# 8" subwoofer



## nutzie (Jul 13, 2008)

Hi

I have the DLS 1070 playing on a genesis four channel. It plays only on lowpass for the bass. One of them died so i'm searching something new. The bass of the dls 1070 was very very good.

I need my truckspace so i need a subwoofer in a small closed box, Max 15 L. Probably i gonna install one 8" woofer.

Could the DLS OA8 do the job?

Specs of the genesis four channel: bridged @4 ohm +-250 RMS.

I want a nice, clean bassound. More SQ. I listen to top 40 music and dance.

Or are there any other suggestions for a 8" subwoofer that fits my requirements.

Sorry for my bad english.


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## Candisa (Sep 15, 2007)

Why don't you just stick with the principle you are already using? I assume those 1070's are hanging in the rear deck, using 2 channels of that Four Channel?

Replace them with a pair of dedicated 8-10" subwoofers that are capable of playing infinite baffle, have a great sensitivity and don't need too much power.

I have a pair of oldskool Soundstream SS8's laying around, if you can find a pair of those, buy them! They have a low qts and vas, but they're perfectly capable of playing infinite baffle with about 100W each on them, subsonic filtered (a four channel has a high pass filter, don't turn it all the way down, use it as a subsonic!) at around 30Hz. It's useless to let any 8" subwoofer play lower than that (and if you find one that can do it properly, it won't do it in a 15liters sealed box or IB)...

greetz,
Isabelle


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## sqshoestring (Jun 19, 2007)

If there is any way you can do a pair of 10s IB, that is a nice setup for SQ with reasonable output. 8s just can't get it IB, even if you run a 10 into an 8" hole it will work better IMHO. Especially if you run more efficient sub IB, it needs to be larger diameter to get lower Fs. I have four 12s into my back seat, takes nearly no trunk room, on 400rms it can shake the car and will play 20hz. It actually a little too much for my use, can't even hear the music (highs) with them dialed up and highs are 4x70rms. Also some of the thin subs can do IB if you need to maximize space even more. If you're happy with 8s then one 12 or two 10s will do you well. I run four 12s primarily so it gets lower and still has some dB.


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## nutzie (Jul 13, 2008)

Candisa said:


> Why don't you just stick with the principle you are already using? I assume those 1070's are hanging in the rear deck, using 2 channels of that Four Channel?


Because it's difficult to find 2 * 8" subwoofers that can play free-air (hanging in the rear deck) and need max 100 RMS.

I can't believe that one subwoofer can't give me the same result as the 7*10speakers :s.? I thought that real subwoofers were better.

I had a time ago one 10 " subwoofer (x-ion) and it was to loud for me. No 10" more from me, i don't have the space for it, another reason why i have sold the sub.

So i thinka 8" can do the job..

Or i'm completely wrong?.


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## GlasSman (Nov 14, 2006)

I've used the IMAge Dynamics ID8 v.3 and they work nice IB in the rear deck.


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## Candisa (Sep 15, 2007)

There's no way a subwoofer can be 'too loud', you can always attenuate it, but some subwoofers don't play nice and tight at lower volumes, that's something completely different.

You probably mean the Audio-System X-ion? That are just worthless subs for SQ!
There are only 2 series of Audio-System I like: the Twister series (nice amps for the money) and the HX series (nice comps and subs). All the rest of their products, well, sorry but it sucks...

You're better off with a (pair of) sub(s) that can play too loud (you can attenuate them!), than subs that just can't do it...

How it sounds is something completely different, to have decent sound quality at all levels, you need a sensitive sub (one that doesn't only start to play when the volume is cranked all the way up) with a nice response and useable specs.

A pair of good 8" dedicated subwoofers in the rear deck *will* get lower than a pair of oval coaxials.
A pair of comparable 10" subs in the rear deck will only get even lower.

One 8" subwoofer that's happy with a very small enclosure really won't get lower and will take up more space...

There are plenty of 8" or 10" subwoofers out there that are capable of giving nice results with the power you're giving them, mounted IB.

greetz,
Isabelle


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## Lothar34 (Oct 6, 2006)

http://www.partsexpress.com/pe/pshowdetl.cfm?&Partnumber=264-854


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## mvw2 (Oct 2, 2005)

nutzie said:


> I can't believe that one subwoofer can't give me the same result as the 7*10speakers :s.? I thought that real subwoofers were better.


Understand the basic physics of sound reproduction.

A subwoofer and normal woofer are the same. Subwoofers are not "special." However, they are engineered with a different intent. Generally subwoofers have better low frequency sensitivity and higher excursion limits (xmax, xmech, xsus). This means they play lower more naturally and are capable of getting louder than a normal woofer.

