Driving dual voice coil sub with two independent stereo channels

[frikk 10+ year member]

Hello everyone.

I have a dual voice coil Natural Sound subwoofer from Audiobahn.

http://www.crutchfield.com/S-km96OzBbiAB/cgi-bin/ProdView.asp?g=520&tab=essential_info&i=037AW1251S#Tab

My amp:

http://www.mtx.com/caraudio/archive/pro300x2.cfm

I am thinking about driving each voice coil from a different channel on my amp. Each channel can output 150 watts @ 4 ohms, and each voice coil is 200 watts RMS @ 4 ohms.

My amp does not have a mono switch. So I have three questions:

1. Running it in stereo (Left to the Voice Coil 1, Right to Voice Coil 2) is a bad idea, correct? This would probably damage my sub since the signals would be out of phase (and possibly completely different)

2. Is the solution of simply making a Y adapter into the RCA input of my amp (so both inputs are right or left) a good solution? Is there any other solutions, or should I simply forget about the idea and put both coils on the same channel?

3. Is this solution (each coil to a different channel) better / worse than hooking it up to one channel? (See Below)

If I hook up the coils to a single channel in parallel, I would have a 2 ohm load @ 300 watts RMS. If I were to put each coil to a separate channel, I'd have two 4 ohm loads @ 150 Watts Each. Either way I have about 300 watts going to the entire sub. Does it matter which set up I choose? Other than the fact that in one setup I have an empty channel (unused), and the other channel I am in mono (I'll be mono anyway since I'm only using one sub...). Is there some kind of sound quality or power issue, or something else I'm missing?

Thanks,

Blaine

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[dipitydoo 10+ year member]

With the vast majority of recordings, bass is not recorded in stereo, so running each coil in stereo will generally not be a problem. That being said, your amp is indeed bridgeable. Wire your coils in series, and bridge to amp. By the way, that amp will do somewhere around 250w per channel at 4 ohm.

 

[frikk 10+ year member]

With the vast majority of recordings, bass is not recorded in stereo, so running each coil in stereo will generally not be a problem. That being said, your amp is indeed bridgeable. Wire your coils in series, and bridge to amp. By the way, that amp will do somewhere around 250w per channel at 4 ohm.

Hey man thanks for the response.

First - the paper I got from the factory said it tested around 175w RMS per channel. at 4 ohms (rated at 150). It also said it pushed 346w RMS @ 2 ohms (rated at 300).

Second - If I put them in series and bridge them, that'll put the omage at 8ohms. I don't know what the amp does at 8 ohms - it only says that it puts out 600RMS @ 4ohms. I'd guess it only put out like.. 300 watts RMS probably. Wouldn't that be just the same as hooking the woofers up to a single channel @ 2 ohms and 300 watts?

I guess I don't see the advantage to bridging the two coiles in series. I could definiately just try everything out myself and see how it sounds. I don't have it the box made or my amp hooked up, yet.

 

[djeazie 10+ year member]

give you RCAs a mono signal. Take your right RCA wire buy a Y adapter and plug it into you amp. Each input will be getting the same signal.

 

[dipitydoo 10+ year member]

8 ohm mono power equals combined output of both channels in stereo at 4ohm. Which in your case, would be 350w.

 

[n2audio 5,000+ posts]

and bridging eliminates any stereo seperation there "may" be between channels. IMO it's slightly preferred over coils run in stereo.

 

[neonrt 10+ year member]

and bridging eliminates any stereo seperation there "may" be between channels. IMO it's slightly preferred over coils run in stereo.

my thoughts exactly.

 

[Earthman 10+ year member]

Hello everyone.
I have a dual voice coil Natural Sound subwoofer from Audiobahn.

http://www.crutchfield.com/S-km96OzBbiAB/cgi-bin/ProdView.asp?g=520&tab=essential_info&i=037AW1251S#Tab

My amp:

http://www.mtx.com/caraudio/archive/pro300x2.cfm

I am thinking about driving each voice coil from a different channel on my amp. Each channel can output 150 watts @ 4 ohms, and each voice coil is 200 watts RMS @ 4 ohms.

My amp does not have a mono switch. So I have three questions:

1. Running it in stereo (Left to the Voice Coil 1, Right to Voice Coil 2) is a bad idea, correct? This would probably damage my sub since the signals would be out of phase (and possibly completely different)

2. Is the solution of simply making a Y adapter into the RCA input of my amp (so both inputs are right or left) a good solution? Is there any other solutions, or should I simply forget about the idea and put both coils on the same channel?

3. Is this solution (each coil to a different channel) better / worse than hooking it up to one channel? (See Below)

If I hook up the coils to a single channel in parallel, I would have a 2 ohm load @ 300 watts RMS. If I were to put each coil to a separate channel, I'd have two 4 ohm loads @ 150 Watts Each. Either way I have about 300 watts going to the entire sub. Does it matter which set up I choose? Other than the fact that in one setup I have an empty channel (unused), and the other channel I am in mono (I'll be mono anyway since I'm only using one sub...). Is there some kind of sound quality or power issue, or something else I'm missing?

Thanks,

Blaine

Your setup is not ideal. I suggest a different amp for that speaker or a different speaker for that amp

 

[frikk 10+ year member]

Your setup is not ideal. I suggest a different amp for that speaker or a different speaker for that amp

Earthman - what don't you like about the setup? I am matching 350 watts RMS to a 400 watt RMS speaker. Do you mean that it is too "underpowered"? I always thought that I'd want to underpower a speaker, not overpower it and risk blowing it.

 

[Earthman 10+ year member]

Earthman - what don't you like about the setup? I am matching 350 watts RMS to a 400 watt RMS speaker. Do you mean that it is too "underpowered"? I always thought that I'd want to underpower a speaker, not overpower it and risk blowing it.

Nothing to do with the equipment you have,it's simply the nominal impedance of the sub is not a proper match for that particular amp or vise versa

 

[Earthman 10+ year member]

The specs for that amp state:4ohm stereo,2ohm stereo,4ohm bridged.Well that sub has dual 4ohm coils.Which tells me you can't bridge the amp at 2ohm because it's not stable.You will not pull the full 600 watts from the amp with this sub.300 is the most you will pull safely.You would risk blowing the amp if you have it running a 2ohm bridged load.I suggest one more of those subs,than you will be within the parameters of the amp.Otherwise you have to wire your one sub in series and run an 8ohm bridged load or wire it in parallel and hook it to one channel of the amp.Hope this helps you

 

[frikk 10+ year member]

The specs for that amp state:4ohm stereo,2ohm stereo,4ohm bridged.Well that sub has dual 4ohm coils.Which tells me you can't bridge the amp at 2ohm because it's not stable.You will not pull the full 600 watts from the amp with this sub.300 is the most you will pull safely.You would risk blowing the amp if you have it running a 2ohm bridged load.I suggest one more of those subs,than you will be within the parameters of the amp.Otherwise you have to wire your one sub in series and run an 8ohm bridged load or wire it in parallel and hook it to one channel of the amp.Hope this helps you

Ahh, I see what you're saying. Yes - you're right. I do not plan on bridging the amp. I will probably just parallel it and run it to one channel.

Thanks for the help,

Blaine

 

[dipitydoo 10+ year member]

There is nothing wrong with your setup. You have a sub with dual 4 ohm coils, rated at 400w total power. You have an amp that is capable of 350w at 4 ohm stereo/8 ohm mono, and 600 - 700 watts at 2 ohm stereo and 4 ohm mono. That mean with one sub, you will get 350w, which is fine for that sub. Whether you wire each coil in stereo or bridge the amp and wire the two coils in series (8ohm), you are still getting the same amount of power to the sub (350). The only thing is that in this configuration, the amp will not put out its maximum capable power at that load. This however, is not a problem, since the sub is only rated at 400w, and it may not like the 600 - 700w the amp is capable of. While it may not make a difference whether you wire it in stereo or mono, I would still bridge the amp, just to be on the safe side. You can later add another sub to that amp if you wish, and wire it at 4 ohm mono.

 

[frikk 10+ year member]

Cool - thanks a lot for the help //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif

Don't you think I may blow the sub if I power it at 600-700 watts RMS?

 

[n2audio 5,000+ posts]

Cool - thanks a lot for the help //content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif
Don't you think I may blow the sub if I power it at 600-700 watts RMS?

You could - if you didn't adjust the gain appropriately and/or use some common sense with the volume knob.

But why does it matter? You can't wire that sub to that amp in a way to get the 600-700w from it.

You're what-ifing yourself to death. And earthman needlessly drug it out another 5 posts. Just hook it up in series for 8 ohms with the amp bridged -- you're good to go.