# No Bass with an Infinity 6x9 693.7i in an Enclosure



## jkissit (Sep 20, 2007)

I was stupid and just bought a truck box to put my Infinity 693.7i speakers in. Well the box appears to be way too small and I have absolutely no bass below 100hz and a peak at 200hz. I called Infinity and they could/would not give me a recommended enclosure or T/S parameters.

I would like to build a new box. Does anyone know what size box to use? I was debating on using a ported box since I have no sub. Does anyone know the T/S parameters? Or could anyone measure the T/S parameters? I live in the LA area.

Thanks
Jeff


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## tyroneshoes (Mar 21, 2006)

It sounds kinda silly to have a full range 6x9 in a box. You might want to look into these

http://www.partsexpress.com/pe/showdetl.cfm?&Partnumber=264-864

are you using an amplifier?


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## jkissit (Sep 20, 2007)

Yeah I am using a rockford fosgate 300x. It should be outputing about 75 watts rms. 
The speaker in installed in a toyota mr2. They are in a box behind the seat facing up. I previously had a pair of Boston Rally 6x9's in a box and had great results. All i want is solid midbass and rear-fill. Since I already have the 6x9 inch speakers I would like to try to make that work. 
In a car the 6x9's should be able to output 40hz pretty strong in a box. The infinity's have a long throw. Maybe I could just cut a hole or port the current box. 
Any help would be appreciated. Including a suggestion of a better forum to go to if this is the wrong one. I am just asking here since you guys seem to be nice and know what you are talking about mostly.


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## HondAudio (Oct 19, 2006)

Make the boxes have aperiodic vents to the outside of the car underneath


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## mvw2 (Oct 2, 2005)

You won't get much bass from them anyways. Infinity as a brand is pretty bassless, even their 6x9 woofers are quite light on the low end. You would pretty much have to build a ported enclosure for it, but you'd need T/S specs to do so. I'm suprised Infinity wouldn't give them.


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## jkissit (Sep 20, 2007)

Do you think I might be ok with just cutting a 1" hole in the box? I know it is kinda ghetto, but without parameters I can't build a ported box and a sealed box would be huge and still wouldn't respond all that well.
Right now the box has to be killing the low end bass down to less that 60db. So if i unseal the box at least I wont loose as much bass. Or I could always just build a sealed box as large as my space allows.

Those parts express 6x9" subwoofers looked really bad when I modeled them. Pretty much midbass only. 

Thanks
Jeff


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## Whiterabbit (May 26, 2006)

youll never get bass out of that 6x9. the cone flexes way too much. if you wanna see something really neat, play a sweep on the driver in a dark room with a strobe light on. Might wonder how the cone isnt tearing!


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## DejaWiz (Sep 20, 2007)

I've never really known any 6x9s to perform well in those small prefab boxes. Of course, I haven't used many 6x9s. 

I helped a friend install a system into an '89 Accord a long while ago. He bought some Kenwood 4-way 6x9s that were on clearance at a local store and a pair of those Wal-Mart boxes for them so he could mount them on the rear deck facing towards him. The bass sounded muddy and lacked any sort of low end... I'd say they were pretty worthless below 120-150Hz. 

After a while, he finally ditched the boxes and surface mounted them on the rear deck. Made a HUGE difference. I like Kenwood speakers for their upper-mids and highs, but dang it sounded like he had a tiny sub bp'd at 40 to 100Hz in the trunk. And all this was off HU power.


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## OldOneEye (Jun 16, 2005)

Wow.. A little surprised at the responses. 

Those speakers were designed to play free air loaded into your rear deck (or rarely into a door). They are designed for a big, somewhat leaky enclosure. Put them into a small, tightly sealed one and the low end goes away.

I've heard 6X9 pound out some good bass when you have good power to them. But always in a rear deck (usually a sedan, hatchbacks with hatch covers don't seal the front to back wave as well).

Don't think porting it will help (still in a small box). Maybe a hole will help (some guys who use kick panels put a hole into them firing into the carpet to vent them a little bit, seems to work but that is a midbass application).

Juan


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## 60ndown (Feb 8, 2007)

check your high pass filter ?

make sure the amp is set to 'full range'

6x9s can produce plenty of bass


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## jkissit (Sep 20, 2007)

The speaker is moving some with the low frequencies. You can tell it is getting the signal. The highpass filter is turned off. The problem is that this speaker was designed to work in a infinite baffle(huge sealed box). 
I have attached the typical response of a speaker in a box that is way too small. This is exactly the way that my 6x9 inch speaker sounds. There is almost no bass below 100hz and there is a huge resonance at about 200hz.

I guess I could try stuffing the current boxes and cutting the hole. I am not trying to emulate sub. I just want some bass and I want to get rid of the resonance. Or I might build a new sealed box. I am not an experienced box builder though and it would take me a while to complete. Plus I dont have a ton of room. I don't know if I could build the boxes bigger than 1ft3. Without the T/S parameters I dont know if that will be big enough. Plus I would much rather do a ported box if I am going to go through the trouble.

I contacted Infinity again and the still say that they dont have the T/S parameters. And they dont have any box recommendations since they are designed to work in a large box. But wouldn't you need T/S parameters in order to design the speaker to work in IB?

Thanks for all of your comments and recommedations. The more the better. Especially if any of you live near Santa Barbara and have wood working material.

Thanks
Jeff


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## 60ndown (Feb 8, 2007)

find some plastic pipe at your hardware store about 1 or 2" , cut a hole and play with different lenths of the pipe for best results.

you can always plug the hole if its worse :blush:


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## DejaWiz (Sep 20, 2007)

Or just drill as many good sized holes in the boxes as you can to take away the air suspension qualities and make it a free-air setup.


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## MidnightCE (Mar 5, 2007)

cancellation?


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## jkissit (Sep 20, 2007)

I put the balance completely to one side and did not notice the bass go up at all. Here is my conversation with Infinity. Is he correct? From what he is saying there is no possible way to make this speaker sound good in a box. Or is he just too lazy to find the person who actually knows?

It is reverse order sorry.


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Subject: RE: Message from Infinity
Date: Thu, 4 Oct 2007 10:38:51 -0400
From: [email protected]
To: [email protected]

An "infinite baffle" means just that, the enclosure in theory never ends. And it is not sealed. So, the parameters are unavailable and would be invalid for this application. 



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From: Jeffrey K [mailto:[email protected]] 
Sent: Thursday, October 04, 2007 2:49 PM
To: Lacinski, Ed
Subject: RE: Message from Infinity



Wouldn't you tweek the Thiele/Small parameters in order to design a speaker to work in an Infinite Baffle? All infinite baffle means is very large sealed box. To be operating as an infinite baffle you just have to be 3-10times the Vas for the speaker.

Is there anyone there has the Thiele/Small parameters for this speaker. Is there anyone else I could contact there? Or could someone measure the T/S parameters for a driver you have there?

Any help would be much appreciated.

Jeff



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Subject: RE: Message from Infinity
Date: Thu, 4 Oct 2007 10:38:51 -0400
From: [email protected]
To: [email protected]


The 693.7i is designed to be mounted in a door panel or deck. This is called a "free air" installation or infinite baffle. That is why no particular enclosure size can be recommended and Thiele/Small parameters are not available. 



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From: Jeffrey K [mailto:[email protected]] 
Sent: Thursday, October 04, 2007 2:26 AM
To: Lacinski, Ed
Subject: RE: Message from Infinity


I called tech support the other day about a recommended box size or T/L parameters for the 693.7i. They did not know the parameters or box size. Can you find the parameters so I can build a box to fit behind my seat? It would be much appreciated.

Thanks
Jeff


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