Suggestions Wanted: 12" Sub driver replacement

The stock amp is going to be tailored to the driver and cabinet design. The best would be to get another driver from Velodyne, however if you can use an exacto-knife, you could replace the surround.

I would order one for the active driver and one for the 15" passive and do them both at the same time. You will be good for another decade + for about $ 60 and your time.

See here

Parts express has a picture tutorial and a write up on how to accomplish this, it's fairly straight forward.

You *may* get a tiny bit better performance from swapping the driver, but you are still tied to the same box, therefore there is a cap on performance. Without knowing what the stock driver is tuned to, and the parameters, you could downgrade performance by swapping another 'better' driver into the box.

I know it sounds counter intuitive ( how can a better driver be worse? ) but the stock driver is likely a bit more efficient ( needing less amplifier power ) and it's designed for the application.

If you aren't at all happy with the performace, might I suggest fixing the surrounds if the rest is OK, and selling the unit, taking that money and getting something with better performance?

WinISD and Unibox wil model PR's but you need to know all the specs, the compliance of the suspension, moving mass, diameter etc. Likely you won't get that information from the manufactuer.

well, like mr. hurd said, all you would need to know is:

1. the output voltage across the frequency range for the amplifier (in other words, what internal eq does it have?)
2. the net internal volume of the enclosure
3. the subset of thiele small parameters as they pertain to the passive radiator
4. the cutout diameter for the driver (not all 12" drivers are exactly the same size)

#1 and #3 will likely be more hassle than you want to get into to and even if by some miracle you figure them out, then you will need another miracle to find a high performance 12" driver that matches up well. this is why the suggestion was made that it would be easier to fix your surrounds, sell your sub, and buy/build a whole new one. maybe hard to believe if it was said by just one person, but now there are two people suggesting the same thing.

then get a shiva, but when you blow out your passive radiator, don't say we didn't warn you.

if it randomly works, fine. if not, you will have a decent driver for your build.

The passive radiator would have to be tuned very high, because if it had any appreciable mass, it would sag. Dremel to enlarge a hole 1/8" .... I would say probably not a good idea.

Jigsaw might be your best bet, but you would need to tape the cabinet so the shoe doesn't dig in with masking tape, this also gives you a good opportunity to mark on the masking tape.

Beware that a 'frankencabinet' would also ruin it's resale value though.

Michael,

I put 2 of the epic 12's in a box that was 2.6 cf. It was not good for any HT in my opinion. It sounded extremely bright- not deep at all. As a matter of fact, not even low at all. I am going to build a nicer ported box and see what happens. We will see.

Thanks,

Robert

this thread has tremendous humor potential.

all i needed was a surround.

so here is what i did. i bought a shiva, but it didn't fit in my box, so i spent a week with a dremel tool carving out a marginally larger hole, of course it isn't exactly round, so my driver now appears to have frankenstein-like scars around it, but that doesn't matter so much because when i fired up wotw pods emerge i heard a giant fart sound and realized that i had just blown my passive radiator out of my box, so i ordered up a larger passive radiator, which didn't fit in the old hole either, so no problem back to the dremel, another week later i have the hole cut and passive radiator installed, but with all the weight to tune the cabinet properly the passive hangs down below the sub like an old pair of sheep balls, so now i have the box sitting on its side, but that doesn't look so good with the feet sticking out sideways, so i took off the feet and filled in the holes primed and painted them, but the paint doesn't really match so more frankenstein's monster, now i mounted the feet on what is now the bottom of the enclosure, but i stripped one of the feet when i was installing it, so every time i hit a big bass note my subwoofer falls over, but you know what, i have great bass and that is all that matters. :-)

My Velodyne VA1512 had the same "foam rot" on its 12" driver which you described. I purchased a re-foaming kit from Speakerworks.com and did the repair myself. The kit costs $11.50 and includes all materials to do the repair.

http://www.speakerworks.com/12F_inch...t_p/swk12f.htm

The repair job was fairly easy (the hardest part was cleaning off all the old foam the most of the old glue residue). I didn't even have to remove the dust cap from the driver.

The woofer is now as good as new and my trusty old Velodyne is working perfectly.

Distortion/Bottoming out = overdriven. Any driver or amp can be overdriven. The trick is to get a little more than you need, because even if your sub is never overdriven, but frequently used close to its maximum capacity, you can expect early failure of the driver or the amp.

Correct me if I am wrong guys, but I think the rule of thumb is to try not to exceed 80% routinely in your settings, to avoid shortening the life expectancy of the equipment.



Mink oil can be applied to the foam surrounds periodically to keep them supple and pliable. I have read that Bob Carver recommended it for use on his Sunfire subs.

The foam surrounds will dry out and crack with time. Heat can accelerate the drying process.

Mink oil is the main ingrediant in most leather care products, such as those meant for use on leather shoes or leather furniture or leather coats. It is also used on baseball gloves to keep the leather flexible and prevent cracking.

I find the pre-moistened leather care wipes to be particularly convenient for this purpose, such as the ones made by Maquire's for use on vehicle leather seats.

I have even used Lemon Pledge wipes on foam surrounds, because the package said they were, "Great for use on leather," and the main ingrediant listed was a mink oil.

I'm glad you were able to revive your sub in a reasonable and practical way, but perhaps it is better suited for another room, since it seems to be getting pushed a little harder than it should (bottoming out/distortion).

Maybe now is a good time to begin looking at different DIY sub projects, and with all the money you saved by following Michael Hurd's advice on replacing your foam surrounds, you're already part-way there in affording a new build.