Random probably stupid impedance question

[Eric B]

Woofers are two Alpine SWR-1222d's, series-paralleled to 2 ohms. They read about 2.1 on my POS meter. Box is all 3/4" MDF, divorced chamber, 1.3 cubes each with 4" PVC ports, one per chamber. Overall, box is 36x15.25x15.25? IIRC; I built it last year (it's either 15.25 or 16.) Each side has one pound of polyfill from me messing around with ideas for new box volume. IIRC gives it an effective volume of 1.8 per and tuning of 28Hz (without fill, 32 and change.) Doesn't act like its tuned that low though; there's a lot of rolloff down low. The system I heard was two AB 12's off an AB 1500rms amp in a Buick Century. That's all I know; a local shop demo'd it for me an a friend who was woofer shopping. It seemed to be tuned a little higher, but there was much less rolloff than my box.

Dude based off your box specs, its your box... you have a 1.3 cube chamber with only one port tuned to 28hz and only 1 4" port... design a new box thats has a lil more volume and take away the divider. make a 5 cube box tune it at 35hz and call it good.

[white4d96]

Thanks all for the advice.

I did build a new box, 4.3 cube at 35Hz but it needs to be 'glassed up and have some minor gaps filled (first time with a circ. saw=FALE.)

However I found another issue: there's a switch on my amp, next to the freq knob, that's recessed into the amp (you can only press it with a paperclip.) I was messing around with it when I had the heat sink off at some point and apparently left it pushed in. I pushed it again today so it popped back out and it seems to be putting out more clean power now. No idea what the hell this switch is or what it does; don't recall seeing any mention of it in the owner manual I found on PDF. Will be doing some more research to try and figure out what the heck it is.

[Boon]

Master/Slave?

[white4d96]

No clue. Didn't think these were strappable. There's no markings saying what it does. MTX site isn't working for me so I can't pull the manual up ATM.

[skittlesRgood]

you can only measure DC resistance with a DMM. impedance is the measure of AC "resistance". turning the amp on with the DMM connected and set to ohm is very bad for the meter. to measure impedance you need the DMM set to ac voltage and an ac clamp meter to measure amperage. voltage / amperage = impedance.

[Boon]

No clue. Didn't think these were strappable. There's no markings saying what it does. MTX site isn't working for me so I can't pull the manual up ATM.

May be a switch to allow the RCA inputs to be used with high level inputs... kinda like the kicker amps where you can feed the RCA inputs up to 14v or something crazy.