New NX-Otica MTM section only

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AKLegal

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Re: New NX-Otica MTM section only
« Reply #40 on: 8 Oct 2016, 04:34 pm »
Hey Danny, I forgot to ask what the impedance is on these.

Danny Richie

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Re: New NX-Otica MTM section only
« Reply #41 on: 9 Oct 2016, 03:16 pm »
8 ohms nominal impedance.

Captainhemo

Re: New NX-Otica MTM section only
« Reply #42 on: 31 Dec 2016, 12:01 am »
Any progress on your build Alfred ?

jay

aceinc

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Re: New NX-Otica MTM section only
« Reply #43 on: 6 Feb 2017, 11:04 pm »
Captainhemo, What is the feasibility of producing the flat pack in all solid hard wood? If not completely in 3/4" planks, how about the small < 11-1/2" pieces in solid wood, and the large piece in veneer (either ply or mdf) to match the hard wood?


Captainhemo

Re: New NX-Otica MTM section only
« Reply #44 on: 7 Feb 2017, 02:14 am »
Captainhemo, What is the feasibility of producing the flat pack in all solid hard wood? If not completely in 3/4" planks, how about the small < 11-1/2" pieces in solid wood, and the large piece in veneer (either ply or mdf) to match the hard wood?
It would likely be far more cost efective to use the  curent flat packs  and have them laminated after assembly.  I'm not saying it can't be done but  hardwood is expensive and it  can  be more prone to resonence
Do you have a particular  type of wood in mind ?

jay

mlundy57

Re: New NX-Otica MTM section only
« Reply #45 on: 7 Feb 2017, 03:39 am »
It would likely be far more cost efective to use the  curent flat packs  and have them laminated after assembly.  I'm not saying it can't be done but  hardwood is expensive and it  can  be more prone to resonence
Do you have a particular  type of wood in mind ?

jay

Jay,

Something to keep in mind about hardwood is that it comes in varying size boards, not sheets like MDF. You would have to joint the edges flat and square so you can glue the pieces up into panels of the size you need, keeping grain pattern in mind for flow to adjacent pieces. Then the panels will have to be planed to a uniform thickness.

The width of the panels is going to be limited to the width of the planer which is going to be somewhere between 12" and 25" (my planer is 15"). The only way to get panels wider than the planer is to glue up multiple individual panels to the width of the planer and glue these panels together. Then you have to use hand planes to flatten, smooth and thickness the large panel to it's final dimensions.

Since the widest piece of the MTM Otica is the big wing at 20" you could do it with access to a 24" planer. Again be careful about grain direction. You would want it to match as it wraps around the big wing, baffle and small wing.

Another issue with solid wood to keep in mind is movement. Solid wood is not stationary. It expands and contracts with seasonal moisture variations. This movement occurs across the grain. To make the cabinet look right the grain would be oriented vertically. That would mean the expansion and contraction would occur across the width of the piece. Being glued to the base the bottom would be constrained but the top would be free to move. This would likely cause the wood to crack. One way around this would be to screw the wings and baffle to the base in such a way the bottom could expand and contract.

Another option would be to use a wood that doesn't expand or contract much. Usually that means quartersawn lumber. The issue is that the grain pattern on most quartersawn lumber is rather blend. For the most part, the really pretty grain patterns occur in flatsawn lumber but flatsawn tends to move the most in response moisture. There are exceptions to everything though. Highly figured quartersawn white oak is stunning while flatsawn mesquite is very stable.

As for resonances, at least with the MTM version, I wonder how much of an issue it would really be given how open the design is only the big wing should be affected and it has NoRez on the inside.

I'm not saying it can't be done, just that there is a lot more to doing it and making the end product look right than most people realize.

Mike

Captainhemo

Re: New NX-Otica MTM section only
« Reply #46 on: 7 Feb 2017, 04:29 am »
hey Mike
Yeah, all valid points and exactly why I said  much more cost effective to  build an MDF pair and veneer them. I used to build  some  projects out of solid Ash and many of them had a lot of laminating/joinery to build panels, it's a lot of work.

As you mentioned, the grain would have to run vertically so the large wing would only be 15" so an 18" planer should be fine..  Totally agree, having the grain align and  wrap around the  cabinet from   side to side  would be  tricky, and  even more so  whenn  you'd want  both cabinets to  be "book matched" to each other.

After creating  a  1.5" thick panel,for the baffle there  would also be some CNC issues I can think of and again  you'd have to keep  the grain pattern in mind throughout the process....... lots to  consider

My initial thoughts stand,   veneered MDF cabinets  would be far  more   cost effective.  I've seen some  great   veneering job both on the  wedgies from you  and the  NX Ottica MTM's from Ed 

jay

aceinc

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Re: New NX-Otica MTM section only
« Reply #47 on: 7 Feb 2017, 01:36 pm »
My thought on the solid wood, might just be the baffle and the small wing. Pieces that could be easily cut from a single piece of lumber. The other pieces veneered.

For example I am considering building the OB W frame sub. My thought is to use MDF for the construction, but since it is recommended to use double thickness on the sides, I was considering wrapping all four sides in either dimensional lumber or 3/4" veneered plywood.

aceinc

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Re: New NX-Otica MTM section only
« Reply #48 on: 7 Feb 2017, 03:05 pm »
One reason for using two different types of material on the the sub is that whey would resonate at different frequencies. My thought is that one would dampen the resonant frequency of the other.

drmike

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Re: New NX-Otica MTM section only
« Reply #49 on: 7 Feb 2017, 03:45 pm »
are the mtm flat packs still available? how much $?
thanks,
drmike

danvprod

Re: New NX-Otica MTM section only
« Reply #50 on: 7 Feb 2017, 07:35 pm »
I'd be curious to get a total bill of materials on these as well. If I'd built, I'd likely do a black DuraTex coating.

Danny Richie

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Re: New NX-Otica MTM section only
« Reply #51 on: 7 Feb 2017, 08:53 pm »
are the mtm flat packs still available? how much $?
thanks,
drmike

The NX-Otica MTM kit is $1,129 plus shipping, and that includes the flat pack. I forgot to add the tweeters when I quoted this earlier.

And the flat pack by its self is $239 plus shipping.
« Last Edit: 8 Feb 2017, 02:31 am by Danny Richie »

drmike

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Re: New NX-Otica MTM section only
« Reply #52 on: 7 Feb 2017, 09:48 pm »
tweeters are available for this kit?
thanks,
drmike

Danny Richie

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Re: New NX-Otica MTM section only
« Reply #53 on: 8 Feb 2017, 02:27 am »
tweeters are available for this kit?
thanks,
drmike

Yes, and the standard Neo 3 pdr can be used in this one.

AlmstRet

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Re: New NX-Otica MTM section only
« Reply #54 on: 12 Apr 2017, 07:47 pm »
Danny,

Looks like I'm ready to pull the trigger on my first GR Research project...and why not go big: NX-Otica MTM and H-Frame servo subs.

To obtain a full NX-Otica MTM kit (including flap packs), should I PM you?

Also, do you have any of the custom tweeters left?

Thanks for all your (and so many others) support in this forum.  I've had quite an education that will no doubt continue over the summer.

Once I get going on this I'll start a new build thread.

Thanks again. 
Bob

Danny Richie

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Re: New NX-Otica MTM section only
« Reply #55 on: 12 Apr 2017, 07:51 pm »
You can call to order anytime. 940-592-3400

And yes, I have the some of the custom tweeters still in stock.