Design a Bose-beater

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The Aura has 5mm+- xmax,
The Hi-Vi is 3mm+-

I think the extra x-max is very important in this case if it allows us to go down to 100hz

Also, I can't tell if either one or both use neo magnets. since we are fighting for space, an extra cubic inch or so due to neo might be well worth it.

This will really help:
You can integrate the stand into the cabinet to pick up some extra volume and still keep the cabinet really small.

A good trick that the Bose guys don't use. Even a 2" dia column would help a lot. And if it is stuffed, I don't think the shape would matter too much, right?

Tiny cubes on elegant slim tubes, -cute indeed, and what an advantage: she can move them around, they don't take up shelf space, they look scuptural.

And we know:
-we get more cabinet volume (1/2" MDF or hardwood would work fine for the cube)
-The speakers won't be put on a shelf where they will sound pretty bad no matter what!

The bases could be wood or metal plates OR : 1" high metal boxes with the amps built in. I guess this would require a power cord- not at all cute - never mind.... WAIT- I've got it! the bases are say 10" cube subwoofer boxes. The sub driver weight balances them, and the box on the floor isn't that noticible, and gets floor loading. If her floor isn't carpeted, the woofer could face down. This would allow crossover at 150hz 'cause the sub is right with the head. If her floor is wood, then the cubes should match it.

Boy! if you could mock these up with say a 5" solid hardwood cube for the "head" with a great finish, a 3' length of 2 1/2" dia. aluminum with a brushed finish, (or painted black if she thinks it's too flashy) (or you could use a 2 1/2" cardboard tube and cover it and spray black) BUT everything would have to have a really nice finish.

and a 10" per side cube on the bottom, and she signed off on it, I think that this could become a classic!

Conservative Column Volume: lessee.... say the internal diameter is 2" in case you decide to go with 2.25" diameter tube with 1/8" walls. Radius 1, 1 squared times 3.14 = about 3 cubic inches per inch of column. a 36" column would have an internal volume of
108 cu inches- about the same as an additional cabinet of about 5x5x8" exterior size. Or: the total cabinet volume would be about
172 cu in. or 2.8 liter or .1 cu ft. hmmmmm, how about it guys?
will the Hi Vi B3N work? With aperiodic loading? Can we do a linkwitz transform to extend the bass so it works in 2.8 l. ?

I guess the crossover point is determined by whether she goes for the sub as a base or not. If she goes for the sub base then the Hivi would work at 150 hz maybe, and the round frame varient is very cute and attractive. If she doesn't like the sub-in-the-base, then the Aura crossed at 100 is prob the way to go.....

... Kelticwiz: seems like your scheme would be fine with this
Maybe the extra volume would allow a 100hz crossover if the sub had to be remote?


These could be great HT speakers for many of us!
 
It could also be that Mark responds to the posting of DJMiddelkoop, without looking on the website, only the speakers, and because looking only for 5 seconds, he doesn't know that those are ESL's.

Yes indeed, Joris has seen it right, it is noot a cheap Walmart or Kmart system, it is an active sub with 3 ESL's.

The 3rd ESL can be used as center in a surround system.

The ESL measures 10 by 30 cm which is approx 4 by 12 inch.

Dick
 
Re: Jordan JX53

Peter M. said:
What about Jordan JX53 fullrange? It could be used in a box as small as 0,34 litres. The Jordan website states a frequency range from 100hz to 30khz.
And it is supposed to sound really well, sensitivity is 87,26 db.


Regards,
Peter


I doubt whether a small 0.34 liter box will giv eyou much bass with a driver that size down to 100 Hz. You can use the JX92S in a larger box and get real sub 100 Hz coverage.

On that JX53 sensitivity: That 87 dB is before baffle step compensation. Figure 3-6 dB less sensitivity for BSC with the JX53 in a typical box spaced away from the walls.
 
Or are you saying that Wal-Mart sells, at $34.95, a better home theater system than Bose-but not one that necesssarily contains the same drivers as the Aura NS-3 or the HiVi B3S?

Yea, I think the Bose system is a piece of junk of which an equivelent Chineese copy can easily be bought for 34.95 at wal-Mart. Its certainly ALOT better than the tiny speakers in my Samsung LCD TV and a better value than the equivelent size Bose product.

Mark
 
Here's my take on the inexpensive Bose beater. Three inch full range and four inch woofer. Four inch doubles the lower range only to reinforce the bass output from 200 Hz down. The integral stand uprights are used as speaker air volume and stuffed to kill standing waves. 1/2 inch MDF. Only slightly larger than BOSE. 5.5 inches wide by 6.5 deep by 8 high. 3.5 by 5 at top of cabinet. Inner cross partition to seperate four inch from modulating low x-max of three inch full range. Aperiodic loading of upper driver. Lower stands have hidden vent in rear for aperiodic loading of woofer.

