December 19th, 2019, 1:20 pm
December 21st, 2019, 3:54 pm
December 29th, 2019, 3:32 pm
mix4fix wrote:Looking for free. These speakers are not worth putting money into but are kept around.
On a side note, are those woofers or subwoofers?
January 2nd, 2020, 2:14 am
David McGown wrote: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.
January 2nd, 2020, 6:55 am
January 2nd, 2020, 4:26 pm
January 2nd, 2020, 5:56 pm
February 19th, 2020, 4:43 pm
mix4fix wrote:Anybody have an old pair of matching, functional 8 ohm 12 inch woofers (not subwoofers) laying around they can part with?
April 18th, 2020, 12:44 am
Stuart Polansky wrote: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.
RE OHMS 6.31
FS HZ 26.59
LE MH 1.49
MS GMS 71.80
CMS mm/N .4990
RMS NS/M 1.2367
VAS LTRS 189.11
XMAX MM 4.80
SD SCM 519.45
BL TM 13.13
EFF % .78
SPL dB 90.9