Get your questions answered from other customers
who own this product or have experience with it.
If your question requires design or troubleshooting information,
please email firstname.lastname@example.org
for a prompt reply.
GRS 12PF-8 12" Paper Cone Foam Surround Woofer
What is the diameter between mounting holes? Thank you.
I was disappointed to find that there were actually 6 holes when indeed the pictures posted show 8. I have an 8 hole mount and it appeared it was a "drop in" replacement. Not so. And yes, it's a big deal when you're up off the floor 25 feet only to find this out.
Date published: 2012-10-17
I plan on using this in a ported alignment under a bed for moderator listening and mostly sounds FX.I understand this device works better with a sealed enclosure about 3.0 cu.ft., but is there any smaller configuration possible? This would include porting and sealed boxes.
Thiele/Smalle specifications determine if a driver is suitable for porting, sealed or both. And typically, even if both - one is better that the other. This driver was built and designed for sealed enclosures. If you plug the numbers into a box calculator - you will find that the specs for a ported box don't make sense. That is because the driver specs don't support that configuration. As for size of sealed box... that same calculator will show you response curves for various box sizes. .707 total Qts delivers razer flat response. 1.0 has a bump in the lower mid-bass, and .5 is critically accurate - often used in esoteric audiophile systems.
Date published: 2012-09-14
can i put this 12 inch sub in a 1.38 cubic feet sealed box and it still sound nice??
You need to take the specs (theile-smalle parameters) and plug them into an "online box calculator". It will then tell you the volume and tuning for a ported enclosure. You'll see response curves and the 3db down point for bass response. You will also see the same for a sealed box. Specify a total Qts of .707 for the most accurate bass. I can't use the adjective "nice" - but can say that if you use this method - that you will get optimum performance from this driver.
Date published: 2012-09-28
Is it possible to get a full set of thiele-small parameters for this driver? I am specifically looking for Bl and Sd figures.
Unfortunately the manufacturer does not specify what these figures are. However, my modeling program gives me an Sd of 494.6 sq cm and a BL factor of 6.197 Tm. These are based on the rest of the parameters and calculated via BassBox.
Date published: 2013-06-20
Internal Cabinet Size?
what size cabinet would these need if they are inside a sealed cabinet? Also what cross-over frequency should you use when paired with a GRS 8PF-8 and Dayton Audio DC28F-8?
Great price speaker but not much else. This unit needs a large sealed box, infinite baffle or dipole use.because of its high Qts or total Q. Because the x max is only 3 mm you will need several of them. Remember a doubling of x max will give you 6 db more output. Also remember that 87 db efficiency is low. Every 3 db increase in efficiency will require an amp 1/2 the size. Each time you doudle the number of drivers you get a 3 db increase in efficiency for the same power. This is very important because as a voice coil heats up you get dynamic compression. I can only recommend this driver in multiples. I would recommend at least 4 per channel for 93 db efficiency. Good luck Ralph
Date published: 2012-04-30
can you put the grs 12'' with the grs 8'' and the Goldwood GT-510 tweeter in the same sealed box
I was wondering if you could put the GRS 12PF-8, GRS 8PF-8, and the Goldwood GT-510 tweeter in the same sealed box with an internal volume of 3.295 cubic feet and the sound not be distorted at all.
Tweeters and most mids have sealed backs. Drivers that have open backs need to have their own chamber - volume designed to match their specs. So no, you can't put the 12 and the 8 in the same air space. Each air space needs to be determined by taking the specs and using an online speaker box calculator.
Date published: 2012-09-28