Speaker Build - CNO Grande

Glueing the inner front panel …

… and the outer front panel. This took up quite some time as I don’t have enough clamps to do both speakers at the same time, and I like to leave them clamped for at least 6 hours.

First cabinet!

Last part of the cabinet assembly is to make the detachable bottom panel. First I need to figure out where the binding posts will go. The horizontal lines are where the fillets for the bottom panel will be. Not much room between them and the port.

Ended up with them here …

… which means I’ll need cutouts in the fillet for the binding post nuts and connector.

Glueing the first fillet on the front …

… followed by the rest!

All the fillets in place. The cutouts for the binding posts were drilled with a forstner bit, large enough to get a socket on.

The bottom panel attached with recessed screws. A little room left for a foam sealing strip.

Mark

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What cost more, the drivers and crossover components, the cabinet materials, or the world’s supply of clamps!? :wink:

Can I ask how far from the rear wall you have them please?

Excellent build Mark. Great to see. Thanks for posting. For someone who has not done much woodwork, you are doing an awesome job. You are certainly a quick learner and have lots of patience.

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Hi @gthack, can never have too many clamps :slightly_smiling_face: I really must get some better quality ones though, these Silverline ones aren’t great, bought six and two of them can come loose :rage:

Just measured them and they’re about 70 cm to the drivers. I pretty much plonked them down where the old speakers were, want to let them run in before I tackle setting their position. They’ll probably come out a bit further … if I move them a cm a day perhaps my wife won’t notice :wink:

Cheers,
Mark

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Hi @Mark84, thank you :slightly_smiling_face:

I only have patience for things I enjoy! Been out in the workshop all day and it’s just flown by :grinning:

Cheers,
Mark

PS major screw up in the next instalment :grinning:

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Sanding down the cabinets. Cardboard in the driver and port holes used to prevent dust getting into the cabinets and damping materials.

I found that using a light close to the surface helped me spot things I’d missed, here one of the pencil lines is still visible.

One of the mitre joints had some small gaps, others are fine so not sure what happened there.

I made a filler from Valchromat dust mixed with PVA glue, since the glue dries clear it blends well.
That was the theory at least when I tried this much earlier on an off cut as it was something I wasn’t sure how to do. With a painted surface it’s just a case of using wood filler, and veneer would hide it, but with the panel material being visible in the final vinish it wasn’t obvious how to deal with this. I remember seeing this technique used when finishing the joints in wood floors so it seemed like it should work for this too.

The finished edge, rear corner needed a bit more work, must have knocked it at some point.

This shot from the finished cabinet shows the end result. Camera highlights the flecks in the Valchromat, they’re more subtle “in the flesh”

The cabinets almost ready for the hard wax oil, cleaned with a microfibre cloth first.

Disaster! :scream: I completely screwed up applying the second coat, the first went on really well, but for some reason I used a different method for the second and left it far too long before wiping off the excess. I don’t know what I was thinking :confused:
So this is the start of sanding it all off before starting again, took most of the day.

Second attempt, looks pretty good under the harsh LED lighting in the workshop. Not completely satisfied, one side has a slightly uneven finish and close inspection shows some areas I missed in the sanding stage. More time needs to be spent on that next time.
With this finish it’s possible to do invisible spot repairs, at least that’s what I’ve read, not tried it yet. So I may test that on some off cuts and revisit these areas.

Next job is the crossovers, I’ve never done any kind of electronics so was quite apprehensive …

Mark

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As I’m coincidentally planning to use the exact same finish, I’m curious if you can share a bit more about what methods worked and/or didn’t.

I was advised to just rub it in with a cloth, not leaving any excess. On a (small) trial piece this seemed to work fine.

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Hi, yes I completely skipped over that didn’t I :roll_eyes:

I’ve used this hard wax oil in the past on some wood doors, it gives a great finish and is very hard wearing … often used on floors.

For the first coat on these I used a brush to put on a thin layer then wiped with a lint free cloth. I did each panel in turn, wiping off before going to the next one.
Where I went wrong with the second coat was doing the brush part all over both cabinets before going back to the first to wipe them off. Of course by this time it had started to set. Like I said above, I really don’t know what I was thinking :confused:

For the second run a did apply each coat with a cloth, loading the cloth with a brush and then applying in circular motions, a panel at a time, much easier.

I’m pretty sure the areas that aren’t so great are due to the sanding, especially from the removal of the first attempt. Preparation is key!

Cheers,
Mark

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So onto what I was expecting to be tricky, for me at least … completely new territory.

But first the binding posts, the rather large port and the sealing foam strip were added. I will clean up the bottom :slightly_smiling_face:

Starting the crossovers, constantly referring to the photos and schematic on the website. I tried to be organised by laying out the components by their values on post it notes :slightly_smiling_face:

A closer pic, took a while to get things laid out and then shaping the wires to reach each other ready for soldering.

The completed crossovers, really enjoyed doing this, something new … the day flew by.

