Turntable resonance

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Daithi
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Turntable resonance

Post by Daithi »

Is the turntable part of the soundscape in these machines?
Some turntables are very sonorous, almost bell like.

OrthoFan
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Re: Turntable resonance

Post by OrthoFan »

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Last edited by OrthoFan on Sat Apr 04, 2020 7:43 pm, edited 1 time in total.

Daithi
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Re: Turntable resonance

Post by Daithi »

I wonder if the designers of these machines deliberately made the turntables and cabinets to produce sound.
As luck would have it, I have two almost identcal turntables. One sounds like a live thing and the other is a dead thing. A sonic comparison of the two is in my future.
My friend has a guitar that sits to one side of her TV about two yards distance. It resonates everything from the TV.

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AudioFeline
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Re: Turntable resonance

Post by AudioFeline »

Adhesive dampening material (eg. Dynamat) has been used to dampen unwanted resonances in modern turntables. However, over-dampening can suck the life from the music. You can experiment with this, as if you over-do it it can be removed.

Daithi
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Re: Turntable resonance

Post by Daithi »

AudioFeline wrote:Adhesive dampening material (eg. Dynamat) has been used to dampen unwanted resonances in modern turntables. However, over-dampening can suck the life from the music. You can experiment with this, as if you over-do it it can be removed.
So the turntable resonance is a factor in the production of sound by a gramophone ?

VanEpsFan1914
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Re: Turntable resonance

Post by VanEpsFan1914 »

I don't know about that, it seems like on a gramophone there is just too much of an essentially crude & mechanical system for the fancy turntables to matter. Is that true or no?

Daithi
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Re: Turntable resonance

Post by Daithi »

VanEpsFan1914 wrote:There is just too much of an essentially crude & mechanical system for the fancy turntables to matter. Is that true or no?
I don't know enough. I just wonder why some turntables, most actually, ring like a bell and the original designers did nothing about that. It wasn't an issue for them or they were actively persuing it.

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AudioFeline
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Re: Turntable resonance

Post by AudioFeline »

The design, construction and materials all combine to determine if there are unhelpful resonance in a system. The degree that these were in a reproduction system depends on the knowledge available during the era they were constructed, and other constraints (eg. materials available, construction techniques and cost). Some resonance may be helpful, and bring life to the reproduction. Whereas other resonance may be unhelpful, bringing unwanted peaks into the frequency response or detracting from the clarity of sound. I'm not an expert in these early systems, but I would imaging there are lots of places which could be contributing to the sound quality and may provide opportunities for improvement (eg. strengthening cabinets, selected dampening to the horn, etc).

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Marco Gilardetti
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Re: Turntable resonance

Post by Marco Gilardetti »

Daithi wrote:I don't know enough. I just wonder why some turntables, most actually, ring like a bell and the original designers did nothing about that. It wasn't an issue for them or they were actively persuing it.
I would resolutely exclude the latter. The technology deployed in gramophones tells us that engineers at least tried to do something to dampen resonance and halt soundwaves mechanically propagating through the machine's body. The felt covering the turntable and the rubber isolators between soundbox and tonearm are the most evident ones. These may look largely insufficient by today standards, but were "good enough" at the times as the gramophone had much larger issues to be solved in terms of fidelity. They clearly show, in any case, that they considered and tried to put a limit to issues concerning resonance.

Daithi
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Re: Turntable resonance

Post by Daithi »

Marco Gilardetti wrote: The technology deployed in gramophones tells us that engineers at least tried to do something to dampen resonance and halt soundwaves mechanically propagating through the machine's body. The felt covering the turntable and the rubber isolators between soundbox and tonearm are the most evident ones. They clearly show, in any case, that they considered and tried to put a limit to issues concerning resonance.
So a dead turntable would be preferable to a live one?

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