8 Ohm or 2 Ohm for SQ Build

[trumpet 5,000+ posts]

Why are you not going ported? That myth about sealed having better SQ is a myth. Most who think that have only used or heard prefabs

There are legitimate reasons a ported enclosure might not sound as good as a sealed enclosure with the same subwoofer and amplifier. The #1 reason is the change in frequency response, which can be corrected with an EQ, but not a 3-band EQ.

 

[LosIsATool 5,000+ posts]

There are legitimate reasons a ported enclosure might not sound as good as a sealed enclosure with the same subwoofer and amplifier. The #1 reason is the change in frequency response, which can be corrected with an EQ, but not a 3-band EQ.

Very true. If he wants full SQ which I feel he is looking for a better EQ is in order.

 

[budgetkiller 10+ year member]

Why are you not going ported? That myth about sealed having better SQ is a myth. Most who think that have only used or heard prefabs

The box my SA12 is in right now was custom built for my last car by the man I bought the sub from. It's birch plywood, around 1.75 cu. ft (a tiny bit small I know...sports car), tuned somewhere around 30-35 Hz and up-facing rear-firing. It sounds great, especially below 50 Hz or so, but it's not quite as tight as I would like it to be. Sealed subs just seem to have a certain clarity that ported struggles with. I think it might have something to do with the air pressure constantly pushing/pulling the cone back to zero again. Double-bass kick drums for example are something I think sealed does better. Don't get me wrong, I LOVE borderline subsonic bass rumbles, but SQ is the objective here. I know ported responds lower, but since I'm going from a 12" to two 13.5" drivers shouldn't that help compensate for any lost low notes? The final straw was that I've never built a ported box before and I know that it's a science in and of itself. Sealed is easy, as far as I understand it's a matter of picking your firing angle/direction, doing your math correctly and building it to the proper size. It will be a while before I actually build a box, so if I'm making a mistake please let me know. Hopefully you can follow my reasoning here. Also, if I ever find the time to fiberglass some door panels, I have a pair of 8 inch midbass drivers for my next step up in the spectrum...just so you know what I eventually want to try and blend to. Also, trunk space is much more abundant now as I sold my 80's sports car (and bought a stereo with the money) and now drive a full size sedan.

 

[budgetkiller 10+ year member]

Very true. If he wants full SQ which I feel he is looking for a better EQ is in order.

Already picked up a Kicker 30 band graphic EQ. //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

 

[LosIsATool 5,000+ posts]

A lot if not all of the top SQ cars run a ported design or bandpass. That kick drum should be coming from your midbass drivers

 

[LosIsATool 5,000+ posts]

Already picked up a Kicker 30 band graphic EQ. //content.invisioncic.com/y282845/emoticons/biggrin.gif.d71a5d36fcbab170f2364c9f2e3946cb.gif

That is not going to give you time alignment and individual channel EQ. Its basic

 

[budgetkiller 10+ year member]

That is not going to give you time alignment and individual channel EQ. Its basic

I didn't realize ported was used in SQ. I think I'm going to research building ported enclosures now. As for the EQ, I know it's just basic. I was really sad to lose time alignment (used it on my HU on my previous build with phenomenal results) but I knew a 30 band EQ would probably benefit me more. Someday I'd like to get an Audison Bit One to play with, but considering I don't have mics or a RTA or even an O-scope, and that this is my first active build and a learning experience, and that I got 80% of my gear second hand for a lot less money, this will have to do for now. I also realized that the reality is I'll be lucky to have a half decent tune on this system within the next year just tweaking the 30 band and my DD X1.1. When I feel that I have a handle on things, and that I've gotten pretty close to the full potential of the gear I have, then maybe I'll invest in a Bit One. That's what I figured anyways. What do you guys think?

 

[trumpet 5,000+ posts]

When your subwoofer is not playing much above 50 Hz there is nearly nothing of kick drums coming from that. Some music will have extra bass added in the mixing and/or mastering process of the recording to make the kick drum sound more meaty and fat, but you will not be hearing that kind of kick drum in reference quality recordings. The kick drum is almost entirely coming from your speakers, at least the real detail that makes us differentiate between one drum kit on a recording to another drum kit on a different recording.

As for a DSP, I would invest in that now instead of waiting. You can have a local shop install and tune it. In fact, I can help you find an expert locally to get your system sounding much better. Tuning time with a "big" equalizer can be cut down drastically with proper measurement equipment and a target frequency curve. When you have a target curve you eliminate the need to constantly tweak the EQ.

