Thank you for the advice, and for uploading a sample file with the modifications. I wanted the opinions of people more experienced than me, and I appreciate it.
You’ve confirmed the same results I’ve been getting: any decrease in noise/popping also decreases intelligibility. I think I’ll give the recording to my Aunt, as is, and let her do with it as she will.
Do you still have the record? There are published techniques to force a modern phonograph to play a 78 and then “convert” the result back to real time and pitch, but there’s just nothing like playing a 78 at 78 with a 78 size needle which is much less likely to pick up clicks, pops and groove noise. The narrow LP needle rides along on the bottom of the 78 groove picking up all the cat hairs and dirt down there.
So if this is one of those speed conversions I think you can do a lot better playing it the way it was supposed to be played.
That’s why I said it isn’t ideal to use a modern stereo stylus.
However, one has to be open minded.
The advantage of a variety of different styluses is that they ride on different levels of the groove and you can combine the recordings and isolate what’s common to all of them.
It’s even possible to have the same stylus but different weights.
It seems to me that the recording of this topic is already at the end of its life span and I would apply all possible means to preserve the contents digitally.
The best way would be a pure visual, microscopic inspection of the groove but who could afford this procedure?
It is fairly controverse; should one record in stereo or not?
One guy says in his comment that he mixes down to mono in order to eliminate clicks on one side of the groove.
However, the reduction is maximally 6 dB with this method, whereas center isolation reduces the extreme sides by inf dB.
The following sample file has those settings applied:
mixed to mono
with center isolation and strengths of
1.0, 2.0, 3.0, 4.0, 5.0 and 50.0.
The last setting is certainly not suited for music as it creates bubbly artefacts (since the pan position is not 100% in the middle. )