Cutting a giant hole in my bass drum's shell

Les Ismore

Platinum Member
Yowzer, heeeello insides!!!

How big is that hole?

And you did it in the dark?

Its not centered perfectly, we notice that stuff here on DW.

Cool, a good place to stash your wallet at gigs
 

larryace

"Uncle Larry"
Don't those vents have to be vented outside to meet Code? :p

I know when snares are vented, it really drys out the tone. It makes it sound more in your face too.

I'd like to see some kind of control, picture a camera aperture, so you could customize the amount of venting for the room.
 

Andy

Administrator
Staff member
On most ply shells, even the thin ones, something around 4" diameter in the centre of the shell won't make much structural difference so long as it's kept away from stress points such as spur mounting brackets. Exception may be 3 ply shells that are inherently less rigid than shells with more plies.

Solid shells are a different matter. Never do this on steam bent single ply or hollow log. Segmented & stave should be ok, but should be avoided on thinner shells.

Ok, that's the structural stuff. Sonically, a large shell port makes a lot of sense for those wishing to maintain a full reso head but keep playing characteristics close to a ported head. The difference in sound, more especially the fundamental, will depend on the shell construction. With most ply shells, any difference in length of fundamental will be minimal, & not really worth considering. On more resonant forms, there is a degree of disturbance to the shell that can equate to reduced fundamental prominence by either shortening the note and/or introduction of higher overtones. Muffling pretty much negates those changes, so any real concerns only apply to those with wide open bass drums.

As a design note - outside of the benefit of internal mic'ing, there are other shell venting options that offer the desired effect but maintain shell integrity more evenly, & retain fundamental profile.
 

larryace

"Uncle Larry"
Read this post again, only substitute the voice of Sheldon Cooper in your head.

Andy you're the Sheldon Cooper of drum building.

On most ply shells, even the thin ones, something around 4" diameter in the centre of the shell won't make much structural difference so long as it's kept away from stress points such as spur mounting brackets. Exception may be 3 ply shells that are inherently less rigid than shells with more plies.

Solid shells are a different matter. Never do this on steam bent single ply or hollow log. Segmented & stave should be ok, but should be avoided on thinner shells.

Ok, that's the structural stuff. Sonically, a large shell port makes a lot of sense for those wishing to maintain a full reso head but keep playing characteristics close to a ported head. The difference in sound, more especially the fundamental, will depend on the shell construction. With most ply shells, any difference in length of fundamental will be minimal, & not really worth considering. On more resonant forms, there is a degree of disturbance to the shell that can equate to reduced fundamental prominence by either shortening the note and/or introduction of higher overtones. Muffling pretty much negates those changes, so any real concerns only apply to those with wide open bass drums.

As a design note - outside of the benefit of internal mic'ing, there are other shell venting options that offer the desired effect but maintain shell integrity more evenly, & retain fundamental profile.
 

porter

Platinum Member
Read this post again, only substitute the voice of Sheldon Cooper in your head.

Andy you're the Sheldon Cooper of drum building.
"Do not make comments that are [...] insulting or disrespectful to any individual..."

Looks like you're goin' down, Larry. ;)
 

GruntersDad

Administrator - Mayor
Staff member
Wow. measure twice, cut once. It is off center. And is that hole on the bottom where the sound will just leak into the floor? Another thing I thought of which may or may not be relevant is that on the reso head the sound is going forward, and on the shell it is going upward. Now if the drum is mic'ed it may not make a difference other than to say why not just install the mic inside and for get the hole. But since the hole is already there, ouch, we'll just have to wait and see. I'm thinking if this was the way to go we would have seen it earlier.
 

GruntersDad

Administrator - Mayor
Staff member
Don't forget that a big portion of the KickPort's sound is the mass it adds to the reso head ... you won't get that dampening when the KickPort is mounted in the shell.
the other effect the Kickport has is the fact that it is opposite the batter head in the direction of the majority of the sound waves I expect, not 90 degrees to the head.
I just don't see this making much difference other than allowing you to bury the beater.
 

Les Ismore

Platinum Member
the other effect the Kickport has is the fact that it is opposite the batter head in the direction of the majority of the sound waves I expect, not 90 degrees to the head.
I just don't see this making much difference other than allowing you to bury the beater.
The port could be anywhere actually, low freq's are non directional, outside or inside an enclosure. The OP is suggesting a tuned port which involves a tube. Agree the bottom of the shell isn't optimal for sound IMO, but near the bottom may be.

KICKPORT is porting some BD batter heads with their devices showing low freq's can be accentuated in this way.
 

Attachments

ThumperJim

Senior Member
Yowzer, heeeello insides!!!

How big is that hole?

And you did it in the dark?

Its not centered perfectly, we notice that stuff here on DW.

