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

Multi-Way Conventional loudspeakers with crossovers

Surround less, spider less, mid bass driver
Surround less, spider less, mid bass driver
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 4th July 2014, 02:25 AM   #11
CLS is offline CLS  Taiwan
diyAudio Member
 
Join Date: Jun 2005
Location: Taiwan
I don't get it, either.

When the stroke is larger than a certain degree, the cone should be suspended at least at 2 positions to maintain the axial motion. That supresses the possible rocking to a minimum. And that degree of stroke might be still pretty small, I guess.

The suspensions should provide compliance and damping in a linear (or preditable) way. One of them should be air tight as the cone.

Er... those are just driver 101. Sorry.

So I can't visualise a successful driver without surround. Unless it's a whizzer cone and we ignore all other parts.

I vaguely remember, years ago, there's a Japanese big company providing products of surround-less woofer(s) on their high end boombox (or the likes). It's working like a sliding piston in a cylinder. And it was even promoted by its ability of long stroke. (small diameter, that is)

Now I can't even find it on google.
  Reply With Quote
Old 4th July 2014, 02:35 AM   #12
Andrew Eckhardt is offline Andrew Eckhardt  United States
diyAudio Member
 
Join Date: Nov 2005
Unfortunately the surround does more than suspend. It also damps bell mode resonance. Multiple parallel driven coils at the perimeter (in addition to apex coil) would be better. The logical end of progression would be a massively arrayed setup with a small drive coils/EM suspension/and cone areas. At that point you'd find that it isn't necessary to have them all totally isolated. A segmented radiating area with high damping links between them would be enough, or better, depending on how you wanna look at it...
  Reply With Quote
Old 4th July 2014, 02:39 AM   #13
sreten is offline sreten  United Kingdom
R.I.P.
 
Join Date: Nov 2003
Location: Brighton UK
Hi,

Us old farts know nothing, go with the clueless enthusiasts.

The outer aluminium ring is very poor cone termination,
it will work for bass, but won't work for good midrange.

Its telling the driver is always shown horizontal, its
obvious it won't work well vertical, as it has to.

Ferrofluid has been tried in bass units and it doesn't work,
and that is fitted with standard surrounds and spiders.

Any driver needing a separate supply needs to be great
to succeed, with no issues, I really can't see that here.

FWIW the issues of interaction of magnetic and suspension
linearity have been well covered previously, so here all you
are getting is a claim of an offering of something ideal.

Something us old farts have seen a lot of in our time,
different, unless really good, hardly ever means better.

rgds, sreten.

Not that I'm that old, but I might as well be.

Last edited by sreten; 4th July 2014 at 02:55 AM.
  Reply With Quote
Old 4th July 2014, 02:41 AM   #14
IG81 is offline IG81  Canada
diyAudio Member
 
IG81's Avatar
 
Join Date: Feb 2008
Quote:
Originally Posted by CLS View Post

I vaguely remember, years ago, there's a Japanese big company providing products of surround-less woofer(s) on their high end boombox (or the likes). It's working like a sliding piston in a cylinder. And it was even promoted by its ability of long stroke. (small diameter, that is)

Now I can't even find it on google.
Fostex "edge-less" woofer perhaps?

https://www.google.ca/search?site=&s...30.bPdNvzGp_IQ
  Reply With Quote
Old 4th July 2014, 03:13 AM   #15
sreten is offline sreten  United Kingdom
R.I.P.
 
Join Date: Nov 2003
Location: Brighton UK
Hi,

Said boombox used a long voice coil former with two back
to back spiders for linearity and a "surroundless" cone
on one end and a typical magnet system the other.

The edge of the cone had a quadrant section which very much
looked like white felt to me, that skimmed the cylinder it was in.

Fine for bass, rubbish higher up, but it was a sub.

5" (effectively bigger) in a 6" tube about 20" long I recall.

I also recall 4th order bandpass and a window
where you could see the gubbins of the driver.

rgds, sreten.

Last edited by sreten; 4th July 2014 at 03:38 AM.
  Reply With Quote
Old 4th July 2014, 03:34 AM   #16
Inductor is offline Inductor  Portugal
diyAudio Member
 
Inductor's Avatar
 
Join Date: Feb 2006
Location: Cascais
Nice. Congratulations, the first step is the more important. Hope you stay in business... after a few years (already two for the count/development.) Is it a FR(extended range)? Is it possible to post a complete set of T/S parameters (maybe later in time) with freq. output curves. Patents are very expensive (price and layers) and only interesting if someone is producing them (factory/speakers drivers) or licensing the technology. I bet all the good manufacturers like B&W, B&O and others are interested. You can start with trademarks today, they are very cheap comparing.

It makes me think of Romy the Cat with the Mitsubishi Diatone P-610 and leather suspensions and the Atelier Rullit (some links below, please feel free to compare them, goods and bads.)
Atelier Rullit
http://www.analog-forum.de/wbboard/b...er-gebraucher/
DIATONE ƒXƒs[ƒJ[ƒ†ƒjƒbƒgˆę—— ƒ_ƒCƒ„ƒg[ƒ“ ƒ_ƒCƒAƒg[ƒ“
GoodSoundClub - Romy the Cat's Audio Site - Forget the Diatone ? the leather suspension is the key interest.
  Reply With Quote
Old 4th July 2014, 03:54 AM   #17
jcarr is offline jcarr  United States
diyAudio Member
 
Join Date: Jul 2002
Location: Tokyo, Japan
Pioneer made what it called "edge-less" woofer units, such as the one used in the S-LH5 here:

Pioneer S-LH5

hth, jonathan carr
__________________
http://www.lyraconnoisseur.com/, http://www.lyraaudio.com
  Reply With Quote
Old 4th July 2014, 04:24 AM   #18
thoriated is offline thoriated  United States
diyAudio Member
 
Join Date: Nov 2003
Location: flyover country
The problem I've heard with ferrofluid in bass drivers is that it tends to be thrown out of the gap during long excursions with high accelerations. Ferrofluid may work better in an underhung VC configuration where it has less opportunity to 'escape'.
__________________
Art is nothing without science; science is nothing without philosophy.

Last edited by thoriated; 4th July 2014 at 04:28 AM.
  Reply With Quote
Old 4th July 2014, 07:03 AM   #19
Jef Nuyts is offline Jef Nuyts  Belgium
diyAudio Member
 
Join Date: Jan 2013
@ indicator

Very interesting of what you say about trademarks. I will take a close look at it.

I will this evening reply to the other questions.

Take care
  Reply With Quote
Old 4th July 2014, 10:00 AM   #20
Inductor is offline Inductor  Portugal
diyAudio Member
 
Inductor's Avatar
 
Join Date: Feb 2006
Location: Cascais
Take care.
  Reply With Quote

Reply


Surround less, spider less, mid bass driverHide 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
Choosing a driver for an OpenBafle mid-bass Eldam Multi-Way 13 23rd May 2014 11:32 AM
What Bass/Mid-bass driver for me? timreeves Multi-Way 4 17th March 2011 01:09 AM
Best driver for Mid Bass SETorbust Multi-Way 6 26th February 2011 06:57 PM
in need of recommendation for a mid-bass driver piro Multi-Way 4 4th June 2004 09:06 AM
Spider and surround creep capslock Multi-Way 1 30th November 2002 01:33 PM


New To Site? Need Help?

All times are GMT. The time now is 11:20 AM.


Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 14.29%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio
Wiki