Setting Up the Turntable

I have seen a couple of turntables out there that come with the table, the tonearm, the cartridge, and a USB connection for your computer that will let you turn your LPs into MP3s. The cost of the entire package is $149. Those things may not need to be "set up", but if you have a good turntable and an LP collection, and you want everything to last, it is important that the turntable be properly dealt with before you plop the discs on the platter.

There are several things to do in setting up the turntable: (1) Tracking Force (TF); (2) Vertical Tracking Angle (VTA); (3) Azimuth; and (4) Anti-skate Control (ASC). Let's go through them one by one.

The Tracking Force (TF) is the amount of weight, in grams, that holds the stylus in the LP groove. A typical TF would be 2.5 grams. The adjustment is made by moving a counterweight at the rear end of the tonearm forward or backward. Here is a photo of the counterweight on the McIntosh MT10. You loosen the knurled knob on top, slide the weight forward or backward, then retighten the knob. The TF should be adjusted before the others, as this insures that you are not putting too much weight on the stylus at any time.

Of course, you need a way of determining what the TF is while adjusting the counterweight. There are several products out there for this. The least expensive ones let you put the stylus on one end of a small strip, with a pivot in the middle, and tiny weights on the other end. When the weights balance the cartridge, you have your measurement. The other kind is the digital balance, which is what I am using here ($129). You turn on the unit (powered by a small battery), press the "Tare" button which sets the balance to zero. Then you carefully set the stylus on the "pan". Here is a photo. In this case, the TF was 2.7 grams, and I needed it to be 2.5 grams. So, I moved the counterweight on the tonearm just a bit to the rear, and it came out to 2.518 grams (second photo).

The Vertical Tracking Angle (VTA) is the angle of tilt, nose down or nose up, that the cartridge has when the stylus is in the record groove. Here are a couple of photos. In the first one, see how the space between the tonearm and the LP is the same from front to back. In the second photo, you can see that the bottom of the cartridge is horizontal to the LP surface.

Adjusting the tracking angle to be horizontal is where you start, and it is accomplished by making sure that the cartridge is mounted flat across the bottom of the head shell and then adjusting the tonearm height so that when the stylus is in the groove, the cartridge and tonearm are horizontal. Once everything is set up and you are playing LPs, you can go back and fine tune the VTA, knowing that adjusting the VTA so that the cartridge is nose down will increase the high frequencies and decrease the low frequencies, while adjusting the cartridge nose up will reduce the high frequencies and increase the low frequencies.

The Azimuth is the angle between a line drawn from the center hole of the LP to the outside edge, and a line drawn through the cantilever as the stylus is in the groove. What you want is for the cantilever to be perpendicular to the line from the hole to the outside edge. The adjustment is made by loosening the screw that holds the head shell on the arm, shown in the photo below, and then turning the head shell until the cantilever lines up with the record grooves. Then you tighten the screw. Because the cartridge moves in an arc, the best that can be done is to have it exactly line up in two points across that arc. The rest of the time, it will be just a bit off. The reason this is important is that with the right channel on the outside edge of the groove and the left channel on the inside edge, if the cantilever is not perpendicular, the stylus will bleed information between the channels. Increased distortion also results. The second photo shows a close-up, and you should notice all the dust on the LP surface. I will talk about how to get rid of this in a later chapter.

The Anti-skate Control (ASC) is used to counteract the tendency for the stylus to be pulled towards the center of the LP as the music is playing. This results from the fact that the groove is one big inward spiral, and the stylus "seeks" the inward grooves because they have lower linear velocity. Because the stylus is being pulled, the force against one side of the groove is greater than the other side. The anti-skate adjustment fixes this. Here is a photo of the ASC on the McIntosh MT10. It is the small thread attached to the pulleys with the round weight at the end. As the tonearm becomes longer (there are 9", 11", and 12" tonearms), anti-skate becomes less important. Also, note that there are forces (other than anti-skate) acting to pull the arm towards the center - particularly if the tonearm is "S" shaped, and forces pulling it towards the outside edge of the LP. The inward force is larger than the outward force, so anti-skate is a force applied to bring the tonearm back towards the outside edge of the disc.