Cool, a good place to stash your wallet at gigs
No, it's offset for a reason...Had to clear the base of the mic stand. But I did it because I like to use a full front head sometimes, and to me, it yeilded a bit more low end. Kinda like Yamaha and their 5 vent holes on some bass drums. Has served well for 13 years, no negative effects whatsoever. I think its 4.5" hole...its been a while since I dood it.
 

Jankowske

Senior Member
HOLE SAW ACQUIRED!

One of my dad's friends apparently had a nice harbor freight set, so he let us borrow the 5" for a couple days. I am very tempted to fire up the drill tomorrow. Unfortunately, this may render my experience utterly useless to everyone else here since I'm pretty sure I don't have any decent intact resos floating around anywhere, and I can just about guarantee that GC doesn't have a 22" diplomat fiberskyn in stock. So much for objective before/after clips. However if I can find one of my old SKIIs that split on the front ply, I might be able to do some razor blade surgery on it to make it into a 7-mil one ply (maybe even a backwards "powerstroke!")


On most ply shells, even the thin ones, something around 4" diameter in the centre of the shell won't make much structural difference so long as it's kept away from stress points such as spur mounting brackets. Exception may be 3 ply shells that are inherently less rigid than shells with more plies.

Solid shells are a different matter. Never do this on steam bent single ply or hollow log. Segmented & stave should be ok, but should be avoided on thinner shells.

Ok, that's the structural stuff. Sonically, a large shell port makes a lot of sense for those wishing to maintain a full reso head but keep playing characteristics close to a ported head. The difference in sound, more especially the fundamental, will depend on the shell construction. With most ply shells, any difference in length of fundamental will be minimal, & not really worth considering. On more resonant forms, there is a degree of disturbance to the shell that can equate to reduced fundamental prominence by either shortening the note and/or introduction of higher overtones. Muffling pretty much negates those changes, so any real concerns only apply to those with wide open bass drums.

As a design note - outside of the benefit of internal mic'ing, there are other shell venting options that offer the desired effect but maintain shell integrity more evenly, & retain fundamental profile.
This is what I was thinking/hoping. My shell is medium thickness and I only have one tom mounted on it, so not too much weight. Once I can afford a rack I will most likely remove the mounting hardware completely and maybe make a nice wood patch thing to cover the old holes. And I use my bass drum pillow about half the time, which is one of the reasons I like having a large hole (replacing and removing it all the time.) A bit quieter for practice and more easily mic'ed for shows with the pillow, and then wide open for band practice and whenever the urge strikes.

Video the cutting of the hole if you can, that'd be great entertainment.
Yes, yes, I'm sure you'll all get a good crack out of this. Hopefully my resident guitard knows where his camera thing is...or maybe one of these cameras can take video.

I'm still considering doing a practice run on my "other" kit; might go and retrieve it tomorrow. Not exactly sure what there is to be learned from it, though. I doubt the poplar will cut as well as the maple, and it's got that wrap on it, too.

And thanks for sharing, ThumperJim. 13 years and no problems is good news. Guess I won't have to worry about my shell going out of round or anything. Do you have any advice for cutting? Did you use a hole saw or what? And do you mean that you're kind of setting the hole over the mic stand? That's pretty sweet.
 

ThumperJim

Senior Member
HOLE SAW ACQUIRED!

One of my dad's friends apparently had a nice harbor freight set, so he let us borrow the 5" for a couple days. I am very tempted to fire up the drill tomorrow. Unfortunately, this may render my experience utterly useless to everyone else here since I'm pretty sure I don't have any decent intact resos floating around anywhere, and I can just about guarantee that GC doesn't have a 22" diplomat fiberskyn in stock. So much for objective before/after clips. However if I can find one of my old SKIIs that split on the front ply, I might be able to do some razor blade surgery on it to make it into a 7-mil one ply (maybe even a backwards "powerstroke!")




This is what I was thinking/hoping. My shell is medium thickness and I only have one tom mounted on it, so not too much weight. Once I can afford a rack I will most likely remove the mounting hardware completely and maybe make a nice wood patch thing to cover the old holes. And I use my bass drum pillow about half the time, which is one of the reasons I like having a large hole (replacing and removing it all the time.) A bit quieter for practice and more easily mic'ed for shows with the pillow, and then wide open for band practice and whenever the urge strikes.



Yes, yes, I'm sure you'll all get a good crack out of this. Hopefully my resident guitard knows where his camera thing is...or maybe one of these cameras can take video.

I'm still considering doing a practice run on my "other" kit; might go and retrieve it tomorrow. Not exactly sure what there is to be learned from it, though. I doubt the poplar will cut as well as the maple, and it's got that wrap on it, too.

