Sub Tuning Tips

**shakes** · 04-16-2004, 01:28 PM

Originally Posted by brrman

yeah pout the EQ at 90 and set the amp to around 80. Thats what I have and I get amazing punch out of my sub. Took me close to a month of fiddling before I got my sound the way I wanted it. BTW I have the same Clarion EQ in my car also.

I'll give it a shot this weekend and see if i get better response.

How do you like your infinity perfect 10.1? that's the one i've got my eye on ... Does it sound ok with just having one?

**Banderon** · 04-16-2004, 02:09 PM

Originally Posted by shakes

another random question ... if you have a dual voice coil sub ... does it hurt the sub to hook up just one vc?

If you had a V12 and you disabled 6 cyclinders so it'd only run as a V6... would it hurt the car?

The real question is: Why get the V12 if you're only going to use half its power?

**TaylorMade** · 04-21-2004, 09:21 AM

Hey Shakes, sorry that I haven't replied, I forgot about this thread. To answer your question, no, I don't fill the entire box, I just use spray glue and coat the sides. In essence you are fooling the sub into thinking that it's in a smaller box. The reason that most folks don't have a divider in the middle of the box is they're usually running bridged (mono) and not in stereo. If they were running in stereo the speakers would move at a different times rather than at the same time and therefore screw things up airflow wise.

**brrman** · 04-21-2004, 10:30 AM

Originally Posted by shakes

I'll give it a shot this weekend and see if i get better response.

How do you like your infinity perfect 10.1? that's the one i've got my eye on ... Does it sound ok with just having one?

The Infinity totally rocks, man. Really tight bass. I mainly listen to rock and some techno/trance. It really pounds when you want it to. Not to mention it flew off my car roof one day (in the fiberglass box) when I was workin in the trunk and needed to run out to the hardware store... Thing still tickin!

One sub is perfectly fine for me - it can push more than I require for my listening pleasure - and I like it loud.

**shakes** · 04-21-2004, 11:12 AM

Originally Posted by TaylorMade

Hey Shakes, sorry that I haven't replied, I forgot about this thread. To answer your question, no, I don't fill the entire box, I just use spray glue and coat the sides. In essence you are fooling the sub into thinking that it's in a smaller box.

ah ... good times ... I may need to try to add a little. there's a little bit too much thud sometimes, and i suspect there's just a little bit too much air in the box for the sound i want.

Originally Posted by brrman

The Infinity totally rocks, man. Really tight bass. I mainly listen to rock and some techno/trance. It really pounds when you want it to. Not to mention it flew off my car roof one day (in the fiberglass box) when I was workin in the trunk and needed to run out to the hardware store... Thing still tickin!

awesome ... that's definately the way i'll be going then. I've been watching ebay for th 10.1s ... both svc and dvc ... can't decide which i want yet. Trying to make myself hold off for another mointh or so tho ... i've been spending a lot of money on this system lately and I still need a few other things (new power supply, etc)

Originally Posted by Banderon

If you had a V12 and you disabled 6 cyclinders so it'd only run as a V6... would it hurt the car?

The real question is: Why get the V12 if you're only going to use half its power?

well ... my amp can put out 350W RMS x 1 @ 4Ohms bridged... so if i got the single voice coil version that'd be fine.

But I'm unsure if I want just one, or two of these. If i get two, then I can't run in bridged mode very effectively. The amp only gives off 170W x 2 @ 4Ohms ... so in that case I'd want the dual voice coil version so I could run the subs as a 2 Ohm load and get more power per channel.

But ... since I'm unsure whether or not i want one or two subs, i was thinking I'd just get one, see how it sounds, and go from there. But I wouldn't want to get one singla voice coil, then decided i need two and have to get two dvcs and sell the svc. And of course i wouldn't want to run the dvc in 8Ohm mode bridged ... as that loses me power. see my dilema?

Anyway ... I think more than likely i'm just going to stick with one sub ... so I may just get the svc and be done with it.

**MrPerfectionest** · 04-21-2004, 11:57 AM

Quote:
Originally Posted by TaylorMade
Hey Shakes, sorry that I haven't replied, I forgot about this thread. To answer your question, no, I don't fill the entire box, I just use spray glue and coat the sides. In essence you are fooling the sub into thinking that it's in a smaller box.

ah ... good times ... I may need to try to add a little. there's a little bit too much thud sometimes, and i suspect there's just a little bit too much air in the box for the sound i want.

This is incorrect, in essence adding polyfill makes the sub thinks it is in a larger box. The polyfill dissipates energy (in the form of heat from vibrating) which the sub 'feels' as more damping. More damping happens from a larger box (up to the point the box gets too large and begins to act like an infinite baffle arrangement). In general if you want the flattest most transparent sound for a given sub, you build a box such that the Q of the box is .707 based on that subs theile-small parameters. In my experience some sub manufacturers that give pre-calculated box dimensions will generate Q values lower than .707. This will mean the speaker (sub+box) will have an output gain (ie more bass) near the lower F3 point of a .707 Q box. Of course a manufacturer will want to do this so their sub sounds louder and boomier than the other manufacturer so that people will buy their subs.

In general you are attacking the problem from the wrong angle. Most of the punch in rock music is easier to generate with good midbass speakers. Take note that many hardcore sound quality car audio competetiors will stuff 8" midbass drivers in their kick-panels where no normal car audio buff would do this. You are also working against the problem that car audio equipment (especially subs) is made to be tougher than what you find in your home (ie rubber surrounds, thicker cones) which also makes them more sluggish than ideal and a 10" or even some good 8" subs would be much more ideal than a 12" for rock tracks.

But this is all well and good in hindsight, since you are stuck with the equipment you have. You really need to get above 90hz a bit to get a lot of the punch that happens in rock tracks. Only problem is this can start to color (muddy) the lower end bass a bit and limit overall output if you aren't careful. Also, if you don't have some really good components up front then using two crossovers at your sub is probably leaving out some sound information in your setup. In general you want the crossover between the two set at the same frequency and having both of them rolling off at the same rate. So no need for both crossovers (they could also introduce some unnecessary phase shifting). Just try out one of them and I would try to go a bit higher than 90hz.

But like someone else said, its impossible to tune it without hearing it.

**TaylorMade** · 04-21-2004, 12:05 PM

Ah yes, that must be what I meant to say.

heh heh... it's been about 8 years since I've done car audio seriously. We must have put the polyfill in SMALL boxes to make the sub think it's bigger. I did that with my two 12" Polks because I build a small box for them (didn't want to lose that much cargo space). Sorry for any mis-information Shakes (and anyone else who ran to the store).