4 way Frankenstein high efficiency speakers

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Daniel Quinn
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Re: 4 way Frankenstein high efficiency speakers

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Personally I find it best to assume a person knows what they are doing , unless of course it’s me.

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Lindsayt
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Re: 4 way Frankenstein high efficiency speakers

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valvesRus wrote: Thu Dec 02, 2021 7:43 pm
Lindsayt wrote: Tue Nov 30, 2021 4:27 pm

I do not intend using MDF nor chipboard on my speakers.

So, does that mean you are likely to be using BBP ? (Baltic birch ply)

Regardless of the material, have you a plan as to how the different parts of each module (the cabinet that is) will be joined together?

Are you skilled in use of a router ?

If you are then tidy and accurate joints are assured, although you will need many and various clamps while the glue is drying.

Some folk like biscuit joiners, but I've not tried them myself.
I'm looking out for deals on plywood.

I have some floor joist offcuts that I intend using for the bracing. Then from there I reckon I'll need 4 off 8' x 4' sheets of plywood.
I'm thinking of having sandwiched layers for the front panels for the woofers.
Also been thinking about doing the Richard Dunn thing of having metal plates inside the cabs, or possibly just on the front panels.
I might go for external bracing as well as internal bracing.

If I had a large CNC router I'd do all machining operations on that. But I don't. So I'll be using more manual tools...

When I get my final pair of drivers I'll draw a set of plans to BS8888.
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savvypaul (Fri Dec 03, 2021 9:50 am) • SteveS57 (Sat Dec 04, 2021 12:37 am)

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r3xj0hn570n
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Re: 4 way Frankenstein high efficiency speakers

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Lindsayt
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Re: 4 way Frankenstein high efficiency speakers

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r3xj0hn570n wrote: Sun Dec 05, 2021 8:34 am How about these?

https://en.toutlehautparleur.com/haut-p ... m_store=v2
That has similar specs to other woofers I've been looking out for. SB Audience do an interesting 21" driver too.

What puts me off them, half joking, half serious is that AVI used SB drivers.
AVI were great for guidance on hi-fi. Whatever they said, do the opposite for best results.
Were there any driver types that AVI said were complete rubbish? Yes. 1960's EV & Altec. :guiness;

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Re: 4 way Frankenstein high efficiency speakers

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I've heard too many plywood loudspeakers and open baffles sing along with the music, I much prefer good quality chipboard.

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Lindsayt
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Re: 4 way Frankenstein high efficiency speakers

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Any links to sales of good quality chipboard?

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Re: 4 way Frankenstein high efficiency speakers

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Lindsayt wrote: Mon Dec 06, 2021 11:22 pm Any links to sales of good quality chipboard?
I tend to buy flooring grade chipboard lindsay, there's a local wood yard to me that sells decent off cuts, at one time they had lots of 25mm chipboard. There must be some where like that close to you?
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Lindsayt (Tue Dec 07, 2021 7:59 pm) • antonio66 (Wed Dec 08, 2021 2:10 am)

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Lindsayt
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Re: 4 way Frankenstein high efficiency speakers

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I've been doing some estimates on aspects of the design of these speakers.

The bass bins are likely to be in the ballpark of 35 kgs per channel. From the weight of the driver, weight of the cabinet skin, bracing.
The upper bass driver will be in a separate enclosure and the squawker and tweeter in a separate sub-assembly.

I intend making the speakers time-aligned. Similar to the Wilson Alexx speakers.
Or time aligned-ish. Because my drivers are all cones or domes and the listening distance and height may vary.
They will at least be more time aligned than if I mounted the woofers and horns directly onto 1 vertical panel.

The bass bin will probably have an internal volume of about 160 litres. Which would make it about 0.5 metres wide by 0.4 metres deep by 0.8 metres high.

For the front panel of the bass bins I'm thinking of going for front and rear mounting of the woofers. A 3mm aluminium plate on the outside, a 6mm sandwich filling, 18mm plywood on the inside.

For the bass bin bracing I'm thinking of making a mortise and tenon timber chassis.
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karatestu (Fri Dec 24, 2021 11:40 am)

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Re: 4 way Frankenstein high efficiency speakers

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I'm looking forward to seeing these take shape. Not enough speaker building going on round these parts.
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Lindsayt (Fri Dec 24, 2021 1:00 pm)
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karatestu
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Re: 4 way Frankenstein high efficiency speakers

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:epopc:
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