Doc modding Marantz imperial 7

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savvypaul
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Re: Doc modding Marantz imperial 7

Unread post by savvypaul »

Mid Century Danish modernism doesn't strike me as your bag, Stu...tbh
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karatestu
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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

I really don't know what I want at the moment. Pain can do strange things to the mind. One day I think what I have made is the best thing ever and the next day all I can do is find things wrong with it (aesthetics aside ;) ). Still enjoying the music though. Listening to Ghost in the machine through my party speakers and loving Sting's bass playing.

I quite like the look of the B&O stuff and that Ruark jobbie. Most of the stuff I have made looks like it was made using a chainsaw and nailed together with a sledge hammer in a shed by a farmer with limited intellect. That's probably because it was :lol:
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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

Infinity Holsonic speakers from the good old 70's. Can't remember if I have mentioned these before :think:

A transmission line loaded front firing 12" woofer run full range (no filter). This hands over to five tweeters fring front, back, up and to both sides. Sound familiar ? No up firing mid bass though. Those tweeters must be playing very low in frequency :shock: and the 12"must be beaming like a tannoy DC at crossover :shock: :shock:

Brochure found here for anybody interested

http://www.infinity-classics.de/mode ... other.htm
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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

Isobaric bass loading is alive and well in the speaker industry. Neat acoustics use the concept throughout most of their range but they port them :roll:

Look at this £19K pair :shock:

http://neatacoustics.com/ultimatum-xl10/

I did find some speakers that do it with midrange as well but forgotten what they are :think: Doing it with the midrange is said to be not a good idea. Doc said it wasn't a problem, Linn did it with the sara.

Apparently there are a few issues. As the air volume between the cones becomes larger the isobaric loading stops working progressively lower in frequency. Also there can be resonances in the mid band and when the distance between the cones is the same as a particular wavelength being produced there can be cancellations.

Nobody ever complains about this with the Cubix speakers do they ? And they have a lot of volume between each driver and equal amounts behind each driver. It is just a frequency response problem and spoils pretty graphs then. If you do the clamshell configuration then you are minimising the air volume between the cones especially if they are filled up nearly to the surrounds with dope.

Pity nobody has come up with a way to totally fill (with suitable product) the cavity between two drivers mounted clamshell (cone to cone) without it touching the rubber surrounds.
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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

Found it. Isobaric loading gone mad :shock: These speakers are ridiculously expensive.

http://egglestonworks.com/products/the-ivy-signature/
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Re: Doc modding Marantz imperial 7

Unread post by Daniel Quinn »

It can't be ported and isobarik. Neat must know this?

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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

The rear chamber can be closed, ported or aperiodic apparently.
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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

Forgot transmission line as well.
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Re: Doc modding Marantz imperial 7

Unread post by karatestu »

Quote from another forum
gedlee;6366300 wrote:I wanted to add some results from a paper that I reviewed recently for JAES.

The authors looked at brain activity while listening to a common music passage through differing headphones. The "flatter" the headphones response was the lower the brain activity. This strongly supports the idea that poor frequency response can lead to fatigue as the brain has to work harder to make sense of the sound signals it is receiving.
I sometimes get listening fatigue but usually when I am ill, stressed or just not in the mood. Maybe I should be aiming to design some table flat frequency response snooze inducing music killers ?
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Re: Doc modding Marantz imperial 7

Unread post by Daniel Quinn »

Listening to music plays a part in my rehabilitation. My right foot still doesn't move. But that fact belies a whole host of recent changes.

When I listen to music, my foot doesn't move, but my brain tells me and it feels like it is tapping.

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