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Unhappy, need help from the big dogs with my sub setup
Hey guys, I'll give you the skinny...
After a ton of research I built a large custom fiberglass enclosure (sealed) basically two sections on either side of the strut bar:
1. one large MDF wedge section between the speaker bar and strut bar (open on strut bar side)
2. The mounting face section is MDF on the other side of the strut bar and I just glassed to the shape of the sheet metal for the bottom and the top is just sort of like a tunnel through the strut bar into the wedge
*Sort of like a larger and more complicated version of the zenclosures box if that gives you a good idea..*
It holds (2) 12" RE SE powered by a kicker kx1500.1 @ 2 ohms. Now here is the thing, I just simply am not happy. It is pretty loud, it can make your head hurt a bit but it is not enough for me. I thought it would be plenty and everyone and all of the research told me it would be, but it just isn't cutting it, I need more . It is hard to explain and I know people are going to say you can't have everything but it just is not doing what I want on any end of the bass spectrum, it isn't tight and chest thumping at all nor is it hitting the lows strong as I would like...
Not that I want to run it all of the time, but I at least want the capability to just produce jaw dropping, earth shaking, sh*t your pants bass.. I want it loud and hard-hitting, punchy but still banging the lows with authority while maintaining clarity and quality within reason. Essentially just ridiculous bass, more than I can handle, I want it to be too much and then I'll back it off a bit. I'm open to suggestions and ideas, particularly hoping Bing, SPL, or some other z audio experts and heavy hitters can shine some light. **Now I know the box might be your first thought but I am building a simple sealed with the same space req. just to test the output before I rule the subs out as not diesel enough. If they strongly outperform my current fiberglass than something is wrong with my box and I will reconsider these subs in a proper ported box. But for right now let us assume that there is nothing wrong with my current box, it just is not suitable for my goal output level.**
I'm open to any types of setups, ex: large single 15" ported, dual 12's ported, ect. Open to changing my amp as well, 1 or 2 ohm setups but please make sure it is stable I want a safe daily setup I'll be getting the equipment off of ca.com classifieds most likely, so please place your pricing accordingly to car audio forum pricing. I don't want to spend more than $300-400 on an amp but if absolutely necessary I can go up to like 500 which I've seen some Sundown SAZ-3000D's go for. As for Sub/s, same thing pretty much, I'll take a solid pair or a beastly single for $300-500. I figure I can get ~$275 for my kx1500 and ~$300 for my pair of RE's and I wouldn't mind spending a couple hundred more bucks on top of that. I already have the beastly kicker hyperflex dual amp 0/1 gauge kit so I have the wiring to handle any amp you suggest. I'm open to equipment manufacturers that are well known and liked by the community, like DD, RE, Fi, sundown, SI, kicker... I'm thinking about a 15" RE XXX or a 15" DD if I was to go big single, or a nightshade.. just some ideas
PLEASE bring on your suggestions... on what you have heard/worked with only please, I look forward to some good input and discussion, Thanks!
For the kind of bass you are looking for there are a few SPL guys here, one that I know could give you what you want would be 350zspl, but I haven't seen him around here much lately. Maybe try PM'ing him a link to this thread or something.
Otherwise, I'm sure a couple other guys might be able to help you out. I'm more of an SQ guy, so I can't offer too much to you.
Since you say that there's nothing wrong with your current set up I'll assume you did the Thiel-Small parameter work and matched the physical volume of the enclosure to the parameters of your speaker elements.
More power - doubling your power amplifier size to 3000 watts will give you a 3dB increase in sound - you'll just barely notice that 3 dB by the way. I would suggest about 15 dB worth of additional amplifier in my experience to give you a bigger kick. 15 dB gain above a 1500 watt amplifier is going to require about 46 thousand more watts worth of power. To be exact 45,934 watts.
If you're willing to put up with just 12 dB you can get by with just and additional 22,275 watts worth of power. Figure ten batteries will give you a half and hour to twenty minutes worth sound.
First remember that sounds this loud are damaging. Forever. As every conscience moment of every day. I suffer from tinnitus which manifests itself as a high pitch ringing in my right ear and a slightly lower volume and a different frequency in the other ear. That's what a really good sound system can do for your life in about four to six hours of exposure - 30 years of noise.
The worst part is trying to go to sleep with the noise. Over the decades since the event I've learned to tune it out ... but its there now and forever. There is no cure, there is no treatment. Hit that amplitude and the tiny hairs in your inner ear shatter and never ever ever return.
