[smartcar111]

Hey guys!

It took me four years to finally get around to doing this install! I've wanted more bass in the smart system even though it had the underseat sub, that's sub-par on so many levels!

Butch and I decided to go ahead and install the Infinity Basslink in the trunk of the smart. The price was very reasonable as compared to the under dash models which cost way more than $250! The Basslink is 200 watt RMS and was on Crutchfield for $199 with a $30 wiring harness included with free shipping. I also bought the $30 3 year extended warranty because people have complained that these subs burn out quickly and recommend the extended warranty.

Here are a couple of pictures now! We need to add one more quick disconnect to the system and then I'll put up more pictures and videos! I've been driving around with it for a day now tuning it and maxing out the potential and I'm extremely impressed!

 

[kheran]

Looking good!!! What did you do with the underseat woofer? I hope the purists out there don't ask "why not two subs" or "you better more that thing to the other side--You're throwing off the balance of the car".

 

[Bosgarage57]

I like it too, but cant give up the storage space.

 

[deepblueQ]

... I hope the purists out there don't ask "why not two subs" ...

Oh the horror! Two subs would just interfere with each other and give all kinds of artefacts!

Looks good. Sealed enclosure, it looks like?

 

[smartcar111]

What did you do with the underseat woofer?

Still intact!

 

[smartcar111]

Sealed enclosure, it looks like?

You are correct! It's actually one active subwoofer on top and a passive subwoofer/radiator on the bottom. This will help incorporate the benefits of a sealed enclosure with the benefits of a ported box!

 

[deepblueQ]

Still intact!

Arg! I wasn't actually kidding about 2 subs hurting sound quality... you might see how you like it with the stock one unplugged...

You are correct! It's actually one active subwoofer on top and a passive subwoofer/radiator on the bottom. This will help incorporate the benefits of a sealed enclosure with the benefits of a ported box!

Your explanation of how it works isn't quite enough, and the Infinity site seems a bit sparse on details...

I did see a reference on their site to a high-pass filter being used to prevent over-excursion below the resonant frequency of the porting (indicating that there is some porting of some sort).

 

[smartcar111]

Arg! I wasn't actually kidding about 2 subs hurting sound quality... you might see how you like it with the stock one unplugged...

Maybe, but from my listening experience, it doesn't distort any audio. If anything, it vibrates the seat.

Your explanation of how it works isn't quite enough, and the Infinity site seems a bit sparse on details...

This quote was from the site. Does this help in the explanation? There is no port. The box is sealed but it's not a traditional sealed box. On the underside of the active subwoofer, there is a passive subwoofer just like the active one but with no power. This is designed to help radiate more of the subwoofer without the need for a port which requires a larger box to achieve the same sound level and intensity. Because it has a passive subwoofer, it has the benefits of a ported box and a sealed box at the same time!

BassLink consists of a 10-inch subwoofer, 10-inch passive radiator and a 200-watt Class D amplifier housed in a rigid polymer enclosure, all carefully engineered to work together as a unique, integrated system. The extremely versatile BassLink accepts both speaker- and line-level inputs, and it provides an internal low-pass filter, proprietary signal processing and abundant amplification.

 

[smartcar111]

Also,

A speaker enclosure using a passive radiator usually contains an "active driver" (or main driver), and a passive radiator(also known as a "drone cone"). The active driver is a regular driver, and the passive is typically the same or similar, but without a voice coil and magnet assembly. It is only a suspended cone, not attached to a voice coil or electrical circuit. The passive radiator usually has some means to adjust its mass, thereby allowing the speaker designer to change the box tuning. Internal air pressure produced by movements of the active driver cone moves the passive radiator cone as well.

Passive radiators are used instead of a reflex port for much the same reasons—to tune the small volume and driver for better low frequency performance. Especially in situations in which a port would be inconveniently sized (usually too long for practical box configurations). They are also used to eliminate port turbulence and reduce motion compression caused by high velocity airflow in small ports (especially small diameter ones). Passive radiators are tuned by mass variations (Mmp), changing the way their compliance interacts with motion of the air in the box. The weight of the cone of the passive radiator should be approximately equivalent to the mass of the air that would have filled the port which might have been used for that design. Passive radiators do not behave exactly as do (more or less) equivalent bass-reflex designs in that they cause a notch in system frequency response at the PR's free air resonant frequency; this causes a steeper roll-off below the system's tuned frequency Fb, and poorer transient response. Due to the lack of vent turbulence and vent pipe resonances, many prefer the sound of PRs to reflex ports. PR speakers, however, are more complex to design and likely to be more expensive as compared to standard reflex enclosures.

The frequency response of a passive radiator will be similar to that of a ported cabinet, with two exceptions. The system low frequency roll-off in a passive radiator design will be slightly steeper, and will have a notch (dip) in frequency response due to the Vas (compliance, or stiffness of the speaker cone) of the passive radiator. The goal in designing a passive radiator is to adjust the tuning so that this notch is below audible levels.

Source

 

[Stretchmobile]

Looks great SM111. Probably sounds awesome. I am happy with my sub. Small cab, 4 speakers and a sub really makes music sound great. Here is mine, post 10.

http://www.smartcarofamerica.com/forums/f76/has-anyone-put-infinity-basslink-under-thier-seat-43595/

 

[kheran]

Arg! I wasn't actually kidding about 2 subs hurting sound quality... you might see how you like it with the stock one unplugged...





Your explanation of how it works isn't quite enough, and the Infinity site seems a bit sparse on details...

I did see a reference on their site to a high-pass filter being used to prevent over-excursion below the resonant frequency of the porting (indicating that there is some porting of some sort).

It would be defeating the purpose of the passive radiator if the cabinet was ported. High pass is used to "flatten" out the low end resonance to control the passive radiator.