Hezz
 

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Also another idea,

If you are forced to use 1/4 inch MDF for the cabinet. Layer the inside and out with one layer of fiberglass cloth and epoxy resin. If a thin brace is used inside this will make the cabinet a lot more ridgid without adding much size or decreasing internal volume.

Hezz
 
Re: Jordan JX53

Peter M. said:
What about Jordan JX53 fullrange? It could be used in a box as small as 0,34 litres. The Jordan website states a frequency range from 100hz to 30khz.
And it is supposed to sound really well, sensitivity is 87,26 db.


Regards,
Peter

Might just work. It is just a tiny bit wider than we want, but just about everything is. Everyone please remember, the object of the exercise is to make a system with satellites that are as small as the B-se AM-15. Making a system that just sounds better for the same money (or 1/8th the money) is trivial.

Here is a simulated FR plot of the JX53 in a 57 cu in sealed box. The Qtc is about .95. It looks like you would need to cross it over at 140Hz or more, but, hey, that beats Bo$e!
 

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What about this:

You could put the jordan JX92S in a 5" cube made of 5mm aluminium, and use an aluminium tube like Variac suggested to increase the internal volume.
Or if you want it to be even smaller, the JX53 in a 3.5"X4.5"X3.5" box.

Hmmm... aluminium cone, aluminium box, aluminium tube, i think that would be cool😎

Regards,
Peter
 
Been lurking for a few months and I'm really getting sucked into this thread. I'm pretty much in the same boat as Dave, 'cept I'm married and therefore have a bit more pressure on me for the asthetics. 😉

I found a Phillips 5:1 for $47 on ebay and it works ok for HT apps, it's really weak for music though -- it's missing all of the low mids and highs and another speaker solution is a definite must. So, I'll be watching things thing with a lot of interest. That's all, just wanted to officially pop my head in and say hi!
 
I think that the scheme that I synopsized from various peoples ideas including my own is a fair varient on the Bose theme.

the satallite units are tiny and you DO need a stand for them usually, and even thought Bose makes it black, the subwoofer DOES exist and needs to be dealt with. So, here is a fuzzy diagram of how it might look. The cube could be 1/2" MDF and still be OK due to the tube voulume, and an MDF cube is a lot easier to make! The tube could be black if it needs to be less obtrusive.

It also looks a bit like a giraffe, and what's cuter than that?
 

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Hi Dave

Reading through the thread, I was going to suggest the JX53s before someone else made the connection. An aluminium enclosure would be a good way to maximise the internal volume. For added inspiration, take a look at

www.beoworld.co.uk

go to the alphabetical list and look at the Beovox C30/40 or 75. Not as small as Bose but they score high in the Significant Other Approval stakes.

Colin
 
Re: Re: Jordan JX53

Me Myself said:

[JS53 ] Might just work. It is just a tiny bit wider than we want ...

Duh. El Stupido here looked at the picture on the Jordan web site and failed to snap that the thing could be mounted with the long dimension vertical. The shorter dimension is only 75mm (a bit under 3 inches), and I think it could be mounted in a box that's only that wide.
 
How about the crossover? Using one of the itty bitty speakers (whichever), the xover will be in the 125 to 180Hz range, one would imagine. If the little speaker (JX53 maybe) has no high pass filter on it, will it beat its poor little self to death trying to play notes below its tuning frequency? Will it produce a lot if IM distortion with no high pass filter?

Ideally, the system would work with an integrated amp/preamp for the mains and a plate amp for the sub.
The only integrated amps I know of that have pre-out and main-in are NAD's. Is it feasible to use just any old integrated amp, or will an active high pass be necessary?
 
Jordan seems to recommend from .34 l. to 1.0 l. for their 52 drivers.

I can't see that they would work well below 150 hz.
Seems like the subs would be required to be close to the mid /tweet drivers or you are duplicating the Bose prroblem with no low mids. It seems from what I've read recently, most people have decided that its best to cut off a fullrange driver where it crosses to the woofer , rather than let it try to reproduce the low notes. Better to have the high pass filter components on the mid/tweets than all the problems that you mentioned due to them trying to reproduce bass.

Speaking of which, I picked the size of my bass box at 8" square arbitrarily. Maybe it could use a smaller sub driver made for the purpose. I think we need some input (as you requested ) from people as to whether there is a tough little 6", high x-max bass driver that we could put in a small box and equalize. Maybe the box could be 8"x8"x 5" tall. That would look a lot svelter than the drawing I posted! Even if it only went to 70 hz, that would sound pretty good...
 
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