Need to smooth upper bass of sub response... - diyAudio
Go Back   Home > Forums > Loudspeakers > Subwoofers

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 24th August 2003, 11:00 PM   #1
diyAudio Member
 
Join Date: Jul 2003
Location: maryland, USA
Send a message via AIM to eRiCdWoNg
Default Need to smooth upper bass of sub response...

....I'm using an Adire Tumult with my Magnepan MGIIIA speakers. They complement each other much better then my last setup of my 100 db PA speakers and the Tumult. The Maggies are in the range of 85 dB efficiecy and I believe the Tumult is right around there. Im now using an Adcom GFA2535 4 channel amp with 2 of the channels bridged running the 2 voice coils of the Tumult in series. I'm using this configuration because this ensures both voice coils are getting = power and material.

The sound- well takes some getting used to since I'm used to the extreme power of the PA system that was there before hand. This system is much more detailed and bad recordings are much more obvious. Also the amplifier is dead quiet, unlike the PA amps which had fans that turn on and buzzing huge iron core transformers. I kinda miss the punch and slam of the PA system but this system is geared entirely different.

Now, heres what I'm getting at- from listening and from my RTA the upper bass is kinda weak. My X over is 90 Hz with a Linkwitz-Riley alignment. 60 Hz comes up kinda weak (it did in the car too when I used this woofer in the car), as indicated by RTA and my ears. I want to boost this up. Should I make the box smaller?

The box is sealed, its a sonotube enclosure. 2.5 cubic foot after driver displacement. And I did do the phase reversal to make sure it wasnt phase cancellation.
  Reply With Quote
Old 26th August 2003, 02:51 PM   #2
AndersP is offline AndersP  Sweden
diyAudio Member
 
Join Date: Aug 2002
Location: Middle Sweden
Closed box Tumult would be pretty free of dips in the 60 Hz region.

Room modes?

Move the sub around in the room to find hot spot.

and/or

Use an equaliser. Industrystandard being the Behringer Feedback Destroyer.
  Reply With Quote
Old 26th August 2003, 04:41 PM   #3
diyAudio Member
 
Join Date: Mar 2003
Location: Austin
Send a message via AIM to ScottRHinson
My guess is that you're discovering the difficulty of successfully mating two different technologies of speaker, ribbon vs. dynamic, line source vs. point source...etc.

Check out the difficulty in measuring the true response of the Magnepan in a room, and you'll get an idea of what you are in for. Don't get stuck on setting the high-pass and lowpass xovers at the same frequency or slope, and be prepared to experiment A LOT.

http://www.stereophile.com/showarchives.cgi?303:6

Scott
  Reply With Quote
Old 27th August 2003, 02:29 AM   #4
diyAudio Member
 
Join Date: Jul 2003
Location: maryland, USA
Send a message via AIM to eRiCdWoNg
Yeah I'm actually replacing my old sub that I had going for the past 5 years. It was a 12" Cerwin-Vega car audio sub, but I tuned it to "home audio" specifications in a 5 cubic foot vented sonotube enclosure. Surprisingly, it integrated very well and I was very happy with the sound to my ears and on RTA. I might redo that enclosure again as I pasted 2 sections of tube together.

Right now, the 2 different types of speaker is painfully obvious. Theres alot of 50 hz and below energy, so everything rumbles and you can feel that subsonic energy. Its fine for movies, but listening to other music where you expect the "punchiness" in the upper bass, with the Tumult's lack of 60 hz and the maggie's dipolar nature, the sound just doesnt integrate. Its even worse on music that contains a variety of bass material.
  Reply With Quote
Old 27th August 2003, 04:01 AM   #5
diyAudio Member
 
Join Date: Sep 2002
Location: Australia
Why not try the Tumult as a dipole?

Just build a simple baffle like the one here:

http://www.linkwitzlab.com/proto.htm#PW1

Of course you'd need two if you want to go stereo, plus dipole EQ, but just this simple baffle will give you an idea what to expect.

IMHO, you will get better results by having the same radiation patterns throughout the range, and dipole bass is excellent in any case.

Steve
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
12 " for lower midrange - upper bass Audiodidakt Multi-Way 33 23rd June 2009 05:39 PM
Getting good Efficiency and smooth response, to 3-4-5-way, or not pjpoes Multi-Way 86 31st July 2008 11:56 PM
Dipole Woofer for upper bass Recommendation Hara Multi-Way 5 11th June 2007 08:39 PM
Rear Loaded Smooth Bass? Mark in NJ Multi-Way 7 29th September 2005 04:28 PM


New To Site? Need Help?

All times are GMT. The time now is 09:37 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2014 DragonByte Technologies Ltd.
Copyright 1999-2014 diyAudio

Content Relevant URLs by vBSEO 3.3.2