Go Back   Home > Forums > >
Home Forums Rules Articles diyAudio Store Blogs Gallery Wiki Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Double Bass Reflex.
Double Bass Reflex.
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
Thread Tools Search this Thread
Old 20th July 2006, 03:52 PM   #21
MJK is offline MJK  United States
Account disabled at member's request
Join Date: Feb 2002
Location: Clifton Park, NY

I hope you don't take offense. You are asking me to do work for you. As was discussed several times above, I think you are clearly in the DIY phase of speaker building.
  Reply With Quote
Old 20th July 2006, 07:04 PM   #22
LightwaveDude is offline LightwaveDude  United States
diyAudio Member
Join Date: Nov 2005
Nope. No offense taken, but I've always been told it doesn't hurt to ask!

  Reply With Quote
Old 21st July 2006, 11:39 AM   #23
Zero One is offline Zero One  Australia
diyAudio Member
Join Date: Apr 2006
Location: Goulburn NSW
Hi there lightwave and interested DBers.

I have built DBs based on the fostex design (127) and used different drivers in them as an experiment, overall the DBs work really well, in fact far better than I thought possible.

I have no program for simming and I don't even have the parameters for the drivers I used, they were cheap, but I managed to get there eventually, there are of course many variables, bottom and top chamber size, internal port length/diameter and the bottom port.

Basically I just experimented with everything in sacrificial boxes, in other words i didn't care how trashed the boxes got as they were just prototypes.

So heres an idea make a basic pair of boxes that are larger than you think you'll need and make sure the divider inside the box is not fixed so you can move it up or down, if you make the fit tight enough it should hold for experimenting.

The bottom chamber can be adjusted by using blocks of wood or other solid regular shaped objects or even sand in known quantities. Ports can be adjusted by using cardbaord tubes that can be cut at will.

Try a top port dia of 65mm or so and 60mm lenght, though you will likely not finish with this and adjust the top chamber until the mids/highs sound right, then adjust the volume of the bottom chamber until you start to get some bass happening with a shortish bottom port tube (say 60mm by 60mm), then you can start tuning port lenghts, but don't tune the top one too low say around 100hz or so.

To make it work you will need a CD with some tone sweeps or test tones on it at everything from 20hz through to say 16khz.

I know none of this sounds really scientific, but it will work if you persevere and you will probably end learning a heap about how port lenght and cab size effects the sound.

OH and there are other things that I imagine most simms don't take into account that you can play with too, like distance from the walls/corners, height from the floor, the resonance of the cabs, the type of stuffing you use in the cab, mods to drivers and much more, all these things can have big time effects on the sound IMHO and are likely hard to predict via programs alone.

Go ahead have a play with some cheap drivers and cabs, you have little to lose and a heap to gain.

Programs would I'm sure help a lot in terms of cutting down the time involved and I really admire the guys who have created them, but in the end I'd say they would land you in the ball park and theres no guarentee you will like the way they sound without fine tuning anyway, after all what you and I think sounds good is pretty personal.

Hope it helps.
  Reply With Quote
Old 31st July 2006, 10:56 AM   #24
DAMIC is offline DAMIC  Seychelles
diyAudio Member
Join Date: Jan 2006
Location: Beograd

I just now discovered this thread, I am glad that some other members also achived unusaly good bass response with DBR. It seems that I accidently made DBR, increasing the volume of my stock hybrid speaker, last week I posted the topic under the speaker page: Apogee C/M mod what I ended with


I am still curious, how astonishing bass performance achived with 6,5 inch driver.

Best regards
  Reply With Quote
Old 31st July 2006, 11:57 AM   #25
Zero One is offline Zero One  Australia
diyAudio Member
Join Date: Apr 2006
Location: Goulburn NSW
Yeah, you sure can get great results, I have had many friends lsten to mine and they have all commented how good the bass was considering the driver size. The thing I like however is that the bass is nicely tight and very tuneable.
  Reply With Quote


Double Bass Reflex.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

Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
Fostex FE107E Double Bass Reflex Enclosure RemoGaggi Multi-Way 1 9th January 2009 01:25 PM
FE103 isobaric double bass reflex box Andrewbee Full Range 5 29th December 2006 01:34 AM
Optimized double bass reflex youyoung21147 Full Range 10 16th December 2006 07:17 PM
Double bass reflex information Ilianh Multi-Way 26 28th February 2004 11:19 PM
Double Bass Reflex 1.5 way with W-871S PaulHilgeman Multi-Way 0 30th July 2003 03:24 PM

New To Site? Need Help?

All times are GMT. The time now is 10:24 AM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 16.67%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio