While I understand the importance of capturing output "above 20kHz" with
the aforementioned tools, are there any tools available to help with
azimuth adjustments?  Older recordings, especially those made in the field
with machines that have been "banged up", may be recorded with azimuth that
is slightly off.  Therefore, the higher frequencies may be lost or
diminished if playback is not adjusted to the exact azimuth of the original
recording.  Is the only tool available our ears listening as we manually
adjust the azimuth?

On Fri, Aug 29, 2014 at 6:18 PM, John K. Chester <[log in to unmask]> wrote:

> At 04:49 PM 8/29/2014, Tom Fine wrote:
>
>> John, is there a modification for to remove those noises? Do 3rd party
>> electronics also carry those noises or are they something with the power
>> rails under the transport? Sorry if these are ignorant questions, I'm not
>> that familiar with the innards of ATR's.
>>
>
> I suspect this is neither the list nor the proper subject heading for
> discussing such a highly technical issue, but here's a brief answer:
>
> I have never tried to clean up an ATR with stock electronics, although I
> have a good idea of where to start.  I have no data on 3rd party
> electronics other than Plangent's.  When I got the Plangent electronics to
> be clean enough for our purposes, I stopped worrying about the problem.
> Plangent does use a preamp in the headblock with a cable running directly
> to our box, which helps keep things clean.
>
> I do find it a bit odd that folks doing 192k transfers often don't seem to
> worry about how much signal gets from the tape to the tape machine output
> above 20 kHz, and how much noise in that region comes from the machine
> rather than the tape.  There are useful signals up there, and we know that
> if the transfer captures them they can later be used to improve the quality
> of the audio below 20 kHz that we can actually hear.
>
> -- John Chester
>
>
>
>  ----- Original Message ----- From: "John K. Chester" <[log in to unmask]>
>> To: <[log in to unmask]>
>> Sent: Friday, August 29, 2014 4:33 PM
>> Subject: Re: [ARSCLIST] recording "cleanup" plugins and 192/24
>>
>>
>>  At 05:06 PM 8/29/2014, Shai Drori wrote:
>>>
>>>> So if I turn the display off the 28.8 kHz goes away?
>>>>
>>>
>>> No, that noise on an ATR is actually coming from the reel motor
>>> drivers.  The display generates other noise which starts somewhere in the
>>> mid-50's of kHz and has lots of harmonics.
>>>
>>> Turning off the display removes a lot of the noise spikes in the audio
>>> output but not all of them.
>>>
>>> -- John Chester
>>>
>>