Is it possible the lathe had a mechanical problem and a LF vibration from 
the motor, a bearing, idler wheel etc was cut into the wax?

Tim Gillett
Perth,
Western Australia


----- Original Message ----- 
From: "Paul Stamler" <[log in to unmask]>
To: <[log in to unmask]>
Sent: Sunday, August 13, 2017 12:22 PM
Subject: [ARSCLIST] Oddball record


> Hi folks:
> 
> I'm working on a record that has me puzzled. It's a Gennett record from 
> 1923. The authorities say that Gennett didn't take up electrical 
> recording until 1926 or so, so I had  this pegged as acoustic.
> 
> But it has *hum* on it. Significant hum; at this stage in processing the 
> signal (two channels combined, no EQ, iZotope de-clicking applied) the 
> hum signal is at about -38dBFS (about 24dB below my nominal 0vu level). 
> There's also an intermittent signal at 40Hz. The lowest signal frequency 
> seems to be about 150Hz
> 
> If this is an acoustical recording, how did those low frequencies get 
> onto the record? If there was a mechanical rumble in the room, I would 
> not expect the recording horn to respond significantly at 57Hz, let 
> alone 40Hz. (Heck, 150Hz is surprising.)
> 
> And the thing is, it doesn't *sound* like an acoustical recording -- 
> there aren't the typical horn resonances coloring the sound. It sounds 
> like a good early electrical recording.
> 
> But the 1923 date is reinforced by several sources -- well before 
> Gennett is believed to have gone electric.
> 
> Could this have been an experimental electrical recording (perhaps using 
> the GE Photophone process) that somehow escaped into the catalog? Could 
> it be turntable rumble during cutting? If so, why does the record sound 
> electrical rather than acoustical?
> 
> By the way, the flip side has virtually identical hum, though a cursory 
> glance doesn't show the 40Hz component.
> 
> Anyhow, I'm mystified. I know that record companies were experimenting 
> with electrical disk recording before the majors adopted the Western 
> Electric system, hence my speculation that this could have been one of 
> those experiments.
> 
> Any ideas?
> 
> Peace,
> Paul Stamler
> St. Louis
> 
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