Really closer to 5.25”.
Likely the closet is the Alpair 10.3. There has only been 1 fellow i have seen that has heard both… he preferred the Eikona. But between the A10.3 and the Eikona is the ENnABLed A10.3eN.
Both drivers came out of the same heritage, but diverged when Jordan got sold to EAD and Mark added his own touches to the Alpairs.
dave
Just my 2 cents. I have built the TL for the Eikonas (v2) and they are, in many ways, in a class of their own. I’ve tried a few Alpair models (although not the 10.3) and like them very much. But ted’s Eikona are just a cut above IMHO. They are a bit pricier and will need a few more watts, but the result is quite impressive indeed.
I sold them to a friend and he very gracefully changes subject if I ever ask if he would consider sending them back my way someday.
Oh well...
I sold them to a friend and he very gracefully changes subject if I ever ask if he would consider sending them back my way someday.
Oh well...
Well it sounds like they have quite a following of people who like them no doubt. If 5.25in then maybe something like the W5-2143’s that I have and like so much might be competition. The 2143’s are 90dB sensitivitive and are very neutral/flat response with incredible highs.
https://www.parts-express.com/pedocs/specs/264-958--w5-2143-spec-sheet.pdf
If anyone in the Metro DC area has a set, PM me if you wouldn’t mind letting me hear them.
https://www.parts-express.com/pedocs/specs/264-958--w5-2143-spec-sheet.pdf
If anyone in the Metro DC area has a set, PM me if you wouldn’t mind letting me hear them.
The originally design that I was looking at for 1 driver per cabinet was by Jim Griffin.
It was as follows:-
30 ins internal high with csa of 56 sq ins
Driver centered 6 ins from top, port centered 2 ins from bottom, both internal
Port 2 ins inside dia. x 6 ins. long
Stuffing 0.75 lbs cu ft down to 3 ins below the driver. ( Approx. 0.27 lbs per cabinet )
What I intend to do now is fit 2 drivers per cabinet as follows:-
30 ins internal high with csa of 112 sq ins
I will make it 11 ins wide internally x 10.18 ins deep giving 112 sq ins
Centre point of the 2 drivers 6 ins from top, port centered 2 ins from bottom, both internal
Ports 2 off 2 ins. inside dia. x 6 ins. long
Stuffing Approx. 0.54 lbs per cabinet
Is there anything wrong with my reasoning above.
I also have the following questions.
Should I offset the drivers to one side of the centre line
The top driver is right at the top of the cabinet to maintain thethe 6 inch centre point is that ok, I could always put an extra thick top panel on to get it away from the edge but by how much?
Finally stuffing I dont think I can get Acousta stuff in the UK ony BAF or Wool Felt to glue on the walls so what is the best thing to do here.
Thank you all for your help
It was as follows:-
30 ins internal high with csa of 56 sq ins
Driver centered 6 ins from top, port centered 2 ins from bottom, both internal
Port 2 ins inside dia. x 6 ins. long
Stuffing 0.75 lbs cu ft down to 3 ins below the driver. ( Approx. 0.27 lbs per cabinet )
What I intend to do now is fit 2 drivers per cabinet as follows:-
30 ins internal high with csa of 112 sq ins
I will make it 11 ins wide internally x 10.18 ins deep giving 112 sq ins
Centre point of the 2 drivers 6 ins from top, port centered 2 ins from bottom, both internal
Ports 2 off 2 ins. inside dia. x 6 ins. long
Stuffing Approx. 0.54 lbs per cabinet
Is there anything wrong with my reasoning above.
I also have the following questions.
Should I offset the drivers to one side of the centre line
The top driver is right at the top of the cabinet to maintain thethe 6 inch centre point is that ok, I could always put an extra thick top panel on to get it away from the edge but by how much?
Finally stuffing I dont think I can get Acousta stuff in the UK ony BAF or Wool Felt to glue on the walls so what is the best thing to do here.
Thank you all for your help
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OK, you didn't make it clear, i.e. this description initially or at least a link to JG's design.
Anyway, if stuffing, then you 'fluff' it out to fill the longer, larger tube. If using sheet insulation, then in reality it only needs to cover ~0.707x the panel area, so you can make the strips longer, but a bit narrower if need be.
GM
What GM said.
