Help Building Standalone E-drums

I wasn't sure if this belonged to the development section or interfacing, so, if it needs to be moved I apologize. I'm new to Arduino development, and have managed to build an electronic drum kit using the Arduino and the Ardrumo software for MacOS. It works great, but I would like to begin developing a standalone system that could play back it's own samples. I guess what I'm looking for is (a) board(s) or unit(s) I can trigger using the Arduino that would play audio samples at a quality sampling rate. After scouring numerous Google pages I have a feeling I don't really know what I'm looking for or at least not how to search for it. I appreciate your help in this, and if this has already been covered I apologize because using the forum search didn't turn up any results. Thanks in advance.

Adafruit has the "Wave Shield" that will allow the Arduino to play back pre-recorded audio bits:

Also there is the "Voice Shield" VoiceShield, which someone recently made into a sort of sound effects generator Sound Effects Box | Hackaday

I don't know if either of these is fast enough to use as drum simulator, but they might be good places to start. Most of the drum hacks I've seen for microcontrollers are aimed at detecting hits and triggering an external drum-machine/sound-device, rather than actually generating (or even playing back) sound...

Thanks for the help. I'll look into the Wave Shield, and see what the specs are there. The only concern I had with the Voice Shield was the 8khz sampling rate. I'm not sure if that will be in a high enough range to keep the kit from sounding "cheap", but like you said it could be a start.

Also, it's funny that you mention the hackaday article because that was what got me thinking about researching the project again. I looked into it when I first got my Arduino, but it seemed my only route was to buy a drum brain. Although this would be the easiest method, I'm trying to appeal to the budget-minded hacker in hopes that I can build a comparable setup for less. Then, I could share my results with others who may be looking to do the same thing.

I don't know what you currently have together but you're gonna want some piezo elements so you can make the pads velocity sensitive.

Yeah. Like I said, I have a fully working system that is dependent on a Mac/PC, but I would like to develop a cheaper and more open method of sample playback. In other words, I don't want to have to plug my kit into a Mac/PC or buy a $300 drum module. I mean, hey, the latter isn't what we're all about here, anyway. We like to build it ourselves, right?

We like to build it ourselves, right?

Problem is that this sort of application is really not suited to the Arduino. You need much more memory to store the samples and a proper 16 bit D/A to play them back. The arduino's hardware abstraction layer is based around bit I/O rather than port or byte I/O. Not that you can't do it is just that you soon run out of I/O because you don't get a good run of free ones. As you want better than 8 bit sampling you quickly run out of resources.
You need a controller that can be configured to use and external bus and attach some static ram to it. Something like the LPC2103 or maybe a more powerful one from that family. Problem is that those development environments are not so friendly as this one.