Speaker build - CNO4

I was joking on Jof question about the rectangular plate in Mike’s speakers pic.
Just kidding.

As good as that, I had to get somebody in to finish it.

That picture is the punchline to:

“That’s not a port. This is a port”

Awesome thread. Got itchy fingers for a DIY project!!!

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Agree. But also, you can work around lots of constraints. I’ve (always in fact) worked on cars outdoors, using kerbs to get access underneath, without access to a jack, or stands. Although whilst lying in the gutter, struggling with the new exhaust for my very not new Audi, amongst the dust, with cars passing by, I do recall thinking I’d rather have a clean dry workshop to use X) It’s character building!

Working methodically, slowly, using outdoor space if/when weather allows. Storing tools in the meantime. I’m sure you could use a hand saw to cut speaker holes, if done v. carefully, or outsource to a shop.

And you can’t just jump to being an expert either. What we haven’t seen in this thread is the journey of the OP before this build. Or even any mistakes with this build! I bet there are mistakes along the way, the experience is all part of the enjoyment.

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Productive day today. Port holes routed, plate amp routed for, plus ventilation holes. Router dust extraction fitting delivered today, so routing is no longer a complete pain in the arse. Crossovers glued to boards. Tweeter hole routed and fits absolutely perfect. I measure and check these about 20 times before cutting!

These tweeters are really nice, the whole thing is aluminium or some type of alloy. Even the back. Not a bit of plastic in sight.

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Crossover.

Just needs soldering. Also need to grab some cable ties to strap down these coils. The big ones are 3kg each.
Jantzen Alumen Z caps.
The three resistors In a row are for tweeter level attenuation.

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If you look at the picture with the hypex amp being test fitted. In the bottom right of the cut out you will see my first mistake. Slightly too far with the router. Yes mistakes happen for sure. You just have to be careful not to make one on a really essential part. Measure twice cut once as the saying goes. Not always enough sometimes. Especially if you have a panel the wrong way round…then it doesn’t matter how many times you measure.

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Do you propose passive speakers, with no Hypex class D amp inside ?
Just curious.

The hypex amp will only drive the 12” bass driver in the bottom. This is rolled of at 80 Hz. The top section is driven by whatever amplifier that is plugged in. In my case, my Atom at the moment. It is a Semi active speaker.

At the speaker terminals the amp will be linked to the high level input.
The great thing about this is that the hypex will go down to 20 hz and has a dsp so the bass can be tailored for any room conditions.

Also the top section is a first order crossover.

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Yes, but some may not like the class D amp signature….just wondering

I get what you are saying but it is arguable that low frequencies do not carry the detail that portray the sound signature of the class d amp. Especially below 80 hz. I tried bi-amping my other speakers (now sold) with a hypex for the bass and it was very very good. Completely different to class d powering the mid/treble. These amps have very good control over the bass. It is not a worry for me. If for some reason it doesn’t work as hoped, there is also a passive crossover option for the bass section but the designer states that to get the full potential from the speaker the hypex is recommended. Have a read of his website if you are interested. He uses the EAR pre/ power , as you do.

What you have to remember is that the top section (6” +8”) receives and plays the full range signal from the naim amp. The hypex only supports the lower registers.

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Looks like it was done on purpose, could be the pry point to get the amp out.

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Thought about that too. But it’s only effective pretty low down, 80Hz plus whatever roll off its applies, wonder how much you’d be able to tell in real world listening?

Very interesting , thanks. Will look.

Can’t say honestly

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I believe the saying is

Measure it with a micrometer.
Mark it with a piece of chalk.
Cut it with an axe.

:upside_down_face:

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Front panel chamfering done with my rail saw. I was quite nervous for this part as I haven’t done it before. It went well.

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Additional 10mm panel added to front for time alignment of drivers.

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Routing for drivers. This is without a doubt the most tense part. One mistake and you have to start all over again. I have made a few mistakes on previous projects here. Many many cuts. All have to be spot on. Also the front panel is so thick that I had to route from the rear first.
Not shown in photos but there is also a 45 degree rebate on the rear of driver holes to aid air flow from the rear of the driver.

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All internal panels lined with compressed felt.

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