 

[deepblueQ]

Maybe, but from my listening experience, it doesn't distort any audio. If anything, it vibrates the seat.

The two subs will create standing waves in different spots. At some frequencies they'll be in phase (loud) and at some they'll be out of phase (quiet). Distortion isn't the issue, a lumpy frequency response band is the issue.

Because it has a passive subwoofer, it has the benefits of a ported box and a sealed box at the same time!

Passive radiators do not behave exactly as do (more or less) equivalent bass-reflex designs in that they cause a notch in system frequency response at the PR's free air resonant frequency; this causes a steeper roll-off below the system's tuned frequency Fb, and poorer transient response. Due to the lack of vent turbulence and vent pipe resonances, many prefer the sound of PRs to reflex ports.

Looks like they're probably a bit better than a ported enclosure, but they've still got some of the ported enclosure's troublesome aspects (namely the lumpy frequency response band and slow transients).

 

[smartcar111]

The two subs will create standing waves in different spots. At some frequencies they'll be in phase (loud) and at some they'll be out of phase (quiet). Distortion isn't the issue, a lumpy frequency response band is the issue.





Looks like they're probably a bit better than a ported enclosure, but they've still got some of the ported enclosure's troublesome aspects (namely the lumpy frequency response band and slow transients).

The underseat sub isn't loud enough to make any type of difference in the low end of the spectrum. Honestly, my side speakers drown out the underseat sub before it can be heard to make any difference on the low end of the spectrum. The reason why it's still intact is because it does vibrate the seat a little bit and I guess the placebo effect of it still being there does something. Also, if it does add, when my Basslink is out of the car, it will still be there thumping away.

Also, yes it does still suffer from some aspects of a ported enclosure, but since my head unit has an equalizer for the subwoofer, I can gain where the lumps begin to occur in the frequency band. Instead of a linear power spectrum across the entire band the subwoofer if capable of, I can add where the dips in the response are to make up for that which is what I have been working on doing for the past couple of days now.

The Basslink far out powers the underseat sub that even if they were in phase or not in phase, the difference wouldn't be heard that greatly and because of the ability to adjust the equalizer on the Basslink sub, I can add where it needs to be added to when it begins to create a lumpy response.

 

[smartcar111]

Here's another picture of it in the back next to my two ball bowling bag! Thought I would have to remove the sub because of my bag, but I guess not!

 

[Miss Mercedes]

I'm glad I'm not the only one with random debris on my carpet...I clean my wheels bi-daily but have only twice brought out the vacuum...

I've been trying to leave the audio system alone but you and forest keep creating interesting ways to reel my interest in!

Looks great! ...wait...where's that NOS bottle?

 

[smartcar111]

I'm glad I'm not the only one with random debris on my carpet...I clean my wheels bi-daily but have only twice brought out the vacuum...

I've been trying to leave the audio system alone but you and forest keep creating interesting ways to reel my interest in!

Looks great! ...wait...where's that NOS bottle?

My carpet will get cleaned once it's out of the collision center. I cannot wait for that!

Also, the audio system is one of the best upgrade options you can do after you are done with performance upgrades. You have no idea what you are missing!

Also, the NOS bottle is mounted on a piece of black plexiglass and on the bottom of that plexiglass, there are three long strips of industrial strength velcro that hold it to the carpet. On the feet of the subwoofer, there are four rectangles of plexiglass with industrial strength velcro on the bottom of that. I can interchange the subwoofer for the NOS bottle when I'm going to a car show and want to use my plexiglass engine cover since the subwoofer won't fit in the back with the plexiglass engine cover. I could have both in at one time if I didn't use my plexiglass engine cover or didn't need to. That's why I made both the NOS tank and the subwoofer totally removable.

 

[deepblueQ]

The underseat sub isn't loud enough to make any type of difference in the low end of the spectrum. Honestly, my side speakers drown out the underseat sub before it can be heard to make any difference on the low end of the spectrum. The reason why it's still intact is because it does vibrate the seat a little bit and I guess the placebo effect of it still being there does something. Also, if it does add, when my Basslink is out of the car, it will still be there thumping away.

Also, yes it does still suffer from some aspects of a ported enclosure, but since my head unit has an equalizer for the subwoofer, I can gain where the lumps begin to occur in the frequency band. Instead of a linear power spectrum across the entire band the subwoofer if capable of, I can add where the dips in the response are to make up for that which is what I have been working on doing for the past couple of days now.

The Basslink far out powers the underseat sub that even if they were in phase or not in phase, the difference wouldn't be heard that greatly and because of the ability to adjust the equalizer on the Basslink sub, I can add where it needs to be added to when it begins to create a lumpy response.

So no issue with the two subs, I guess.

I'd still pick a sealed enclosure myself, but that's kinda personal preference - excessive volume just gives me a headache, I go for quality over quantity.

 

[acidhax]

My subwoofer sounds pretty good, but when a window is open... it gets noticeably louder.

Does this happen to you all?

 

[deepblueQ]

My subwoofer sounds pretty good, but when a window is open... it gets noticeably louder.

Does this happen to you all?

I don't have a sub, but I've got a bit better bass with the windows up. I'm guessing it's effectively port-tuning the interior for one particular frequency, amplifying at that point. I haven't done the math, really got no clue.

 

[smartcar111]

I'd still pick a sealed enclosure myself, but that's kinda personal preference - excessive volume just gives me a headache, I go for quality over quantity.

I'm a huge fan of the sealed enclosures tight response bass and accurate reproduction of how the low frequencies should be represented, but I'm also a fan of the loud shattering bass of a ported sub. The design of this enclosure is the best of both worlds! I'm surprised many other manufacturers don't do this, but I heard it was an expensive R&D. Steve Meade designs just did this for his towers in his shop.