One practical point -I'm on an office computer & little time to check as I'm taking an evening seminar: is 6in sufficient physical clearance between the internal top & the centreline between the driver pair? IIRC the Eikona 2 basket is about 150mm wide so you're dancing right on the edge, especially as you'll likely need a small gap between the drivers to ensure sufficient structural rigidity.
One practical point -I'm on an office computer & little time to check as I'm taking an evening seminar: is 6in sufficient physical clearance between the internal top & the centreline between the driver pair? IIRC the Eikona 2 basket is about 150mm wide so you're dancing right on the edge, especially as you'll likely need a small gap between the drivers to ensure sufficient structural rigidity.
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Yeah, was surprised to see these specs too, so got me wondering if it was a modded plan of his original JX92S bookshelf speakers.
GM
Here is the original article
http://www.diyaudio.com/forums/full-range/265994-jordan-eikona-2-designs-print.html
http://www.diyaudio.com/forums/full-range/265994-jordan-eikona-2-designs-print.html
This specific link: http://www.diyaudio.com/forums/full-range/265994-jordan-eikona-2-designs.html#post4222009
OK, all is clear now, he chose to use the 1/5th harmonic for the driver location Vs the more popular 2/5ths or 1/3rd that most folks, including him, normally use, hence the need for much more damping due to the 'stronger' eigenmodes.
I totally missed the 30" height spec though and it should have been noted from the get-go since as Scott pointed out, this is going to put the top driver too close [~1.47"] to the top, which combined with heavy damping is going to 'muffle' it somewhat, so recommend either moving the driver's midpoint down to at least ~0.349*30 = ~10.47" or going to a taller cab if the drivers/floor height is already where you want it.
Offsetting is a good plan and use to recommend it a lot on wider baffles, but none bothered AFAIK, so gave up. I doubt it audibly matters though on narrow baffles where it's not much wider than it needs to be to mount 'FR' driver. With a 43 Hz Fs, 11" i.d. baffle, its eigenmodes comb filtering with the driver's output might be audible off the front, so recommend a golden or acoustic ratio offset: 1.00:0.618, 1.14, 1.17, 1.25, 1.26, 1.28, 1.39, 1.41, 1.47, 1.54, 1.60, 2.1 were the most common decades ago, so with '1.00' being the outer edge of the [mirror imaged] baffles, pick one that doesn't put the driver too close to the inner side wall.
Once you move away from polyfil, the only thing you can do is experiment with different materials, density till you find something that sounds good to you, i.e. it no longer sounds 'hollow' and maybe some more if the [mid]bass, or lower mids sound too resonant/whatever.
GM
OK, all is clear now, he chose to use the 1/5th harmonic for the driver location Vs the more popular 2/5ths or 1/3rd that most folks, including him, normally use, hence the need for much more damping due to the 'stronger' eigenmodes.
I totally missed the 30" height spec though and it should have been noted from the get-go since as Scott pointed out, this is going to put the top driver too close [~1.47"] to the top, which combined with heavy damping is going to 'muffle' it somewhat, so recommend either moving the driver's midpoint down to at least ~0.349*30 = ~10.47" or going to a taller cab if the drivers/floor height is already where you want it.
Offsetting is a good plan and use to recommend it a lot on wider baffles, but none bothered AFAIK, so gave up. I doubt it audibly matters though on narrow baffles where it's not much wider than it needs to be to mount 'FR' driver
Once you move away from polyfil, the only thing you can do is experiment with different materials, density till you find something that sounds good to you, i.e. it no longer sounds 'hollow' and maybe some more if the [mid]bass, or lower mids sound too resonant/whatever.
GM
Here are the plans of the ML30
http://www.ejjordan.co.uk/PDFs/Eikona_MLTL30.pdf
The ML38 or one of Jim's taller designs would be a better choice for a double MLTL
http://www.ejjordan.co.uk/PDFs/Eikona_2_38_MLTL.pdf
http://www.ejjordan.co.uk/PDFs/Eikona_MLTL30.pdf
The ML38 or one of Jim's taller designs would be a better choice for a double MLTL
http://www.ejjordan.co.uk/PDFs/Eikona_2_38_MLTL.pdf
I'm not GM, but FWIW the 0.349% offset is what Martin King specifies as the tap location for an untapered pipe in his alignment tables.
