Interesting Article on Time-Phase Coherence

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Lindsayt
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Re: Interesting Article on Time-Phase Coherence

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Why? Because the first, in phase one sounds like an annoying test signal.
The 2nd, out of phase one sounds like a slightly more annoying test signal. To my ears when played through my laptops internal speaker. The difference between them is unimportant to me.

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Re: Interesting Article on Time-Phase Coherence

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Given that a human female voice, for example, has fundamentals in the 300hz to 1khz region with harmonics then up to 8khz region and then with a spot of air on top, I would have thought that phase coherence across two or more drivers was essential as without it the probability of phase induced nulls and troughs would mean that the end result would be further away from what the recording engineer and artist intended.

This is probably one of the things drives some towards single driver systems. However, I've yet to be convinced by a single driver solution for the kind of music I like to listen to: they just don't seem to be able to hack anything complicated or needing a lot of welly: Mahler at full tilt needs to move a lot of air.

Simon Hickie
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Re: Interesting Article on Time-Phase Coherence

Unread post by Simon Hickie »

The equivalent in photography is the arrival points of different colours of light on the camera sensor. A poorly corrected lens where the light from a point in a scene is spread over too wide an area on the sensor will be manifested typically as a chromatic aberration (typically purple/green or red/blue fringing) and lack of definition or sharpness.

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Dr Bunsen Honeydew
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Re: Interesting Article on Time-Phase Coherence

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Good analogy.

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Dr Bunsen Honeydew
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Re: Interesting Article on Time-Phase Coherence

Unread post by Dr Bunsen Honeydew »

Lindsayt wrote:Why? Because the first, in phase one sounds like an annoying test signal.
The 2nd, out of phase one sounds like a slightly more annoying test signal. To my ears when played through my laptops internal speaker. The difference between them is unimportant to me.
Of course it is unimportant because it is test signals, all it did was prove a difference exists not what that was. For me it seemed to effect dynamic (level of volume) more than anything else. Now because a difference can be accepted by them on a technical basis I am *trying* to get them to move it along to music, with little success so far, it would be nice to have pressure and back up for the making of test speakers.

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Re: Interesting Article on Time-Phase Coherence

Unread post by Lurcher300b »

Lindsayt wrote:Why? Because the first, in phase one sounds like an annoying test signal.
The 2nd, out of phase one sounds like a slightly more annoying test signal. To my ears when played through my laptops internal speaker. The difference between them is unimportant to me.
Its not in and out of phase, the first one has all the harmonics in step, the second has then at 5 degree offsets. The point is you (or at least I) can hear a difference when it seems many would say you wont.

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Re: Interesting Article on Time-Phase Coherence

Unread post by Colin Wonfor »

https://archive.org/search.php?query=Ti ... 0Coherence

Some more bed time reading for you all, until Radio 4E bring back good night time comedy.
It can be done so imagine it.

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Re: Interesting Article on Time-Phase Coherence

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Simon Hickie wrote:Given that a human female voice, for example, has fundamentals in the 300hz to 1khz region with harmonics then up to 8khz region and then with a spot of air on top, I would have thought that phase coherence across two or more drivers was essential as without it the probability of phase induced nulls and troughs would mean that the end result would be further away from what the recording engineer and artist intended.

This is probably one of the things drives some towards single driver systems. However, I've yet to be convinced by a single driver solution for the kind of music I like to listen to: they just don't seem to be able to hack anything complicated or needing a lot of welly: Mahler at full tilt needs to move a lot of air.
Single drivers seem a logical way to go I have heard good reviews of the Ted Jordon speakers and wasn't he a designer at Goodmans in the Glory days

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Re: Interesting Article on Time-Phase Coherence

Unread post by Dr Bunsen Honeydew »

Single drivers just don't work, you are trying to give them too much work to do and the compromises are too large.

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Re: Interesting Article on Time-Phase Coherence

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Dr Bunsen Honeydew wrote:Single drivers just don't work, you are trying to give them too much work to do and the compromises are too large.
I'd love for you and Steve from electricbeach to get together http://www.electricbeachaudio.com/ whilst I understand you may have differing solutions for the same stated aim i.e. MUSIC you both also dont seek to rip anyone off --- the Frugal probably isnt best suited to doc mods but having heard the benefits of steel plating etc and also been amazed at what Steve's speakers can deliver -- I'd love to see what you two combined could come up with ....

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