Why use a mono cartridge
Debunking LP Record Weights and Clamps
by George Merrill
Holding the record to a damping material is the job of weights and clamps. An LP record's label is thicker than the vinyl playing surface. The label varies from approximately 20 to 60 thousandth of an inch thicker than the vinyl. A record mat will have a depression in the center to allow the record vinyl to lay flat, otherwise, the label would be the only contact point. If a center weight is used that is very heavy, let's say 2 lb. the lighter records will lift from the mat. This happens because the mat depression edge will act as a fulcrum. This information tells us we should use a center weight tuned for the record thickness and weight. However, this is impractical. Here is the solution: Use a center weight that weighs 8-12 oz . This weight will work with all but the lighter records. The alternative to a weight is the screw-down clamp. These clamps have pluses and minuses. The plus is downforce on the record can be controlled. The minus is if not designed properly (unfortunately, most are not), spindle energy is coupled into the record. It takes very little intrusion of external energy to cloud the mechanical output of the stylus. (I wrote a paper on proper screw-down clamp design over 30 years ago.)
The best answer is the periphery clamping weight along with a center weight. The weight balance between these two should be calculated for even and optimal downforce on the entire vinyl area.
As the stylus traces the groove, energy is radiated in all directions; as it reaches the periphery of the record, it is then reflected back into the groove area. The periphery clamp will help damp this edge energy before it is reflected into the groove area. The center weight also acts as a damper. The first production periphery clamp was used on the Merrill Heirloom Turntable 1980. Kenwood also introduced theirs about the same time. Other manufacturers are now discovering the benefits of this type of clamp system.
The Phono System Chain
What Should I Purchase first?
by George Merrill
"The Heart of the System is the Start of the System"
The RIAA’S recording equalization The RIAA recording equalization curve was adopted in 1954.Before that date 100 + different turnover points were used within the industry. What the RIAA EQ curve accomplishes is:1 Allows more recording time. (approximately 22 minutes per side)2 Reduces the vinyl noise. At the time of recording the low frequencies are cut (more space = more time) and the high frequencies are boosted.At playback the low frequencies are boosted and the high frequencies are cut (lowering the noise floor of the vinyl).The turnover points are: 50 - 500 - 2122 HZ