DCAudioDIY.com

DC Area Audio DIYer's Community
It is currently October 26th, 2020, 9:21 am

All times are UTC - 5 hours [ DST ]




Post new topic Reply to topic  [ 19 posts ]  Go to page 1, 2  Next
Author Message
PostPosted: December 11th, 2019, 3:05 am 
Offline

Joined: June 22nd, 2013, 11:00 am
Posts: 818
Anybody have an old pair of matching, functional 8 ohm 12 inch woofers (not subwoofers) laying around they can part with?


Top
 Profile  
 
PostPosted: December 11th, 2019, 11:51 am 
Offline
User avatar

Joined: July 24th, 2015, 4:17 pm
Posts: 1274
Location: Parkville, Maryland
mix4fix wrote:
Anybody have an old pair of matching, functional 8 ohm 12 inch woofers (not subwoofers) laying around they can part with?


I have a pair of Altec 15-inch woofers. They're yours for $500.

_________________
Walt


Top
 Profile  
 
PostPosted: December 11th, 2019, 11:53 am 
Offline

Joined: January 14th, 2015, 11:15 pm
Posts: 383
I don't have any but I think it would help if you let us know how you plan to use them.

Ray


Top
 Profile  
 
PostPosted: December 11th, 2019, 1:08 pm 
Offline

Joined: June 22nd, 2013, 11:00 am
Posts: 818
To fix a pair of crappy, old pair of speakers.


Top
 Profile  
 
PostPosted: December 11th, 2019, 1:11 pm 
Offline

Joined: February 28th, 2013, 1:19 pm
Posts: 484
https://www.parts-express.com/cat/woofe ... PortalID=1


Top
 Profile  
 
PostPosted: December 12th, 2019, 9:29 am 
Offline
User avatar

Joined: December 14th, 2013, 2:19 pm
Posts: 800
Are you looking for freebies, or are you paying?

If you are paying, I have a pair of new, in the original box, custom Eminence 12" woofers.

Here are the T-S parameters, if they work for you.

They sound excellent in the right enclosures.

$100 each.

RE OHMS 6.31
FS HZ 26.59
LE MH 1.49
MS GMS 71.80
QM 9.70
CMS mm/N .4990
QE .440
RMS NS/M 1.2367
QT .420
VAS LTRS 189.11
XMAX MM 4.80
SD SCM 519.45
BL TM 13.13
EBP 60.5
EFF % .78
SPL dB 90.9


Attachments:
Smaller-Collage.png
Smaller-Collage.png [ 1.92 MiB | Viewed 4654 times ]
Eminence.jpg
Eminence.jpg [ 1.44 MiB | Viewed 4654 times ]
Top
 Profile  
 
PostPosted: December 12th, 2019, 5:43 pm 
Offline

Joined: June 22nd, 2013, 11:00 am
Posts: 818
Looking for free. These speakers are not worth putting money into but are kept around.

On a side note, are those woofers or subwoofers?


Top
 Profile  
 
PostPosted: December 12th, 2019, 6:47 pm 
Offline
User avatar

Joined: December 14th, 2013, 2:19 pm
Posts: 800
Woofers.


Top
 Profile  
 
PostPosted: December 18th, 2019, 9:22 pm 
Offline

Joined: June 22nd, 2013, 11:00 am
Posts: 818
David McGown wrote:
https://www.parts-express.com/cat/woofers/15?N=19809+4294967118+4294965103&Ne=10166&Nrs=collection%28%29%2Frecord%5Bendeca%3Amatches%28.%2C%22P_PortalID%22%2C%221%22%29+and+endeca%3Amatches%28.%2C%22P_Searchable%22%2C%221%22%29%5D&PortalID=1


What is the difference in brands and models?


Top
 Profile  
 
PostPosted: December 19th, 2019, 1:16 pm 
Offline

Joined: February 28th, 2013, 1:19 pm
Posts: 484
That is a complex question, and depends on the speaker impedance (nominal), sensitivity, enclosure size and alignment you are putting the driver into. You need different types of drivers depending on whether it is a sealed box or vented box. It is relatively easy to fit a replacement woofer to sealed enclosure, but much more difficult with an vented box enclosure, since the port size and length (tuning) becomes a big factor speaker.

You want to look at the Thiele-Small parameters of the driver as a rough guide.

Typically, a sealed box woofer is going to have a Qts between 0.4 to 1.0
A vented box woofer typically will have a Qts below 0.4.

The higher the Qt parameter, the weaker the motor, and ability to control the driver at resonance (Fs). The driver will have a peaking low frequency response (boomy).

I would tend to avoid drivers with a high Qts (above 1.0), but unfortunately, that eliminates many of the cheapest drivers listed such as the GRS or Golldwoods

If you are looking for a cheap sealed box 12" driver, the GRS 125FPC-B (Square frame) or Goldwood GW-1244 (4 ohm) or GW-1248 (8 ohm) might fit the bill for inexpensive replacement drivers. They both have Qts around 0.7, which indicates moderate LF peaking (loss of control) which will give the impression of more extended bass.

For a vented box, difficult to advise. The Dayton DC300-8 might work, but have to know more about the enclosure and port size and length to see how it could be made to work. It is not easy to try to match and requires calculation. It might be better to convert the vented box into a sealed box enclosure to make things simpler.

The unfortunate fact of life is to get better or have more choices will cost more money, and is probably not worth it for a cheap pair of speakers. Close enough may be all that is affordable.

David


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 19 posts ]  Go to page 1, 2  Next

All times are UTC - 5 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 10 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group