Infinite Baffle: Looking for advice re: Manufacturing an OEM 18" for IB Applications - 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 18th May 2006, 09:32 PM   #1
diyAudio Member
 
andrikos's Avatar
 
Join Date: Feb 2004
Location: Tucson, AZ
Default Infinite Baffle: Looking for advice re: Manufacturing an OEM 18" for IB Applications

Hello everybody,
I am working with a subwoofer driver manufacturer to build an OEM 18” driver for Infinite Baffle applications. This is not a full time endeavor for me nor am I in the ‘business’. I do have a day job and this is basically a side project for me. I’m not in it for the money, that’s why I expect to be able to offer the best $/liter displacement ratio in all of wooferdom. I’m doing it to prove to myself that I can do such a thing and in the process help the community use a driver that is specifically and exclusively designed for IB applications.


The main parameters we’re trying to hit by order of importance are:

Xmax > 20mm (more is obviously better but we’re also looking at linear, low distortion performance)
Fs < 20Hz
18” driver – Sd = 1400 – 1500cm^2. We feel that an 18” driver gives us the best chance of hitting our goals.
MAX SPL: >98dB at 10Hz, 110dB at 20Hz, 116dB at 30-80Hz unechoically per driver. Each doubling of driver number will add 6dB to this number. Room gain should add about 20dB more to the above numbers give or take, YMMV.

Pe = 500W single coil
Qts = 0.7- 0.8 (flat response for IB applications, not recommended for small enclosures sealed or ported).
Vas > 500 liters
Neodymium magnet
Foam surround (new and improved stuff not the foam from the 70’s and 80’s)

Our goal air displacement volume is >6 liters.
Our cost goal is <$50 per liter so as to have the most cost effective IB driver out there that is specifically designed for Infinite Baffle operations.

I do not care about aesthetics, bling factor etc. Every single cent will be dedicated towards PERFORMANCE! No fancy graphics/materials just to make a silly statement (i.e. this is NOT an automotive application focused driver )

This driver is aimed to DIY audiences that have the education, knowledge and experience to do a simple IB install with 1 or multiple of these drivers for UNPARALLELED bass performance.

For those who know IBs, the advantages are numerous and overwhelming:
1) Far lower cost than any commercially available subwoofer of an topology
2) Very simple structure (no fancy, expensive boxes required)
3) Out of sight, out of mind – High WAF
4) Did I mention the bass ROCKS? The house shakes, creaks and groans. Little children and puppies whimper in the corner. Neighbors file police complaints. You get the idea…
5) Perfectly blended and natural bass to the rest of your system.

Why am I writing this? Since I’m not a manufacturer, I would like the input of experienced IB owners and enthusiasts that are excited at the possibility of installing an Infinite Baffle in their home theater for a low cost. I’m a huge bargain shopper and the next step for me is to actually MAKE the drivers I want to buy. My potential ‘customers’ are NOT audiofools who spend $17k on a coffin sized sub with an undersized set of ports. My ‘customers’ are regular working stiffs like me with ‘real’ salaries and ‘real’ constraints because they need to include diapers and formula in their budget…

I hope my post wasn’t toooo long.
I’m looking for advice, desirable features, do’s and don’ts, lessons learned etc. etc.
I appreciate and thank you in advance for your feedback.

Andreas
  Reply With Quote
Old 19th May 2006, 12:38 AM   #2
AJinFLA is offline AJinFLA  United States
Banned
 
Join Date: Feb 2005
Location: Tampa
You might want to start here:
http://home.comcast.net/~infinitelybaffled/
http://ibsubwoofers.proboards51.com/

FYI, a driver with Sd 1400-1500cm^2 and a surround capable of over 20mm excursion, will be larger than 18".

anechoically speaking

AJ
  Reply With Quote
Old 19th May 2006, 03:27 AM   #3
diyAudio Member
 
andrikos's Avatar
 
Join Date: Feb 2004
Location: Tucson, AZ
Thanks AJ, you're right about the Sd part.
  Reply With Quote
Old 19th May 2006, 05:10 AM   #4
diyAudio Member
 
Join Date: Apr 2004
Location: Costa Rica
Send a message via AIM to johninCR Send a message via MSN to johninCR Send a message via Yahoo to johninCR
A pair of IB 15's will meet your performance requirements for only about $200. Also, Hawthorne Audio is coming out with an 18" cast frame driver built by Eminence specifically for IB. They're sticking with the pro heritage and going with the Definimax cloth surround, so Xmax is only 14mm, but over excursion shouldn't be a banging nightmare.
__________________
Everyone has a photographic memory. It's just that most are out of film.
  Reply With Quote
Old 19th May 2006, 05:08 PM   #5
Paul W is offline Paul W  United States
diyAudio Member
 
Paul W's Avatar
 
Join Date: Oct 2003
Location: North Georgia
One suggestion... Before latching onto a Neo magnet spec, have your OEM supplier quote both Neo and ceramic, and then check freight costs. Ceramic might give more "bang for the buck" in driver cost but, considering shipping costs, maybe not the best overall business decision. Look for the best tradeoff before you leap.

Just personal preference, but I'd go with a little lower Qts.
  Reply With Quote
Old 20th May 2006, 03:11 PM   #6
diyAudio Member
 
paulspencer's Avatar
 
Join Date: Sep 2003
Location: Melbourne, Australia
How about 15" versions? It makes sense to build in multiples of 2 so they can be push pull and transfer less vibration to the structure. A single 18" requires a more solid structure to prevent vibration problems than a pair of 15" drivers mounted in this way. Perhaps some price incentives to buy a number of drivers ...
  Reply With Quote
Old 22nd May 2006, 09:38 PM   #7
diyAudio Member
 
andrikos's Avatar
 
Join Date: Feb 2004
Location: Tucson, AZ
Thanks for the suggestions so far.
If this thing flies, we'll definitely go the 15" route.
  Reply With Quote
Old 23rd May 2006, 03:01 AM   #8
AJinFLA is offline AJinFLA  United States
Banned
 
Join Date: Feb 2005
Location: Tampa
There is plenty of competition in the 15" range.
The number of 18" neo subwoofers with over 20mm xmax - is one (that I am aware of). And it ain't cheap.
My only suggestion (other than a nice open basket) is an aluminum cone.

cheers,

AJ
  Reply With Quote
Old 23rd May 2006, 01:03 PM   #9
diyAudio Member
 
theAnonymous1's Avatar
 
Join Date: Feb 2004
Location: Anonymityville
A 15" driver is a lot more "application friendly", but if you use an 18" driver you will naturally end up with a lower Fs which is in my opinion the second most important spec of a IB sub, first being Qts.
  Reply With Quote
Old 24th May 2006, 02:52 PM   #10
diyAudio Member
 
andrikos's Avatar
 
Join Date: Feb 2004
Location: Tucson, AZ
The main reason 15" will be offered too is to offer more options to the end user.

If we can make a 21" ultra-woofer for extreme applications, we'll do that too.
  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
ESL in infinite baffle hugobors Planars & Exotics 9 15th March 2008 04:22 PM
is there a infinite baffle 12 and 15" subwoofer thread ? zuki Subwoofers 9 28th July 2006 11:43 AM
NEW Dayton 15" Infinite Baffle Subwoofer The Paulinator Swap Meet 0 3rd May 2006 02:27 PM
help w/ infinite baffle sub HIPCHECK Subwoofers 5 16th December 2005 12:19 AM
At what point is the baffle "infinite"? leadbelly Subwoofers 8 4th December 2004 04:32 PM


New To Site? Need Help?

All times are GMT. The time now is 12:30 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