N3S Construction Photos

Ron · « **on:** 5 Jun 2011, 10:49 am »

Presently in the process of building a pair of GR Research N3S speakers with all the performance upgrade options including platinum bypass capacitors. The cabinets are finished in cherry veneer. The following are pictures showing the construction so far up to the point veneering the cabinets and cutting the holes for the drivers and Electra Tube input. The process I use to construct the cabinets is simple butt joints that are glued, clamped,and screwed. Thought the pictures might be helpful to those who want to build their own cabinets. I will add additional pictures when the crossovers are finished and installed inside the cabinets along with No-Rez and the drivers.

grimace · « **Reply #1 on:** 5 Jun 2011, 12:14 pm »

Looking great Ron. I will have to wire up my first N3 crossover soon, so a step-by-step picture tutorial would be awesome!

Thanks

minisq · « **Reply #2 on:** 5 Jun 2011, 05:30 pm »

I am contemplating add a pair of these to my HT...just not sure if i want these or the TL towers. From what i have read if i have a subwoofer, there is no need for the TL...so maybe i build a sealed tower.

Thanks for posting!!!

Ron · « **Reply #3 on:** 5 Jun 2011, 09:09 pm »

The following two photos were added to show the N3S low and high pass crossovers. One shows the component parts mounted to the crossover boards but not wired. The other photo shows the crossovers wired and the wires labeled. The component parts are secured to the boards with hot melt glue and plastic wire ties.I made the boards from MDF, 4-1/4" W x 5-1/4" W x 1/4" Thk. The low pass filters will be located on the top side of the upper brace inside the speaker and the high pass filter will be located on the bottom side of the lower brace.

dvenardos · « **Reply #4 on:** 6 Jun 2011, 02:25 am »

Thanks Ron!

When I get caught up on my audio projects this is next.

Ron · « **Reply #5 on:** 15 Jun 2011, 11:59 am »

Attached are some pictures showing the final assembly phase of my N3S. Only thing left to finish are the magnetic grill frames.

Picure No. 1 shows the No-Rez and crossovers installed. The No-Rez needs to be from 1-1/4" -
1-1/2" away from the back side of the front baffleboard. The low pass crossover is mounted on top of the upper brace and high pass crossover is mounted under the lower brace secured with #6 x 1" long sheet metal screws.

Picture No. 2 shows the Dacon Poly-Fil which is used to lightly fill the area behind the woofers and
tweeter.

Picture No. 3 shows the drivers installed.

Picture No. 4 is a rear view of the cabinet showing the Electra Tube input connectors installed.

The N3S have a very detailed, natural, and open sound quality with excellent sound stage imaging and depth. The N3 TL towers has better bass below 65 hz than the N3S due to it's transmission line loading, but above 65 hz they sound identical. The N3S definitely needs a good subwoofer like the GR Research servo subwoofer to cover the bottom octive of bass.

jeffh · « **Reply #6 on:** 15 Jun 2011, 01:03 pm »

Quote from: Ron on 15 Jun 2011, 11:59 am

Attached are some pictures showing the final assembly phase of my N3S. Only thing left to finish are the magnetic grill frames.

Ron, could you please post some detailed pictures of how you build your speaker grills. I have tried
this a couple of times with not so good results. I would like to see how an expert does it.

Jeff

NeilT · « **Reply #7 on:** 15 Jun 2011, 02:26 pm »

PM sent

Ron · « **Reply #8 on:** 15 Jun 2011, 02:36 pm »

I will be working on the grills this weekend, so I will take some detailed pictures and post them for you when I finish.

bprochford · « **Reply #9 on:** 15 Jun 2011, 02:50 pm »

Hi Ron,
Are you cutting the driver holes in your veneer with a flush trim bit, or by hand with a blade? Or is there an even better method that you use? I'm about to veneer my N3 towers and would love to know the best technique for cutting these holes once the veneer is applied.
Thanks,Brad

chronicali · « **Reply #10 on:** 15 Jun 2011, 06:24 pm »

I'll be waiting for the grill build too, I need to make some grills as well.

jeffh · « **Reply #11 on:** 15 Jun 2011, 09:02 pm »

Quote from: Ron on 15 Jun 2011, 02:36 pm

I will be working on the grills this weekend, so I will take some detailed pictures and post them for you when I finish.

