Tannoy Enclosure

Dedicated to those large boxes at one end of the room
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ed
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#76 Re: Tannoy Enclosure

Post by ed »

contrary to what Nick says, resistance is futile....go on, have a rant.
There's nowhere you can be that isn't where you're meant to be
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Ray P
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#77 Re: Tannoy Enclosure

Post by Ray P »

izzy wizzy wrote: Wed May 12, 2021 8:28 am Bought some clamps and glued up in stages.
Right tools for the job - result every time! Good outcome :thumbup:
Sorry, I couldn't resist!
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Ray P
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#78 Re: Tannoy Enclosure

Post by Ray P »

ed wrote: Wed May 12, 2021 9:31 am contrary to what Nick says, resistance is futile....go on, have a rant.
If you have an up and down sort of day should you feel impeded?
Sorry, I couldn't resist!
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izzy wizzy
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#79 Re: Tannoy Enclosure

Post by izzy wizzy »

Thought I'd try and summarise where I've got to with this. All I've read pointed to these drivers liking a large box and contributers who know things were hinting at similar. In the end they ended up about 1200mm high, 600mm wide and 400mm deep for about 220l volume. Yes they are big but I was aiming for something smaller than the corner Yorks; well they're narrower and less deep.

The tuning proved to be a big guess so in the end I made it flexible. It was going to be 3 ports that I could block off if needed but I couldn't settle easily on a configuration so then tried ideas around a rectangular one divided into three but while making it thought I'd try just one rectangular with inserts laid in it to reduce its area if needed. Prevarication in this area I know little about wasn't getting the cabinet made so opted for 18mm ply screwed together with the whole port removable to alter for future.

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Boxnotes was used to see what internal resonances were up to and to determine placement of the speaker on the baffle. Dimensions were wiggled to make the internal modes spread out and not repeat themselves. This lead to the speaker being slightly offset on the baffle.

The cabinet is made from 24mm BB ply with very little left from 2 sheets. It's a very nice material to use especially for a non wood working person like me. I wanted to try and make the cabinet without battens so all the joints are housed of varying kinds. Have been amazed at how accurate woodworking can be with a router.

There is no bracing. I imagine an experienced box maker would have recipes that include them but from what I can make out it's an imprecise area and bracing isn't always a positive hence none for now. In this cabinet the driver mount twisted before I noticed but by that stage there was glue and screws involved so left it as is.

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Damping is for now minimal. Have gone for a 600mm square of roof insulation covered with polyester wadding behind the driver to absorb stuff that could bounce back at the cone and a pile of similar in the bottom to try and reduce the major top to bottom node and that's it for now.

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The crossover is external as before and wires taken out on a Speakon connector. I've heard good reports of earthing the driver chassis and I will try that with a binding post as Tannoy do in their latest speakers.

The cabinets will be veneered but that may be in about 3 to 4 months time as the speakers and rest of the sound system gets shipped to NZ in 2 weeks.
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izzy wizzy
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#80 Re: Tannoy Enclosure

Post by izzy wizzy »

Have over 1/2 sheet of 18mm ply left. Do any of the speaker box builders have suggestions for bracing?
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#81 Re: Tannoy Enclosure

Post by chris661 »

izzy wizzy wrote: Sat May 22, 2021 10:59 am Have over 1/2 sheet of 18mm ply left. Do any of the speaker box builders have suggestions for bracing?
Join opposite panels, to stop the cabinet inflating like a balloon. Cut holes in the brace to regain some cabinet volume without sacrificing (much) strength.

You could also make the bracing dual-purpose by arranging it as you might position a deflector, thus breaking up some standing waves.

Chris
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