Bass Boost - 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 17th July 2005, 01:11 AM   #1
diyAudio Member
 
Join Date: Apr 2005
Location: New Jersey
Default Bass Boost

I want to model a sub with an amp that has bass boost of +5db at 35hz. Should I model the vented box to be -5db at 35hz for a flat response? The box will also be smaller and more room friendly.
  Reply With Quote
Old 17th July 2005, 01:39 AM   #2
SY is offline SY  United States
diyAudio Moderator
 
SY's Avatar
 
Join Date: Oct 2002
Location: Chicagoland
Blog Entries: 1
Isn't this a bit backward? Normally, you start with the box, then determine what eq you need to flatten the response.

In any case, if there's a specific reason for designing to that boost (like you have a plate amp with that built in and you don't want to take it out), yes, drop the box tuning frequency to get the driver to roll off enough that it's down 5 dB at 35Hz.
__________________
And while they may not be as strong as apes, don't lock eyes with 'em, don't do it. Puts 'em on edge. They might go into berzerker mode; come at you like a whirling dervish, all fists and elbows.
  Reply With Quote
Old 18th July 2005, 08:04 AM   #3
Collo is offline Collo  Australia
diyAudio Member
 
Collo's Avatar
 
Join Date: Nov 2004
Location: Newcastle, Australia
Send a message via MSN to Collo
Default Amp Boost

I have built a few subs using amps that have Bass boost. I use WinISD pro which has a section that lets you add filters including a Parametric equaliser. For 6dB boost, I reduce power to 25% of the normal rating, so the output at the boosted frequency will be 100%. For your situation of +5dB, it will be slightly different.

Here's a link to my setup in WinISD
http://www.users.bigpond.com/bcolliso/WinISD-boost.htm

I find that with careful selection of tuning frequency, using a boosted amp in a ported design can save you needing an infrasonic filter to control excursion.

regards
Collo
__________________
Ports rule!
  Reply With Quote
Old 22nd July 2005, 05:37 AM   #4
rcw is offline rcw  Australia
diyAudio Member
 
Join Date: Jul 2005
Location: sydney nsw
Default re filter

This type of filter is used on the QB5 class I type of reflex alignment. This is much used in professional designs as it comes close to an optimum size/extension/output solution.
I recently published an article on Rod Elliots website that outlines an easy way to design such enclosures.
Basically if your driver has a standard B4 alignment that requires a tuning frequency that is 35Hz./0.7. then tuning it to 35Hz. gives a flat output when used with this type of filter, as well as greatly improving the power handling and providing a l.f. filter.
By compliance scaling you can fit a wider variety of drivers to these alignments.
  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
bass boost odysseybmx414 Chip Amps 3 26th August 2005 10:05 AM
Bass Boost Q UNDERSTANDIN Subwoofers 5 26th July 2005 09:49 PM
bass boost lawbadman Solid State 4 29th August 2003 03:20 PM


New To Site? Need Help?

All times are GMT. The time now is 09:01 PM.


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