Howdie...
I am using an ACT/2 reproducer which many have told me produces good results. http://nipperhead.com/act/ I have a custom built prototype phonograph machine http://hertz.onlinepeople.net:801/phonograph/ that uses a very quiet ac servo motor and an edison home 2/4 minute top works.
The top works is very stable and concentric. When observing the mandrel it is rock steady at any speed from 30 RPM through 240 RPM. However, when I place a cylinder on the mandrel, the cylinders have their own slight eccentricity (even my best condition cylinders have some slight eccentricity). This ever so slight abberation in the cylinder seems to be causing really bad rumble on the recordings. I mean really bad! And the rumble that I am getting is a direct function of the eccentricity of the cylinder. It is not any noise being transmitted from any part of the mechanical train.
So here are my questions:
1. For cylinders that are vertically cut, and considering the eccentricity is also vertical in orientation, is it ever possible to isolate and eliminate rumble? (other than using filters at the rumble frequency or other digital rumble filters that still seem to leave plenty of rumble --I've tried a few such as sound laundry).
2. Anyone have experience with the ACT/2 reproducer? I am assuming it is rewired for vertical cut grooves, but haven't been able to get in touch with the guy I bought it from.
3. What do people on this list do in this situation? Some of you have archeophones. While I know there are adjustments for eccentricity, I find that the ends of the cylinders typically problematic but the centers (ie 2 minutes into a 4 minute cyl) seem much quieter in this regard. So for archeophone users do you have rumble problems?
If anyone is interested, I could probably post a sample audio file with the rumble present, but it is a lot!
Thanks in advance
Eugene