Wiring Question.

[Rob221]

Need your help guys,as i am new to car audio.I have a x200.4 i am running a pair of 6.5's to the front 2 channels.I bought a set of RSDC102'S and was woundering what would be the best way to wire them to the rear channels.Diagram would be helpfull.Thanks

[stipud]

Wire the 10D2's in series (run a single wire from the - terminal on one side of the woofer, to the + on the other side, then use the remaining terminals as the + and - for your speaker wires. Then connect each subwoofer to an individual channel on the amp. Make sure your speaker box has a divider in it, and this will be the best possible setup.

[Rob221]

Thank you for your help.So you are saying wire it like this per sub?

[deathcloud]

Yes that is what he is saying.

But won't that only give each sub 200rms each? Is that enough? That is only 1/3 of the power they need.

[Rob221]

Yeah that was my next question.Is that enough?It is in a 350z.

[stipud]

Yes that is what he is saying.

But won't that only give each sub 200rms each? Is that enough? That is only 1/3 of the power they need.

Subwoofers never need their maximum thermal power rating, usually they can hit full excursion with much less. Just because he can power his sub with 600w doesn't mean he should. My single RSDC10 LOVES 250 watts and already plays 10dB higher than my front stage. So with 400w on twice as many subwoofers in a tiny Z car... that's going to be an extremely bloated bottom end!

The difference between 400 watts and 800 watts on his setup is only going to be 3dB at most (every time you double power you gain 3dB), so 400-1200 watts would only be 4.5dB. Not a big deal, especially considering the added power draw you would have by going up another 800 watts... new battery, alternator, power wiring, etc., and not to mention wasting the trunk room on a second amp. Total overkill if you ask me.

[Bfowler]

i was just playing with rsdc12 on 150watts. in a subaru forester

i think you will be pleasantly surprised on what they can do with little power.
i know i was!

they DO respond well to extra power, but realize that your are still putting 400watts of bass in a 350z. a little goes a long way

[deathcloud]

Ok cool. This makes sense. It should sound good with two 10s in there.

[audiophyle_247]

The difference between 400 watts and 800 watts on his setup is only going to be 3dB at most (every time you double power you gain 3dB), so 400-1200 watts would only be 4.5dB.

& to the human ear a change in 3db is the equivalent of twice the volume.
So that extra 4.5db is only a 150% increase in bass volume or so. (actually more since it is an exponential change, but the point has been made)



Personally, I would run the 1 sub bridged @ 4 ohm for the 400w rms and build a nice ported enclosure for it. Keep the second sub as a backup.
Double the power (+3bd), half the woofers (-3db), pretty much gets you the same output but you get the option of now using a ported box (+?db, determined by box design) without sacrificing your entire trunk space.

[deathcloud]

I was thinking about that too. Nicely put.

[stipud]

The difference between 400 watts and 800 watts on his setup is only going to be 3dB at most (every time you double power you gain 3dB), so 400-1200 watts would only be 4.5dB.

& to the human ear a change in 3db is the equivalent of twice the volume.
So that extra 4.5db is only a 150% increase in bass volume or so. (actually more since it is an exponential change, but the point has been made)



Personally, I would run the 1 sub bridged @ 4 ohm for the 400w rms and build a nice ported enclosure for it. Keep the second sub as a backup.
Double the power (+3bd), half the woofers (-3db), pretty much gets you the same output but you get the option of now using a ported box (+?db, determined by box design) without sacrificing your entire trunk space.

You've got that completely backwards. The human ear hears things on a logarithmic scale. You get twice as much sound output by doubling the power, but the amount the difference the human ear hears is much less than that. A difference if 3 decibels is negligible. 1dB is the smallest difference in volume that the human ear can differentiate. 3dB is about as much as clicking your volume dial up a notch or two. That's it.

Also your comparison with the ported box is false. You do not double the power by running 400w to two subs vs running 400w to one sub, the power is constant. So you only lose 3dB from removing the second woofer, and what you gain is only derived from your port. Assuming the port added anywhere near 3dB, it would only be around the tuning frequency of the port, whereas having the second woofer would extend the volume across the entire frequency band of the woofer. So in this case I would recommend running both subs for optimum sound quality and probably no difference in volume compared to a ported setup with a single woofer.

[Rob221]

That’s good to know. Really didn’t want to add another amp and such. I am putting the subs in a sealed box with separate chambers of .6 volume per chamber. Box is in front of the strut bar facing the back of the car.

[Bfowler]

that looks like it should do the biz quite nicely. i think you will be very happy!

[Eric D]

That box looks good so far. I personally would skip the push terminal though. Those tend to suck over time. They allow wire to corrode too much. You may be better off with a bigger binding post type, or just running the speaker wires all the way to the amp through a small hole in the box which you then fill with caulk. This is just my opinion though.

[Rob221]

Thanks i like the looks of the box.I here you Eric about the push terminals.Well if the give me a problem i will follow your suggestion and drill a hole and wire direct to sub.

