I finally got a decent tone out of my cocktail set today!
I had two types of foam I was working with--one type was 1" green stuff from a craft store, and the other was 1 1/2" studio soundproofing foam.
First, I worked at getting a good bass tone with no top head on. My drum diameter is 15", and initially I had a 15" foam disc on top, but I found that cutting that disc around the perimiter by about 1/2" gave me a much nicer tone. The foam jumps a little and then falls when I kick the pedal, so I get a round but thumpy tone. With a slightly smaller disc of soundproofing foam on top of that I got a nice low, disco-ish kind of tone--not what I'd like on a normal set, but for a cocktail set, the tone is punchy and deep.
With a good bass tone in place, I checked to see what kind of snare rattle I'd get, first by tapping the pedal and touching the snares (they rattled a lot), then by resting the snare head without a rim for a double check (I was right). So I set to work on a baffle. I wanted as much of an air chamber as I could get out of the bottom head for the lowest tone possible. I have a 2 1/2" vent below the snare head and another about 1/3 of the way up the drum from the bottom. My hope in drilling those way back when was that the snare would open up a bit and that baffle would lose some of the pressure from the bass drum soundwaves. So I made a baffle with a thin piece of masonite. The bottom of it is covered with a 15" disc of soundprooofing foam, and the top with a 15" disc of the green foam described earlier. The baffle is held in place by the reinforcement ring in the middle of the drum and ends right below the top sound hole. I tested the baffle by putting the top head on without a rim and got a little snare rattle. I fixed that by clipping about a centimeter off the snare fan, so that the snares fell short of the center of the drum by about an inch, and ran about three inches total. I made sure that when I cut them, the snares turned down, not up, to eliminate that annoying scraping buzz they can sometimes get.
When I put the top head back on at a medium tight tension, the snare sound was very good and the snares barely got any bass rattle. The shorter snares dropped the sensitivity of the top head, but I found that hitting in the same zone as the snares made a very crisp, articulate, piccolo like sound. The other zones sound a bit more like a field drum.
The drum balances out very well tone wise--the 17" remix ride, the 12" 70's A's hi hats, the bass tone, the snare tone, and the 10" tom tone all work at about the same volume level and all share the same degree of articulation.
I played with miking a bit and found that the sound holes are not the best place to mic the drum. A bass mic pointing upward underneath the bass head worked nicely, and an SM57 between the snare and tom will do the trick perfectly. EQ goes a long way.
All that remains is to take some pictures for the website (I need a digital camera first) and to finish the drum in silver sparkle wrap. I'm going to try to use auto door trim to trick out the perimeters of the sound holes, and I've got to figure out something for the seam where the two marching drums meet to become one cocktail drum. I'll call Precision Drum Co. to see what they can recommend.
By the way--to anyone wanting to build a cocktail set on the cheap--even though I got the marching drums for free and they are easy to come by, for about the same amount of money it will cost to wrap the drums, I could have bought a raw Keller shell and just rubbed a nice wax finish on it. The old mahogany veneered maple Ludwig shells are very nice, though, and I dig that I have a cocktail set and a drumset now made from recycled high school marching drums. For about a $250 investment, I've made a 10/15/26" drumset and a cocktail set, all with maple Ludwig or Keller shells.
Will