If you'd like to save yourself the expense and just go to that level of pain you can come by and visit me. A couple sets of nice SVS subwoofers, a few Yamaha amplifiers and a couple of CDs later and your hearing will be destroyed forever.
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Super Black 2005 35th Anniversary
Not much of a SPL guy, but the first thing that jumps out at me is that you are using a sealed type set up. Usually when I see a SPL set up, it is some type of ported enclosure and it is tuned for maximum output at the vehicles frequency.
I have been out of the game for a while so I don't have up to date info on the model numbers you are talking about.
However, 2 12" subs and +/- 1500w should be enough to make breathing difficult. I was just shy of 140db with two 12's and 400 watts in a sedan. (subs in the trunk) -Full volume caused slightly blured vision and pressure levels that felt like a bad head-cold.
Assuming the amp is supplying 750 watts to each sub, in phase, in a good enclosure, and the subs can make use of all the power.... your setup, in a Z, should be at least 146db easy.
If your equipment is legit...
The most common cause of "bad bass" in dual-sub setups is phasing problems. (Each sub sounds good by itself, but they sound bad together.)
The second most common problem is the enclosure.
A) Not enough airspace so the subs punch hard with "high" bass but poduce a "BING!" or "BAH!" sound on low notes instead of a "BOOOOOM".
B) Air leaks. Fluttering air sounds on low notes is a big giveaway for this problem.
C) poorly-tuned porting. (But I think you are running a seald enclosure so this shouldn't come into play) Too much airspace, and the subs bottom out too soon.
Third is the way the sub/enclosure is "loaded" into the vehicle. Some may dissagree with me on this, but I think the stock sub location is a perfect example of poor loading.
The strut tower, facing to the rear, is good loading for a sub(s) in the Z. (IMHO)
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Quaife LSD, SSR Comp-H wheels, RS*R Ti2000 springs, Hotchkis V2 sway bars, Koni "Yellow" adjustable shocks, JWT clutch/flywheel.
For the kind of bass you are looking for there are a few SPL guys here, one that I know could give you what you want would be 350zspl, but I haven't seen him around here much lately. Maybe try PM'ing him a link to this thread or something.
Otherwise, I'm sure a couple other guys might be able to help you out. I'm more of an SQ guy, so I can't offer too much to you.
Thanks for the response, yah I've talked with him before, I called for his help in my initial post ("SPL") he uses a 15" sub in a ported enclosure and I'm leaning towards that so I'll wait for his response
Quote:
Originally Posted by Paul350Z
Since you say that there's nothing wrong with your current set up I'll assume you did the Thiel-Small parameter work and matched the physical volume of the enclosure to the parameters of your speaker elements.
More power - doubling your power amplifier size to 3000 watts will give you a 3dB increase in sound - you'll just barely notice that 3 dB by the way. I would suggest about 15 dB worth of additional amplifier in my experience to give you a bigger kick. 15 dB gain above a 1500 watt amplifier is going to require about 46 thousand more watts worth of power. To be exact 45,934 watts.
If you're willing to put up with just 12 dB you can get by with just and additional 22,275 watts worth of power. Figure ten batteries will give you a half and hour to twenty minutes worth sound.
First remember that sounds this loud are damaging. Forever. As every conscience moment of every day. I suffer from tinnitus which manifests itself as a high pitch ringing in my right ear and a slightly lower volume and a different frequency in the other ear. That's what a really good sound system can do for your life in about four to six hours of exposure - 30 years of noise.
The worst part is trying to go to sleep with the noise. Over the decades since the event I've learned to tune it out ... but its there now and forever. There is no cure, there is no treatment. Hit that amplitude and the tiny hairs in your inner ear shatter and never ever ever return.
If you'd like to save yourself the expense and just go to that level of pain you can come by and visit me. A couple sets of nice SVS subwoofers, a few Yamaha amplifiers and a couple of CDs later and your hearing will be destroyed forever.
I picked up the condescending attitude even before I got to the unnecessarily sarcastic math lesson on that which I already know, but not before I realized that you meant "Thiele" as that would be the correct spelling. I'll answer courteously anyways; I appreciate the warning about the hearing damage and it is unfortunate that it has happened to you but lets hope I am more fortunate and careful with my listening. For now, how about you let me get some real help on that 3dB gain I would love to have.
EDIT: And I just noticed, you are a moderator? And on top of that this is the kind of advice you give out in your own section? Unhelpful sarcasm about how I can wrangle up 45,000 more watts? On to the next one..
