dual voice coil sub questions and ohm questions

[black cali v6]

can you wire each coil to a seperate channel on the amp or will they play out of phase and not sound right?

also is there an advantage to running subs at higher impedence? i know most amps that can do it put out more power at 2 ohms or 1 ohm, so if you would wire your subs this way, why wouldnt u? do you get better sound quality at 4 or 2 ohms?

thanks

Zack

[MTMike]

I don't exactly know the answer to the first one, but to me it doesn't sound like a good idea to do that.

As for impedance, think in Ohms Law: P=VI and I=V/R Where P=Power V= Voltage I=Current and R= Resistance or Impedance. Using algebra, if R(impedance) goes down by half, I (current) doubles, and therefore power doubles. so if you run a sub with twice the impedance as another, the one w/ more impedance will put out half the power. So genreally, lower impedence results in more power, so long as the amp can handle it

Hope I didn't confuse you too bad [img]smile.gif[/img]

-Mike

[96firebird311]

<blockquote>quote:</font><hr>Originally posted by MTMike:
As for impedance, think in Ohms Law: P=VI and I=V/R Where P=Power V= Voltage I=Current and R= Resistance or Impedance. Using algebra, if R(impedance) goes down by half, I (current) doubles, and therefore power doubles. so if you run a sub with twice the impedance as another, the one w/ more impedance will put out half the power. So genreally, lower impedence results in more power, so long as the amp can handle it<hr></blockquote>
You are correct Mike. If your amp can handle it... go for it!! As far as wiring a DVC to 2 seperate channels I would advise against it. You should bridge the 2 channels together and send your sub a mono signal. Keep in mind, not a lot of amps are stable down to 1 and 2 ohms MONO. But if yours is, it's the best way to go. What amp is it anyway?

[EyeOutThere]

DVC subs were originally designed to run off 2 channels or 2 entirely separate amps. Running the sub off 2 channels is NOT a problum at all, as long as you are sending it a Mono signal.

If you have two 4ohm voice coils, your best bet is to wire them in parallel for a 2ohm load and bridge your amp. However, many amps are not stable at 2ohms when bridged. If that is the case, your best bet is to run one coil off each channel of your amp.

What is the impedance of each of your voice coils? What kind of amp do you have and how low of an impedance will it take on each channel? …when bridged? Is there a switch on the amp to put it on “mono”?

[Brian Dieckman]

<blockquote>quote:</font><hr>Originally posted by EyeOutThere:
DVC subs were originally designed to run off 2 channels or 2 entirely separate amps. Running the sub off 2 channels is NOT a problum at all, as long as you are sending it a Mono signal...<hr></blockquote>

Yeah, what he said... If the speaker manufacturers simply wanted you to connect the coils together to lower the impedance, then they should be producing the speakers in THAT resistance. Anyway, I think the real reason they started that was because people wanted more flexibility in how they hooked up their systems.

You can use a simple Y adapter to split a mono signal to two seperate amps (then back to two channels at the amp) If you're starting with a stereo feed, you'll need to combine them into one, then back into two at the amps. The goal is to get the same signal to all inputs of all amps involved.

HOWEVER: If you're going to be running one amp to one dual voice coil woofer, then it makes sense to bridge the coils and the amp to get more power. (if your amp and speaker can handle it)

Back in my day of installing stereos, people would come in and demand dual VC speakers then only use one amp. Well, that's okay, but the two-ohm speakers are cheaper than the dual four-ohm speakers, and you're getting the same results. Whatever.

Here's what I would do: First off, see if the amp is bridgeable. If it is, find out the minimum resistance load it can handle (ohms) If the amp can handle the value that results from wiring the subs coils in parallel, then that's your best option. For instance, say your amp can handle a two-ohm load when bridged. Say your sub has dual four-ohm coils. Wiring the coils in parallel will give you a two-ohm load. PERFECT.

The problem I run into sometimes is that when you bridge an amplifier, it's load rating doesn't neccesarily drop. For instance, the old rockford amps could be bridged, but their minimum load rating was four-ohms. In this case you'll be risking the amps integrity by giving it a two-ohm load.

So in short, check your amps ratings and your speakers specifications. If you still have questions, post that info here and we can help.

