GR Research NX-Extreme


Looks like a helluva lot of speaker for the money, even if you need to put it together which sounds kinds fun. Anyone built a pair of these or heard them? 
mofojo

@maplegrovemusic , here are a couple of pointers about building a GR Research kit:

Glue: I recommend Titebond III Ultimate. It gives you longer "open" time before starting to harden than do Titebond Original and II. Use more glue than you think necessary; the MDF that the flat pack enclosures are made of soaks up glue. Use a small paint brush to spread the glue evenly (you can get a bag of small aluminum-handle brushes at Harbor Freight). After you tighten the clamps, wipe off the glue "squeeze out" with a damp sponge.

Clamps: I really like the Jorgensen Heavy Duty (1,000 lb.) clamps. Lowe’s has the best price I found: $21 for the 36" online (Lowe’s doesn’t stock them, but their shipping is free and fast). You’ll need at least four, more is better. If you want to spend less, Harbor Freight has some okay clamps that are really cheap.

Before gluing, do a "dry fit": assemble the enclosure, using masking tape to keep all the panels together. Looking at it assembled will help you think in an organized fashion. Once you apply the glue, a feeling of panic may overtake you! Prepare, think ahead, and remain calm. If this knucklehead can do it, so can you ;-) .

Read through as many "build" threads on the AudioCircle GR Research Forum as you can. You will learn how other guys went about their builds, the mistakes they made, and what they advise. You can ask them questions; Danny’s customers are a really great group of fellas!

As for finish, check out the black spray paint John Deere makes and markets (yeah, the tractor company!). It’s sheen is what’s called "Hot Rod Black" in the custom car world. Really cool, chicks dig it ;-) .

I have GRs OB doubles but bought drivers for a third one. I wished I would have gotten the 8 ohm versions, for doubles. Then the 370 watt amp would have a little more push 370 @ 4, and half that at 8. So pick your drivers too. If you go trips, I think you have to use th 16 ohm drivers.
Doubles you use to have an option, 16 8 or 4, use to be anyways..

As for building them, just a snap, great workmanship and QC is outstanding.. Everything was dry fitted and marked.. Jays a great guy...,
The whole bunch had a LOT of patience, I ASK QUESTIONS, always a speedy response, very professional..

I had a pair of LS6s, man did they need breathing room. lots of room..
6-8 feet from back wall, no wall behind you worked the best, ampa style
sure a different speaker, the way they work, pretty picky, pretty cool if you get it right. lots and lots of room treatment..Same with most speakers..
I got them second hand, and the builder did a great job. I'd love a pair of LS9s oh yea...Much better tweeter section. I'd love to hear a pair...I think Danny uses a pair for reference in his builds.. Alu, frame. The new ones are HDF or MDF

Regards..
Good point about the two different versions of the woofer @oldhvymec. Knowing I was going to build doubles (the 2-woofer version), I got myself the 8 ohm woofers rather than the 16 (the woofers actually measure 14 ohms and 7, I believe). Putting two of the "8" ohm woofers on the plate amp creates a little more output from the plate amp than do two of the 16 ohm (the plate amp behaving as do almost all solid state designs). Three of the 8 ohm woofers can NOT be used on one amp, as their combined impedance is too low.   

Oh, I neglected to comment on the 4 ohm version of the GR Research woofer. GR Research offers a 4 ohm woofer, but not for use in open baffle applications, only sealed and ported. The non-ob version has not been optimized for ob use, and the two are not interchangeable. So the non-ob woofer is available in 4 ohms only, the ob woofer in both 8 and 16 ohms, but not 4.

Another point: the GR Research 4 ohm woofer is exactly the same as the 12" woofer found in the Rythmik F12, except the GRR has a paper cone, the Rythmik an aluminum. Rythmik sells the F12 in a version with the paper cone woofer, model F12G. GR Research, being a company aimed at DIYers, offers the F12G as a kit only. You get the woofer and the Rythmik plate amp, and build the enclosure yourself. Or buy the version Jim Salk offers, with the F12 kit installed in an incredible box of Jim’s design and build. His enclosure has the best bracing I have ever seen!

Is everyone now thoroughly confused? ;-)

bdp246,377 posts03-15-2020 11:40pm

Oh, I neglected to comment on the 4 ohm version of the GR Research woofer. GR Research offers a 4 ohm woofer,

Yup there was an option or two. 8 or 16 ohm drivers 8 ohm drivers are louder, hows that? Also a sand filled DIY, too. There are some guys that will build the kits, finnish is always the spendy part. Emron, was a great paint, just the lead content was through the roof..and no breathing it at all.
We called it drop dead gorgeous, paint...
Jay the box and kit builder guy with GR, has the speakers the OP is referencing, (I think). he just loves um. Ask him, good guy.. Quality work from that guy...

Regards