Click Banner for Details on this Saabnet.com Classified

I'll explain how I recently achieved some mid/upper bass up front in my '91 9000T.

If you remove the left side kick panel in the passenger footwell, you will find that there is a fairly large open space on the floor just behind the firewall. I created a mini-woofer using two cheap 4" drivers mounted in an isobaric "push-pull" configuration, loaded in a small sealed 5.5" cube enclosure. The drivers face backwards, towards the trunk.

I then rolled off the woofer with a 2nd order (12db/octave) crossover above 300hz and used two channels from a four channel amp to power each driver (one in phase, one out of phase). I balanced the amp to deliver more power to the woofer because it needs to penetrate through the kick panels. Having the woofer behind the panels further reduces the audibility of the midrange and any distortion that may occur.

Mounting the woofer this way feeds mid /upper bass (and some lower midrange) into both footwells from a single enclosure - without having to cut any holes in the doors or anywhere else, and it takes up absolutely no useable space.

The isobaric algnment (two woofers mounted face to face, and out of phase) doubles the effective volume of the enclosure - so my 5.5" isobaric cube has a output similar to a single woofer in a 7" cube.

The results are solid upper bass in front, and some useable midbass (down to about 60hz). It peaks around 120hz. Listening to the front speakers alone, it is impossible to tell that there is a separate woofer.

The front speakers blend with the rears far better now, and the bass does not seem so localized in the rear. The clairty of the main front speakers is also improved, because the burden of producing bass has been removed.

I build all of my own enclosures, so the 5.5" cube was a custom design; I don't think you could actually buy such an enclosure anywhere.

-Kyle
'91 9000T

posted by 24.60.14...

• Need a new stero setup, what to get? PART 2, Brian, Mon, 14 Oct 2002 10:52:49
  • D/A converter resonably explained -, Kyle, Mon, 14 Oct 2002 22:33:33
    • Re: D/A converter resonably explained -, Jan Geert, Tue, 15 Oct 2002 04:06:57
      • Jan is correct, Bill Cannastra, Tue, 15 Oct 2002 16:13:55
        • Rrroarrr! High-end technical jargon confuse Kyle! >>>, Kyle, Wed, 16 Oct 2002 04:31:21
          • I think Kyle's becoming the Hulk, Bill Cannastra, Wed, 16 Oct 2002 17:10:46
  • RMS power resonably explained -, Kyle, Mon, 14 Oct 2002 21:08:39
  • How I achieved bass up front (long) >>>, Kyle, Mon, 14 Oct 2002 19:31:07 <-- Viewing This Message
  • Re: Need a new stero setup, what to get? PART 2, TJ, Mon, 14 Oct 2002 17:23:22
    • TJ, sounds like..., Aerogant, Tue, 15 Oct 2002 11:30:23
      • Re: TJ, sounds like..., TJ, Tue, 15 Oct 2002 13:54:23
        • Re: TJ, sounds like..., Aerogant, Tue, 15 Oct 2002 14:40:46
          • Re: TJ, sounds like..., TJ, Tue, 15 Oct 2002 15:09:41
            • Re: TJ, sounds like..., Aerogant, Tue, 15 Oct 2002 21:03:04
  • Re: Need a new stero setup.., Andrew , Mon, 14 Oct 2002 13:42:30
    • I had those capasitors in my 87 when I bought it->, roman, Mon, 14 Oct 2002 17:22:10
  • How ambitious are you?, Aaron Gilbert, Mon, 14 Oct 2002 12:06:07

No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.

• Prev by Date: Like it or not..., Yaofeng, Mon, 14 Oct 2002 19:14:05
• Next by Date: Re: wont start, Sjer, Mon, 14 Oct 2002 19:52:39
• Main 9000 Bulletin Board

StateOfNine.com

SaabClub.com

Jak Stoll Performance

M Car Covers

Ad Available

The content on this site may not be republished without permission. Copyright © 1988-2024 - The Saab Network - saabnet.com.
For usage guidelines, see the Mission & Privacy Notice.
[Contact | Site Map | Saabnet.com on Facebook | Saabnet.com on Twitter | Shop Amazon via TSN | Site Donations]

Random Saabnet.com Member Gallery Photos (Click Image)