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8 inch woofer?

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How many people like 8" woofers?

I have drawn up a design for an 8" subwoofer as a fun side-project but I find myself liking the design more and more as I look it over!

This is what I came up with, wondering who would be interested:

FS = 23.6 Hz

Qms = 2.55

Qes = 0.350

Qts = 0.308

VAS = 21.2 L

RE = 3.32 Ohms

Z = 4 ohms

Le = 1.668 mH

BL = 12.73 N/A

Mms = 113.46 g

XMAX = 12.2 mm one-way by 70% BL method

Xmech = 18 mm (the coil will hit the back plate at 18mm)

Power Handling = 200 watts RMS

Sealed Box Specs:

0.185 ft^3

0.707 Qts Alignment

F3 = 55 Hz

Ported Box Specs:

0.50 ft^3

Tuning = 30 Hz

F3 = 28 Hz

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This driver would also make a pretty solid midbass driver up to 100 - 200 Hz or so :)

It would be fairly shallow... I don't have an exact figure as I'm not 100% sure the total depth on the basket. The motor is only 45mm tall (right about 1.75").

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UPDATE 3-6-08:

Little bit of FAQ of sorts:

1) Will the parameters be the same for the production mode?

The parameters are different. I didn't make any changes to the motor or coil since then but I gave it a stiffer surround as the original surround was just mushy and I hated it... that raised the Qts to the mid 0.4s and the Fs to the 30s. The VAS also decreased so the enclosure requirements and response are actually pretty similar. Since the only one I have "final" was assembled by me and I am not as accurate with glue (extra mass) my measurements won't be dead on. I'll get exact, broken in, specs when the drivers come in.

2) What does this compare to?

I'd say it would compare well to the Tang-Band 8" but with more low-end output, especially sealed. It also has better thermal power handling due to having basket windows and a directly vented gap. With Sean's help we did burps on it with 800 watts and he still runs the proto daily with around 400-watts in a tiny bandpass box.

3) How high do they extend?

They will pretty easily reach 100 - 200 Hz, perhaps as high as 500 Hz inductance-wise but there are probably dust-cap breakups around that area.

4) So what is the final depth?

4.25"

5) How much power do they REALLY handle?

200-watts is very conservative. This is a 4-layer copper winding coil with an aluminum former -- the motor has a pole vent and direct gap vents, combined with spider plateau vents on the basket. Needless to say it has some real thermal potential. In all but the smallest box requirements 200-watts will suffice to sound good, but I would suggest having a 300-400 watt amp "on tap" for the smallest recommended sizes.

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You have me at midbass, but not at subwoofer.

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You have me at midbass, but not at subwoofer.

I've got a proto coming in just to see it :)

I'll see how it does.

Best part is I would be able to offer it at a really great price... I considered building them and selling them direct as a "specialty" item as I'm sure that 99% of my dealers will never sell an 8" woofer.

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It would give you a reason to off those Kickers in your Honda then too :)

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It would give you a reason to off those Kickers in your Honda then too :)

Don't worry, I've got something in the works to get rid of those... oops... did I say that out loud? :)

I can't take em' much longer... they sound pretty good but are fatiguing as can be. I can't listen to them loud at all... after installing some Seas midbass / midrange and an LPG tweeter in a friends car (awesome, by the way) these defiantly have to go!

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I think the LPG can even be fatiguing, I can't imagine how much "fun" those SS's would be. :D I will add though that everytime I hear an active 3 way with a nice 8, it makes me want to re-do my setup. Having Scott visit lately has again reiterated to me that I should have just really jumped into the truck instead of trying to do it on a budget. Not that my 2way doesn't put out, in fact I like it better than any passive 3 way I have ever heard in a car but you just can't replace the 8" midbass love you get from having a meaty driver. I look forward to hearing more as you get the proto back.

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I think the LPG can even be fatiguing, I can't imagine how much "fun" those SS's would be. :D I will add though that everytime I hear an active 3 way with a nice 8, it makes me want to re-do my setup. Having Scott visit lately has again reiterated to me that I should have just really jumped into the truck instead of trying to do it on a budget. Not that my 2way doesn't put out, in fact I like it better than any passive 3 way I have ever heard in a car but you just can't replace the 8" midbass love you get from having a meaty driver. I look forward to hearing more as you get the proto back.

I had to tame the LPGs to get them just right, but with a few hours of EQ work... I didn't experience any ear fatigue to speak of at incredibly loud volumes in his car! Very impressive for me as my ears are pretty sensitive to harsh and fatiguing tweeters. Even used the aluminum dome LPGs in there... relatively off-axis in the A-Pillars and I did EQ separate left to right (right is more on axis with the driver). It's phenomenal, really :)

I simply can't get the SS drivers right... fatiguing no matter what I do and I have a 3Sixty.2 for processing and active crossover ability to boot. They sound quite good @ low volumes but just wear on my ears rapidly when turned up.

If I can figure out how to get an 8" driver in my door and still get the panel back on, I'll do it! I already have my window blocked up so that is no problem -- my concern is the metal bar behind the speaker hole and getting the panel back on. Not trying to hack up my car too much at this time... the other item in the works should do very well for midbass without resorting to an 8" driver.

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I actually didn't have any troubles until I started processing the response to help out the stage. In the process it made the LPG's a bit spitty and fatiguing, but the cure is to give up stage or even better redo the whole damn install in the right locations instead of using t/a and eq as a bandaid. The bandaid is easy to put on though.

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I actually didn't have any troubles until I started processing the response to help out the stage. In the process it made the LPG's a bit spitty and fatiguing, but the cure is to give up stage or even better redo the whole damn install in the right locations instead of using t/a and eq as a bandaid. The bandaid is easy to put on though.

I usually worry about stage second in my cars. I don't compete in SQ so it's okay :) I prefer mild or no T/A even if stage is off a bit. You are right, it does sound funny with too much processing and T/A going on! As long as I get a good sounding response and a reasonable stage I'm good to go.

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I constantly fidget, but that is half the fun. :D

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Its something to consider, I think SSA would sell a few 8's.

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I'd run them in the apartment.

Dual 8" woofers in a TL per channel...hmmm...

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I would think that if they were priced at around the same as the re8 pre buyout, then you could sell 1 or 2. I know i would buy a couple. :popcorn:

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If they were priced around the same as the RE8, but sounded good, they'd be no reason not to buy them :D

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If they were priced around the same as the RE8, but sounded good, they'd be no reason not to buy them :D

What was the RE8 going for ?

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I believe the 8 was like $50 or $55 plus shipping. It seemed like everyone with a reg cab truck run them for a while, and bought like 4 at a time.

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*ponders*

I may be able to match that price... this woofer is pretty well comparable to the RE-8, although, it has WAY less moving mass than the RE-8 does.

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I bought a bunch of the RE8's when they were $43 a piece.

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Cool, i would be down for some 8's. Always had a soft spot in my heart for 8's :) . I would deffintly be down for ordering a bunch. Coil Size?

Corey

Edited by SundownAudioNY

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The specs seem alot like the tang band 740 8"s. I just put 2 in my maxima off a jbl bp600 in about 1.5@35 really impressed with the two tang band 8's. I've always loved the way 8"s sound and have never had a problem getting them loud.. I'd be interested to see how the SD 8's compare...

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Sure does look alot like the TB T/S specs, huh? :) Didn't notice that before.

I know mine will look nicer *laughs*

Shooting for better motor cooling as well.

We'll see how the proto pans out. I might have to work on it some more but I'm thinking I like the idea.

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James would finally be able to offer a decent upgrade for all the titan owners with the RF system that just want under front seat subs.

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