[kaigoss69]

Originally Posted by Technic

Morel ADMW SW 9"

http://www.janixworld.com/330xi/stereo/post/

I know about that installation but I always wondered about the enclosure size in relation to the driver's Qts value of .74 ... seems to be better suited for free-air.

[Technic]

Originally Posted by kaigoss69

I know about that installation but I always wondered about the enclosure size in relation to the driver's Qts value of .74 ... seems to be better suited for free-air.

This installation uses also the sill cavity.

[kaigoss69]

Originally Posted by VP Electricity

There are three possible reasons for less-than-stellar midbass from this location (in order of my projected probability):

1) The fact that it's under the flipping seat.
2) The location relative to the firewall/doors/roof/etc (destructive interference).

I've actually read over on DIY that that location, from an acoustical standpoint, may not be too bad at all, as long as you don't try to play voices.

Originally Posted by VP Electricity

For an infinite baffle to be effective (and not be part of an actual enclosure), there is some multiple (which I don't recall) which its area must be greater than the Sd (driver area). I don't think that multiple is possible under the seat.

Well, my knowledge is not that deep on this subject, but I thought the main purpose of the baffle was to separate the front waves from the back waves to avoid cancellation. If that is true, then take a look at the OEM enclosure and tell me that is not essentially the same thing - the back waves are contained within the enclosure and are allowed to resonate through the port, totally separated from the front waves. If you agree with that, then what is wrong with the concept I suggested earlier which in my mind is doing exactly what the OEM enclosure does, but with a larger volume and the capacity for a deeper driver.

[kaigoss69]

Originally Posted by Technic

This installation uses also the sill cavity.

Just curious, how do you know?

[Technic]

Originally Posted by kaigoss69

Just curious, how do you know?

There is a thread of this install in this forum...

[kmarei]

where does the sill port to?

[kaigoss69]

Originally Posted by kmarei

where does the sill port to?

The OEM enclosure is connected to the door sill via a "port". Some people have suggested that the door sill is sealed, so the entire enclosure is sealed as well. I don't buy this, not for one second (just consider the fact that a decent sealed box needs to be constructed from sturdy 5/8" thick MDF and sealed along the edges with silicone in order to be sturdy enough and air-tight, and then look at the OEM enclosure, the thickness of the plastic, the port connection "sealed" with weatherstripping, etc.). I believe the door sill is open (= not 100% air tight) to the outside and therefore the application would most closely resemble infinite baffle (IB), similar to an installation in a door or a rear deck, for example.

[kmarei]

Originally Posted by kaigoss69

The OEM enclosure is connected to the door sill via a "port". Some people have suggested that the door sill is sealed, so the entire enclosure is sealed as well. I don't buy this, not for one second (just consider the fact that a decent sealed box needs to be constructed from sturdy 5/8" thick MDF and sealed along the edges with silicone in order to be sturdy enough and air-tight, and then look at the OEM enclosure, the thickness of the plastic, the port connection "sealed" with weatherstripping, etc.). I believe the door sill is open (= not 100% air tight) to the outside and therefore the application would most closely resemble infinite baffle (IB), similar to an installation in a door or a rear deck, for example.

that's what i thought
but after i installed my SWS-8s and feeding them 120w RMS each
when i pump it up and stand outside the car with the doors closed
i don't hear the bass as clearly as i would if it was porting to the outside
so my guess was it was porting to the inside of the car
i read somewhere here, that it ports to where the seat belt comes out of the B pillar
but when i put my ear there i could not detect any sound

justr curious i guess

[kmarei]

Originally Posted by kaigoss69

a decent sealed box needs to be constructed from sturdy 5/8" thick MDF and sealed along the edges with silicone in order to be sturdy enough and air-tight

well it doesn't need to be made using MDF or wood even
you can make it out of plexiglass if you want
it will vibrate like crazy, but it would still be a sealed enclosure
and i think the weatherstripping you refer to helps minimize vibrations transfered to the sill cavity.
the most vibration you normally get is from the back wave of the woofer
and that is hitting the plastic enclosure directly.
when i listen to the subs from the ouside
there isn't a lot of vibration heard outside the car
so while i agree its not 100% sealed, i think it does a very good job
my SWS-8s sound really good
and if i wasn't too anal about having some sound in the 20-40hz range
i would skip having a trunk mounted sub

[kaigoss69]

Originally Posted by Technic

There is a thread of this install in this forum...

I looked everywhere but I cannot find that thread. Would you have the link by chance? Thanks.

[VP Electricity]

Originally Posted by kaigoss69

I've actually read over on DIY that that location, from an acoustical standpoint, may not be too bad at all, as long as you don't try to play voices.

