3-Way Cabinet Question - diyAudio
Go Back   Home > Forums > Loudspeakers > Multi-Way

Multi-Way Conventional loudspeakers with crossovers

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 20th May 2005, 09:09 PM   #1
diyAudio Member
 
Join Date: Apr 2005
Location: NH
Send a message via AIM to 69stingray Send a message via MSN to 69stingray Send a message via Yahoo to 69stingray
Default 3-Way Cabinet Question

If I build a small 3-way speaker, do I need to seperate the woofer from the midrange and the tweeter or can they use the same volume? How does that effect the volume calculations for the cabinet? I am thinking about a 8" woofer, 5" mid and a 1" tweeter. I would like the 8" F3 to be under 40 Hz.

Thanks.
__________________
Audio DIY Page
FOLLOWMY529.COM - Subscribe and follow the performance of my daughter's 529 College Saving Account.
  Reply With Quote
Old 20th May 2005, 09:18 PM   #2
diyAudio Moderator
 
pinkmouse's Avatar
 
Join Date: Apr 2002
Location: Chatham, England
Hi Zach

Yes, in general, each driver needs to have it's own volume. However, 99% of tweeters, and some mids, have a sealed back design.

What drivers are you thinking of using, and how big can the box be?
__________________
Rick: Oh Cliff / Sometimes it must be difficult not to feel as if / You really are a cliff / when fascists keep trying to push you over it! / Are they the lemmings / Or are you, Cliff? / Or are you Cliff?
  Reply With Quote
Old 21st May 2005, 03:55 AM   #3
diyAudio Member
 
Join Date: Apr 2005
Location: NH
Send a message via AIM to 69stingray Send a message via MSN to 69stingray Send a message via Yahoo to 69stingray
Thank you for the quick reply.

The goal of this project is to build a pair of 3-way that are a similar size of some really old, really poor quality speakers my father-in-law currently has.

They measure 13" wide x 11.25" deep x 21.25" tall, which, when using 3/4" MDF, results in approx. an internal volume of 1.44 ft3 or 40 L

I started looking at the Dayton 8" Woofer (Vas = 2.04 ft3, Fs: 29 Hz, 88 SPL, 29-3,000 Hz, Xmax= 4.5 mm, Qts: 0.38, Qms=3.23 & Qes: 0.44

The Dayton 8" looks interesting because they are inexpensive, have a low freq. range and are inexpensive.

Playing with WinISD, a volume of 30L gets a F3 of 33 Hz

Keeping the same width and depth, after the 30L, I have only have about 7 inches of height to use for midrange and tweeter, assuming that I made two different volumes inside the cabinet.

What inexperience options to I have for sealed 5" midranges? I do not have my catalog around, but they usually describe the speaker as sealed? I plan on buying a 3-way cross-over with 375 & 3,000 cut-offs.

What happens if a 8" and a 5" midrange share the same volume?
__________________
Audio DIY Page
FOLLOWMY529.COM - Subscribe and follow the performance of my daughter's 529 College Saving Account.
  Reply With Quote
Old 22nd May 2005, 09:06 AM   #4
AndrewT is online now AndrewT  Scotland
diyAudio Member
 
Join Date: Jul 2004
Location: Scottish Borders
Hi,
an unsealed mid range will face the pressure from the bass pushing or pulling the mid cone away from central position.
Mid range cones usually have a small Xmax and so distortion will be very noticeable in the mid when bass is working, particularly at low frequency.
Are sealed mids common?
__________________
regards Andrew T.
  Reply With Quote
Old 22nd May 2005, 09:45 AM   #5
diyAudio Moderator
 
pinkmouse's Avatar
 
Join Date: Apr 2002
Location: Chatham, England
Quote:
Originally posted by AndrewT
Are sealed mids common?
Morel do a reasonable dome mid that's sealed, and I think Vifa do one as well. Of course there is the ATC, but just one would cost more than the entire rest of the system!

The box size for the mid can be quite small for your planned crossover point, just model a few drivers and box sizes to give a smooth roll of at about 300Hz. It might well be as small as 1/2 a litre or so.
__________________
Rick: Oh Cliff / Sometimes it must be difficult not to feel as if / You really are a cliff / when fascists keep trying to push you over it! / Are they the lemmings / Or are you, Cliff? / Or are you Cliff?
  Reply With Quote
Old 22nd May 2005, 09:55 AM   #6
frugal-phile(tm)
diyAudio Moderator
 
planet10's Avatar
 
Join Date: Oct 2001
Location: Victoria, BC, NA, Sol III
Blog Entries: 5
Quote:
Originally posted by AndrewT
Are sealed mids common?
Certainly they were very common... i have a ton of them lying around here. I'm not a big fan of them, but they are very common in older 3-ways (and Tom Danley had closed backs built for his unity horn.

dave
__________________
community sites t-linespeakers.org, frugal-horn.com, frugal-phile.com ........ commercial site planet10-HiFi
p10-hifi forum here at diyA
  Reply With Quote
Old 22nd May 2005, 02:35 PM   #7
diyAudio Member
 
Join Date: Apr 2005
Location: NH
Send a message via AIM to 69stingray Send a message via MSN to 69stingray Send a message via Yahoo to 69stingray
Thanks for the replies everyone. I will look at the sealed midranges, I will also model some box sizes. This is my first non-subwoofer project so I don't want to spend to much on speakers--just in case the reasults are up to par!
__________________
Audio DIY Page
FOLLOWMY529.COM - Subscribe and follow the performance of my daughter's 529 College Saving Account.
  Reply With Quote
Old 23rd May 2005, 01:31 AM   #8
jamesj is offline jamesj  New Zealand
diyAudio Member
 
Join Date: Jul 2004
Location: Middle Earth
Why not just build a separate chamber within the box for the midrange unit? The box you are planning to build will realise 40L and you need only 30L, so there's plenty of scope. A vertical partition between a shelf-brace and the top of the cabinet will work just fine. The extra volume behind the mid will provide more space for fill than any enclosed mid driver could muster for effective absorption of the back wave.

James
  Reply With Quote
Old 23rd May 2005, 01:42 AM   #9
frugal-phile(tm)
diyAudio Moderator
 
planet10's Avatar
 
Join Date: Oct 2001
Location: Victoria, BC, NA, Sol III
Blog Entries: 5
Quote:
Originally posted by jamesj
40L and you need only 30L
Or use the 10L to build a little folded aperiodic TL.

dave
__________________
community sites t-linespeakers.org, frugal-horn.com, frugal-phile.com ........ commercial site planet10-HiFi
p10-hifi forum here at diyA
  Reply With Quote
Old 23rd May 2005, 02:03 AM   #10
RJ is offline RJ  United States
diyAudio Member
 
Join Date: Oct 2004
There is a project out there already that''l fit your design goals and pocket book.
http://www.partsexpress.com/projects...ilee/index.htm

Although the Jubillees are in a 40 litre box it'll work just as well in a 35 litre box. The port might have to be re-worked on in WinIsd.
  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
Question on building a speaker cabinet GuitarDudeSRV Multi-Way 1 10th June 2007 09:59 PM
Ariel cabinet question andrew01 Multi-Way 5 1st April 2006 09:38 AM
Quick woodworking cabinet question.. Skitch72 Multi-Way 7 18th January 2006 07:15 PM
Cabinet question zincman Full Range 5 18th June 2005 09:51 AM
Cabinet question ? jim Multi-Way 3 7th January 2004 01:50 PM


New To Site? Need Help?

All times are GMT. The time now is 06:51 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