# DVC - Pros and cons of parallel vs serial?



## snaimpally (Mar 5, 2008)

I recently got a Kicker 8" sub with dual 4 ohm voice coils. It will be powered by a Cadence A7hc amp which is stable even with a 1 ohm load. This is my first DVC sub and I have no clue what I should do.

Parallel wiring will create a 2 ohm load while series will create an 8 ohm load. The amp will output more power for 2 ohms than for 8 ohms. I am interested in SQ not SPL. Parallel will create the most SPL as the amp has more power due to the lower impedance. Will series be better for SQ? What other characteristics of the sub will be altered in parallel vs series? I'll probably try both ways just to hear it myself but I wanted to hear about any thing else I should consider in deciding how to wire them up.


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## mikey7182 (Jan 16, 2008)

snaimpally said:


> I recently got a Kicker 8" sub with dual 4 ohm voice coils. It will be powered by a Cadence A7hc amp which is stable even with a 1 ohm load. This is my first DVC sub and I have no clue what I should do.
> 
> Parallel wiring will create a 2 ohm load while series will create an 8 ohm load. The amp will output more power for 2 ohms than for 8 ohms. I am interested in SQ not SPL. Parallel will create the most SPL as the amp has more power due to the lower impedance. Will series be better for SQ? What other characteristics of the sub will be altered in parallel vs series? I'll probably try both ways just to hear it myself but I wanted to hear about any thing else I should consider in deciding how to wire them up.


Different wiring options don't affect SQ per say... simply how much the amp is going to put out. What you will want to be concerned with is the power output of the amp at 2 vs. 8 ohms, vs. the power handling of the sub. So if the sub can handle 400 watts RMS, and the amp puts out 250 watts at 4 ohms, and 500 watts at 2 ohms, you'll probably want to run it in parallel. If, on the other hand, you have an amp that will get you close to RMS at 8 ohms, chances are you'll be WAY overdriving it at 2 ohms unless you really keep the gains down. There are some who will argue that at 8 ohms, the amp will run cooler and with less distortion, resulting in greater SQ. However, most sub amps are designed to run at least down to 2 ohms mono with no problem.


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## St. Dark (Mar 19, 2008)

Series wiring between subs can have a detrimental effect on sound. No sub is perfectly damped- electricity generated by the first sub's overshoot or ringing (moving differently than the actual signal dictates) is fed to the next, and so on. With a dual coil sub, probably less of an issue. Even with multiple subs, is it audible? Depends on a lot of things- speaker, amp, ENCLOSURE - but thought I'd bring it up.
To the amp, as impedance decreases so does damping...take the load really low for that amp and the power supply starts to lose stability, feel the stress "that'll get some beads goin'"... in your case if the amp is truly built to run at 1ohm then using it at 2ohms should easily be fine. If you get enough power to satisfy your ears at 8ohms, then that's fine too!


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## phatredpt (Feb 22, 2006)

The one thing that will change is the Inductance, which may or may not result in a more pronounce impedence peak and resulting change in response at that point. Depends on the construction and design of the driver.
I actually posted this same question here:
http://www.diymobileaudio.com/forum/showthread.php?t=11957&highlight=inductance

Good reading... there were several points raised.
The inductance issue is on page 5
Hope this helps


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## snaimpally (Mar 5, 2008)

Thanks! I did search before posting and did find that thread but I only looked at the first page. I'll go back and read the entire thread.

One thing that does concern me is that the Cadence has power to spare compared to this 8" Kicker sub. The A7Hc is rated at 500 watts @ 4 ohms and 800 watts at 2 ohms. Each of the two voice coils can handle a max of 200 watts.

Running in series to create an 8 ohm load would bring the output of the Cadence down to a level that is closer to the capacity of the voice coils. On the other hand, I don't want to run the amp close to maxxed out. So I'm leaning toward running it in parallel with a 2 ohm load initially.



phatredpt said:


> The one thing that will change is the Inductance, which may or may not result in a more pronounce impedence peak and resulting change in response at that point. Depends on the construction and design of the driver.
> I actually posted this same question here:
> http://www.diymobileaudio.com/forum/showthread.php?t=11957&highlight=inductance
> 
> ...


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## mikey7182 (Jan 16, 2008)

As long as you set your gains appropriately, you could run a 1500 watt amp to that sub and be fine. Just be smart about it, and back off if the sub starts to sound overworked.


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## kappa546 (Apr 11, 2005)

snaimpally said:


> Running in series to create an 8 ohm load would bring the output of the Cadence down to a level that is closer to the capacity of the voice coils. *On the other hand, I don't want to run the amp close to maxxed out.* So I'm leaning toward running it in parallel with a 2 ohm load initially.


this makes no sense.


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## snaimpally (Mar 5, 2008)

kappa546 said:


> this makes no sense.


Well, probably not maxxed out but I'd rather have power to spare. I'm not planning to play at anything remotely resembling high SPLs.


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## kappa546 (Apr 11, 2005)

what i meant is your amp is no where near it's limits because it's hooked up to an 8ohm driver... think of it as headroom. i think you're better off wiring your sub in series


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## Mooble (Oct 21, 2007)

If you run the sub in 2 ohms, you can dramatically cut the gains on the amp which might eliminate some noise if you have a noisy car (electrically speaking). That would be a potential SQ benefit.

If you run it in 8 ohms, you get better SQ from higher damping ability, but you won't be able to cut the gains much which might mean increased noise.

If you have a quiet car, 8 ohms would probably be the better choice for you. If you have a noisy car or really cheap interconnects, then 2 ohms might be better.

I doubt that you'd be stressing the amp either way, but it should have longer life run at 8 ohms.


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## snaimpally (Mar 5, 2008)

Thanks! I don't think the car is very noisy electrically. Maybe I'll start off with series then.



Mooble said:


> If you run the sub in 2 ohms, you can dramatically cut the gains on the amp which might eliminate some noise if you have a noisy car (electrically speaking). That would be a potential SQ benefit.
> 
> If you run it in 8 ohms, you get better SQ from higher damping ability, but you won't be able to cut the gains much which might mean increased noise.
> 
> ...


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## Mooble (Oct 21, 2007)

snaimpally said:


> Thanks! I don't think the car is very noisy electrically. Maybe I'll start off with series then.


Actually, come to think of it, you won't really hear alternator whine through your sub anyway, so 8 ohms would be better.


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