Merrill Hierloom and speed control
If you don't have an external speed control and rely on the pulley then I recommend
finding an app for your smart phone ( RPM ) and test your speed.
My Merrill is an early model # 135 with only a 33 1/3 pulley and have been wanting to add 45 rpm as an option because of all the new recordings coming out on the 45 rpm format.
I tried to purchase a new pulley from MRS but it out of business,
my next option was spending more money to purchase a Phoenix Engineering speed control
and they went out of business. I was left with one option a GEMS speed control.
A very good option but also expensive and hard for me to justify even though that was my only option if I really wanted to be able to play the new 45 rpm albums.
I had read about an app that lets you check your speed so I downloaded it and discovered I was almost 3% slow, So that day I ordered a speed control from George Merrill himself.
Needless to say everything sounds better than ever.
Moral of the story you can't count on 60Hz being 60Hz exactly ,
plus this is much better than taking the plater off and moving the belt on a duel speed pulley.
Thank You Mr. Merrill