[78-L] 78 rpm stylus question

[Bryan Wright]

That's interesting, Jeff. I was trying to figure out how to get a  
frequency spectral analysis that would show the characteristics of the  
affected stylus. Thanks for taking a look and identifying exactly  
what's going on sound-wise. It's good to know that the "whistling" is  
at 10.9 kHz. That might be outside the range for many 78s from before  
WWII, but I also have quite a few great-sounding 78s from the 1950s in  
my collection, and many of those have a frequency range that I would  
guess goes well up to 20kHz. (Besides, I often prefer not to over- 
filter earlier records -- even if there's no recorded signal above  
10k, leaving just a bit of higher-frequency surface noise can trick  
the ear -- quite convincingly -- that there is! I may be something of  
a purist, but I prefer transfers that sound as "open" as possible, and  
to my ears, that usually means avoiding aggressive low-pass filters.)

Now I just wish I knew what in the physical makeup of a stylus  
assembly is causing this altered overall sound.

Bryan

On Jan 9, 2013, at 3:00 PM, 78-l-request at klickitat.78online.com wrote:

> I downloaded the clip and analyzed it using Sound Forge. The  
> portions that were played with the problem stylus have a 5 dB peak  
> at about 10.9 KHz, followed by a 13.5 dB trough at about 11.2 KHz.  
> This is enough to be audible. I don't know what causes the problem,  
> but since there's no recorded signal at those frequencies you should  
> be able to eliminate it easily with a low-pass filter.
>
>> Yes, the issue here is a "ringing" or high-pitched "whistle" that is
>> present in the affected stylus. . .