8" subwoofer: 
-peak sensitivity: 60Hz - 400Hz (+/- 3dB)
-excursion: 10mm xmax, 15mm xmech
-thermal power handling: 300 watts rms
-sensitivity: 85dB (1w/1m)

8" woofer:
-peak sensitivity: 100Hz - 1.5kHz (+/- 3dB)
-excursion: 6mm xmax, 12mm xmech
-thermal power handling: 100 watts rms
-sensitivity: 90dB (1w/1m)

Almost all speakers are built the same way. The only difference is in the way they are geared. For example, the above two are simply made up but represent the differences. For example, the subwoofer is geared lower in frequency response. If both speakers were placed in a sealed or ported enclosure, the subwoofer will play lower. Because the subwoofer is geared lower, it will normally not play higher well, although, there are exceptions and depends on the intent of the engineers and what they wanted the speaker to do. The higher excursion of the subwoofer means it can play lower, louder than the normal woofer. However, say at 100Hz and up, both speakers can actually play about the same loud max. The regular woofer has a higher sensitivity, so it plays louder per watt. The subwoofer has a lower sensitivity and requires more wattage to get loud. You can only safely apply up to the rated rms wattage, and doing so, both end up about the same loud in higher frequencies. However, because the subwoofer has higher excursion capabilities, it can stay loud lower, so it does better for subwoofer use. The regular woofer stays loud higher, making it better for a midbass or even midrange use.

Now all speakers have limitation in output, either mechanically via xmax (linear) or xmech (mechanical) or thermally via rated rms wattage. At some point you will always hit these walls. For SQ, we generally consider xmax to be our upper limit in output in lower frequencies as this is the extent of linear motor travel. We can play louder but at decreased SQ. In higher frequencies, we generally run into the thermal limit before we do the excursion limit.

The subwoofer enclosure will have some influence on excursion use, a ported box especially. For smaller woofers and woofers with lower excursion, it is preferred to use a ported box. It simply requires less excursion use and extends the low frequency response out more before sensitivity rolls off. A sealed box will require more excursion use and the sensitivity rolls off earlier but shallower.

If we're talking 8" subs, and most having only about 10mm xmax, to really play low in the normal subwoofer range well (30Hz-100Hz), most 8" subs won't do it well in a sealed enclosure. They simply lack the low frequency sensitivity and available excursion to play low and loud. The overall capability goes up when in a ported box. You won't run out of excursion nearly as easy, and the port will bump up low end response. The downside of ported is that the box size is larger and the port will take up some additional volume as well. It may be difficult to get under 1 cu.ft. (30L).

I would also not suggest limiting yourself to an 8" woofer simply because you want a small box. It is possible to use a larger subwoofer, even upwards of a 12" in a small box, if it is geared for it. You ALWAYS have to move X amount of air to get Y loud at Z frequency. Playing a 40Hz tone at 100dB requires a specific amount of air movement. A larger woofer can do this more easily as it requires less excursion needs. The amount of air a woofer can move is a product of the cone area and excursion. It becomes pretty obvious that for low frequency use, the largest woofer you can fit should be used, or several smaller woofers that simply add up to a large cone area. In the end, you always have to be able to move the same amount of air. If you are trying to achieve 100dB at 40Hz, if you run out of excursion, you lose, if you hit the thermal limit, you lose. An 8" woofer may or may not be able to do it depending on how much output you want.


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## sqshoestring (Jun 19, 2007)

Look at this thread for some ideas on small subs, but don't expect them to blow you out of the car with low bass.
http://www.diymobileaudio.com/forum/showthread.php?p=495116#post495116

If you get the right subs in the right enclosure they can work, but be careful what you get. I would recommend IB myself if you can do it, can run larger sub(s) and takes near no room. Install might take some work but then all is good. If you can run twice or more the cone area IB as a box you will be happy and will take less room to do it.


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## nutzie (Jul 13, 2008)

sqshoestring said:


> Look at this thread for some ideas on small subs, but don't expect them to blow you out of the car with low bass.
> http://www.diymobileaudio.com/forum/showthread.php?p=495116#post495116
> 
> If you get the right subs in the right enclosure they can work, but be careful what you get. I would recommend IB myself if you can do it, can run larger sub(s) and takes near no room. Install might take some work but then all is good. If you can run twice or more the cone area IB as a box you will be happy and will take less room to do it.


That's exactly the thing i don't want: blow out of the car. a bas that i can feel a bit but no boem boem . thnx for the answers.

Has someone experience with the kicker c84?


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## ryanjorunner (Jun 19, 2008)

an image dynamics id8 is a great little sub. re8 as well


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## ryanjorunner (Jun 19, 2008)

oh and the ed 9kv.2


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## nutzie (Jul 13, 2008)

I bought a DD 1508. Fantastic sub!!


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## crosspug (Jul 14, 2008)

I'd be very interested in hearing how the little DD goes SQ wise..... I know they have the reputation for going loud for a little 8". But is it clear and crisp as well as decent output?? 

I've been looking at them for ages wondering to try or not to try!