Regarding sealed vs. ported, I used to be a die hard sealed enclosure guy. It's important to acknowledge that some subwoofers do sound significantly better than others. I personally do not use subwoofers that tend to have poor performance in the upper bass/lower midbass region. If you can't audition before you buy, look at what gets reviewed as "transparent" or "dry" as these tend to be the more accurate sounding subwoofers. It means they can more easily blend with your midbass/midrange woofers and your ears aren't immediately drawn to the direction of the subwoofer.

 

[Justin braaapp]

Please do not take any advice from this idiot.

he's actually pretty d*mn knowledgeable...

 

[budgetkiller 10+ year member]

When your subwoofer is not playing much above 50 Hz there is nearly nothing of kick drums coming from that. Some music will have extra bass added in the mixing and/or mastering process of the recording to make the kick drum sound more meaty and fat, but you will not be hearing that kind of kick drum in reference quality recordings. The kick drum is almost entirely coming from your speakers, at least the real detail that makes us differentiate between one drum kit on a recording to another drum kit on a different recording.
As for a DSP, I would invest in that now instead of waiting. You can have a local shop install and tune it. In fact, I can help you find an expert locally to get your system sounding much better. Tuning time with a "big" equalizer can be cut down drastically with proper measurement equipment and a target frequency curve. When you have a target curve you eliminate the need to constantly tweak the EQ.

Regarding sealed vs. ported, I used to be a die hard sealed enclosure guy. It's important to acknowledge that some subwoofers do sound significantly better than others. I personally do not use subwoofers that tend to have poor performance in the upper bass/lower midbass region. If you can't audition before you buy, look at what gets reviewed as "transparent" or "dry" as these tend to be the more accurate sounding subwoofers. It means they can more easily blend with your midbass/midrange woofers and your ears aren't immediately drawn to the direction of the subwoofer.

I appreciate your offer for help, but to me half the fun of the hobby is learning how to do everything. They better I get at putting together and tuning stereos, the better they sound. I love the feeling when I get it the best it's ever sounded. Money is also a factor as anytime somebody else has to do something for me I have to pay them. I also run my own "business" in my free time doing basic installs for other people and friends. I take pride in saying that I did almost everything to my own system and I have spent days learning how to tune. I realize that with proper equipment it could sound a lot better, and someday I might invest in some, but right now I'm still figuring things out. I had a passive system in my last car and was told by a shop owner that I "...Did pretty well for what I had." Got a new car and figured the next step was to go active; DSP is next after that. I'm by no means trying to argue here, I'm just trying to explain my situation and logic. Feel free to critique it. Didn't know that about the kick drum though. I've actually wondered where that lies in the spectrum.

As for the target curve, I might have it confused with something else but for SQ isn't the target curve essentially flat? That's my goal for now anyways. I'd loved to have taken a RTA and see where my last system landed just to know how decent or bad it really was and what I didn't hear.

Regarding what you said about subwoofers, very good advice and I will definitely keep that in mind in the future. I also am going to have to do some research on my w3's and see what people say regarding box design. Thank you.

 

[trumpet 5,000+ posts]

As for the target curve, I might have it confused with something else but for SQ isn't the target curve essentially flat? That's my goal for now anyways.

For the short answer, no, a flat target curve is not a good goal. Noise in the vehicle masks the lower frequencies, so we need to boost them. Even if you listened to the system in a quiet place with the engine off a flat curve sounds boring.

The long answer: Target Curve Comparison

I really enjoy the Harman International curve, #1 , in that thread.

 

[budgetkiller 10+ year member]

For the short answer, no, a flat target curve is not a good goal. Noise in the vehicle masks the lower frequencies, so we need to boost them. Even if you listened to the system in a quiet place with the engine off a flat curve sounds boring.
The long answer: Target Curve Comparison

I really enjoy the Harman International curve, #1 , in that thread.

Thanks for the link. I need to join that forum to get access to everything, but I did read through #2 , the C. Labs Curve and learned a lot. When I find the time I'll have to read through more of them.

Anyways, regarding the original thread topic, I'd like to get some opinions on a third option. I did some light research into infinite baffle set ups last night and thought to myself, what if I ran 8 Ohms on an IB set up? I read the JL W6 and W7 perform quite well in IB, and since I'm running two W3V3s, which from what I understand are essentially a cheaper version of the W6, and since I also read that only about half the watts are required vs sealed, I think it might be a real option. Haven't researched deep into the W3 specs to see exactly how compatible it is yet, but keep in mind I have that graphic EQ as well. Also haven't measured the rear shelf yet, but visual estimates are telling me that it's just big enough to accommodate them (Not too important since I have a plan to stealth mount them). I'm not asking anybody to do my woofer specific homework here, I've just read very good things about IB and this idea popped into my head. It sounds like it could be the best of both worlds; good output and great SQ. What does everyone think?