GR Research Brute Speakers

Presb4 · « **on:** 3 Sep 2023, 03:53 pm »

I have poked around and did not see a thread dedicated to building the new GR Research Brute Speakers. Maybe this can fix that....

Presb4 · « **Reply #1 on:** 3 Sep 2023, 03:56 pm »

This is my first build of a DIY speaker kit. I received the drivers and the crossover components this week and the flat packs are still in the mail.
I started on the crossovers this weekend and have them mostly done and will finish the wiring once I have the cabinets built and I can determine the length of wire I need.

Presb4 · « **Reply #2 on:** 3 Sep 2023, 05:37 pm »

Picture of my completed crossovers

Presb4 · « **Reply #3 on:** 3 Sep 2023, 05:45 pm »

So I was going to use the Norez in the cabinets, but I am not sure if I should also use poly fill in addition to the Norez.
What have the other Brute builders done? Danny? Hobbs? little help on this would be appreciated.

Presb4 · « **Reply #4 on:** 3 Sep 2023, 09:25 pm »

I found this old post from 2017 talking about Norez and poly or fiberglass fill. Would this thinking still apply to the Brute? And location, fiberglass in behind the bass speaker only or also behind the mid range too?

Quote from: Danny Richie on 24 Jan 2017, 06:02 pm

When the cabinet wall resonances are reduced it allows you to hear the bass as it was intended without added box coloration. So the bass is much cleaner and tighter. Lower vocal ranges are much cleaner as well.

Typically we line the cabinets with it wall to wall for maximum effectiveness, but just covering the middle of each panel can be very effective.

Fiberglass or poly fill is then added for additional absorption and tuning of the box.

Hobbsmeerkat · « **Reply #5 on:** 4 Sep 2023, 02:51 pm »

Quote from: Presb4 on 3 Sep 2023, 05:45 pm

So I was going to use the Norez in the cabinets, but I am not sure if I should also use poly fill in addition to the Norez.
What have the other Brute builders done? Danny? Hobbs? little help on this would be appreciated.

Yes, we recommend using fiberglass or polyfill on top of the NoRez. We used about 2" layer of fiberglass to cover the walls and about 3-4" worth to fill in the mid/tweeter section.

Presb4 · « **Reply #6 on:** 9 Sep 2023, 02:57 am »

Thanks Hobbs.

Presb4 · « **Reply #7 on:** 9 Sep 2023, 04:43 am »

OK folks, I got some shop time after work today and started the glue up of the right speaker. Man, when Danny says this thing has lots of bracing, he is not joking!

So, I had read on this forum about how someone else had trouble with their first glue up when they tried it all in one go, and on their second speaker they glue up only the internals and then the exterior box second on a different day. I figured that made since so I was going with that plan as well. But the more I got into it, I grew concerned that if any of the bracing was just off a little, I would not be able to get the sides on the next day.

So, I pivoted mid glue up, changed plans and glued all parts except for the front baffle. In hindsight, I think this was the best plan as I did fight the fit up.
If I had waited to finish it tomorrow, I'm not sure I would have gotten it all together

I did not have anyone helping me and that was a mistake. Take my advice, have someone help you, 2 hands is not enough. A few wooden blocks and wooden mallet help fit things up. The CNC groves are very tight once the wood glue swells the wood joints a bit so you will need the mallet.

I used slow set wood glue; it had a working time of 20-30 mins. I feel this is a must as there is so much bracing it easily takes 30 mins to fit everything together, plumb it and clamp it.

Presb4 · « **Reply #8 on:** 9 Sep 2023, 05:28 am »

Here is the internal bracing before glue up.

Don't forget to drill this out before glue up, or you might wish you had later.

Presb4 · « **Reply #9 on:** 9 Sep 2023, 05:33 am »

All done except for the front baffle.
These right angle clamps really worked well to keep every thing square during assembly.

corndog71 · « **Reply #10 on:** 10 Sep 2023, 05:21 am »

Nice work!

Man, those things are chunky!

BrandonB · « **Reply #11 on:** 10 Sep 2023, 05:45 am »

Quote from: corndog71 on 10 Sep 2023, 05:21 am

Nice work!

Man, those things are chunky!

Solid!

Danny Richie · « **Reply #12 on:** 12 Sep 2023, 03:42 pm »

Great pics.

fre11111 · « **Reply #13 on:** 12 Sep 2023, 08:55 pm »

I love build pics. Great job.

corndog71 · « **Reply #14 on:** 13 Sep 2023, 05:28 pm »

Danny / Hobbs, any idea when more kits will be available?

Hobbsmeerkat · « **Reply #15 on:** 13 Sep 2023, 06:40 pm »

We just got the tweeters in Monday, we still need to measure and match them into pairs, we should have that done by the end of the week.

BrandonB · « **Reply #16 on:** 13 Sep 2023, 08:44 pm »

Any news on the next level speaker the Bully or Beast coming out?

fre11111 · « **Reply #17 on:** 13 Sep 2023, 08:51 pm »

Danny/Hobbs,

The Beast will be interesting how the MTM will be oriented to the woofer cabinet.

Frederick

Danny Richie · « **Reply #18 on:** 13 Sep 2023, 10:14 pm »

Quote from: BrandonB on 13 Sep 2023, 08:44 pm

Any news on the next level speaker the Bully or Beast coming out?

The Bully is next and we are just waiting on the test boxes to get here. This one should work out really well and be a real easy one to design a crossover for.

Danny Richie · « **Reply #19 on:** 13 Sep 2023, 10:15 pm »

Quote from: fre11111 on 13 Sep 2023, 08:51 pm

Danny/Hobbs,

The Beast will be interesting how the MTM will be oriented to the woofer cabinet.

Frederick

The MTM will be vertical and on the inside edge of the cabinet just like the TM in the Brute.