Golden ratio = 1:1.618 so for any lateral driver offset use said (providing there is sufficient clearance), i.e. lateral offet = external baffle width x 0.618. If that does not provide sufficient clearance, then use one of the other ratios GM mentioned. Ensure the cabinets are mirror imaged if you use a laterally offset driver.
Golden ratio = 1:1.618 so for any lateral driver offset use said (providing there is sufficient clearance), i.e. lateral offet = external baffle width x 0.618. If that does not provide sufficient clearance, then use one of the other ratios GM mentioned. Ensure the cabinets are mirror imaged if you use a laterally offset driver.
What would 1.14 offset mean when measured a cross the baffle width.
I assume we are talking about offset from the vertical centre line for both drivers.
Also should I use two ports or one.
I have also discovered that I can buy Acousta stuf Polyfill in the UK how much should I use in each cabinet.
One more thing does moving the drivers down affect the bass response, will I still get -3db @30hz.
The drivers are a bit low now but I can put a small base under to lift the speakers.
I assume we are talking about offset from the vertical centre line for both drivers.
Also should I use two ports or one.
I have also discovered that I can buy Acousta stuf Polyfill in the UK how much should I use in each cabinet.
One more thing does moving the drivers down affect the bass response, will I still get -3db @30hz.
The drivers are a bit low now but I can put a small base under to lift the speakers.
We've used BAF and it's been OK and easy to adjust. Don't get too hung up on the details at this stage as you can adjust later.
We have a customer use some very fine material called Angel Hair but the results in the MLTL40 weren't as good as BAF, imo.
Mundorf Twaron Angel Hair Wadding | Hifi Collective
Rather than add a base to the MLTL30, would it not be easier to build one of the taller designs and get added bass extension?
We have a customer use some very fine material called Angel Hair but the results in the MLTL40 weren't as good as BAF, imo.
Mundorf Twaron Angel Hair Wadding | Hifi Collective
Rather than add a base to the MLTL30, would it not be easier to build one of the taller designs and get added bass extension?
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Hi Colin
Thank you and all the other members for your help.
I Would rather stick to the 30 inch high design with a small base to bring the dual drivers up to required height.
Sorry but I am one of those people who like to have a clear idea of what they are doing before going ahead so the minor details are important even if they are just a starting point.
One of the reasons that I want to use the 30 in high cabinet instead of the taller cabinets is that I will be using a fairly wide baffle and will place the cabinets very close to the back wall, but about 6ft from corners.
This will obviously give quite a bit of room gain lower down and I am hoping that I will not need any baffle step correction.
Trying to finalise my design and this is what I am thinking of doing
Cabinet internal dimensions 30 ins. high x 112 sq. ins.csa.
Centre point of the 2 speakers 10.47 ins down from top internally.
Speaker frames 1 in. apart.
Offset drivers 50mm and make 2nd cabinet as a mirror image.
2 x Ports 2.0 ins. internal dia x 6 ins. long located 2ins. centre from internal bottom.
Is all the above ok to give performance of Jim Griffins design.
Final thing is damping / stuffing.
I could use 8mm wool felt as Scottmoose suggests the type sold by Jantzen Audio.
Will this be enough or should I just use Acousta Stuf Polyfill and if so how much per cabinet.
This will obviously give quite a bit of room gain lower down and I am hoping that I will not need any baffle step correction.
Trying to finalise my design and this is what I am thinking of doing
Cabinet internal dimensions 30 ins. high x 112 sq. ins.csa.
Centre point of the 2 speakers 10.47 ins down from top internally.
Speaker frames 1 in. apart.
Offset drivers 50mm and make 2nd cabinet as a mirror image.
2 x Ports 2.0 ins. internal dia x 6 ins. long located 2ins. centre from internal bottom.
Is all the above ok to give performance of Jim Griffins design.
Final thing is damping / stuffing.
I could use 8mm wool felt as Scottmoose suggests the type sold by Jantzen Audio.
Will this be enough or should I just use Acousta Stuf Polyfill and if so how much per cabinet.
Greets!
If it was a closed pipe, then it would be ~0.333, but the vent shifts it down a bit, so its odd harmonics wind up being ~0.21, 0.35, 0.42, 0.70, 0.85, though in most cases using the 0.2, etc., will work just as well since typical damping density will drop it to inaudibility.
GM
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