LOL

Originally Posted by kaigoss69

Well, my knowledge is not that deep on this subject, but I thought the main purpose of the baffle was to separate the front waves from the back waves to avoid cancellation.

Correct. This is either by means of an enclosure, or by a panel which is sufficiently larger in area than the driver.

Originally Posted by kaigoss69

If that is true, then take a look at the OEM enclosure and tell me that is not essentially the same thing - the back waves are contained within the enclosure and are allowed to resonate through the port, totally separated from the front waves. If you agree with that, then what is wrong with the concept I suggested earlier which in my mind is doing exactly what the OEM enclosure does, but with a larger volume and the capacity for a deeper driver.

What you are suggesting theoretically is workable, but your suggested approach is what I am skeptical about.

Just put Morel ADMW9 in a 1-series, thinking about doing it in mine. Will post pics...

[quality_sound]

I think he's right. Midbass isn't localizable under about 250Hz anyway. I know the horrible placement in my GTI didn't hurt anything.

I'm actually tempted to run a 6.5" in there, even if temporarily, since there are many more available and I might be able to offset the driver enough to be able to space it up for deeper units.

Did the Morel fit in the OEM location or did you have to make something custom? Looking forward to the pics.

[808MGuy]

Originally Posted by VP Electricity

LOL
Just put Morel ADMW9 in a 1-series, thinking about doing it in mine. Will post pics...

When I was asking around about the ADMW last year I was told that it was no longer available. Looking forward to seeing some pics though.

[VP Electricity]

Originally Posted by quality_sound

I think he's right. Midbass isn't localizable under about 250Hz anyway. I know the horrible placement in my GTI didn't hurt anything.

We've had this conversation before... We disagree on it... at least, I believe that some people can localize speakers in cars with 90 Hz high-pass filters, which is a more specific application of the concept which perhaps we can agree on.

Originally Posted by quality_sound

Did the Morel fit in the OEM location or did you have to make something custom? Looking forward to the pics.

See here, 2nd post:

http://www.e90post.com/forums/showthread.php?t=340809

[quality_sound]

Originally Posted by VP Electricity

We've had this conversation before... We disagree on it... at least, I believe that some people can localize speakers in cars with 90 Hz high-pass filters, which is a more specific application of the concept which perhaps we can agree on.



See here, 2nd post:

http://www.e90post.com/forums/showthread.php?t=340809

Honestly, it could be car dependant. No one was able to localize the midbasses in my GTI but even at the back of the door it's a world better location than under my ass. I'm seriously thinking about just tossing the idea of an 8 out and having Bing whip me up some nice door pods for some 7s.

Are you talking about localizing a mid with a 90Hz high pass? Or did you mean low pass? If you meant a mid, I totally agree. I just can't wait to pick the car up (Tuesday at the latest) and start playing with it.

[VP Electricity]

I guess I mean that I've personally, and had customers, localize woofers low-passed in the back with xo points below 250, and also bandpassed midbasses in the back with LP points below 250 and HP at 50 or so. So I'm kinda gun-shy.

But as far as putting Morel ADMW8 in, they should not be scary...looking to do it in mine soon.

[VP Electricity]

Originally Posted by kaigoss69

I know about that installation but I always wondered about the enclosure size in relation to the driver's Qts value of .74 ... seems to be better suited for free-air.

If you're running it as a midbass, I don't think it's a big issue. It's probably intended for big doors or something, but as a woofer - so as a midbass bandpassed, I'm not concerned about that too much.

I may get access to this car again and do some FFT on the 8 only, if I can. Be a lot of work due to the passives.

[kaigoss69]

Originally Posted by VP Electricity

Just put Morel ADMW9 in a 1-series, thinking about doing it in mine. Will post pics...

Can't wait for the pics. What kind of enclosure???

[VP Electricity]

Originally Posted by kaigoss69

Can't wait for the pics. What kind of enclosure???

Sumpin' like:

[quality_sound]

Originally Posted by VP Electricity

I guess I mean that I've personally, and had customers, localize woofers low-passed in the back with xo points below 250, and also bandpassed midbasses in the back with LP points below 250 and HP at 50 or so. So I'm kinda gun-shy.

But as far as putting Morel ADMW8 in, they should not be scary...looking to do it in mine soon.

Ahh, yeah I can see that especially having to deal with customers. sometimes I miss the retail portion of car audio and sometimes I really dont.

[kaigoss69]

Originally Posted by VP Electricity

Sumpin' like:

I see. Questions:

1. Why did you have to take off the top layer/cover from the OEM enclosure?
2. What material is the spacer ring?
3. How far away from the seat rail is the Morel grille?
4. Do you have to raise the seat?
5. Most importantly, how the HELL does it sound?????????

Great work, man!

[ianbiz]

good thread, dont know how i missed it.