Quote:
Originally Posted by THEDUKE
Not much of a SPL guy, but the first thing that jumps out at me is that you are using a sealed type set up. Usually when I see a SPL set up, it is some type of ported enclosure and it is tuned for maximum output at the vehicles frequency.
Yeah I had thought 2 12's was overkill in the first place so I went sealed for the quality. In my post I mention switching to a ported enclosure, I'm open to the idea and I think that is where I'm headed.
Quote:
Originally Posted by Z1NONLY
I have been out of the game for a while so I don't have up to date info on the model numbers you are talking about.
However, 2 12" subs and +/- 1500w should be enough to make breathing difficult. I was just shy of 140db with two 12's and 400 watts in a sedan. (subs in the trunk) -Full volume caused slightly blured vision and pressure levels that felt like a bad head-cold.
Assuming the amp is supplying 750 watts to each sub, in phase, in a good enclosure, and the subs can make use of all the power.... your setup, in a Z, should be at least 146db easy.
If your equipment is legit...
The most common cause of "bad bass" in dual-sub setups is phasing problems. (Each sub sounds good by itself, but they sound bad together.)
The second most common problem is the enclosure.
A) Not enough airspace so the subs punch hard with "high" bass but poduce a "BING!" or "BAH!" sound on low notes instead of a "BOOOOOM".
B) Air leaks. Fluttering air sounds on low notes is a big giveaway for this problem.
C) poorly-tuned porting. (But I think you are running a seald enclosure so this shouldn't come into play) Too much airspace, and the subs bottom out too soon.
Third is the way the sub/enclosure is "loaded" into the vehicle. Some may dissagree with me on this, but I think the stock sub location is a perfect example of poor loading.
The strut tower, facing to the rear, is good loading for a sub(s) in the Z. (IMHO)
See this is what has me thinking that I have plenty already, hence why I am flipping back and forth between ideas, there could be some air leaks in my fiberglass sections.. Thanks for the good advice
I picked up the condescending attitude even before I got to the unnecessarily sarcastic math lesson on that which I already know, but not before I realized that you meant "Thiele" as that would be the correct spelling. I'll answer courteously anyways; I appreciate the warning about the hearing damage and it is unfortunate that it has happened to you but lets hope I am more fortunate and careful with my listening. For now, how about you let me get some real help on that 3dB gain I would love to have.
EDIT: And I just noticed, you are a moderator? And on top of that this is the kind of advice you give out in your own section? Unhelpful sarcasm about how I can wrangle up 45,000 more watts? On to the next one..
... and a degreed electrical engineer with +30 years of experence in radio and television acoustics!
Power is power is power. Audio amplitude is power/energy and since you removed any changes to your acoustical gain with assume my speakers are perfect that only leaves electrical power. If you can spell Thiele correctly I'll assume you went though his work and have settled on a closed box for it's accuracy rather than a ported or even a loaded horn ot transmission line design. With the Z there just isn't the room for much of that anyways.
Engineering is governed by laws - with a transducer there are but two ways that I know of to increase the energy produced - change the transducer or drive it with more signal. There's so little physical room to play with the speakers you're not going to gain much - even porting and changing your Qtc to peak bass is only going to give you another three, may be six dB in gain - not knock your socks off which in my experence is more like 12-15 dB more gain. Additional wattage is governed by another one of those engineering laws which state to get a 3 dB increase in power you'll need to double the size of the amplifier - the decibel scale is logarithmic - and there for the stupid large amplifiers. Add a second 1500 watt amplifier and you'll gain that 3dB, jump to 6KW for 6 dB, 12 Kw for 9 dB ... there is a just huge point of diminishing returns.
If you had given me a blank sheet of paper and said change anything I would have suggested:
1. Running a more sensitive set of speakers
2. Rather than running a second order (sealed) speaker running a forth order (bandpass) giving up a bit of accuracy for amplitude. Starting with a more sensitive speaker is always a good idea for SPL competition where an extra 2dB in a speaker can be free or cheap ... where gaining that in a bigger power amplifier is tough and expensive.
3. If you're fixed on a second order enclosure change your Qtc a bit higher ... like adjusting it 0.2 at a time until you peak the bass amplitude while giving up a bit of the bandwidth. Run the Thiele-Small formula again and adjust the volume of the box down while watching the output amplitude increase.
