Yamaha DTXpress/DTXplorer/DTXtreme

I just saw a pict of the  Hart Prosnare innards along with a schematic and understand why it probably won't work on a DTXpress.  Under  
the mesh head is a approx. 6 inch foam cylinder  (1 inch diameter) positioned in the center that transfers  energy to a 10 inch diameter  
aluminum plate.  The piezo is  underneath this plate.  This probably eliminates the hot spot that Roland mesh pads are know for but 
would be WAY too small of a signal for the DTxpress.  
Roland piezo's are 2 inches from the head with a cone shaped foam material transfering energy directly to the piezo.  
According to this schematic the Prosnare has 3 piezos.  One under the aluminum plate and TWO on the shell of the drum.   One of the 
shell  piezo's and the center piezo is wired in parallel. This is a very curious third piezo.  It would seem every time you hit the rim the center 
sound triggers too?!
Jun

--- In DTXpress@yahoogroups.com, "jtatsuoka" <jtatsuoka@y...> wrote:
> I just saw a pict of the  Hart Prosnare innards along with a 
schematic and understand why it probably won't work on a DTXpress.  
Under  
> the mesh head is a approx. 6 inch foam cylinder  (1 inch diameter) 
positioned in the center that transfers  energy to a 10 inch 
diameter  
> aluminum plate.  The piezo is  underneath this plate.  This 
probably eliminates the hot spot that Roland mesh pads are know for 
but 
> would be WAY too small of a signal for the DTxpress. 

Jun,

Seems plausible. 
  
> According to this schematic the Prosnare has 3 piezos.  One under 
the aluminum plate and TWO on the shell of the drum.   One of the 
> shell  piezo's and the center piezo is wired in parallel. This is a 
very curious third piezo.  It would seem every time you hit the rim 
the center 
> sound triggers too?!

I'm just guessing, but maybe the parallel piezos create a kind of rim 
to pad effect, or, more likely, are used for positional sensing with 
certain voices, via the Roland TD-10's expansion card.

Ed

> 
> I'm just guessing, but maybe the parallel piezos create a kind of rim 
> to pad effect, or, more likely, are used for positional sensing with 
> certain voices, via the Roland TD-10's expansion card.

Ed,
The Roland dual zone mesh pads only have two piezos. According to td-8 and td-10 users on electronicdrums.com,  the only requirement 
for positional sensing is the mesh head piezo to be centered. 

Jun

--- In DTXpress@yahoogroups.com, "jtatsuoka" <jtatsuoka@y...> wrote:
> The Roland dual zone mesh pads only have two piezos. According to 
td-8 and td-10 users on electronicdrums.com,  the only requirement 
> for positional sensing is the mesh head piezo to be centered.

Jun, 

Well, I thought as much, but the three piezos threw me. I've been 
checking out what the Hart lovers at vdrums.com have had to say. 
Surprisingly, no one mentions the third trigger--only the advance of 
the Pro over the Accupad so far as plug n' play is concerned and the 
amelioration of the hot spot. If you get a clue about what the extra 
piezo is doing on the shell from the schematic, please post it. Could 
it simply be providing better coverage of the head? Apparently, the 
Accupad stopped triggering effectively an inch away from the rim. 
I'll stop speculating.

Ed