdrums forum.
I actually read that the medeli pads got those attenuation resistors already build in.

But I just wanna hear a good advice with respect to your input stage and which values make electrically sense.

Regards

[mprinz]

As mentioned before I found this:

AlesisDrummer.com
and
VDrums.com

And this evening I ripped of the trim pots and took two 150k and a 20k and put the 20k in series with the head sensor and one 150k parallel to it.
The other 150k resistor I put in parallel to the rim piezo as shown in the VDrums forum.

And - it's like - it feels like every thing runs perfectly. Not the noise "issue", that didn't change.
The gain should be at approx. 0.88 ... nice and the positional sensing feels much smoother.
You know, the orange circle position indicator is not jumping that much.

It's like the cherry on the cake!

Somehow the coupling of head and rim piezo via the 150k ohms to ground ... is necessary?
Maybe I have to change the 20k to higher values, because ... it could be a tiny, little more signal in that config.

Now I am interested if other brands are using those resistors as-well.
Roland, drum-tec ...
I know about those in cymbal switches or yamaha 3 zone pads...

[mprinz]

Hi guys,
hi Rob,

I am still messing around with the DIY snare pad.
It needs to heave the right ratio of head and rim signal amplitude.

If it is not ok, I can barely hit the rim (only the rim) and get huge velocities of the sidestick but can't trigger a rimshot
or the other way I have very low velocities on only the rim and can trigger the sidestick only with the stick resting on the head
and get nice rimshot triggering.

Now I put only a 10k resistor in parallel to the head piezo and its fine too.
Is there any reason not to to this?

I mean, this will also reduce the sensitivity, doesn't it.

Your input stage: Did you use some caps to filter certain frequencies.
I have seen a few in the internet that are doing so.

And for the sake of completenes, I will change the 27mm piezo to 20 mm.
Maybe, when I change the cone ... sometime.

Greetings

Manuel

[Rob]

Hi Manual,

It's really hard for me to troubleshoot your settings without actually seeing the settings--consider attaching screenshots. As for the filtering, eDRUMin only filters out extremely high frequencies (cable noise).

Regards,
Rob

[mprinz]

No, it's not troubleshooting, it's tweaking.

I think - I am really fine just for playing...

But I was still thinking about your post in that thread:

Jobeky snare too hot / positional sensing

Just a few more notes. There's a tradeoff by using that resistor. While it does allow the device to process hotter signals, the decay of the pad is prolonged (i.e. slower rolls and buzz rolls) and the precision of hotspot suppression goes down. In order to get the best result possible results, use the lowest value possible. While not attenuating the signal that much, I find find that using a 6.2k resistor strikes a very nice balance, although that might not be enough attenuation for you.

And I started to investigate the frequency dependence of resistors. There is one, but only for very, very high frequencies.
Then: How to model a piezo in a circuit. I learned that it can be seen as a capacitor - in first proximity.
So you may want to say that the discharging of this piezo-cap is slower, when draining it through a resistor?
Further I thought: Ok, if that's the case lets try a resistor parallel to the piezo-cap, so short out some current
and get a weaker signal at the input. And since I saw a lot simple circuits where the sensitivity is set by variation of the load resistance ...
usually it is 1 Mohm, I thought to give that a try.

And I just need to know: "ok, that's ok and won't kill anything." or "puhhhh, nooooo, please, use the voltage divider only!"

[CapCrunch]

I can solder OK (like for making guitar cables, piezo pads etc.) but know little about electronics and parts like these. Could you give an example of a resister that is a good starting point for a too hot diy pad (27mm). Like on Amazon.Com? Then I could just order some and experiment. Thanks.