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Old 25th September 2012, 02:22 PM   #31
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So, Arno, what have you done in the last 3 years?

Since my last post I have acquired a '96 Mazda Miata so I'm in the same "limited space" position you are when it comes to bass. I had considered building a vented enclosure for the package tray behind the seats using two TB W6-1139 but each would need ~.88cuft net volume plus a rather large displacement vent/port.

I gave in to technology and bought two Elemental Designs E3.8 8" subwoofers. They only need ~.35cuft each sealed. I may need only one since the Miata is so small and I'm not a basshead. I'm amazed at how small enclosures can be these days for sealed subwoofers.
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Old 25th September 2012, 04:18 PM   #32
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Originally Posted by Brian Steele View Post
They might have been doing 126dB when given a 44 Hz signal, but are you sure that the output was 44 Hz and not a whole lot of distortion?
Quote:
Originally Posted by ThyDntWntMusic View Post
...no? it was 44hz.
If you measured with a dB meter, you are measuring the combination of harmonics and fundamental.
If you measured with an RTA, you will see what the harmonic content is in relationship to the fundamental. It is not at all unusual for the harmonics to exceed the fundamental when driven hard, and since the first harmonic is an octave, it sounds quite similar to the fundamental.
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Old 25th September 2012, 08:33 PM   #33
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what exactly are you trying to argue? it WAS 44Hz at 126dB from two 4inch mids...

measurements were on a termlab SPL meter, they don't even register anything above 80Hz.
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Old 26th September 2012, 08:25 AM   #34
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Quote:
Originally Posted by ThyDntWntMusic View Post
what exactly are you trying to argue? it WAS 44Hz at 126dB from two 4inch mids...

measurements were on a termlab SPL meter, they don't even register anything above 80Hz.
Oh.

Please show your "termlab RTA" results, the link you posted clearly shows a 46 Hz fundamental at 159 dB with a 92 Hz harmonic at 138 dB.

To state the obvious, Termlab registers above 80 Hz, though the SPL reading would be a combination of whatever is loudest and the lesser output below or above the fundamental frequency used.

A -21 dB first harmonic at a 159 dB level would be outstanding, only 8.91% distortion.

I'll not hold my breath waiting for your Termlab RTA reports of 126dB at 44Hz from two 4 inch mids.
Then again, you did not state the measurement distance or size of the room (car?), so anything is possible, especially in a closed small chamber.

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Old 26th September 2012, 09:14 PM   #35
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in car.

folded horn.

126dB, 44Hz, no pics because this was years ago now.

and, what link I posted? :/
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Old 26th September 2012, 09:30 PM   #36
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Quote:
Originally Posted by ThyDntWntMusic View Post
in car.

folded horn.

126dB, 44Hz, no pics because this was years ago now.

and, what link I posted? :/
Sorry, I looked up Termlab, the picture was from their site, not a link from you. As you can see, the Termlab reads above 80 Hz, so the 126 dB could easily have been a combination of 44, 88 and 132 (and even higher harmonics) Hz, no way of knowing without an RTA picture what made up the 126 dB.
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Old 26th September 2012, 10:36 PM   #37
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Quote:
Originally Posted by 901Fixer View Post
So, Arno, what have you done in the last 3 years?

Since my last post I have acquired a '96 Mazda Miata so I'm in the same "limited space" position you are when it comes to bass. I had considered building a vented enclosure for the package tray behind the seats using two TB W6-1139 but each would need ~.88cuft net volume plus a rather large displacement vent/port.

I gave in to technology and bought two Elemental Designs E3.8 8" subwoofers. They only need ~.35cuft each sealed. I may need only one since the Miata is so small and I'm not a basshead. I'm amazed at how small enclosures can be these days for sealed subwoofers.
There's a dude on Diyma that's running dual fifteens in infinite baffle in a Honda S2000.
Might be worth a look. Infinite baffle is a very attractive option in the car, due to space limitations.
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Old 27th September 2012, 07:06 AM   #38
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Quote:
Originally Posted by weltersys View Post
Sorry, I looked up Termlab, the picture was from their site, not a link from you. As you can see, the Termlab reads above 80 Hz, so the 126 dB could easily have been a combination of 44, 88 and 132 (and even higher harmonics) Hz, no way of knowing without an RTA picture what made up the 126 dB.
you should have a play with a termlab
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