Enlarging Speaker Hole

[agedhorse]

The port tubes are 4" diameter and 5" long.

Are they the same on both cabinets? If not, the tuning will be different.

 

[Shishka Bob]

A router is the best way to maybe ruin those speakers by using them in the wrong cabinets.

 

[DJ Bebop]

Except that most routers won't fit the baffle setback into the cabinet.

Rotary rasp (or drum sander with 50-60 grit) and chamfer the top edge all the way around at about a 30 degree angle from vertical.

Be sure the drivers will work well BEFORE doing this modification, it's rather irreversible and the math is a lot easier to do than finding out that it's not a great match with the cabinet.

I had to do this once. Drill with a drum sander bit, round and round against the rotation in the hole.
Done.

That's what I mean, all of what agedhores said

 

[Matthijs]

Another way is to put a dummy baffle with the correct size in front of the baffle. This is close to reversible if you want to spare the cabs.

But I also agree: it might be better to build a dedicated cab around those speakers.

 

[Matthijs]

A quick look at tl606 plans tells me they have much smaller and shorter ports. Tuning is probably very different from your cabs. Maybe if you plug one port you’ll get in the ballpark, but those speakers deserve better. Have someone do the math for you.

 

[Downunderwonder]

The tuning issue is easily remedied with alternative port length.

You could get creative with a router and install a temporary bridge across the existing hole for a centre point to swing the router off.

 

[Slevage]

A router with the correct bit would be the easiest.

Or the most destructive in the wrong hands.

 

[Relsom]

Aside from matching the driver to the enclosure, maybe adding another gasket will stand the frame off of the baffle enough to mount it flush..... use longer screws.

 

[Plain Old Barry]

Two passes with a router...

#1 uses the existing hole to cut a rabbet to the proper size.
#2 removes the lip using a flush trim bit following the rabbet cut in step one.

Perfect fit!

 

[agedhorse]

Router will work until it bumps into the edges of the cabinet. The baffle is recessed over an inch...

 

[Two-Spirit]

I'd do it with a dremel and keep trying to put the speakers in, It need to be tight.

 

[agedhorse]

It doesn't need to be tight. It needs to fit.

 

[Spacecase]

Except that most routers won't fit the baffle setback into the cabinet.

You'll need to make a jig and temporarily attach it to the inside of the cabinet, but it might work out.

 

[JoeWPgh]

The easyist thing to do might be an 1/8" overlay on the baffle with the correct hole size cut into it. It should provide the clearance you need without altering the cab's internal volume that much.

 

[gregmari]

I think I can get them to fit easy enough with some of the techniques recommended but now I'm more concerned with the cabinets not being adequate. I don't want to ruin the drivers. Can anyone help me with the math? Here is the hartke cab specs. The EVM 15B speaker info is Link Removed. Any other info needed? Thanks

 

[byacey]

Router will work until it bumps into the edges of the cabinet. The baffle is recessed over an inch...

A Bosch Colt router should get in there fine from what I can tell from the picture; it has a pretty small base. The port opening flanges may be in the way a little; this small area could be rasped by hand.

A straight cut bit with a top follower bearing 1/16" smaller in diameter than the blade diameter should do it. Cut the lower half inch of the opening thickness, followed by a bottom bearing flush cut bit to trim the remaining 3/8" thickness left at the top of the opening.

 

[Mike Arnopol]

I do this aqll of the time.You only need to remove 1/16th of an inch, right? (1/8" total). Don't use a rotary rasp. They're better for more dramatic removal. If you're not experienced using one---it's going to bounce around like crazy.I'd use a rotary drum sander.
https://www.amazon.com/Sanding-Round-Sander-Sleeves-Woodworking/dp/B01FOQJLEA?ref_=fsclp_pl_dp_12

Slower but more controlled removal.I use the rotary rasp for more aggressive removal.

 

[seamonkey]

Or the most destructive in the wrong hands.

Or the most constructive in the right hands.
Make a template out of MDF. Cut a circle in MDF and Check that the driver fits.
Cut it to size to fit inside the baffle edge.
The MDF can be made thicker than the lip of the baffle backset so the router base doesn't hit the lip.

Or the template can put temporarily put on top of the existing baffle as somebody already mentioned.
Test/prototype before you cut. Test if it's even worth it.

 

[Slevage]

Or the most constructive in the right hands.
Make a template out of MDF. Cut a circle in MDF and Check that the driver fits.
Cut it to size to fit inside the baffle edge.
The MDF can be made thicker than the lip of the baffle backset so the router base doesn't hit the lip.

Or the template can put temporarily put on top of the existing baffle as somebody already mentioned.
Test/prototype before you cut. Test if it's even worth it.

I learned many years ago when auditioning drummers that a lot of people own drum sets.

I wonder if the same is true with routers?

 

[DJ Bebop]

I still say drum sander bit in a drill, a few passes around the hole will do it in about the same time it takes to read this.
No jigs, no routers, no saws, no files. Just around and around the inside edge of the hole.

I just did this for a Black Widow 18 in. speaker.

Had a cab spec'd and build for it, though the hole was off by a 1/8 of an inch. Took a drill with a drum sander bit, round and round in the hole and chamfered or rounded the edge as agedhorse said. Done in about 5-10 minutes. Really.