Sub enclosures off Ebay
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Sub enclosures off Ebay
Has anyone bought a box off of Ebay. I was looking at one from soundoffaudio. They said the box was made of 5/8" MDF. Do you think this is a safe buy, I was planning on running 2 JL Audio W-3s.
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(2) JL 10W3V2 - of what voice coil resistance? They actually come in three difference coil resistances with slightly different sounds.
Using the 4 ohm's Thiel-Small parameters and a box volume of .6 I get a Qtc of 1.4 which in my opinion is too high - you'll a big 4-5 dB bump around 110 hz which will sound "boomy".
The 2 ohm driver has a bit different Thiel-Small parameters and I get a more pleasing Qtc of 1.2 with the same box volume. Your -3 dB point will be 55 Hz.
Using the 4 ohm's Thiel-Small parameters and a box volume of .6 I get a Qtc of 1.4 which in my opinion is too high - you'll a big 4-5 dB bump around 110 hz which will sound "boomy".
The 2 ohm driver has a bit different Thiel-Small parameters and I get a more pleasing Qtc of 1.2 with the same box volume. Your -3 dB point will be 55 Hz.
#4
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PS: If you've got the extra $70 of scratch per woofer have a look at the JL 10W6v2 which are designed for small box enclosures.
Using two of these guys I get a near perfect Qts of 1.1 and a -3 dB point of 48 Hz. The response is going to be much flatter.
I've got the e-bay box and I'm currently shopping woofers and the 10W6v2 is my current choice.
Using two of these guys I get a near perfect Qts of 1.1 and a -3 dB point of 48 Hz. The response is going to be much flatter.
I've got the e-bay box and I'm currently shopping woofers and the 10W6v2 is my current choice.
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Originally Posted by Paul350Z
(2) JL 10W3V2 - of what voice coil resistance? They actually come in three difference coil resistances with slightly different sounds.
Using the 4 ohm's Thiel-Small parameters and a box volume of .6 I get a Qtc of 1.4 which in my opinion is too high - you'll a big 4-5 dB bump around 110 hz which will sound "boomy".
The 2 ohm driver has a bit different Thiel-Small parameters and I get a more pleasing Qtc of 1.2 with the same box volume. Your -3 dB point will be 55 Hz.
Using the 4 ohm's Thiel-Small parameters and a box volume of .6 I get a Qtc of 1.4 which in my opinion is too high - you'll a big 4-5 dB bump around 110 hz which will sound "boomy".
The 2 ohm driver has a bit different Thiel-Small parameters and I get a more pleasing Qtc of 1.2 with the same box volume. Your -3 dB point will be 55 Hz.
#6
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It's really simple
Every model of woofer has a different flavor which is caused by various electro-mechanical parameters. The design engineers alter these with a certain sized speaker box in mind - and even ported or non-ported boxes.
Some speakers are designed to have a hole of a certain dimention with a tube of a certain lenght put into them, sometimes this is a slot rather than a tube.
Using the Thiel-Small parameters and a forumla you can reverse engineer the size of the box the engineer designed the speaker for. Some manufactures say that they're speaker is designed for a box of between 0.5 and 1.0 cubic feet. Putting that speaker in a box 0.5 and then 1.0 cubic feet will give very different sounds.
Qtc is the total system resonance of a speaker system.
The Qtc will give you an estimate of the lower slope of the woofer's response will look like. With a lower one like 0.707 you'll get a gentle falling slope with the F3 - the point where the woofer's output is down 3 dB at the lowest possible point. Higher ones around 1.0 to 1.1 give a bit of an artificial boost which can be heard as a stronger base. Still higher ones of 1.2 and above will give a very high boost to the bass frequencies.
Any Qtc number above or below 0.707 will cause the F3 to be higher.
Here's a ton of box design formulas:
http://www.carstereo.com/help/Articles.cfm
Note the "perfect" Qtc of 0.707 in black and the one of 1.0-1.1 that would be between the one in red and the one in dark purple that I'm aiming for in my system. Closer to one is better ... I'd be happy with 0.9 if I could find a pair of woofers that would do that in the tiny 0.66 cu.ft. box.
Every model of woofer has a different flavor which is caused by various electro-mechanical parameters. The design engineers alter these with a certain sized speaker box in mind - and even ported or non-ported boxes.
Some speakers are designed to have a hole of a certain dimention with a tube of a certain lenght put into them, sometimes this is a slot rather than a tube.
Using the Thiel-Small parameters and a forumla you can reverse engineer the size of the box the engineer designed the speaker for. Some manufactures say that they're speaker is designed for a box of between 0.5 and 1.0 cubic feet. Putting that speaker in a box 0.5 and then 1.0 cubic feet will give very different sounds.