-Brian

[black cali v6]

i havent bought my amp yet, thats why i was asking. also asking because i might get either a jl stealthbox with a 10w3d4(dual 4 ohm voice coil) sub already in it.

i just want to run 1 sub amp, and i was looking at:

JBL BP600.1 mono amp.....300 watts RMS X 1 @ 2 ohms i think

AUDIOBAHN A-2801Q 2 channel.....280 watts RMS X 2 @ 4 ohms mono..not sure if its stable to 2 ohms bridged

AUDIOBAHN A-1801X 2 channel.....400 watts RMS X 1 @ 2 ohms mono

JL 250/1 mono amp....250 W RMS @ 1.5 ohm-4 ohm (11V-14.5V) {i guess it outputs the same power with variable impedence)

any suggestions, the bp600.1 seems like the best value

thanks

ps: im going to make a more comprehensive separate post about the system im thinking of putting together, please post there too if you have any suggestions!

zack

[96firebird311]

<blockquote>quote:</font><hr>Originally posted by EyeOutThere:
DVC subs were originally designed to run off 2 channels or 2 entirely separate amps<hr></blockquote>
Negative.
<blockquote>quote:</font><hr> Anyway, I think the real reason they started that was because people wanted more flexibility in how they hooked up their systems <hr></blockquote>
This is correct. Think about it, if you have 2 woofers your wiring options are more flexible. Now think about if you have 4 or even 6 or 8 woofers for that matter. Now you have some serious options available. DO NOT try to run one DVC sub off two amps! It is possible and I have seen it done but by pros only. WHY? Because you have to put the exact same amount of power to both coils AND they have to be crossed over at the exact same frequency. This would require, at minimum, an oscilloscope. This is not for beginners!! But it is possible. [img]smile.gif[/img]

[EyeOutThere]

The very first DVC sub (I belive it was a Pioneer) was designed to run off two low power channels. They even claimed you could run them right off of your headunit (If it had a crossover in it). Naturally, they realized all the great things a DVC sub had to offer in terms of wiring flexibility. Today’s DVC subs are manufactures and sold mainly for their wiring flexibility. However, the architecture of the DVC sub has not change and they still can and often are run off of two channels (so long as they are being sent the same signal). Like I said, running the sub off 2 channels is not a problum, but your right, running one off 2 amps can be tricky.

[black cali v6]

few more questions:

is $300 shipped for a stealthbox with a 10W6 in it a good deal?

with the coils wired in parallel(3 ohm load), how much power will a JBL BP600.1 provide the sub?

is this too much for the sub? (handles about 300 RMS)

thanks

[EyeOutThere]

<blockquote>quote:</font><hr>Originally posted by black cali v6:
few more questions:

is $300 shipped for a stealthbox with a 10W6 in it a good deal?

with the coils wired in parallel(3 ohm load), how much power will a JBL BP600.1 provide the sub?...<hr></blockquote>

That would be a 2ohm load. That amp would put out 300wtts. Your sub should be fine. Just don't play the sub to the point of distortion.

[black cali v6]

no its a 3 ohm load......its a JL 10W6D6.....which has two six ohm voice coils.....wired in parallel thats 3 ohms....1/6 + 1/6 = 2/6 = 1/3 = 3 ohms

i think anyway

good price tho?

have to decide whether or not im getting it soon


zack

[96firebird311]

<blockquote>quote:</font><hr>Originally posted by black cali v6:
no its a 3 ohm load......its a JL 10W6D6.....which has two six ohm voice coils.....wired in parallel thats 3 ohms<hr></blockquote>
That is correct. The JLW6 has dual 6 ohm coils, so in parallel it is 3 ohms. It makes them the perfect sub for a trio!

[EyeOutThere]

Roger that. I thought you were going with the 10w3d4. My bad ;)

[black cali v6]

no worries, my only problem is the amp

this same question is in another post btw....

amp im getting is a JBL BP600.1 which makes 300 watts RMS @ 4 ohms and 600 watts RMS at 2 ohms.....does this mean it makes about 450 RMS @ 3 ohms?

if so, the sub only takes about 300 watts RMS...should i either get a JBL BP300.1.....or turn the gain down on the 600.1?

[96firebird311]

Yes, the JBL 600.1 will output about 450watts RMS at 3 ohms. The sub should be safe with the power. You shouldn't have anything to worry about.