Need help selecting a subwoofer. Infinite baffle questions.
08-20-11, 03:16 AM
#16
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If you don't want to mess with REW and setting up your laptop, http://www.pvconsultants.com/audio/eq/peq.htm works as well. You can be up and running in as long as it takes you to make a test tone disc. I used 10 second sine waves at frequencies matching the values on the PEQ spreadsheet. Write down the SPL number of each frequency into the spreadsheet and apply the correction values (simple check box as far as I remember). Look at the graph.
It is made to so simulate a 12 band parametric equalizer called the Behringer Feedback Destroyer. That's what I and a lot of home theater enthusiasts use to tame the response of your home theater subs. My dual 15" TC-3000/Behringer EP-2500 system went from boomy to perfect in about an hour. The predicted response after applying the EQ filters measured spot on as well.
It is made to so simulate a 12 band parametric equalizer called the Behringer Feedback Destroyer. That's what I and a lot of home theater enthusiasts use to tame the response of your home theater subs. My dual 15" TC-3000/Behringer EP-2500 system went from boomy to perfect in about an hour. The predicted response after applying the EQ filters measured spot on as well.
08-21-11, 11:21 PM
#17
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I replaced the head unit in my '98 LS400 (pioneer original) and as expected I'm somewhat disappointed with the factory sub. I don't quite know why but the sub sounded a lot better with the factory equipment and no matter how I tune it I'm just not happy. It recreates strong sub 50hz signals surprisingly well, but generally anything above that sounds muddy and it also sounds like the speaker is maxing out it's travel. I have my LPF set to 50hz with a 12db slope so it sounds somewhat decent, but I know I'm missing a lot of upper bass frequencies and it's quite apparent in a lot of songs. Okay so I'm asking too much out of a 13 year old paper sub.
I want to install a replacement driver in the stock location. I don't want a sub box. The problem is my limited understanding of selecting the right driver for an IB setup, and I want to do this the right way. Through some research I'm hearing things about cabin gain, and QTS (I know a bit about TS parameters but not enough). Obviously going with another 8" would be the easiest, but I'll do the work to sub-mount a 10" to the rear deck if it's really worth the trouble. I think an 8" might be okay, and that simply having a better quality speaker would make all the difference in the world. I'm running an Audiopipe APSM-1150 rated at 150watts @4ohms. Not the most powerful amp in the world but from what I understand I wont actually need much power.
Here's some that I'm looking at:
http://www.crutchfield.com/p_114D308...D4.html?tp=111
http://www.crutchfield.com/p_20610C8...nvpair=FFSize|[rank6]8%22&tab=features_and_specs
On this one the shallow mount idea is nice but the QTS is absurdly high at 1.64
http://www.crutchfield.com/s_130SW84...nvpair=FFSize|[rank6]8%22
Any suggestions?
I want to install a replacement driver in the stock location. I don't want a sub box. The problem is my limited understanding of selecting the right driver for an IB setup, and I want to do this the right way. Through some research I'm hearing things about cabin gain, and QTS (I know a bit about TS parameters but not enough). Obviously going with another 8" would be the easiest, but I'll do the work to sub-mount a 10" to the rear deck if it's really worth the trouble. I think an 8" might be okay, and that simply having a better quality speaker would make all the difference in the world. I'm running an Audiopipe APSM-1150 rated at 150watts @4ohms. Not the most powerful amp in the world but from what I understand I wont actually need much power.
Here's some that I'm looking at:
http://www.crutchfield.com/p_114D308...D4.html?tp=111
http://www.crutchfield.com/p_20610C8...nvpair=FFSize|[rank6]8%22&tab=features_and_specs
On this one the shallow mount idea is nice but the QTS is absurdly high at 1.64
http://www.crutchfield.com/s_130SW84...nvpair=FFSize|[rank6]8%22
Any suggestions?
08-23-11, 07:49 PM
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If possible could you run this sub through your software?
I picked it up on diymobileaudio. I am going to give it a shot with a jl 250/1
Focal Polyglass 11V5501
Fs - 43.7 Hz
Vas - 45.6 l
Qts - 0.82
Qes - 0.87
Qms - 14.4
Power Handling: 350W RMS
It is an old focal from 1997, nib.
Thanks
Ryan
I picked it up on diymobileaudio. I am going to give it a shot with a jl 250/1
Focal Polyglass 11V5501
Fs - 43.7 Hz
Vas - 45.6 l
Qts - 0.82
Qes - 0.87
Qms - 14.4
Power Handling: 350W RMS
It is an old focal from 1997, nib.
Thanks
Ryan
08-23-11, 08:10 PM
#19
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Okay so I tried REW. Neat program BTW. Anyway, so I calibrated my sound card and SPL meter as instructed, turned off the LPF,set the EQ to flat and ran the test. Here's the result. This is the stock 8" Pioneer sub for those just tuning in.
What's with that dip at 60hz? Thinking it was an anomaly with my test equipment I tested the only other available subwoofer I have with me, my computer speakers, and the dip is not present (and I am now impressed with my logitech speakers flat curve).
What's with that dip at 60hz? Thinking it was an anomaly with my test equipment I tested the only other available subwoofer I have with me, my computer speakers, and the dip is not present (and I am now impressed with my logitech speakers flat curve).
08-24-11, 04:46 AM
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I've never seen anything like that. Do you have another car to test the software with? Home audio system? That will eliminate the PC as the issue if it doesn't show up there.