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## nutzie (Jul 13, 2008)

crosspug said:


> I'd be very interested in hearing how the little DD goes SQ wise..... I know they have the reputation for going loud for a little 8". But is it clear and crisp as well as decent output??
> 
> I've been looking at them for ages wondering to try or not to try!



It play bridged on my genesis four channel and it get +- 260 RMS. It plays in a ported box. The sound is perfect for me. Really nice sound. Very clear, crisp and i can feel the sub! Try it, you wouldn't regret your choice!

Imagine what this sub can do with +-500/600 RMS on it .

I've readed a test about 5 different 8" subwoofers.:

Grading Scale will be 1 to 10. 1 being awful, 5 mediocre, and 10 being perfect.

_The areas being judged will be

1. Build Quality
2. Installation
3. Individual Genre Performance
4. Overall SQ
5. Overall SPL
6. LFE_

*Build Quality*

1. Critical Mass = 9 Well engineered, and attractive speaker
2. Elemental Designs = 8 Nicely put together speaker with great features
*3. Digital Designs = 8 High quality product*
4. Ascendant Audio =7 nicely built minus terminals
5. RE AUDIO = 4 basic design with some design shortcuts

*Installation*

*1. Digital Designs = 9 Mounting flange made best seal, screw cover also nice*
2. Elemetal Designs = 8 Push terminals DVC on same side for wiring options
3. Critical Mass = 6 Push terminals, didnt like screw hole size
4. RE AUDIO = 5 not a fan of the terminals
5. Ascendant Audio = 4 not the best seal, didnt like the terminals

*Classical Music*

*1. Digital Designs = 10 great definition, zero coloration*
2. Elemental Design = 9 accurate driver
3. Ascendant Audio = 8 great performance
4. Critical Mass = 6 some noted coloration
5. RE AUDIO = 3 poor performance

*Hip Hop Music*

*1. Digital Designs = 9 nice presentation*
2. Ascendant Audio = 8 great authority
3. Critical Mass = 7 nicely done
4. RE AUDIO = 5 great output with some noted coloration
5. Elemental Designs = 5 great sound, not allot of authority when pushed

*Jazz / R&B*

*1. Digital Designs = 9 great definition, authority, and control*
2. Critical Mass = 8 great performance
3. Elemental Designs = 7 Great sound quality, needs authority
4. Ascendant Audio = 6 was not able to handle both tracks equally well
5. RE AUDIO = 4 nice output, however very poor sound quality

*Rock Music*

1. Critical Mass = 7 nice performance
2. Ascendant Audio 7 = near perfect authority could have exhibited better extension
*3. Digital Design = 6 did not perform both tracks equally well*
5. Elemental Designs = 6 great sound quality, could have exhibited better authority
4. RE AUDIO = 6 did not perform both tracks equally well

*Overall SQ*

*1. Digital Designs = 9 near perfect*
2. Elemental Designs = 8 zero coloration in most genres
3. Ascendant Audio = 7 great capability
4. Critical Mass = 6 noted coloration in some genres
5. RE AUDIO = 3 poor sound quality

Score Tally
*Digital Designs = 72 points - Average Score 8*
Critical Mass = 65 points - Average Score 7.2
Ascendant Audio = 61 points - Average Score 6.7
Elemental Designs = 57 points - Average Score 6.3
RE AUDIO = 45 points - Average Score 5

The test was with the old model DD 1008, 1508 is even better.


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## crosspug (Jul 14, 2008)

Thanks for that reply, a great review you found!

Also good to know that its runs well off 260wrms as they seem to tend to be power hungry subs (DD in general). Now to find one below retail!

Jono


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## Oliver (Jun 25, 2007)

quote>

Subwoofer Review Excerpts 
Reviews of W7 Subwoofer Drivers:
“Simply put, the JL Audio 8W7 is the best damn 8-inch subwoofer ever made.” 

“...if you're looking for big audiophile sound in a package that requires a small amount of power and space, the JL Audio 8W7 isn't a good choice, it's the only choice.” 
– Paul Sonoda, Car Sound and Performance, June 2004 
quote>


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## nutzie (Jul 13, 2008)

a$$hole said:


> quote>
> 
> Subwoofer Review Excerpts
> Reviews of W7 Subwoofer Drivers:
> ...




I've readed reviews where people has heard the 8w7 and the DD 1508. All of them said that the DD blews the 8W7 away..


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## Oliver (Jun 25, 2007)

nutzie said:


> I've readed reviews where people has heard the 8w7 and the DD 1508. All of them said that the DD blews the 8W7 away..


http://www.audiogearreviews.com/reviews/subwoofers/review-JL_Audio_8W7.asp

quote>
to the cone and spider assemblies and accounts for the excellent control the 8W7 has over its massive linear excursion (1.5 inches peak to peak linear excursion to be exact). 
quote>

Blew them away as far as price, maybe 

quote>
Nine patents. In the world of “me too” engineering, JL Audio’s 8W7 has nine things unique enough to be granted patents. (Eight application patents and one design patent)
quote>


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