[78-L] Groove spacing - groove width

[Mark Bardenwerper]

On 11/19/2016 6:53 AM, Mark Bardenwerper wrote:
> On 11/19/2016 4:53 AM, Kristjan Saag wrote:
>> When recording went electric one of the consequences was the ability to
>> avoid overcutting - it became easier to control loud signals. Thus
>> groove spacing was affected: the number of grooves per inch or
>> centimetre was increased, recording time per disc side could also be
>> increased.
>> But apart from groove spacing - is there any evidence that groove width
>> was affected as well? As we know different record companies used
>> different groove width both before and after the advent of electric
>> recording, and it's also clear that groove width generally decreased
>> with time. But I've seen no mention of a major change haven taken place
>> due to electric recording.
>> Does anyone know more about this?
>> Kristjan
>>
>>
> I think it is more likely that you will discover that the width of the
> grooves did not change appreciably, but the ability to do some sort of
> equalization allowed the grooves to be crowded in better. The slowest
> change was on the playback end. This seemed to hold back progress more
> than anything else, particularly in sight of the hardships created by
> the depression.
>

Recording time was first seen as a significant factor in movie sound 
recording. Vitaphone began distributing 16 inch, 33 rpm records in 1929 
or 30, with standard groove width.

There were several advantages to vertical cut. Spacing could be 
standardized and equalization was not as big a factor. Edisons were gear 
driven and it was the lack of portability and the stranding of the 
technology that ended Edison. Vertical records were still used in radio 
transcription for a long time, where playing time remained important. 
Smaller grooves came first to transcription, I think. The big change in 
groove width had to wait for the end of WW2 for the general public, 
though RCA introduced a short-lived special line of players and records 
in late '31.

Someone will chime in with better details I am sure. How accurate is 
this info?

https://en.wikipedia.org/wiki/LP_record

-- 
Mark L. Bardenwerper, Sr.

Technology...thoughtfully, responsibly.

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