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2 subs, 2 monoblocks and 1 sealed enclosure. Should I divide the box?


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Hi all,

Thanks for taking the time to read my post. I'm currently in the process of putting a system together (my 1st proper one) and I'm just looking for some advice with setting up what I've acquired so far.

I have 2 sub set ups and I want to pick 1 to use (2x 12" Alpine Type R 4 ohm DVC 500wrms in a sealed dual enclosure and 1x 15" Memphis Mojo CM series 2 ohm DVC 1750wrms in a ported box tuned at 40hz) and 3 amps (2x Epsilon Alpha EA1000D class D monoblocks with approx 500wrms each 1 ohm stable and bridgeable and an Alpine MRP-F450 class AB 4 channel amp) and 2 Sony Xplode (I know, yuk!) 65wrms 6 1/2" co-axials.

I brought the monoblocks believing that they made 950wrms each @ 1 ohm, 700wrms @ 2 ohm and 450wrms @ 4 ohm, but the 2x 30A (60A) fuses in each make me think otherwise. I think they may have been tested at 16v, which makes those figures close to right without the efficiency correction (the amps aren't the most well known brand, though the 2006 (iirc) Australia's loudest car used the EA5000D monoblock amps with DD subs)

So I'm at a point where I don't think the Mojo will work with these amps, I was goin to strap them to it, but the subs impedance is no good (1 or 4 ohm), and like I said, I don't think these amps will have the grunt for the Mojo. Which brings me to my next plan...

Can I wire the Type R's to a amp each so I can run them at 1 ohm each? Will the subs sharing the same chamber/enclosure with seperate amps cause any issues (cancellation, out of phase)

And finally, can I run 2 amps semi-strapped? Wire them up to each other, but not join the outputs together? I was thinking of the ease of tuning them both if they were still being used in Master/Slave mode and maybe help eliminate any tuning issues between the 2 subs while they share a box. If not, would dividing the subs chamber into 2 seperate chambers be the go, or just get some proper/accurate tuning done?

This is by no means my finished system, as I intend to evolve it as knowledge, funds and equipment prices allow. Besides, I'm hanging out to see how that Mojo sounds.

Any help or advice will be hugely appreciated!

PS. I'm using 0awg OFC cable to a distro block to 4awg pos + and gnd - to the monoblocks and 8awg pos + and gnd - for the 4ch.

200A fuse on the 0awg exactly 18 inches from the battery and a 60A on each of the 4awg pos + cables (x2) and 50A on the 8awg pos + cable (x1). The big 3 with 4awg is my next mission. Does this sound about right?

Thanks everyone, sorry it's such a long post....

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I would run each type r off of 1 of the epsilon amps bridged and either save the memphis for something else or sell it. 2 12's have more cone area than a single 15 and running different subs in different sizes isn't advised, and use the alpine for the sonys. Just try and match each gain as close as possible.

edit

My friend whom im building a box for has 2 of the type r 12's in a prefab box running about 200 watts apiece(cheap lanzar pos) and they get loud as hell in his explorer. only other car to do that was a honda crx with 3 15's so theyll definitley do that on 500 or more.

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edit

My friend whom im building a box for has 2 of the type r 12's in a prefab box running about 200 watts apiece(cheap lanzar pos) and they get loud as hell in his explorer. only other car to do that was a honda crx with 3 15's so theyll definitley do that on 500 or more.

Lmao

Vehicle: 2014 GMC Sierra 2500HD WT

Head Unit: Pioneer DEH-

Mids/Highs: Focal Integration ISC 165’s (front) 

Subs/Amps: TBD

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OP, not sure about master/slave mode as I have never used it. But I do know tht if u run one sub off one amp it will have to be at 2 ohms since ur subs are D4. That's prolly 200-300 watts in total before box rise and efficiency is taken into effect. Although ur wiring is solid for the power u have lol!

Vehicle: 2014 GMC Sierra 2500HD WT

Head Unit: Pioneer DEH-

Mids/Highs: Focal Integration ISC 165’s (front) 

Subs/Amps: TBD

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edit

My friend whom im building a box for has 2 of the type r 12's in a prefab box running about 200 watts apiece(cheap lanzar pos) and they get loud as hell in his explorer. only other car to do that was a honda crx with 3 15's so theyll definitley do that on 500 or more.

Lmao

meant to put that it hurt my ears. chillmasterwills setup didnt do that at nopi(ofcourse the back was open).

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Of course I don't want to run two different sizes/types of subs, I was asking which of the 2 would be most suitable for the equipment I have so far.

Anyway, can the Type R's be wired together for a 2 ohm final load at the amp. If so, I'd just strap the amps I guess.

Funnily enough, I had the Alpine 4 ch powering the Type R's (to some sort of degree). I personally wasn't impressed with the 200wrms output they each had. Could definantly hear the bass from some distance, but they just sound like they were lacking and wanting more juice (which was impossible without clipping) and my (JVC) head unit and (Blaupunkt) factory speakers (components in front doors, co-axial in rear doors) were easily overpowering them, so this was plan B!

BTW, the car I'm installing this in is just my daily driver, a 2000 Vectra Estate (wagon). So space isn't really an issue.

And I was aiming for overkill on the wiring in case of any future changes and so I knew my power cables aren't a issue....

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And I don't think cone area makes a difference in this case, the Mojo can handle almost double the power than both Type R's combined, and the build quality appears to be a lot more solid than the Alpines. The Alpines are a nice affordable sub, where as the Mojo is for getting serious SPL. I'm sure there are plenty of instances where the cone area theory is true, but I don't think it's something that can be said as a blanket statement about all subs!

If I had the power to run it, I'd take the Mojo hands down. Might just pack that bad boy away till I find a bigger amp, I have a 91 Toyota Soarer and a 90 Honda Civic hatchback to install some gear into as well...

Thanks for the info, please keep it coming.

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edit posted as i was typing. If your set on the memphis than I would sell the monoblocks and get something that does rated. And power handling doesnt really mean much since thats exactly what it is, how much it can handle, if you put it in the right box it could only need 500w to get loud. I prefer boxes that are tuned to around 30hz but thats cause I listen to alot of C&S music.

Nother edit.

The type rs ive messed with seem pretty well built. only Memphis sub ive used was an older HPO 12. build quality was amazing on that thing but Ive never used there newer products. And the cone area thing does work. dont rememver the exact math but you take the cone area and multiply it buy the xmax to figure outthe displacement. Im a 15 man myself but the 12s have more cone area and good xmax. no idea on the memphis, the dont give the TS specs on their site.

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All good, going around in circles now...

What I want to now know is if only wiring a single coil of a DVC sub will be fine, I thought the extra voice coil was just for wiring simplicity? If so, then I can run the 2 Alpine subs to both monoblocks strapped.

If I do wire them like that, should I do anything to the disabled coil on each sub, short the coil out I guess you'd call it? I think I've read that the 2nd coil can interfere with the powered coil if it's just left open?

Oh and EP95, I was led to believe that your amps output should be about 75% to 150% of the subs nominal rms rating. So that would put 500w at about 35-40% of the Mojos rating, and you say this is fine? I find that really hard to believe....

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Only wiring one VC will half your subs rms rating. Its still safe but kind of useless unless you have to. And like I said, if its in the right box it could get loud off of only 500 watts. freeair your sub off of the full 1750 and see if it doesnt start to over excurt. The rating is its thermal capacity, not its physical.

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