[audiophyle_247]

I stand corrected on the sound perception, and tomorrow I will be confronting my Acoustics instructor about it. Very important issue in regard to auditorium design, which he is supposed to be teaching us. lol

Looking online for some cold hard facts to throw in your face, I have discovered that a 3db increase is percieved as a 25% increase in volume, a 6db increase = 50% louder, and 10db =100% increase.
Good to know.

Also your comparison with the ported box is false. You do not double the power by running 400w to two subs vs running 400w to one sub, the power is constant. So you only lose 3dB from removing the second woofer, and what you gain is only derived from your port. Assuming the port added anywhere near 3dB, it would only be around the tuning frequency of the port, whereas having the second woofer would extend the volume across the entire frequency band of the woofer. So in this case I would recommend running both subs for optimum sound quality and probably no difference in volume compared to a ported setup with a single woofer.

You are running 2 subs on 200w each, dropping 1 and bridging the amp lets you run 1 sub at 400w, which changes nothing. Output should be the same in either case. About the same thing as you just said.

There is not very much space in a 350z , and a sealed box housing two 10's cannot be built big enough to get a very smooth freq response, and a ported box would be almost out of the question.
Dropping to 1 sub literally doubles the amount of airspace you can give to the one sub, which would greatly flatten the freq response and noticeably increase the low end response. Running 2 subs in a borderline too small box will only reinforce the already poor freq response. This is the case for sealed boxes, I am not even talking about ported yet. So the 1 sub wont be any louder or quieter than the pair, but large change in box volume will positively impact sound quality & linearity of the bass response.

Now, ported enclosures. Drop the single sub into a ported box, and tune it very low (25~28hz) and you are not just "boosting" the bass at the tuned freq but instead extending the freq curve, making this 10" sound much more like a 12" or 15".
The ear's sensitivity to low freq also has a roll off, this I have books to support, and a ported box tuned very low will "sound" far more linear than a sealed box because of the increased low end compensates for it.


Regardless, whichever the OP chooses I am sure will be plenty loud & sound great. I was simply sharing what I would do, and I am an extremely picky son-of-a-bitch in regard to my sound systems.

[stipud]

You are running 2 subs on 200w each, dropping 1 and bridging the amp lets you run 1 sub at 400w, which changes nothing. Output should be the same in either case. About the same thing as you just said.

But the output isn't the same. 400w to two subs (200w each) is still 3dB louder than 400w to a single sub, because you have double the cone area. 400w is constant in the above scenario; it has nothing to do with how much power per woofer, but the total power. Or am I just not reading your point right?

There is not very much space in a 350z , and a sealed box housing two 10's cannot be built big enough to get a very smooth freq response, and a ported box would be almost out of the question.
Dropping to 1 sub literally doubles the amount of airspace you can give to the one sub, which would greatly flatten the freq response and noticeably increase the low end response. Running 2 subs in a borderline too small box will only reinforce the already poor freq response. This is the case for sealed boxes, I am not even talking about ported yet. So the 1 sub wont be any louder or quieter than the pair, but large change in box volume will positively impact sound quality & linearity of the bass response.

Now, ported enclosures. Drop the single sub into a ported box, and tune it very low (25~28hz) and you are not just "boosting" the bass at the tuned freq but instead extending the freq curve, making this 10" sound much more like a 12" or 15".
The ear's sensitivity to low freq also has a roll off, this I have books to support, and a ported box tuned very low will "sound" far more linear than a sealed box because of the increased low end compensates for it.

I hear you, but in my opinion the RSDCs are already geared for low enough bass from the get-go, even in a small box. My 10 plays 3dB higher at 20Hz than it does at 60Hz in a .6cuft box. I found the bottom end unneccessarily bloated in a ported box. We have tried them in bigger sealed boxes, but they do not seem to improve like the original RSDs did as the size increased. The original RSDs would make a great IB woofer IMO. Instead, we found the competitions only got more detailed in smaller boxes, with 10's best at .5-.6 and the 12's from 1-1.25.

Of course this is all subjective testing, but for those of us who have tried, we have all came to the same conclusions. If you like seriously deep bass, porting will definitely extend the frequency below the natural curve in a .6cuft sealed box. Just make sure you have adequate midbass up front to compensate for it.

Regardless, whichever the OP chooses I am sure will be plenty loud & sound great. I was simply sharing what I would do, and I am an extremely picky son-of-a-bitch in regard to my sound systems.

This is something we can all agree on

[Rob221]

I have a set of CDT Audio EF-61 6.5"s. I thnik these have an adequate midbass up front to compensate for it. Not sure what you guys think adequate midbass would be.I listen mostly to Electric Blues,Oldies and rock and roll.I do listen to some of my sons songs once in awhile,alot of bass in that kind of music lol.

[stipud]

I have a set of CDT Audio EF-61 6.5"s. I thnik these have an adequate midbass up front to compensate for it. Not sure what you guys think adequate midbass would be.I listen mostly to Electric Blues,Oldies and rock and roll.I do listen to some of my sons songs once in awhile,alot of bass in that kind of music lol.

For the RSDC's sealed they should be perfect. If you haven't done so yet, you should consider sound deadening over your doorpanel completely.

[Rob221]

Good to hear.Yeah the hole car has deadener in it. I have put sound deadening every where but the head liner.