Jordan JXR6 driver array with SEAS bass unit.

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This will be my first foray (yikes) into multi driver based speakers. I have built single driver (full range) speakers in the past to great satisfaction.
I recently completed a TL speaker employing Jordan JX92 for the drivers. I always suspected I would like the sound of Jordan drivers and this past project confirmed everything that I had thought. The speakers are accurate, non fatiguing with an exceptional soundstage. I have read on this forum and on the Jordan website very positive responses in regards to set ups that use multiple (preferably 4) drivers in a vertical array. In every case the 2” Jordan drivers need to be matched with a suitable bass extension unit. The single Jordan drivers if inserted in a 1.8 litre enclosure provide for an Fb of 120Hz. So I need a driver to pick up the rest.
Since this being my first multi drive project I have no experience with cross overs or for that matter complex enclosures. I have attached a rough sketch of the proposed speaker. The physical dimensions are about 4.5” wide x 12” deep x 4’ high. These sizes are based purely on esthetics and some information from the Jordan site about box dimensions for linear arrays. I like the idea of a very narrow face and a side firing bass unit. But beyond that they are based on NO actual measurements or calculations
I imagine that this project will take a while, I am in no rush and look forward to experimenting and learning as I go. It would be great if people would point me in the right direction, help me ask the questions I need to be asking at this point and any suggestions that they might have in regards to driver matching (I was thinking SEAS), enclosure dimensions, crossovers and vents. And how I might go about analyzing this data and doing calculations before I cut my first piece of wood.
Thanks for this forums continued support and I look forward to moving a head with this project.
Cheers
 

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My current home speakers are shaping up to be very similar to your picture, I have decided to go with the Bandor 50s instead of jordans (VERY similar drivers), just a pair of drivers per cabinet as I don't feel I need the extra sensitivity of 4 units each side. I tried the Seas 8" aluminium coned bass driver and to be honest I was quite dissapointed in its response (it seemed to ring on transients, drum hits and similar sounds which start and stop very quickly), I then found a pair of Bandor 150s in a rather sorry state and had them re-coned, these (currently in test cabinets) are giving me a slightly more precise sound, they seem to handle transients much better than the seas (they also show up my poor unbraced box much more :( ).

EDIT: I also heard a pair of Visaton 5" aluminium coned units at the weekend, they seemed very good for the money, maybe they do a suitable 8"
 
Yep all Bandors are still in production, 150s are a suitable 8" driver and the 100s would be good if you need someting smaller (lots of different VC options too). I managed to bag a pair of damaged ones cheap and buying them and the recones worked out at considerably less than new drivers. Mine are all done with Gunmetal anodized cones (blue/grey metal) with black anodized chassis. they should look really nice against a light wood cabinet.
 
Puggie,
I would be very interested in hearing about your design process, box dimensions and cross over network. As i mentioned this is my first foray into multi driver speakers and i am hungry for any prompts or information.
How would you compare the sound of the jordans to the bandor 50's?
I had a look at the bandor site and i like the idea of using drivers made by the same company... greater chance of synergy and matching.
 
The Jordans and Bandors are basically an evolution of the same driver, Doreen Bance (Ban Dor) and Ted Jordan used to be married, they worked together for goodmans pioneering the use of aluminium for loudspeaker cones in the 60s. Between them they got it 'right' IMHO then when they devorced they got Joint interlectual property rights on their developments so went their seperate ways on the development and production of the driver. The Bandor 50 and Jordan JX6 are both 50mm drivers using aluminium cones and high compliance suspension. I went with Bandor because they are based about 35miles down the road from me so I can Phone Doreen have them made with the colour cones I want in the choice of voice coil I want and then collect them a day or so later, if there are any problems I can go see her about them (there havn't been).

A friend of mine has the JX6s and I find the Bandors slightly smoother at the top, it is a very subtle thing, If I already had the jordans I wouldn't change.

I went with the seas looking to keep with aluminium cones for the same reasons as you to help the drivers blend well and keep tonality as consistent as possible. I think the Jordans are just a more similar driver, the have a very thin delicate conethat is damped and doesn't ring like the Seas which is much heavier and more rigid.

My design process has been sort the 50s to give me as much as I can, they play nicely down to 150Hz in 1.5l per driver, I have been told non square boxes are better so I'll be doing a translaminated box from MDF next with the layers cut randomly inside to give lots of rought surface for internal difraction of the sound, I found a long tapered enclosure worked well for one driver reducing the inrenal reflection. I also played with MAPD style loading, two chambers with an aperiodic membrane between them, I may go further into ths as it seemed promising reducing the excursion very well and I believe it should have flattened the impedence variations also which would make my Xover nicer to design, not having to deal with the impedance hump about Fs.

Once I have the 50s working as I want, I'll set too on the bass drivers, I want to fire them out as you have in the base of the cabinets (I'll probably make the 50s and 150 cabinets seperate and sit one on the other). My current thought is to go sealed to keep the size down and use a linkwitz transform to dig the real lows out of them, they have a LOT of excursion capability so shall be fine with the artifically increased bass.

I'm hopingb to cross the two cabinets over about 150Hz at 12dB/oct. I would like to expand this setup to a 5.1 home cinema affair and use another pair of '50' drivers for the centre and possible single 50s for rears. In this instance I'll run the 150 cabinets from the sub output of my home theatre amp whic has the ability to lum all the bass together and sent it to the sub channel for those who are using small main speakers. the crossover point for this can be 60/90/120Hz so I'll then be crossing over at 120Hz which I think should be fine.
 
soongsc said:
Hmm. with the manufacturing experience that Doreen has, it could be possible that a better damped cone was developed.


Well I know I bought a pair of 8Ohm drivers 12 months ago and 2 pairs of 4Ohm drivers a couple of weeks back and the 4Ohm drivers do sound a little sweeter, the 150 recones had damping painted on the backs of the cones the same as the 50s which the original 150s (13yrs old) never had. She keeps talking about going over to Neo magnets for the 50s, I know Doreen is doing a pretty constant evolution of the products.
 
Puggie said:



Well I know I bought a pair of 8Ohm drivers 12 months ago and 2 pairs of 4Ohm drivers a couple of weeks back and the 4Ohm drivers do sound a little sweeter, the 150 recones had damping painted on the backs of the cones the same as the 50s which the original 150s (13yrs old) never had. She keeps talking about going over to Neo magnets for the 50s, I know Doreen is doing a pretty constant evolution of the products.

Where did you get them reconed? I have a pair of JX125 one of which the surround is starting to crack.

You mentioned the 50s, are these the Bandor or the Jordan?

If you happen to find a pair of JX62 please let me know.
 
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