Qtc is the total system resonance of a speaker system.
The Qtc will give you an estimate of the lower slope of the woofer's response will look like. With a lower one like 0.707 you'll get a gentle falling slope with the F3 - the point where the woofer's output is down 3 dB at the lowest possible point. Higher ones around 1.0 to 1.1 give a bit of an artificial boost which can be heard as a stronger base. Still higher ones of 1.2 and above will give a very high boost to the bass frequencies.
Any Qtc number above or below 0.707 will cause the F3 to be higher.
Here's a ton of box design formulas:
http://www.carstereo.com/help/Articles.cfm
Note the "perfect" Qtc of 0.707 in black and the one of 1.0-1.1 that would be between the one in red and the one in dark purple that I'm aiming for in my system. Closer to one is better ... I'd be happy with 0.9 if I could find a pair of woofers that would do that in the tiny 0.66 cu.ft. box.
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I bought one from someone that got it from Ebay and it is not perfect it doesn't fit 100 percent under the strut bar, if you push it in to fit flush in the rear it sticks out in the front side of the bar and it stays in place during normal driving but do some hard accels and it slides back out from tunder the strut bar, not sure if that is due to harder accel with the TT and it will be fine with an NA.
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#8
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Originally Posted by westpak
I bought one from someone that got it from Ebay and it is not perfect it doesn't fit 100 percent under the strut bar, if you push it in to fit flush in the rear it sticks out in the front side of the bar and it stays in place during normal driving but do some hard accels and it slides back out from tunder the strut bar, not sure if that is due to harder accel with the TT and it will be fine with an NA.
I was debating on recessing "T" nuts into the bottom of the box. "T" nuts sink into wood and have a threaded screw bolt. Running these up though the bottom would allow me to tread screws down from the inside of the box to a waiting thin steel plate which would sit on, and protect, the carpet. Tightening the screws would cause the bottom of the box to push down on the steel plate and push up jamming the top of the box into the strut.
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Originally Posted by onii
dont buy from 350viper. i ordered it 2 weeks ago..the idiot shipped it to the wrong address, and never replies to his emails. im still waiting.
#11
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If you got it from Mike at Zenclosures my experence was great - quick response, follow-up upon payment and mailing. They come from Florida I think and it's a heavy box so it took a full week to make it here to California.
It's possible with summer break that the guy is flooded with orders ... still he needs to communicate issues in advance.
It's possible with summer break that the guy is flooded with orders ... still he needs to communicate issues in advance.
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Originally Posted by Paul350Z
If you got it from Mike at Zenclosures my experence was great - quick response, follow-up upon payment and mailing. They come from Florida I think and it's a heavy box so it took a full week to make it here to California.
It's possible with summer break that the guy is flooded with orders ... still he needs to communicate issues in advance.
It's possible with summer break that the guy is flooded with orders ... still he needs to communicate issues in advance.
When I buy something on the internet, or anywhere, I want it now. I keep this in mind with every order, getting it shipped asap.
thanks mike
ZEnclosures
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i shoulda ordered mine off u mike. i still havent gotten my box, and he hasnt replied to any emails. skittlez...has he emailed u? ive sent him an email like everyday since last week and still nothin...almost 3 weeks for me too.
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Originally Posted by mlg9770
Sorry you guys are having problems getting your boxes, but I just wanted to clarify it wasn't ordered from me. I ship within 48 hours, and if I can't I 2nd day air it out of my own pocket. I just don't want people confusing me for others they are having problems with.
When I buy something on the internet, or anywhere, I want it now. I keep this in mind with every order, getting it shipped asap.
thanks mike
ZEnclosures
When I buy something on the internet, or anywhere, I want it now. I keep this in mind with every order, getting it shipped asap.
thanks mike
ZEnclosures
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Originally Posted by onii
i shoulda ordered mine off u mike. i still havent gotten my box, and he hasnt replied to any emails. skittlez...has he emailed u? ive sent him an email like everyday since last week and still nothin...almost 3 weeks for me too.
i emailed so many times. i only got a response when i emailed him directly from ebay. this guy really sucks. he told me he needed to get some more supplies in to finish some boxes and that mine would ship on the 27th. he won't reply any more....
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i ordered my trunk corner box from mike.
it was very fast shipping. packed really well and i asked him questions after i installed my sub, he replied my email in very short time.
it was very good price and high quality and service was awesome. highly recommend mike's box.
it was very fast shipping. packed really well and i asked him questions after i installed my sub, he replied my email in very short time.
it was very good price and high quality and service was awesome. highly recommend mike's box.