Dual Voice Coil Subs? I need to learn!

[04Elantra]

I feel truly ignorant about amping subwoofers :( ...I search online and see so many schematics and diagrams my head is going to explode. My old systems just had powered tubes and that took all the guesswork out!

I need help in the two situations below:

What I want to figure out is if I have 2 amp channels (each putting out 110watts @ 4ohms) and I want to hook them each up to one coil of a DVC subwoofer (rated at 220 rms)...what does the ohm rating of the sub have to be to keep everything running properly with 4ohm amp output? (was that confusing....does that even make sense?!?)

Also, if I have one amp channel putting out 200 watts @ 4 ohms, can I power a DVC subwoofer (if so, what would its ohm rating have to be) or only a single coil sub?

THANKS FOR LOOKING (and thanks in advance for the millionth time to southpaw!) :bowdown: :bowdown: :bowdown: :bowdown:

[only1db]

okay....so you one sub or two???

if you have one sub...you will want to bridge the amp into mono...which means right negative and left positive....then on the DVC woofer...you will want (there will be two different posts on the subs...usually on different ends of the sub....it will look something like this


- + - +
| |_________________| |
| |
into the amp__| |
_____________________________|


does that make sense? your amp should say right on the amp how to make it mono...and there will be a switch on the amp to make it mono or stereo...making it mono and setting it up this way will garuntee that it will be a 4 ohm load....****....i have a 2ohm DVC....this still might work though. so when you add the two coils together it makes 4 ohms

[04Elantra]

that clears it up a little.....thanks

anyone else want to chime in?

[sed]

ok

http://www.rockfordfosgate.com/rftech/wiringwizard/2_4ohmDVC_4ohm.gif

is 4 ohms, that will be the most stable...

http://www.rockfordfosgate.com/rftech/wiringwizard/1_4ohmDVC_2ohm.gif

is one woofer, but its two ohms. You can wire it for 8 ohms, but it won't hit. With one woofer you are going to need a class d monoblock STABLE at 2 ohms.

You really don't want two amps pushing one sub at all

shawn :)

[only1db]

what a pita...i'm glad i got a 2ohm dvc....makes set up a little easier....good luck with everything!!

[04Elantra]

I actually was thinking of taking 2 old school ADS PH15s (6channel) and running them each at 3 channels bridged and using 4 channels for my speakers and the two leftover on one of the amps to power the subwoofer coils.

But now only1db said I should take the channels and bridge them into one and set it up for mono! If I have the amp already bridged to the lowest amount of channels possible (and it isnt specifically meant to power subs...prob wont have a mono switch)..then I can not use the ph15, right?.

Is it allright for two channels to power a sub? or should I just go back to the idea of using different amps (still a/d/s) to get the sub powered by one channel of a multichannel amp (such as running a 4 channel as 2 coax + 1 sub?

SORRY TO BE A STUPID PAIN..just want to get this system right...already started dynamating the whole car and plan to make an awesome SQ system.

[southpawboston]

you don't have the ideal setup for one sub. you can't bridge again two channels already bridged. you are stuck with having a minimum of three channels @ 150W each with the ph15. so if you have two of these amps, you are looking at six channels @ 150W, with no more room left to bridge. also if i am correct, the amp is not stable at two ohms in bridged mode, right? so you need five channels: so, two amps, which means that you could run four coak speakers @ 150W each (bridged), + two DVC subs through one 150W channel (breidge), and one bridged channel unused. you can not run one DVC sub off of the bridged channel, because the impedence would be 2 ohms, and the amp is not 2 ohm stable in bridged mode. the other problem with this setup is that one channel is not used, and the coaxes are getting more power than they need, relative to the two subs.

the amp is better configured running in 5-channel mode, to put 4 x 50W to the coaxes, and 1 x 150W at 4 ohms bridged to a mono-voice coil sub. i think that's more like what a/d/s had in mind with this amp.

oh, and if you're interested, i just picked up an old-school soundstream MC245, which is 4x35 + 1x100 at 4 ohms, with built-in active crossover. it is bridgeable to 2x90 @ 4 ohms + 1 X 100. but again, it's not designed for DVC subs, unless you hooked up two DVC subs @ 4 ohms to the 100W channel.

[04Elantra]

So it looks like I will be running SVC subs (definitely dont want to run 2 DVC subs on one channel with such little power)!!

Maybe I will get a second tiburon sub enclosure and mount it on the right side of the trunk and use the two channels from a ph-15 for two SVC 4 ohm subs...hmmm

BTW southpaw, do you really think the PH15 will put out 150 watts per channel in 3 channel mode..is the 110w rating truly that much underrated?

I might just get a pq20 and run it 80x2, 1x150 for the rear speakers and one svc sub..TOO MANY CHOICES

THANKS

OR MAYBE...I will just get the new Nakamichi PA-2004 to power all 4 speakers and the PA-4001 for a subwoofer. I can give my PQ10 to my brother's stereo project. :)

I dunno anymore! I gotta decide in the next few days so I have everything in hand before my week off from work (which is to be dedicated to finishing all audio installation). :cool:

[southpawboston]

sorry, i meant 110W bridged, not 150. but i bet it would do 150 when pushed!

[04Elantra]

Does that soundstream you have have to be run as a 3-channel?

[southpawboston]

it works as 5-channel (4x35 + 1x100), or 3-channel (2x90 + 1x100). it also runs as a strange 4-channel setup, with 2x35, 1x90, and 1x100 (for center channel setups). i think its rated for 4 ohms only, i don't think this model is 2-ohm stable.

[04Elantra]

PM me with what you would want for it....trying to decide how much power I want to have for the subwoofer (and thereby determining what sub I need to buy)

Also...these look like the older MC series...and are "USA made"...are they also of good quality?
http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&rd=1&item=7907162164&category=38638&sspagename=WDVW

[southpawboston]

they are newer than the MC series, newer than what i worked with, but they're probably still the good old soundstreams. i think before they were bought out they were still made in the US and considered "real". although i havne't worked with this amp in particular, my bet is that it's really good. they do look a lot like the older ones, i bet they are from the early to mid-90s.

[only1db]

depending on your set up...you could go with the eclipse pa4212....620 totall watts and 300 x 2 @ 2 ohm or 200 x 2 @ 4ohm...not ot metion they have awsome SQ....just a thought ....you can get them off ebay for like 200 or so...thats where i got mine!

[04Elantra]

I deciced to go with 1 SVC sub in a Tiburon Enclosure...just trying to decide which amp will "be enough" for me! Thinking about the Soundstream MC300 or MC500 (if I can find them) or just the ADS PQ20.

[only1db]

dont forget about sq ft....is it the right sq'd feet for you sub? i think that enclosure is only for that sub...and its a 10inch

[04Elantra]

can a 4ohm amp be used to drive 1 DVC sub that is rated at 8ohms?

[southpawboston]

yes, it will work.