A closer view again, the tweeter capacitors are pretty big. The two resistors next to each other on the left of each board allow the treble to be adjusted to your preference. If it turns out to be too much for me I can connect up the other one instead.

Here the wires have been soldered to the drivers (no push on connectors here!) which was quite nerve racking, and then the drivers mounted in the cabinets. Shame I didn’t take any pictures as these drivers really are beautiful pieces of engineering.

All the wiring done and more Acoustilux damping added, all that’s left to do is screw the bottom panel on! :grinning:

With my old speakers relegated to the corner and the new ones on the floor as I didn’t have any stands yet, I hooked them up to the 250. Quite nervously too!

They worked!! :tada:

A couple of days later with a version 2 of the temporary stands.

So that’s my first speaker build from start to finish.

As I’ve said before it has been incredibly rewarding, they sound wonderful and were a lot of work, but worth every minute.

First build … definitely not last :grinning:

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Very nice job!

How are they sounding now?

Fabulous work and much fun :sunglasses:

Incredible project, thanks for sharing.

Fantastic work Mark and really interesting to follow ( even with the break :man_shrugging:) your trials and trepidations :clap:t2: Best Peter

Thanks Peter, got there in the end, albeit with a detour in the journey! :slightly_smiling_face:

You’re welcome Martin, thanks, glad you enjoyed it!

Indeed! Thanks Mike.

Thank you! That’s a difficult question! Bearing in mind they’ve only been running for about a week and a half now, and I’ve not yet experimented with positioning, they’re settling in very nicely. Early on I felt I may need to move them further from the wall as I wasn’t expecting the bass they deliver, and maybe I’d try tweaking the treble down a bit. I no longer feel that I need to do either. The bass is still as deep and powerful but more controlled and the treble is lovely, so smooth and crystal clear. Vocals, male and female … wow, was listening to Louis Armstrong the other night and the texture of his voice was remarkable.

They are much better at lower volumes than my old speakers, which is going down well with my wife :slightly_smiling_face: I’ve been listening mostly around 8 on the volume, going up to 9 when I can but today I had the chance to crank it up! I had a bit of time between finishing work and having to pick my wife up from the station, just enough for a couple of favourite tracks … with volume at 10 :slightly_smiling_face: Stairway to Heaven was up first, I love the way this track builds up and it sounded exceptional, parts of this on my old speakers could sound a bit harsh at higher volumes, none of that now. Next up was Comfortably Numb, the album version, goosebumps and spine tingles … which I never really got before from this version, preferring the live ones. Only time for a bit of one more track, Metallica, Nothing Else Matters, intro guitar sounded amazing … first drum beat, well I literally laughed out loud it hit so hard, I knew it was coming of course but really wasn’t prepared for that, incredible, wish I’d been able to carry on, instead I drove to the station with a stupid grin on my face :joy:

Anyway this post has taken a really really long time to write, I’m listening to a slow jazz playlist and keep getting drawn away to listen … and that probably sums up all the waffle and over the top stuff above in one sentence!

Cheers,
Mark

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Lovely write up! Thank you for taking the time to write it, plus all the time to post the progress pics. Time to get saving I think, I really want to give one of Troels’s designs a go, both yours and other Mark’s results look fabulous, and by all accounts sound even better :smiley:

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A truly inspiring read Mark! I keep revisiting Troel’s site and I’m circling the idea of ordering and trying out the ScanSpeak Bookshelf-3WC kit, but I just wonder how they’ll work in the compromised space I have, which, I’ve moved it around a few times to try and optimise sound vs working environment. As there’s no try before you buy option I’m a touch apprehensive. Never say never though, as I have the 3WC page book marked!

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That’s awesome to read Mark. I’m glad you ended up happy with them. It will be interesting to hear your opinion when you complete the CNO Grande. Both the Scan Speak and Seas drivers use paper cones but there are definitely some differences in their sound signature. IMO the Scan Speak have a little more sparkle, or something I can’t quite put my finger on. The Seas always seem a little more neutral, however, both are incredibly smooth. My long term plan is to build another more recent construction with the Scan Speak drivers so I can swap out every now and again. Best of both worlds. Enjoy.

@YetiZone it’s funny that you posted that picture. I’m currently renovating my garage and was thinking about that construction to go with my Nait 5si on a some wall shelves in there. If you wait long enough I might be able to give some feedback.
I wouldn’t worry too much about not being able to try before you buy. I really don’t think there is a dud speaker on that site. Everything I’ve made has exceeded my expectations. Also, as a diy build you can tailor the speaker to suit your needs/ears by adjusting the treble level. As long as that speaker design description suits your requirement, that is.

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Any more info on that particular 3WC kit would be fabulous if you take the project on for your garage.

@Mark63 & @Mark84 Any tips on how to decipher the pricing structure on Troel’s site? There seem to be a bewildering set of options / specs on the pricing PDF, unless I’m missing something glaringly obvious, which is highly likely!

Thanks, I’m glad you and others have found it interesting and maybe inspired a couple more builds as @Mark84 did for me :slightly_smiling_face:

Cheers,
Mark

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