| Infinity buff |
Seems like I read somewhere, (probably here) that car speakers (Woofers) are not usualy suitable for home use. Is this true, and if so why?
I was checking out Infinities line of VQ car woofers and they seem like a DIY's, dream come true because they have variable Q. |
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| clem_o |
Car subs usually have a fairly high Qts, as they are designed to work into a large (almost infinite) baffle volume. Trying to use them in the house translates to very large boxes.
I am not familiar with the Infinity VQ series, but if they are, as you say, variable Q, then there shouldn't really be a reason why they can't be employed for home use... |
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| Eva |
| There are both low-Qts and high-Qts drivers. It's just a matter of finding the driver with the right parameters. Try to avoid fancy-looking stuff as it has usually the worst performance. |
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| zobsky |
| quote: | Originally posted by Infinity buff
Seems like I read somewhere, (probably here) that car speakers (Woofers) are not usualy suitable for home use. Is this true, and if so why?
I was checking out Infinities line of VQ car woofers and they seem like a DIY's, dream come true because they have variable Q. |
any dual coil woofer with a potentiometer or resistor across one coil can be used as a "variable q" transducer. |
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| soloxp |
| I have a kicker Comp 15" in a 4.3cuft box. The damn thing will drop some deep bass. I just have a PE 250w amp. Soon to be a 51" tall sonotube. I say go for it and have fun. |
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| [LMS]007 |
| quote: | Originally posted by Infinity buff
Seems like I read somewhere, (probably here) that car speakers (Woofers) are not usualy suitable for home use. Is this true, and if so why?
I was checking out Infinities line of VQ car woofers and they seem like a DIY's, dream come true because they have variable Q. |
Completely false, many car audio subwoofers are designed for competition, huge surrounds, big displacement and they can compromise sound quality. They are designed with dual and quad voice coils so you can get the dcr to 1ohm or lower so you can get more power into it, if your amp can take it. Home subwoofers are typically 4ohms now. |
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| Infinity buff |
Seems like there is a range of opinion. The main reason I am interested, is that I purchased a pair of Vifa 10" model # MA26wr09-04, on Ebay for $200. I bought them because the specs looked good for what I want, i.e they will play low in a 1.5cu ft box. I didn't get around to noticing that they are car speakers, untill I had already paid for them-oops! However, the specs look as good as many home speakers- except the sensativity is only 83.3 db. Hopefully they will work good- if not, off to ebay they will go once again.
Clearly, not all car speakers are suitable for home, but it sounds like some, probably are, (hopefully the ones I bought ARE!) I will update this post when I get them installed and let everyone know.
About the Infinity VQ series: They actualy use metal inserts into the magnets to vary the Q. The link is below for anyone interested.
http://infinitysystems.com/caraudio...ry.aspx?Ser=KPE |
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| Vivek |
| What would a decent Qts be for a car subwoofer which could be used for home theatre? |
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| zobsky |
| quote: | Originally posted by Vivek
What would a decent Qts be for a car subwoofer which could be used for home theatre? |
assuming you're porting it for maximum low end, ..i'd say 0.3 - 0.4 something, .... with a low Fs.
look at the specs for the adire shiva 12"(or it's dayton DVC clone) for an example of what specs a HT sub driver could have. |
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| Destroyer OS. |
Infinity and Kicker are not musical subwoofers, I would not use either in any thing personally. Infinitiy over rates their Perfect series, they are nothing amazing, just over priced.
Sealed enclosures will probably not be very big, but ported are likely to be really big. |
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| Vivek |
| The DIY community in India is very small. Since the demand is small it is difficult to get good sub drivers. I was looking at using the JBL car subs for HT use. JBL, Infinity, Sony, Kicker, Alpine, Blau, Polk Audio stuff is freely available. |
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| Thijs666 |
Quite some time ago, about 10 years, I stumbled upon a JBL GTI 1200 Car-subwoofer. It was on sale, so I decided to play with WinISD a bit. What I then achieved, made me buy one instantly. (for WinISD-designers: try a 6th order, front room 31 L, tuning 50Hz, back room 171 L, tuning 22Hz, values are 'or so'). I got a straight line from 22 to 50 Hz:bigeyes: ...
The first cabinet I made stunned me, so I bought a second woofer:D . Okay, I know these beasts can handle 600W RMS (at which I got frightened, 'cause I then lived with my parents in an old house), but the sensitivity is 93 dB/W. I even got to measure the floor resonance with these things:eek: , about 14 Hz, but that was quite frightening on the first floor.
