Larger Semi-Omni Development

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Dave the bass
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Re: Larger Semi-Omni Development

Unread post by Dave the bass »

Heh! I might have to call in at other AT members houses on the way up for a pee pee and to collect other unfeasibly heavy loads for my back pack!

Mind you, I'd be very fast coming back down country though wouldn't I cos its all downhill....

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wiicrackpot
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Re: Larger Semi-Omni Development

Unread post by wiicrackpot »

Dave the bass wrote: Sun Jul 02, 2017 10:02 am Heh! I might have to call in at other AT members houses on the way up for a pee pee and to collect other unfeasibly heavy loads for my back pack!

Mind you, I'd be very fast coming back down country though wouldn't I cos its all downhill....
Epic !!, :handgestures-thumbupleft: you'll have to name it RAB (Race Across Britain),
did you know about the untimely death ultra cyclist Mike Hall a few months ago in the inaugural Race Across Australia?,mown down by a redkneck on the penultimate day,
he was complaining to race organisers days before about the near misses that he had on that trek. :(
Frank...made me do it.

Dave the bass
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Re: Larger Semi-Omni Development

Unread post by Dave the bass »

Yeah, I read about Mike Hall, that was bad, though I have to 'fess up that I don't follow any Sport, even cycling. I just like riding ol' crappy bikes myself as far as I can. I don't like watching others do it. I think I lack the sport hormone.

Sorry for hijack Steve, I'll shurrup now.

PS. Get building :)

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SteveTheShadow
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Re: Larger Semi-Omni Development

Unread post by SteveTheShadow »

wiicrackpot wrote: Sun Jul 02, 2017 9:16 am Steve, your 'banned flatbacks', is it suitable for other drive units?,
i have a pair of PHY Type:B252-8, SP: 3000 drive units gathering dust fro 10 years or so,
was thinking if that can replace the one you use to make use of it.

Edit: just had a perusal on the Faital Pro 6PR110, seems the PHY's are that far away spec wise,
cept a bit larger at 8'inch. :think:
The cabs aren't going to be suitable for an 8" driver. They would have to be completely re-designed for those driver characteristics.
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SteveTheShadow
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Re: Larger Semi-Omni Development

Unread post by SteveTheShadow »

Dave the bass wrote: Sun Jul 02, 2017 10:25 am
PS. Get building :)
I'm going as fast as I can (which at my age is a bit faster than a snail, but slightly slower than a tortoise) :lol:
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Somebody’s stepping on my plastic sandals. Joe Jackson (1979)

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SteveTheShadow
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Re: Larger Semi-Omni Development

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Dave the bass wrote: Sun Jul 02, 2017 9:40 am
...... and an OP TX.... use it...or I'll cycle up to your house and claim it back :)
Trouble is Dave, I haven't got any bloody valves now :shock: :cry:
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Thermionic Idler
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Re: Larger Semi-Omni Development

Unread post by Thermionic Idler »

SteveTheShadow wrote: Sun Jul 02, 2017 11:08 am
Dave the bass wrote: Sun Jul 02, 2017 9:40 am
...... and an OP TX.... use it...or I'll cycle up to your house and claim it back :)
Trouble is Dave, I haven't got any bloody valves now :shock: :cry:
You'll have to change your avatar then :lol:

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SteveTheShadow
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Re: Larger Semi-Omni Development

Unread post by SteveTheShadow »

Yes, I suppose I will have to change it. :-?
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SteveTheShadow
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Re: Larger Semi-Omni Development

Unread post by SteveTheShadow »

OK,
Have acquired a pair of Doc modded, doped, cheap, Chinese 12" bass drivers for the bottom cabinets.
The size of the magnets which will give a high total Q factor and the lower resonant frequency introduced by the added mass of the doping ought to, in theory, make them very suitable for sealed box (acoustic suspension) loading.

The proximity of the drivers to the floor (about an inch above the carpet) should give smooth bass response and the lower efficiency of the bass cabinet to that of the mid/treble cabinet, should give a nice balance top to bottom after the influence of the floor boost and rear wall proximity is taken into account.

It is much better IME of designing speakers, if you design in a lower bass level, then boost it by having the cabinets nearer the wall, than it is, to have a high bass level and then have to reduce it by having to site the speakers in the middle of the room.

Old-fashioned and complete anathema to imaging freaks it may be, but we have to remember that this design (as are all my designs) is meant to cater for people with normal domestic arrangement requirements, rather than those folks lucky enough to have a listening room of their own.

Again we are using the room with this design rather than trying to deny the fact that all speakers have to operate into a real acoustic space unless they are being used as a PA at an outdoor festival.
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Dr Bunsen Honeydew
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Re: Larger Semi-Omni Development

Unread post by Dr Bunsen Honeydew »

Pleased to help. Conceptually Steves designs will get my full support and will obviously be very suitable for NVA amps same as Cubes. Reason, another person who has read Roy Allisons papers and understands them and the concept. Quite simple the speaker and the room form one entity, they should work together not fight each other, common sense don't you think?

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