And thanks for sharing, ThumperJim. 13 years and no problems is good news. Guess I won't have to worry about my shell going out of round or anything. Do you have any advice for cutting? Did you use a hole saw or what? And do you mean that you're kind of setting the hole over the mic stand? That's pretty sweet.
I used a Rotozip, made a template with a Compass first, penciled onto the shell. The mic stand is the one with the offset weighted block as a base, and I f I centered the hole, it would have lifted the drum, and the pedal off the floor. I did all this when the drum was 24" Deep too....Sounds equally as monsterous cut down to 16".
 
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anzi

Member
I've had a hole in my Premier 60's 20x14 bass drum for a long time now. I would guess that I cut it around ten years ago, and it has caused zero problems. I'm from Finland so I saw many Kumu drums with the side hole that sounded awesome. And my bass drum just sounded dead with a port on the head, and most sound guys complained about not having a hole in my head, so I took a saw and cut a hole in the shell. If I remember right, it's 4 inches. For me, it makes the drum more versatile. I can get a nice boomy sound miked in front of the drum, and more attack miked from the inside. It's also nice in small stages, because I don't have to have a mick stand in front of the drum, that some one would displace anyway.
 

Jankowske

Senior Member
Here it is:













And the "hole":





The heat gun thing worked great. I didn't really get a good shot of how the kickport matches the shell's curve now. Oh well. Anyways, I just put it in the hole after it was cut and started softening it up with the heat gun (on "low"; the box said 572 F), moving in slow circles around the edge. I had a leather glove on my other hand and once it softened up I just kinda pushed and rubbed it until it matched the shell's radius. It turned out better than I thought it would.

I originally planned on removing the gaskets and rubber thing and securing it with silicone caulk, but the rubber thing still worked the same so I just went with it. Whatever dampening it may be doing to the shell has nowhere near the efffect on the sound that it being stuck to the head had.

Also I love this new head. I had the powerstroke amb fiberskyn before, but it seemed too thick and dull most of the time. This time I got the plain diplomat fiberskyn. When I took the head out of the box, I tapped on it a bit and instead of a plasticky thwack-thud-rattle it had this really papery flutter sound. As I was tuning it up sans-pillow I got this awesome thunderous sound that reminded me of big concert bass drums if not a bit thinner. Once tuned and with the pillow it just sounded really really good. The resonance it still has is tasty instead of annoying. Not sure if it's for all metal drummers, but I am very satisfied.

Overall I would say this worked out very well. High five, great success. Also for those of you dying to see some punk kids plow a hole saw through a perfectly good bass drum, a seven-minute-long video is forthcoming.
 

porter

Platinum Member
I did it as well, 2.5" hole. I put new heads on as well so I can't specifically comment on how the sound changed, but with two full head, unmuffled heads (clear ambassador and fiberskyn ambassador) it sounds pretty great. I had a 2" hole in the previous reso head (also unmuffled) and it now seems to be between that sound and a totally open one with (to me) the preferable feel of the former. I'm excited to mic it up as well and see how it translates.

Also, a quarter inch is a lot thicker than I imagined.
 

Jankowske

Senior Member
So I took my kit from my "recording" room yesterday (small, pretty dry sound) to my band's practice space (bigger and untreated) and I got to hear what my kick really sounds like now. It's TREMENDOUS. The difference before was good enough, but now I can really hear how beefy and solid that thing is. I am now a very firm believer in the solid front head.

I did it as well, 2.5" hole. I put new heads on as well so I can't specifically comment on how the sound changed, but with two full head, unmuffled heads (clear ambassador and fiberskyn ambassador) it sounds pretty great. I had a 2" hole in the previous reso head (also unmuffled) and it now seems to be between that sound and a totally open one with (to me) the preferable feel of the former. I'm excited to mic it up as well and see how it translates.
I was gonna get before/after clips of mine but I cut the hole before getting the new reso, so it wouldn't have been a very useful comparison. Ditto on getting to hear it mic'ed up soon. What size is your kick? And what side do you have each head on?

Also, a quarter inch is a lot thicker than I imagined.
Yes. It took me over five minutes to cut through that stupid shell. Granted I was going pretty slowly and carefully, and 5" is a pretty big hole saw, but seriously. I guess that maple plywood is a bit tougher than whatever crap I'm used to cutting.
 

porter

Platinum Member
Mine is a 20x15" stave Purpleheart, 1/4" thick. Clear ambassador batter. Before, I was using a Coated G1 batter and Smooth White Ambassador reso with a 2" hole. I'm going to try the coated G1 sometime as well with this new setup.
 

CommanderRoss

Silver Member
I thought of doing this just below the spur bracket. I use (and love) the KickPort. Always have. I have a cheap kick I just might do this with and see how location affects sound. I'll bend the KickPort to match the shell and see what happens.

I love experimenting with drums like this and there are plenty of cheap kits being sold out there to try this on.
More to follow.
 

axisT6

Senior Member
Look closely!



28" Reso Heads are $$$ and I wanted to get a full sound out of them. I put 4" ports in each of the 28x22s shown.
 
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