Anyway, I still own these things, though I must say they are rather slow (but that's because of the 6th order and low tunings I guess) and I recently got the opportunity to measure them. I borrowed a Neutrik amplitude-measurement system incl. mic, but the readings I got were different then WinISD predicted. The port of the front housing played from 28 to 50 Hz, and the rear port played from 20Hz straight to 31Hz (Neutrik couldn't measure <20Hz), BUT sensitivity was about 6 dB lower than the front port. I suspect I used too much stuffing:( .
My point: it can't hurt to try what is available. |
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| Vivek |
| Thijs666, that was quite inspiring. Thank you. Now, the current model is the JBL 1202D. How will a ported box work out? |
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| Destroyer OS. |
| What about Focal? They are pretty big on car audio. |
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| Infinity buff |
| I installed the Vifa's I bought on ebay. They sound very smooth and musical- a great improvement over the stock woofers. They don't seem to play as loud as the originals though. Partly I think that is because they have less distortion, but also they are less efficient. Fortunately my speakers have adjustments for the mids and highs so I can get them to blend pretty well. Coupled with my powered sub they sound increadable. So in this case, the care speakers are a good fit. |
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| Vivek |
| I might be able to find Focal. It could take a lot of searching though. |
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| goldyrathore |
Hi Vivek,
Focal is available @ Car shringar.
Hope this helps.
Goldy |
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| Vivek |
| Are they car subs or home audio subs? How much do they cost? |
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| simon5 |
| quote: | Originally posted by Vivek
The DIY community in India is very small. Since the demand is small it is difficult to get good sub drivers. I was looking at using the JBL car subs for HT use. JBL, Infinity, Sony, Kicker, Alpine, Blau, Polk Audio stuff is freely available. |
If you can find some T/S parameters about the stuff you can have I could help you.
You can probably discard Sony already.
Try to find Vas, Qts, Fs and Xmax. |
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| weng |
| quote: | Originally posted by simon5
If you can find some T/S parameters about the stuff you can have I could help you.
You can probably discard Sony already.
Try to find Vas, Qts, Fs and Xmax. |
simon5,
can u pls also help me decide if my car sub is suitable for a home sub? the sub driver is a 12" JL Audio (w3v2 model)- 2 ohms dual voice coil. below are the parameters u required:
Vas = 3.65 ft3 (103.4 liters)
Qts = 0.449
Fs = 24.3 hz
Xmax = 0.513 in (13.0 mm)
cheers,
weng
vivek...sorry for the tread jack |
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| simon5 |
Yes it's suitable for a home subwoofer.
Sealed will work and ported will work too, but ported will need a medium to large enclosure, may be better to go with passive radiators. |
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| weng |
| quote: | Originally posted by simon5
Yes it's suitable for a home subwoofer.
Sealed will work and ported will work too, but ported will need a medium to large enclosure, may be better to go with passive radiators. |
thanks simon5.
it is hooked up right now in my car powered by an old school rockford amp. the enclosure is 2.25 cu ft, slot ported tuned to 28 hz as per JL specs.
now i am confident to buy a plate amp. plate amps are very rare in the philippines. i have to get mine from the US or get it from a diy'er who's selling a decent one though. |
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| Vivek |
Simon, these are the parameters for the JBL 1202D:
Vas=98L
Qts=0.44
Fs=23.50Hz
Xmax=12.5mm
Weng, it's okay. I too did the same. :D |
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| simon5 |
| quote: | Originally posted by weng
it is hooked up right now in my car powered by an old school rockford amp. the enclosure is 2.25 cu ft, slot ported tuned to 28 hz as per JL specs. |
If you're going to listen movies with it, I would build a larger enclosure tuned lower, but you could start with the enclosure you have now to see if it's ok for you already.
With a larger enclosure, you lose some output but gain more very deep bass. |
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| simon5 |
| quote: | Originally posted by Vivek
Simon, these are the parameters for the JBL 1202D:
Vas=98L
Qts=0.44
Fs=23.50Hz
Xmax=12.5mm
Weng, it's okay. I too did the same. :D |
The JBL 1202D will work in a ported box, no problems. |
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| Vivek |
| The question is whether it will work well in a home theatre setup? |
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| simon5 |
| Yes, no problems with it, especially if you can build a large box. |
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| Vivek |
| How about trying something more interesting like a dipole or push push with two of them? |
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| simon5 |
| Hmmm they are probably not good drivers for dipole use but for push push there's no problems. |
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| Vivek |
Let's see how it goes. Thanks for your help Simon.
