Jack 12, first build, first test...

[Kirk Baptista]

Ok, so I got my first Jack 12 to the point where I can finally hear it.

I have it hooked up to my GK MB Fusion amp, (350W@8ohm) plug in the bass, and at low volume it is sweet. Pump up the jam, though and I get a pop when the driver extends fully. Hmmm.

Checked the back, to make sure nothing was touching it from the back. Next thing, could it be hitting the phase plug? Triple checked the plans, to make sure I didn't add an extra extension or something. I have three 1/2 extensions on the baffle, for 2" total, including the baffle. Also have the mounting ring on the baffle, so the depth should be 1" to the speaker.

My question is, could anything else be causing this? Out of phase? Air leaks? I don't think either one is a problem, but you never know. Anyone else have this happen?

The driver is new, and was broken in per the plans.

Sigh, back to the garage...

[Bill Fitzmaurice]

Pull the driver, see if there's any denting of the dustcap.

[Kirk Baptista]

Yep, there is. Somehow my phase plug is 3/16 over. Well, no harm done and easy enough to fix.

[Bill Fitzmaurice]

Yep, there is. Somehow my phase plug is 3/16 over. Well, no harm done and easy enough to fix.

If you have a good sized spade or forstner bit, say 1 1/2", use it to drill a 1/4" deep relieve into the plug to clear the tip of the dome. Or use a router.

[Kirk Baptista]

Ok, routed off 1/4", sanded down and repainted, now the plug is within 1 1/2" where it should be.

Evrything back together... no pop, just a lot of clean sound, and lots of things rattling off shelves. Very satisfying after six weeks of building. Blue tolex came out very nice. Now I just need to add the tweeter array, and it'll be ready for prime time.

Also working on some internal lighting, just for fun.

I'll post some pics as soon as it's done.

[Frankie G]

Awesome. Glad to hear that worked out for you quickly. Definately post some pics! I would like to check out your lighting idea!