I just saw he now lists a Be dome option for the 71’s, have you considered that? Might allow you to have a lower value as the response should be cleaner.
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Own designs += @chris5
(Apparently there’s a limit to the amount of users that can be mentioned in a single post)
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Hi n-lot, yes I saw that, however I feel I have a nice balance now and have removed my test setup. When I do my next build I’ll definitely build that in.
Sorry for the slow reply.
Cheers
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I just weighed them today. 57.8 & 58.5 kg.
So a 0.7kg (1,2%) difference between them, not yet sure where that would come from. First thoughts:
- bracing was partly cut using a router, so there could be a small difference in hole diameter.
- tolerances in electric components/drivers
- I realised afterwards I didn’t disconnect speaker wires (stupid), but doubt that will account for more than 0.1 kg.
What’s the dimensional difference between them? Are they within a mm of each other on each dimension?
Did a quick calculation of two cabinets, using the dimensions of the 3WC 15, but made one a mm taller and a mm deeper, using 20 mm Baltic birch, and 680kg/m^3 I found 27.85kg vs 27.92kg (I ignored the bracing entirely) so less than 100g.
It’s an interesting difference but hope you’re not worrying about it!?
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The outer dimensions are identical to a fraction of a mm.
By my calculation, if I had cut all bracing holes 5mm bigger on one, the difference would amount to 0,36kg, so about half the difference. But while I’m sure there will be some difference here or there, it will more likely be a couple of mm max, and unlikely to be in the same direction everywhere.
It could of course be a combination of factors. If I feel like it I might take out the crossovers and weigh those. I probably won’t bother with the drivers, it’s more curiosity than worry and that wouldn’t be worth the hassle.
I was thinking that as well - it’s almost like something is missing, or extra, than a tolerance thing. I’d assume (which is always dangerous!) that tolerances for this sort of thing would generally balance out.
They’re only about 15kg less than I weigh - can understand why you don’t want to weigh again minus cables!
I might just do that. I still have the masking tape marking their position in place. It’s just a fiddly job.
I can lift them using mounting cushions and then slide two bathroom scales underneath. But then there’s the fiddly bit of turning the scales I have on (press down on them with considerable force), wait till they zero, quickly deflate the cushions, retract them, and read the scale before they automatically shut down again.
Getting that timing right took a few attempts.
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This morning my daughter stepped/jumped on the bi-wire jumpers. Turns out bananas aren’t designed to hold a small child :-/
As I was having to disconnect them to perform emergency surgery on them I decided I might as well give the weighing another shot. Without any connected cables this time. I also enlisted help to make the process a bit less fiddly with each person only having to keep an eye on one mounting cushion, scale & side. And I also put something under the lower profile of the two scales to make them similar in height.
And the results are hopeful. The process is easier, and the weights are much more in line with each other. I suspect the tilt of the scales because of their height discrepancy might have thrown the previous measurements.
I’ve now weighed them to be 57,9 & 58,0 kg respectively, a 0,17% difference.
I also weighed the crossovers (inc. removable panel & still wired to the drivers) but this proved tricky. It looks like the scales aren’t very precise at these kinds of low weight as I struggled to get consistent measurements. By retrying a few times and cross referencing with both scales I put them at 4.4kg each, 7,6% of the total weight!
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Hi @n-lot + @Mark63
Hope everyone is ok and enjoying their speakers. I am. I have recently upgraded the tweeter on my Fusion for the Beryllium version. Improved detail in the top end. Not world changing but a very good improvement all in all. And still nice and smooth.
@Mark63 any thought of building a bigger speaker yet?
@gthack have you started your build yet?
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Kinda X)
Only managed to sort a couple of benches out, and 5 panels of a test cabinet so far. Then due to the test cabinet being less square than I wanted, I made a bathroom cabinet to practice with the tracksaw. And that’s as far as I am. Here’s the benches, one’s a MFT, I bought the top, made the sides with the T-track. The other bench is just a top and sides, to make cutting full MDF sheets up easier. Both just sat on an old workmate and a couple of saw horses.