Were your main speakers running during this? The only thing I can think of is that is your crossover point and something is out of phase. Worst case, that is a null in your system. In the home audio world, we would move the sub, move the primary seating or both. Neither of those are possible in a car.
Were your main speakers running during this? The only thing I can think of is that is your crossover point and something is out of phase. Worst case, that is a null in your system. In the home audio world, we would move the sub, move the primary seating or both. Neither of those are possible in a car.
08-24-11, 06:13 AM
#21
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Actually I did have my mains still turned on. Ooops. I'll try it again with them disabled. If that solves it I might try running the sub with the polarity flipped and see how it is with the mains on again.
Like I said, I ran the same test on my computer speakers subwoofer which is also an 8" and halfway decent for computer speakers. The response was much flatter, with no wacky looking dips.
I think you're right that 60hz is getting cancelled out for some reason. I have the HPF set to 80hz though.
Like I said, I ran the same test on my computer speakers subwoofer which is also an 8" and halfway decent for computer speakers. The response was much flatter, with no wacky looking dips.
I think you're right that 60hz is getting cancelled out for some reason. I have the HPF set to 80hz though.
08-24-11, 06:44 PM
#23
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Okies I tried it again with the mains turned off. Same thing. Tried it with the sub polarity reversed, same thing. I even tried it with the trunk open to see if it would have any effect. Doesn't seem to.
I'm pretty sure the meter's correct too because when I manually generate a tone starting from 50hz and gradually bringing it up to 80hz, I can actually hear the cancellation at 61-63hz. I also noticed the speaker grill vibrating/buzzing at this frequency. Could that be cancelling it out? I re-ran the sweep test while holding my hand on the grill so it wouldn't buzz and there was no difference.
I also tried running the test starting from 20hz, and it seems the sub is putting out maximum sound even though I have the (apparently useless) subsonic filter on.
That's probably what's bottoming out the suspension isn't it? I'm also guessing this cheap factory sub has pretty low QTS. The factory amp probably has a much more effective subsonic filter built in to prevent this. Can I add on a more effective subsonic filter to combat this?
edit: like this thing http://store.hlabs.com/pk4/store.pl?view_product=11
edit edit: I just ordered it. I think it'll help things greatly.
I'm pretty sure the meter's correct too because when I manually generate a tone starting from 50hz and gradually bringing it up to 80hz, I can actually hear the cancellation at 61-63hz. I also noticed the speaker grill vibrating/buzzing at this frequency. Could that be cancelling it out? I re-ran the sweep test while holding my hand on the grill so it wouldn't buzz and there was no difference.
I also tried running the test starting from 20hz, and it seems the sub is putting out maximum sound even though I have the (apparently useless) subsonic filter on.
That's probably what's bottoming out the suspension isn't it? I'm also guessing this cheap factory sub has pretty low QTS. The factory amp probably has a much more effective subsonic filter built in to prevent this. Can I add on a more effective subsonic filter to combat this?
edit: like this thing http://store.hlabs.com/pk4/store.pl?view_product=11
edit edit: I just ordered it. I think it'll help things greatly.
Last edited by anarchyx34; 08-24-11 at 07:58 PM.
08-25-11, 06:12 AM
#24
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Those bass blockers aren't the best. They base their crossover frequency on the input impedance of the amp. If your amp is different from their reference amp, then the crossover changes. Same as if you get a passive crossover for an 8 ohm speaker but decide to use a 4 ohm speaker. Crossover frequencies change.
Just looked up the wave length of 61hz and it is 5.6 meters (~18 feet). I don't see how you can have a null there. Can you move your mic to the rear seat and check? If the null is there then it is electronics and not caused by the cabin.
You can pull the woofer out and test it with Woofer Tester 3. Qts takes about 3 seconds to determine. I like a low Qts sub. I'd rather use EQ to lower the bass than have to boost it because it is too low.
Just looked up the wave length of 61hz and it is 5.6 meters (~18 feet). I don't see how you can have a null there. Can you move your mic to the rear seat and check? If the null is there then it is electronics and not caused by the cabin.
You can pull the woofer out and test it with Woofer Tester 3. Qts takes about 3 seconds to determine. I like a low Qts sub. I'd rather use EQ to lower the bass than have to boost it because it is too low.
08-25-11, 04:49 PM
#25
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Well I thought I had ordered it but apparently the order didn't go through. Do you have any other suggestions? The bass blocker isn't the ideal solution, that much I know, but surely it will make some difference wont it?
08-26-11, 05:07 AM
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You only need the bass blocker if you are pushing your subs to their limit or your amp can't reach the SPL you want and you need to limit the lower frequencies that really suck up the power.
08-26-11, 06:40 AM
#28
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Well the sub is definitely being pushed to it's limit. I'm running it at a pretty low volume level right now so I don't kill it, but you can definitely hear that it's not happy.
Here's my build thread showing what head unit and amp I'm running.
https://www.clublexus.com/forums/ls4...ml#post6589211
Here's my build thread showing what head unit and amp I'm running.
https://www.clublexus.com/forums/ls4...ml#post6589211
08-28-11, 12:43 PM
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Please let us know how it sounds when your sub arrives. I want to get the 10 inch Pioneer shallow mount and wondering how it will fair in the stock sub location of a 2GS
08-30-11, 11:27 AM
#30
If you're still looking for a woofer to run IB take a look at Image Dynamics. All of their woofers are capable of running IB. If you're sticking with an 8 then the ID series will be a good choice. I've used these guys IB before and have had great results. Also look at the IDQ10 if you are willing to step up to a 10 inch woofer