Thanks for the technical information.
I don't intend to become an intense 78 RPM shellac record collector. I just want to be able to play a couple of records that I was given. I don't expect the sound to be high fidelity. I am doing this for the novelty.
The two records I have are from about 1950 and about 1916.
Isn't stylus radius much more important than equalization or speed? Doesn't the playback stylus radius have to be similar to the cutting stylus radius? By how much did stylus radius vary around 3 mil compared to an approximately 1 mil microgroove stylus?
By how much did the equalization vary? Wouldn't it be possible to simply compensate with tone controls if absolute accuracy is not an issue? What are equalization "codes" and how do they relate to equalization time constants?
The technical aspects of 78 RPM records do not change the fact that LP Gear has poor customer service and stole my money.
Yes, the stylus radius is very important. If you use and LP stylus the tip goes to the bottom of the groove and ruins disc and stylus, so you do need a 78 RPM stylus.
The 1950 disc should play OK. The 1916 disc is prior to electric recording and so is a purely acoustic recording. The artists would have sat under the mouth of a huge horn, and the sound waves drove the needle of the wax master cutting lathe. Then the mother and and stamper were prepared from that. That disc will be faint and distant, and probably be more noise than program. The shellac discs then were all played either with steel needles, which you changed after each disc playing, or a fiber needle that you sharpened on devices like this.
Here is data on some 78 RPM groove sizes. You can see one outlier there, but most of the majors were close.
Here is further information for you.
LP gear should refund your money. The problem is there are all kinds of secondary manufacturers of varying quality. As I understand it, AT do not make those 78 RPM styli, so I am not surprised, some just "fit where they touch".
When I was four years old, my father gave me a an acoustical HMV gramophone made by a subsidiary of HMV in India. He brought it back from India after the WW II.
It took all my strength to wind the spring. I had a fiber needle sharpener similar to the one above. I had tins of steel needles, and uses to look at the groove and estimate the correct size. Age 7 I graduated to a pre-WW II HMV radio gram, so no more spring winding. However I quickly started to experiment with external speakers and in no time I was going full "Monty" building speaker enclosures and tube amps. I was addicted for after that and have never stopped.