At least the bathroom cabinet was good enough to put in our bathroom, rather than the skip 
Test cabinet just held with a strap
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Hi Mark, good to hear from you, and great to hear you’re still enjoying your speakers and that the new tweeter is working out well!
Do you still have your CNO’s?
I’m still loving mine and a while ago I did consider the beryllium tweeter option too, but the cost put me off a bit … thought it better to put that money towards a new build. However I’m tempted to try the new ScanSpeak TCPD carbon tweeter, according to Troels it’s as good as the beryllium dome but cheaper.
As for a new build, yes that’s very much on the cards still, just have some health issues to get over first. I was pretty much set on just building the floor stander version of my speakers, so much so that I bought a pair of ex demo Kudos Super 20a’s as stand ins while I built the new cabinets!
Plans have changed though and I got a quote for the Ekta-7741’s a couple of weeks ago 
Cheers,
Mark
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Hi, benches look great! Yes it can be tricky to get the cabinets truly square with hand tools. I think I posted this pic in my topic … I found that cutting the top and bottom of the side panels together from one sheet and then cutting lengthwise worked well. Same for the top and bottom of the cabinets. This makes sure they’re identical lengths, just remember to allow for the blade width!
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Plenty of woodworking shops will have a format/sliding panel saw. It might be worth inquiring if they’d let you use it, or perhaps have them do a few cuts for you. Some schools, like trade- or artschools have them as well.
And then just do all the braces routing and everything else at home.
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Yes I still have the CNO4’s, i couldn’t bring myself to sell them. I will rebuild them over the course of this year with a few small modifications. I have cut off the bottom chamber where the bass unit sits so that it is flush with the bottom. I will buy some iso-acoustic Gaia’s as feet. They are tall enough to allow the bass to disperse. I will move the port to the front to make room for the hypex on the back. I will also upgrade to the hypex 501 plate amp. After living with the Fusion (passive) for a few years I do miss the impact and adjustability of the active bass section.
Interestring upgrade plans for you! How do the kudos compare to the illuminator bookshelf you built?
I had considered building the 7741 at one point. Also the revelator 851. Don’t underestimate the revelator drivers they are really nice. Supposedly not much between them and illuminator apart from dynamic headroom when played loud.
Sorry to hear you are having some health issues. I hope nothing too worrisome. I Also have some health issues at the moment. I was recently hit by a car whilst riding my bike. 6 fractured ribs and a broken scapular that required surgery, which is not a pleasant experience. My left arm is pretty useless right now and most likely will be for the next three months or so. so my speakers have to wait. 39kg just for the empty cabs!
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@gthack you have to stop procrastinating on this speaker build.. it looks like you have the skills and all the equipment.. they don’t have to be absolutely perfect.. I say just go for it.
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there’s definitely a bit of procrastination involved! Things are also really busy, though if I spent the time I do on the forum on the speaker build instead, they’d soon be done. Both my partner and I work full time, two kids, I look after the house during the week, and spend a lot of time in evenings and weekends with the youngsters taking them to their sporting commitments. They’re swimmers and train 6 days a week, plus competitions. I also train, running and swimming. Spare time is late evenings and the odd weekend morning. The speaker build is a real luxury for me, it’s trite but true that the journey needs to be, and has definitely been so far, enjoyable! 
I’ve also had other system changes, which took money. My amps are now a fully serviced set of CB 42.5/HiCap/110, and I only just sold my NAIT XS3, the proceeds from which should go most of the way to the Illuminator 71 kit.
But I fully admit, there’s definitely procrastination involved
I used to cycle a lot as well, only had the occasional bump, nothing requiring hospital. Well, one motorcycle accident needed a few stitches, but considering the miles I used to cover on two wheels, on and off road, I’ve been very lucky indeed. I hope you heal fully and quickly Mark!!
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