I have been warning people about just how stupid easy it is to blow your hearing here for four years now and I'm not going to stop. Back when I damaged my hearing I had to spend about $25,000 on high end gear bought in Japan and assembled here. Now I could do it with a tenth of that budget today. Sort of like on the gun range and I see someone mishandling a firearm I just can't help myself warning them. I suppose I shouldn't really care what other people do to injure themselves ... but often people who wouldn't think of mishandling a loaded firearm will gladly subject themselves to huge levels of audio. Be careful with what hearing you have left. If I didn't care I wouldn't say anything.
I sorry, I don't mean to come off condensing, I'm just have a sense of humor that might not be coming across. It's like my daughter asking for a unicorn and then saying I can't touch her pony.
I have helped at least two guys that worked for me win SPL competitions in Washington state. I got a set of the rules from the judges and looked for weaknesses to exploit. Those rules of engineering again! Once they allowed the contestant to bring in their own music. There were strict levels on the sizes of the woofers - different competition classes. So I remixed the music to compress the heck of out the lower frequencies.
Your 1500 watts worth of amplifier are only working when they're working. You can process the music to compress it but most of today's modern music is so overly compressed that it has no more room for any additional compression. I got to meet Bob Orban at a NAB, he invented the compression products that bare his name used by a large number of AM and FM radio broadcasters. He studied the compression that music has gone through sampling music from each of the last four decades. In each passing decade about 10 dB worth of compression has been added by the producers knocking the heck out of the low end - today's music is loud, louder, and loudest. Depending on how old the music is that you're listening to you can pre-process the music or add a compressor into the system. That pre-processing can be done as you burn your disks on your computer.
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Super Black 2005 35th Anniversary
Last edited by Paul350Z; 11-04-2009 at 01:12 PM.
Reason: Spelin!
You know, having been around these forums for a day or two myself I can say that Paul350Z has thrown his $.02 about hearing loss many times. I applaud him for it. It's like someone coming on here and saying "I hold the blade of a circular saw and turn it on, how can I make the blade sharper?" and someone saying "Be careful , you can amputate your hand like that!" What he says is true and some people just don't know any better. Take it as a friendly warning as opposed to a scolding.
But back to your question -
I think working with the 'budget' you gave yourself in the first post, which in the world of huge SPL seems a little constraining, your best bet would be to look for more efficient (higher sensitivity) subs first. See what that does for you. Then if you need more, look to change out your enclosure for a ported one. Lastly is to add more power because that costs the most, and you have a good amount already.
I know I pretty much copied what Paul350Z suggests, but it makes sense to me. I have 20 years in the car audio field, mostly as a hobbyist, but also as an installer back in the early 90's.
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It's good to be back
Last edited by StreetOC192; 11-05-2009 at 05:09 AM.
I’m going off-topic here, but I read Paul’s comments about tinnitus and would like to elaborate. I’ll keep it brief.
As Paul mentions, tinnitus is just an awful affliction. Ringing and/or buzzing in your ear 24/7 (day and night) can drive you to almost any end to relieve this horrible condition.
Tinnitus is linked to many causes, but SubW’s in cars is an identified and confirmed source. With that in mind and how bad this affliction really is, you need to exercise caution.
Many modern recordings take advantage of a SubW, and sound better with this equipment. To protect yourself you only need to insure that your low frequency output is reasonable and safe. A car’s interior is small and can intensify this type of sound. My measure of safety is that you should not hear or feel the SubW “thump” if you are outside the car.
I don't think Paul is bering sarcastic. I think he really cares and offers advice from personal experience.
the XXX is a BEAST. The top of my list in dream subs....also, the Fi BTL's are extremely popular in price vs. performance....either would for sure give you that super low bass you want. I'd be concerned about the volume of the space in the Z though, a large sub usually requires lots of airspace, and going ported just compounds that problem.
I use audiobahn aw1000's (10" high excursion). When i ran 2 of them in a ported box with 1000 watts on both of them i managed 143 db's. I only run a single sub now so remove 3db's off that.
You'll have more surface area with 2 12's over a single 15". With decent high excursion subs and properly tuned box you should be hammering some sound out with that power.
The thing with fiberglass boxes is making sure it's thick enough. It takes a very thick layer of fiberglass to be rigid enough for high spl subs like that.
Unhappy, need help from the big dogs with my sub setup
. It is hard to explain and I know people are going to say you can't have everything but it just is not doing what I want on any end of the bass spectrum, it isn't tight and chest thumping at all nor is it hitting the lows strong as I would like...
I was just shy of 140db with two 12's and 400 watts in a sedan. (subs in the trunk) -Full volume caused slightly blured vision and pressure levels that felt like a bad head-cold. 
On to the next one..
