M-Audio Torq 2.0 [151/171] Power threshold controlling erratic velocity values

Chapter 14: External and MIDI Control

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Torq 2.0 User Guide

Power Threshold (Controlling Erratic Velocity Values)

A turntable is a very sensitive piece of equipment. It can take the smallest vibrations and amplify them into

audible sound. That’s what’s happening when you play a record—the grooves in the record vibrate the stylus

as they play and those vibrations are translated to audio. The problem with turntables, though, is that they

cannot distinguish between what is an intentional vibration caused by the moving grooves in the record and

an unintentional vibration picked up through the body of the turntable. For example, if you kick the table the

turntable is on, that “thump” will be transferred through the turntable up through the needle and translated

into sound.

What this means, in terms of the External Control system, is that vibrations and other unintentional noise

can “contaminate” the control signals being read from the vinyl. When this happens, the noise can tempo-

rarily throw off the ability of Torq to track the records.

In order to help minimize this problem, Torq has a setting called “Power Threshold” with various level set-

tings. The idea is to set this value above any of the extraneous noise such that Torq will only focus on the

louder control signals from the records.

To set the Power Threshold:

1 Open the External Control Preferences and enable External Control.

2 Place the needle of your turntable on the Control Vinyl, but leave the turntable stopped.

3 Lower the Power Threshold to -40 and look at the Velocity value for the deck.

4 If the Velocity is showing random values even though the turntable is stopped, that means the Power

Threshold is too low—Torq is picking up noise and interpreting it as a control signal.

5 Increase the Power Threshold by 5dB and look at the Velocity value again. If you still see random Velocity

values, raise the Power Threshold another 5dB.

6 Eventually, you’ll reach a point where the Velocity stays at 0.00. This is the optimal setting for the Power

Threshold.

Error Index

If you’ve checked your audio cable connections and have also replaced your turntable’s needles yet still expe-

rience problems, go to the External page of the Torq Preferences (see “External Preferences” on page 122), and

look at the Error Index displays. These boxes typically display a number between 0.15 and 1.50, which is per-

fectly normal. If the number is above 2.0, it will turn red, indicating that there is too much noise in the audio

signal for Torq to properly track position and velocity. Try cleaning the record using a high quality vinyl clean-

ing system. Too much dirt on the record can cause errors in the tracking process.

A high Error Index can also be caused by wear and tear on the Control Vinyl. Each time a record is played, it

is slightly damaged, especially if the tracking weight of the needle is very heavy. After repeated use, the control

signal may become distorted and unreadable. Simply flip over the Control Vinyl to the second side or pur-

chase a replacement record from the M-Audio Webstore (www.m-audio.com).

If you’re in a noisy environment that does not have proper turntable isolation (to prevent external vibra-

tions from being picked up by the stylus), you may need to raise the Power Threshold setting a little higher

to filter out the additional noise in the room.