Thanks Ron. Specifically, any advice on installing the grill cloth. That is where I seem to be having the most trouble. How do
you glue it? What type of glue? How do you deal with the wrinkles at the corners, etc... What are the tricks of the trade?

Also any details on how you line up the magnets to make sure the grills sit in exactly the correct spot. Mine seem to
want to move a little.

Ron · « **Reply #12 on:** 15 Jun 2011, 11:10 pm »

1. I cut the holes for the drivers after I have veneered using a Jasper circle cutting jig on my router and a 1/4" straight cut bit. Some people like to cut the holes before veneering, but I prefer to do it after veneering. The only thing is that you have be careful and pay attention to what you are doing.

2. Making the grill frames and covering them with grill cloth can be a real challenge. When covering the grill frame with the grill cloth I normally cut the cloth about 1-1/2 inches oversize on all four sides. Spray the back side of the grill frame with 3M brand No. 77 spray adhesive. Allow to dry about 5-10 minutes. Lay the grill frame face down on the cloth and start pulling the cloth over the back of the frame one side at a time. To eliminate the wrinkes you have to stretch the cloth tight. Using a clothes iron on medium heat also seems to help to get the wrinkes out. Use a sharp utility knife or rotary cutter to trim the grill cloth.

To line up the magnets, I first drill 1/8" diameter holes at all four (4) corners of the frame. Lay the frame on the front of the speaker baffle and position the frame centered squarely and evenly over where the drivers will be located. Insert a small nail down through each of the four (4) holes and tap with a hammer to mark the location on the front of the baffle board. Remove the grill frame and drill 1/4" diameter holes through each of the four (4) pilot holes and the matching four (4) locations on the front baffle board. Install 1/4" Dia. x 1/4" long neodymium magnets in each of the four (4) holes on the baffle board using a small amount of wood glue and tapping in with a hammer. Install magnets in the grill frame in like manner making sure the polarities match up so they attract the ones on the baffle, not repel.

Hope this helps answer your question.

tesseract · « **Reply #13 on:** 16 Jun 2011, 04:58 pm »

I'm sorry if I have missed this. Is the XO, in particular the BSC, the same for the sealed as the transmission line?

Ron · « **Reply #14 on:** 16 Jun 2011, 07:11 pm »

The crossovers for both the sealed and transmission line version are the same.

Ron · « **Reply #15 on:** 22 Jun 2011, 08:52 pm »

For those that asked about pictures of the grill construction for the N3S, I still haven't finished them because of working on other priority jobs. I do have a detail drawing for constructing the grills. Since it is in a PDF format, I can't attach it to this link, but if you send me a PM with your email address I will be glad to send it to you.

Saturn94 · « **Reply #16 on:** 4 Jul 2011, 12:40 am »

Great job Ron (as usual)!

Hope you are doing well.

Ron · « **Reply #17 on:** 10 Jul 2011, 12:37 am »

Finally got around to finishing the grills for my N3S. I enjoy building speakers,but not the grills. They can be a pain in the butt to do. Overall I am pleased with how everything turned out. They sound great especially with the platinum bypass caps. Attached pictures show how they look with the grills on and with them off.

mcallister · « **Reply #18 on:** 10 Jul 2011, 11:38 am »

Looks great as usual Ron! Are you selling this pair?

Ron · « **Reply #19 on:** 10 Jul 2011, 11:54 am »

Hi Mike. Thanks for the compliment. I might sell them if anyone is interested in buying them. How are your N3S doing?