Cheap drivers - 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 11th September 2009, 07:17 AM   #1
jerryo is offline jerryo  Isle of Man
diyAudio Member
 
Join Date: Jun 2007
Default Cheap drivers

I have got the chance to buy some "new" 12" bass drivers for 15.00 each with the following spec. Paper cone, double magnet;
3.2 ohm's
95 db/w
27.4 Fs
Qms 2.34
Qes 0.26
Qts 0.24
VAS 268 litre's
SD 514 cm squared

What do you think?
Sealed/Ported......... I thought that I would get 4 of them.
  Reply With Quote
Old 11th September 2009, 10:55 AM   #2
bjorno is offline bjorno  Sweden
diyAudio Member
 
Join Date: Mar 2005
Location: Jacobsmountain
Send a message via MSN to bjorno
Quote:
Originally Posted by jerryo View Post
I have got the chance to buy some "new" 12" bass drivers for 15.00 each with the following spec. Paper cone, double magnet;
3.2 ohm's
95 db/w
27.4 Fs
Qms 2.34
Qes 0.26
Qts 0.24
VAS 268 litre's
SD 514 cm squared

What do you think?
Sealed/Ported......... I thought that I would get 4 of them.
Hi Jerryo,

Looks like very good drivers. Although no x-max is given: At 1 W input using 4 of those drivers would surely shake my room wall if I had the opportunity to design suitable speakers.

I would build a Ht-woofer system comprising of 2 serial connected ported boxes in parallel with a T-TQWT driven by a ordinary sub bass amp.

Place the T-TQWT somewhere at the short room sides and the ported boxes spread out at both of the longer wall sides and test for best in room response.

If you aim for a isobaric or clamshell,minimum volume ported box using 4 drivers ,you could put them in the reflex box shown submitted, but the in room SQ will IMO be far below what's achievable with the T-TQWT and the 2 ported boxes.

PS: The T/S data is consistency checked using the HR input screens.

b
Attached Images
File Type: gif Jerry-O_T-TQWT.GIF (156.4 KB, 186 views)
  Reply With Quote
Old 12th September 2009, 06:32 PM   #3
jerryo is offline jerryo  Isle of Man
diyAudio Member
 
Join Date: Jun 2007
Hi bjorno,
thank you for your reply; yet again you have shown how generous you are with your time by answering questions posted by less informed people like myself.
From what you say these drivers will be a good buy so I will probably go ahead and get them.
I will have to accept certain design restrictions to placate my wife so compactness of the box will have to be considered.
Would I have any success with a ported isobarically loaded configuration? Isobarik just to reduce VAS if for no other reason.
I have no doubt that the ideas you relayed to me would be very, very good but at the moment I think they may be just a bit beyond my available time and circumstances.
Thank you again
Jerry
  Reply With Quote
Old 13th September 2009, 01:57 PM   #4
bjorno is offline bjorno  Sweden
diyAudio Member
 
Join Date: Mar 2005
Location: Jacobsmountain
Send a message via MSN to bjorno
Quote:
Originally Posted by jerryo View Post
..I will have to accept certain design restrictions to placate my wife so compactness of the box will have to be considered..
Hi Jerry,

Why not state your requirements on the speaker box dimensions from the beginning?

Quote:
..Would I have any success with a ported isobarically loaded configuration?..
Who knows but you?

Quote:
..Isobarik just to reduce VAS if for no other reason..
Jerry
Are you sure? : http://www.musicanddesign.com/Isobaric.html

b
Attached Images
File Type: gif Jerry-O_Isobaric.GIF (21.0 KB, 113 views)
  Reply With Quote
Old 13th September 2009, 06:15 PM   #5
jerryo is offline jerryo  Isle of Man
diyAudio Member
 
Join Date: Jun 2007
Hi bjorno,
that's an interesting study of isobaric loading; I wonder if anyone at Linn products has read it? I have found that isobaric loaded B139's produce some very deep and convincing bass. The distortion mechanism's mentioned are no doubt real but with the distortions of room acoustics they are probably not that important. But then i know nothing.
I do not know what size cabinet is going to be acceptable to my wife. I think perhaps I will never know until the speakers are placed into the room. I guess the phrase "as small as possible" would be on my wifes lips (as if that means anything)
I re-read some threads regarding "ripoles" recently and to be honest because of the simplicity of construction I might, just for the hell of it try them out. They do at least offer the smallest box configuration and if they don't work out as I imagine then not alot of material or time will have been wasted.
I can then move on upwards to more elaborate designs as necessary.
Cheers friend
  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
Cheap 6.5" drivers PeteMcK Multi-Way 42 1st January 2009 08:11 AM
Cheap little Sony Drivers Smokehouse Bob Full Range 9 30th January 2007 01:18 AM
WTB: 269-469 ("1$ Parts Express") drivers, or other really cheap FR drivers. Spasticteapot Swap Meet 1 5th November 2006 03:31 PM
Cheap un-known car drivers Matttcattt Multi-Way 7 25th June 2003 07:14 AM
drivers for cheap Iron Byron Swap Meet 0 27th August 2002 05:39 PM


New To Site? Need Help?

All times are GMT. The time now is 01:43 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