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Mjölnir Subwoofers - Page 2

post #31 of 121
Quote:
Originally Posted by kgveteran View Post

So, why not bolt the speaker to the hole where it ususally drops in. No question you can brace the box front to back, side to side, top to bottom...with no attention to the basket protruding to the inside of the cabinet.

So wiring it out of phase and firing out through the basket as its primary direction isnt a problem....

youd have to weigh down the other side of the box like crazy to keep it sitting flat. Just one point, at least for this particular build, smaller drivers, the bracing wont need to be as articulate anyways
post #32 of 121
Thread Starter 
Bracing has been quite the challenge. Mainly because of the physical size of the LMS drivers in consideration to the size of the box. Had the boxes been larger the bracing creativity could expand. These drivers extend and occupy a large amount of space inside of 4 cu ft. which makes "ribs", "torsion box", or "dowel rod" bracing very difficult because there is just no space for the wood to go down the very middle of the box. So you end up bracing the corners and outer panels, hence the challenge of bracing the middle, top to bottom.

I have spent many hours on sketchup trying to get bracing down the middle to properly implement bracing as it should be, but the basket and motor do not permit so inside a 22 in. cube. Notnyt has designed a brace that works well with these beast. I have tried to implement the advice of others, but again the drivers in this case dictate what is possible in such tight quarters.

On a side note a have gone further in the design to try and implement the faceplate which has been rather difficult. In short, the front baffle at this moment is 2.25 inches thick with about another 4 inches of worth of wood in front, for the faceplate. It is shaping up to be rather front heavy.
post #33 of 121
Quote:
Originally Posted by kgveteran View Post

So wiring it out of phase and firing out through the basket as its primary direction isnt a problem....

Not a functional problem, no, but as noted there are other complications
post #34 of 121
Sorry to derail your thread. Back to OP and bracing....
post #35 of 121
Thread Starter 
Would I need two speakon connectors per box to connect to an LG clone amp?
Which type of speakon should I be looking at
post #36 of 121
Newb alert... Sorry in advance if this is a dumb question.

I was wondering why you guys mount subs in shared airspace like that. If you separated the box the solid panel would act as a great brace while also isolating the subs from each other. I guess it's the pessimist in me thinking that if one sub wasn't manufactured to be exactly like the other they could create different pressures in the box and somewhat cancel the other speaker. In their own airspace that isn't an issue.

I understand why you'd share airspace in dual opposed setups, but if they're aligned it seems like it would be better to put a divider in there to me. Is this off-based?
post #37 of 121
Thread Starter 
Still looking for help regarding the jack plate.

Should I do binding post or speakon connectors?

Will be using LG clone amp.
post #38 of 121
Quote:
Originally Posted by ovrrdrive View Post

Newb alert... Sorry in advance if this is a dumb question.

I was wondering why you guys mount subs in shared airspace like that. If you separated the box the solid panel would act as a great brace while also isolating the subs from each other. I guess it's the pessimist in me thinking that if one sub wasn't manufactured to be exactly like the other they could create different pressures in the box and somewhat cancel the other speaker. In their own airspace that isn't an issue.

I understand why you'd share airspace in dual opposed setups, but if they're aligned it seems like it would be better to put a divider in there to me. Is this off-based?

not at all really, Im surprised at the builds that do this as well. Another benefit is if one driver malfunctions or blows, at least the other one wont be affected.

Quote:
Originally Posted by bodhisafa View Post

Still looking for help regarding the jack plate.

Should I do binding post or speakon connectors?

Will be using LG clone amp.

I always go with binding posts for simplicity, and the fact that im not that familiar with speakon cables, but i get all my regular 12 or 10 gauge on the cheap so I just use the ole tried and true.
post #39 of 121
Thread Starter 
My 10,000 dollar CNC setup




Wood is cut ready to go for this weekend minus the whole cutouts.





I tested the whole cutout on a scrap piece of wood using a 1/4 diameter upspiral bit and ended with a diameter of 17 2/16. The whole seems too big for all the screws too attach too. EXACTLY HOW BIG SHOULD THE WHOLE BE?

The TC Sounds schematics say whole to whole 17.40 inches, and basket to basket 16.83inches.
post #40 of 121
I thought I had cut mine 16.75 but I could be wrong.
post #41 of 121
Thread Starter 
Update: Box number one done.



post #42 of 121
Thread Starter 
I have a question about the wiring. Local store has THHN stranded wire from 1 strand all the way up too 14 strand electrical wire. 10, 8, 12 gauge. Are any of them good to use when wiring the driver in series to the speakon connector?
post #43 of 121
I cut the hole about 17". If you need larger, you can route a lip around the edge so the basket can fit

Why did you make that overhang on the front? That may affect sound quality.
post #44 of 121
I wouldn't recommend using house wiring stuff for this. Order some 10 or 12 gauge speaker wire.
post #45 of 121
Thread Starter 
Quote:
Originally Posted by notnyt View Post

Why did you make that overhang on the front? That may affect sound quality.

For the faceplate idea I have involving plexiglass.

