Doc modding Marantz imperial 7

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antonio66
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Re: Doc modding Marantz imperial 7

Unread post by antonio66 »

Must admit I like the idea of sphere's Stu, I know they are supposed to take away any 'boxiness' from the sound, although I don't know if any of your earlier prototypes suffered with that.
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karatestu (Mon May 31, 2021 8:09 am)

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Re: Doc modding Marantz imperial 7

Unread post by Firebug1 »

French company called Cabasse makes sphere speakers. They have long history sinne 50's, although they have made tradional speakers, also.
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karatestu (Mon May 31, 2021 8:09 am)
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karatestu
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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

antonio66 wrote: Sun May 30, 2021 1:49 am Must admit I like the idea of sphere's Stu, I know they are supposed to take away any 'boxiness' from the sound, although I don't know if any of your earlier prototypes suffered with that.
Along with my part time farming I do some garden design from time to time (amongst other things) and I do get more of a kick out of the curvy designs than the classical formal straight lined ones. But I am a symmetry freak too.

A sphere ( well, almost) will have a beneficial effect on diffraction I should think - if you agree with the work of Harry F Olson. When I changed my tweeter pod from a wooden cube to a foam rounded edge dice the improvement was extremely noticeable to me. I know the material changed as well from wood to foam.

If the same thing happens when the mid bass enclosure goes in a sphere then I would be in for a real sonic treat. I can't wait to hear what difference the spherical tweeter pod makes (if any) over the rounded edge dice shape. My head says it will be an improvement. I don't think there will be any difference to baffle step as with a bipolar opposing driver arrangement there is no baffle step loss to worry about. There is supposedly a bipolar dip in the frequency response somewhere but that is only apparent when you are on axis with the drivers. As mine are up and down firing then we are always sat off axis to the drivers.

Boxiness - I guess my designs all showed some form of it as when I tried the 12 inchers open baffle I did notice a change in that respect. I think the cube shaped enclosures were better sounding than the cuboid ones. If we take boxiness to also include cabinets singing along to the music then my crap chipboard enclosures had plenty of that :lol: It wasn't until I steel lined them and used ply for the baffles that I realised by how much.

I think a small sphere sat on top of a larger one looks very cool to my eyes. The problem is my wife likes traditional looking furniture and black spheres are far from that. It would help if I could veneer them but that is impossible. Also making them out of wood is not practical, well the 35cm sphere would be a nightmare.

I am very excited to try my spherical tweeter pods directly above the up firing mid bass like a kind of diffuser. I know they are not a complete sphere when the four tweeters are in but worth a try nonetheless.
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Re: Doc modding Marantz imperial 7

Unread post by Fretless »

As for aesthetics and WAF, Stu.

Could you consider mounting your spheres in an external metal frame, something like this:

Image

If your wife still isn't happy then you could cover it with thin speaker-grille fabric.

Might look really cool. 8-)
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karatestu (Mon May 31, 2021 9:21 am) • antonio66 (Tue Jun 01, 2021 1:35 am)

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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

Fretless wrote: Mon May 31, 2021 8:54 am As for aesthetics and WAF, Stu.

Could you consider mounting your spheres in an external metal frame, something like this:

Image

If your wife still isn't happy then you could cover it with thin speaker-grille fabric.

Might look really cool. 8-)
Excellent idea :dance: It will need a stand of some sort to get the down firing mid bass about 40cm from the floor and the tweeters up to ear level.

I will work on the wife in subliminal ways :twisted: I have increased powers now I have stopped drinking :grin:
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Re: Doc modding Marantz imperial 7

Unread post by Fretless »

Image
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karatestu (Mon May 31, 2021 11:46 am)

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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

Never looked at the price of these speakers. Hand made in Italy, yours for only £10,690. Just imagine the bragging rights that will get you :dance:

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Mid bass and tweeter are a bit far apart for my liking and the mid bass is firing the wrong way :roll: :roll: :naughty:
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Re: Doc modding Marantz imperial 7

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karatestu (Mon May 31, 2021 5:41 pm)
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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

Latteman wrote: Mon May 31, 2021 4:58 pm Image
BB8 :dance:
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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

Howz about this then ?
Image
Image
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Elipson BS50 tribute speakers. A modern take on the 1950's originals. A 8" up firing driver housed in a sphere with three legged stand and strange looking diffuser :shock:

Only £3.5k to you.
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CycleCoach (Mon May 31, 2021 6:53 pm) • antonio66 (Tue Jun 01, 2021 1:37 am)
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