BillFitzmaurice.info

I'll just pre-drill and add the lock washers onto the screws before I drive them in.

I don't have a multimeter. How much do I need to spend on one? I won't use it a lot, and I don't really feel like buying a $60 meter just for this build. Any suggestions?

What would you recommend for securing the access panel?

Thanks for all your help Grant.

Grant Bunter wrote:

I'll just pre-drill and add the lock washers onto the screws before I drive them in.

No need to do that with Recex screws, they are self tapping and drilling.
Put the driver in place, mark the screws points, then remove the driver (just in case you slip and put a screw through the driver). Insert the screws. Back them out again, and store until later, with the driver.

I don't have a multimeter. How much do I need to spend on one? I won't use it a lot, and I don't really feel like buying a $60 meter just for this build. Any suggestions?

You don't need a super expensive one. You want one that can measure AC voltage on a scale up to 200 volts, and a continuity tester on the meter is very handy, for way more things than building speaker cabs. If you make sure it also measures DC voltage, that can be handy for checking your vehicle battery if it has problems, or other vehicle testing. $20-30 should be fine.

What would you recommend for securing the access panel?

I used 12G screws I think. Overdrill the actual access panel, so the screw threads just slips through. Don't pre drill the flanges, just drive the screw threads into them. This will pull the access panel tight to the flanges.

Thanks for all your help Grant.

No worries at all, glad to be able to help...

Grant Bunter wrote:
Yep

Rowan611 wrote:Ok. I couldn't sleep last night, so I basically went over the steps in building this beast in my head. I came up with a few more questions.

1) My HT is an open basement. I'm running my HT along the longest wall. My current subs are on opposite walls almost midway, both behind the MLP. My plan was to stick the THT where my 20-39+ is currently (along the left wall, to the left of the MLP and within 5'). That's where I get the best bass response. Considering the space I'm trying to pressurize is almost 4500 cu ft, will one THT suffice. Right now I get no pressure, I can rattle doors and vents, I get some couch shake, but no feeling like I'm being punched in the chest (which is my main goal).

Start with one. If it's not enough, build another. The same can be said if you experience room modes/nodes creating a null.
Punch in the chest requires 50-70Hz at over 110dB for music. That's well above reference level which is 80dB + 20dB headroom.


2) How do you recommend cutting the panels? Meaning, should I cut a huge section exactly 23.5' tall, then cut the individual panels from these? I ask because one of my many concerns is making sure every panel is the same height. I haven't checked out cut list yet, and I will be. Maybe that will help me see this better.

Lay out all the required panels using cutlist.
http://delphiforfun.org/programs/cutlist.htm
You may need to lay out more than 1 sheet to get enough panels. Set your sheet size in inches. Sometimes you will need to manually solve.
Slip the owner of the programme a donation

3) Just to make sure I understand both Grant and Bill. You guys are telling me to directly screw the driver in place. Forgo the T-nuts or hurricane nuts completely. Same with the panel. Use 12G screws to secure it. I just want to verify for my own mind that I understand.

Yes, use recex screws to screw the driver in place, and 12G screws with the access panel. If 12G looks to large, look at 10G screws.

4) When Bill says to fill screw holes with adhesive I assume he's talking about the PL. Is that a safe assumption?

Yes. It is essential the cab be leakproof. You can also use bondo/auto body filler to cover up screws if left in place (unless you want stain/lacquer finish).

5) One of my biggest concerns is cutting the opening for the driver. I was planning on using my jig saw using a jig I found on youtube. However, I am wondering if I would be better off buying a router. Any thoughts on this?

A router (with a jasper circle jig) will certainly make cutting a driver hole and rounding cab edges much easier. If you're on a budget, forget the router. I have cut plenty of baffle holes with a jigsaw freehand. Just practice some. And you can use a sander to round off cab edges, though this takes a lot longer.

6) Finally, I thought I would use some speaker gasket around the driver and access panel, just as a precaution. Will that make driving the screws more difficult?

The driver should have an adequate gasket already. I use closed cell foam strips for my access panels, but speaker gasket will be fine if it's wide enough. Some sealing method for the access panel is mandatory.

I just built two right angle jigs and Ive found a good 2x4 to use for another assembly jig; although having just read through that section again Bill does recommend plywood. So, I'll cut another piece for that. It's slow going now, but once my CSM approves the driver and amp purchase, I can start.

Thanks again for all the help.

67baja wrote:The USA400 amp is a good amp, and has no fan so it is silent. I run 2 Otop12s on one channel of my USA400. I don't have any experience wit the other amp. Almost ANY amp will drive a THT to stoopid loud in a house. The Yung plate amps are good bangs for the buck as well.

Rowan611 wrote:Well I can't use CutList since Mac's aren't supported. I will just figure it out on the actual 4x8s

Stratispho wrote:

Rowan611 wrote:Well I can't use CutList since Mac's aren't supported. I will just figure it out on the actual 4x8s

There's a Sketchup Cutlist plugin for Macs.
https://code.google.com/p/cutlist/wiki/Installation