Slap sound out of Kick Drum

[roadking]

I completed my kit about a year ago and have been pretty happy with the results except for the kick drum and the Hihat controller. I use a converted 22" kick and a FD8. The problem with the kick is that I have sensitivity set to 10 and if I play it soft it sounds like a nice bass drum, but, if I kick it just allittle too hard it gives me a slapping sound. I've always had this and its now driving me crazy.
I wired the kick the same way I wired all the toms and after playing with all the settings on the kick I've given up and now its time to turn to the pros. Is the kick supposed to be wired like all the rest or is it different? Also, could I be getting too much concusion on the piezo as its just off center behind a 2" stiff foam pad. As usual, any help would be highly appreciated. Thanks RK

[racer52]

I am not a pro at this, but I did have some issues with my bass drum too.

The trigger is the same basic design and wiring - just no rim trigger/piezo.

Heavy foot work would depress the head far enough that a second trigger occured on the rebound from the head.
My solution was to move the trigger to near the edge of the drum where the head did not move in and out as much. Maybe about 1 to 2 inches from the shell. this also lessens the impact to the trigger and helps it last longer.

If you use a double pedal - position near an edge that is the same distance from both beaters (for equal signal for the same power to each pedal)

Hope that helps.

[roadking]

Thanks Racer..
I repositioned the piezo and now I don't get that slap unless I turn up the sensitivity. The only problem I have now is that I still think I'm getting too much sensitivity. I have to play with moving the piezo here and there to find the best place to permanently position it.
Thanks Again RK

[racer52]

Glad that helped Roadking - here are someother thoughts about your sensitivity

How is the cone fastened to the piezo and how is the piezo fastened to the support?

the ratio of the mating surfaces of the two sticky tapes on the top and bottom of the piezo will affect sensitivity.

for ex. lets say that your cone is fastend to the complete piezo -to the white part and all of the brass part. Ie: if the piezo is 30 mm in max diameter, you would be using a 30 mm diam piece of tape to fasten the cone. And the mounting tape below is only the size of the white part of the piezo. If that were the case, and you wanted to decrease the signal produced, you could enlarge the the lower tape to the same 30mm diameter -this would cause less of the piezo to vibrate and a smaller trigger signal would be produced.

another factor is the hardness of the foam cone itself. harder cones transfer more shock strength that a softer cone.

caution: the more you mess with a given piezo the more likely you are to crack it - then you are chasing a different problem. be sure that your piezo is sound.

[roadking]

AS for the piezo, its a 35mm and its fastened to one of the cross
members using two sided tape thats the same size as the ceramic. I'm not using a cone but a foam cylinder from pintech that is attached to the ceramic part of the piezo by two sided tape that is also the same size of the ceramic part of the piezo.
The kick now triggers better but the sensitivity is still alittle too high.
Thanks for all your help.
RK

[racer52]

... The kick now triggers better but the sensitivity is still alittle too high.
Thanks for all your help.
RK

You are welcome RK - wish I knew more about this stuff

Hmmm... Running out of ideas for you. You could use a smaller piezo.
Maybe someone else can offer more... What typ of drum brain module are you using? I only have used a TD20 and the trigger sensitivity in it can be run from 1 (the lowest) to 32 (super sensitive setting).

I know that head tension needs to be tight.

[roadking]

I use a TD20 and even if I have the sesitivity set to 1 it doesen't make any difference. The drum is a 22" Ludwig and I have a Hart head on it. Its kinda wierd cause I've been fiddling with all the settings and last night I got into the min volume and that made a difference in the sound it produced. It seemed that whatever sound I assigned to the bass worked better if the min vol was set to 0, there just seemed to have less boom to the bass. But in the end, it doesn't matter if the sensitivity is set to 0 or 32 I basically get the same sound. Wierd Huh? I just don't have the time to spend with my module and I know thats a big issue here and if I can scrape some time together I'll learn more about the TD20 and cure allot of my problems.
Thanks RK

[racer52]

Had a thought last night -try a softer "cone" material. also the "cone" needs only to barely be above the rim adge. I have mine about 1/16 to 3/32" .
I use a straight edge across the diameter of the shell to view the gap.

Happy New Year!!

[Ruffneck]

Hi,
after reading your posts it sounds that your bass piezo is too "hot", ie producing too much voltage. I would suggest you to add a voltage divider to your piezo. Have a look here: http://en.wikipedia.org/wiki/Voltage_divider

You would connect the "hot" lead from your piezo to Vin and your "cold" to gnd. For R1 and R2 you could use for ex. 10kohm resistors and this will halve your voltage output. It really doesn't matter what size the resistors are as long as they are the same.

For a 25% reduction of voltage use 10kohm for R1 and 30kohm for R2. For a 75% reduction of voltage use 10kohm for R1 and 3,3Kohm for R2.

Hope i got my maths right.....

/Kari

[roadking]

Hi Ruffneck
After reading your post I went to the site you refered me to and Holy Einstien, your kidding right? If i coould understand that I'd invent a drum module that EVERYONE would like. Anyway thanks for the advise but I think I could spend hours on this method and still not be where I want to be.
I'm thinking that the problem is the size and placement of the piezo.
Thats where I'm going next. Like Racer said, he placed the piezo closer to the edge and that made allot of difference in the way it played.
Anyway, thanks again for you advise.
RK

[Ramsh]

Did you try the different trigger curves?

[Ruffneck]

Hi Ruffneck
After reading your post I went to the site you refered me to and Holy Einstien, your kidding right? If i coould understand that I'd invent a drum module that EVERYONE would like. Anyway thanks for the advise but I think I could spend hours on this method and still not be where I want to be.
I'm thinking that the problem is the size and placement of the piezo.
Thats where I'm going next. Like Racer said, he placed the piezo closer to the edge and that made allot of difference in the way it played.
Anyway, thanks again for you advise.
RK

It really is not that difficult at all. Go and buy 2 10kOhm resistors. Connect it like in this picture:



You connect the leads from the piezo on the left hand side (Input voltage on the picture) and to your TRS connector on the right hand side(Divided voltage in the picture).

Give it a try, it is not at all hard and is really worthwhile as i think your pad will work ok after this.

/Kari