Will it affect sound quality???? Not sure about this.
post #46 of 121
Thread Starter 
Iam in the finishing stages of this project and was wondering about the wood grain showing through the paint. Would I need to bondo all wood surfaces before paint or is there primer that will hide the grain.
post #47 of 121
just use duratex. It is a textured black paint that will cover any and all grain that you have and it is superstrong
post #48 of 121
Thread Starter 
Thanks for the suggestion beast, but I was hoping for a little nicer finish. I am wanting something in a matte finish.
post #49 of 121
Thread Starter 
Quick update were I am in this project. The plexiglass/LED idea was tossed to the side as plexi happens to be rather expensive at certain thicknesses. Other than that the boxes and the face plates are ready for bondo and resin....and lots...and lots...of finish work.




post #50 of 121
Wow!
post #51 of 121
Those look awesome!
post #52 of 121
Thread Starter 
Its been a while project is almost complete.

I have in route two Itech 8000s to power both cabs of a 240 volt line but need to do some free air testing to make sure the LMS drivers are not defective. how do I go about doing this exactly.

Also the Itech have a lot of menu options (limiters, input, output, sensitivity, voltage limiters, clip limiters attenuators) were should all this be set too in order for proper operation ??????
Edited by bodhisafa - 11/10/12 at 6:18am
post #53 of 121
Quote:
Originally Posted by bodhisafa View Post

Its been a while project is almost complete.
I have in route two Itech 8000s to power both cabs of a 240 volt line but need to do some free air testing to make sure the LMS drivers are not defective. how do I go about doing this exactly.
Also the Itech have a lot of menu options (limiters, input, output, sensitivity, voltage limiters, clip limiters attenuators) were should all this be set too in order for proper operation ??????

IT8K_LMS18.I-Tech Series.zip 16k .zip file

I've attach my iTech 8000 device file that is suitable for a pair of TC LMS's.
I spent hundreds of hours fine-tuning these settings to get maximum performance out of this amp/sub combo.
Needless to say, I have great success with these settings.

This was made with SystemArchitect version 3.1
All you have to do is unzip it and open it with that, and upload it into your amp, and set it to preset #3 LMS-18.
Should work.

I run mine on a 240v/15amp line.

It is optimized for two sealed TC LMS-U 18's @ dual 1-ohm; I've been running it like this for 9 months without any problem, it rarely exceeds -10db output power before the LMS hits it's limits.
You should probably do some light refinement to these values to match closer to your room/sub, just MAKE SURE you turn down the volume because I have it set VERY HIGH (-20db).

There is almost nothing I don't know about these amps if you are looking for an expert opinion.

Here are the settings I have applied to it:

553
411
399

Monitor your amps in/out console to make sure you don't see any red clip lights during loud music.
254
post #54 of 121
Thread Starter 
^^
Thanks Bass, that should help. Would it matter that mine will be wired for a 4 ohm load per channel.

However I dont have access to that program and getting my computer setup upstairs maybe a problem???
Edited by bodhisafa - 11/10/12 at 5:44pm
post #55 of 121
Just visit their website, it's a free download.
Using their app is NOT optional, it's required... at least for the initial setup.

Otherwise you'd be using the factory default or worse, someone else's settings... which is a very bad idea.

Just take the amp downstairs, it has a universal power supply (any voltage basically), it only draws ~200watts when not powering speakers. (Or a network router with two 150ft cat-5 cables.)

Any ohms between 1-8 is fine, the amp has thermal indicators as long as it doesn't go above 50%, then you'll be fine. Which is visible on the front display. (It also has a clip counter, that should always read 0-0.)
From my experience with it, you'll get more excursion with 1-ohm, but 4-ohms it technically the "safer" option.
post #56 of 121
Pretty slick build ! Great attention to details. With those drivers in those cabs, bass shoulnt be a problem !
post #57 of 121
Thread Starter 
Quote:
Originally Posted by kgveteran View Post

Pretty slick build ! Great attention to details. With those drivers in those cabs, bass shoulnt be a problem !

Thanks! This my first build ever, it's been quite an experience.

BassHz I meant to ask you if you have two I techs running on one 240 line. My electrician friend that's about to wire the setup has never heard of two appliances being connected to one 240 line.

I'm using a 2 pole 30 amp breaker hook to this receptacle http://www.platt.com/platt-electric-supply/Receptacles-Commercial-20-Amp-Duplex/Leviton/5822-I/product.aspx?zpid=35223

Would there be any problems??
post #58 of 121
Generally 240v is a single outlet. I was thinking about doing the same but my electrician friend just ran another run of wire. If possible, I'd not run 2 on 1 outlet.
post #59 of 121
I would recommend that he uses 30amp wiring and installs two of those receptacles, wired in parallel, with the breaker-bar snapped off so that only 2 of the 4 sockets are active; otherwise if you use only one you could exceed the receptacles rating (20amps).

That might be just enough power to dim every light in your house each time the bass thumps wink.gif
post #60 of 121
Thread Starter 
Ok now you guys have me worried.

I contacted Crown and the gentlemen suggested (2) itechs per 240 on a 20 amp breaker line would be fine.....but did not say how the electrician would wire the setup.

Another member on this forum, who is well respected, suggested the same but with a bigger breaker.

Here is the current draw per Crown: http://www.crownaudio.com/media/pdf/amps/137435.pdf

Based on the numbers I should be fine running two on one line, but my electrician is worried of possible overload.
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