Cheers,
Vivek |
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| wiredcharlie |
I used a 10" JBL GT4 http://www.motor-world.co.uk/show_prod.php?prod_id=5449 to extend the range of my PMC DB1+s. The box is undersized to produce a system resonance of 51Hz and is then equalized using a double integrator as per http://sound.westhost.com/project48.htm. The internal volume is only 18.1 litres less the basket. The undersized box / double integrator is subject to a patent. http://www.audioannals.com/04481662...kersham-txt.htm The full document is available if you use "DjVu" http://www.djvuzone.org/download/index.html
(My understanding is that patents are effective for 20 years, so this one is no longer active).
This is a novel and (apart from the amplification) inexpensive way to extend the range of your main speakers. The double integrator equalizer means that the speaker needs 12db more power at 25Hz than at 50Hz, but 12dB less power at 100Hz than at 50Hz. This is a narrow band of operation so power requirements are not as great as you might first suspect.
I don't see any disadvantage in using a car sub for this project!
Tony
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| FE3T |
This remind me of a rather perverted idea i struggle too lay off my mind.
I have 2 of these:
http://www.rockfordfosgate.com/rfte.../RFR2212-TS.pdf
and 2 of these:
http://www.rockfordfosgate.com/rfte.../RFR2215-TS.pdf
A pair of midwoofer called Macrom Integra 224W (8,5")
and finally a pair of Morel 28mm tweets.
The idea are as following:
15" in separate boxes. 160L tuned to 23 hz (up too 50hz)
12" used as low midbass in 35L sealed (50-120hz)
8,5" in 25L sealed (from 120-3000hz
and the tweets from there and up.
Bi or maybe even triamped (eventually with hipower Plate amps on the woofers)
Maybe a tad expensive too build, but migth be worth it ;)
Or what?
Attached pic are just a rough drawing, done with paint |
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| simon5 |
Since you want to put the speaker cabinet on top of the subwoofer cabinet, you could discard the 12" I guess.
Nice project, I don't know if the SQ would be good, but it would be a really cool and loud project. |
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| Vivek |
Hi again, I just got a couple of Infinity Reference 1230 12 inchers.
VOICE COIL DC RESISTANCE: REVC (OHMS) . . . . . . 3.40
BL (TM) . . . . . . . . 14.63
VAS (LITERS) . . . . . 78.50
CMS (µM/N) . . . . 195.40
MMS (GRAMS). . . . 174.21
MMD (GRAMS) . . . 167.15
FS (HZ) . . . . . . . . 27.27
QMS . . . . . . . . . . . 6.14
QES . . . . . . . . . . . . 0.47
QTS . . . . . . . . . . . . 0.44
XMAX (MM) . . . . . . 12.25
What can I do with them for a home theatre subwoofer? |
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| bobo1on1 |
I have got a US blaster usb-2100, seen in most stores for 419 euro, I bought in on sale for 60 euro's (and 10 euro's shipping :mad: ).
Check it out here: http://www.xs4all.nl/~loosen/us%20blaster%20subwoofer/
It's designed to play in a ported box of about 50 liter, in which it can have an f3 of about 32 hertz.
Closed is absolutely horrible because of the low vas.
I don't care if it's a car woofer or not, for 419 euro's it just can't be bad. |
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| simon5 |
| quote: | Originally posted by Vivek
Hi again, I just got a couple of Infinity Reference 1230 12 inchers.
VOICE COIL DC RESISTANCE: REVC (OHMS) . . . . . . 3.40
BL (TM) . . . . . . . . 14.63
VAS (LITERS) . . . . . 78.50
CMS (µM/N) . . . . 195.40
MMS (GRAMS). . . . 174.21
MMD (GRAMS) . . . 167.15
FS (HZ) . . . . . . . . 27.27
QMS . . . . . . . . . . . 6.14
QES . . . . . . . . . . . . 0.47
QTS . . . . . . . . . . . . 0.44
XMAX (MM) . . . . . . 12.25
What can I do with them for a home theatre subwoofer? |
Looks like nice drivers for a sealed box. |
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| Vivek |
Exactly what I was thinking. A sealed box of about 70L and then equalise the bottom end.
Tony, do you get enough SPL for HT use?
Also, tell me one thing. Are commercial subwoofers all equalised since most cabinets are rather small.
bobo1on1, nice looking sub driver there. |
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| Ranthum |
| Sorry to jump in, but I was wondering how my ID MAX 12 would perform in my HT? I don't have the specs ATM, but i think they're in WinISD. |
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| bobo1on1 |
| It would do pretty darn good, -3db at 27 hertz. |
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