1:Mic inputs - Provided in mono channels only. Use these electronically balanced XLR jacks to connect microphones to the TM500. These are intended to accept signal from low-level, low-impedance mics but can also be used for signal from other sources (such as direct injection boxes) if the channel’s Trim control (see #5 below) is turned down. WARNING: Do not connect a channel’s microphone input if you already have something connected to its line input (see #2 below); all channels are designed to accept only one source or the other.
2:Line inputs - Use these electronically balanced 1/4" jacks to connect line-level sources such as synthesizers, drum machines, CD players, tape decks, or effects processors to any of the TM500’s twelve channels. Stereo devices should be connected to the stereo channels (9/10 and 11/12). Use balanced three-conductor cabling and Tip/Ring/Sleeve (TRS) plugs wherever possible (unbalanced two-conductor plugs can also be inserted into these inputs, but you’ll get better signal quality and less outside noise and hum if you use balanced lines). The “Connecting the TM500” section on page 10 in this manual provides more information on how best to use channel inputs. WARNING: Do not connect a channel’s line input if you already have something connected to its microphone input (see #1 above); all channels are designed to accept only one source or the other.
3:Channel Inserts - Provided in mono channels only. Use these to insert an external effects processor (such as outboard equalizer, compressor/limiter or noise gate) into any of the TM500’s mono channels in an “effects loop” configuration. These jacks accept 1/4" TRS plugs, with the ring carrying the send signal and the tip carrying the return signal. Normally, this will be connected to a Y-cord; see the “Connecting The TM500” section on page 10 in this manual for more information and a wiring diagram.
4:Peak LED - This warning light indicates an overload situation. It lights whenever a channel’s signal is 3 dB short of clipping. To stop it from lighting (and to eliminate the accompanying sonic distortion), turn down the channel’s input Trim (see #5 below) or reduce the amount of equalization boost (see #6 below).
5:Trim - Determines the input level of the connected signal. In mono channels, this is a knob which is continuously adjustable from +14 dB to -30 dB (in the case of line-level inputs) or from -6 to -50 dB (in the case of mic-level inputs); the input signal is boosted when the knob is turned clockwise and attenuated when turned counterclockwise. In stereo channels, this is a three-position switch, with settings at +4 dB, -2 dB, and -10 dB. For information on how to properly set this for each channel, see the section on page 14 entitled “Setting The Correct Gain Structure.”
6:Equalizer - These knobs determine the amount of boost or attenuation in each frequency band (up to 15 dB for low and high frequencies, and up to 12 dB for the mid frequency). Mono channels provide 3-band eq, while stereo channels provide 2-band eq. The mid frequency control (centered at 1.8 kHz) utilizes a resonant (“bell”) peaking curve, while the high and low frequency controls (centered at 10 kHz and 100 Hz, respectively) utilize shelving curves. A center detent in each knob (at the “0” position) indicates no boost or attenuation (that is, flat response). As each knob is turned clockwise from the “0” position, the frequency area is boosted; as it is turned counterclockwise from the “0” position, the frequency area is attenuated. For more information on the application of EQ, see the “Using Equalization” section on page 17 in this manual.
7:Auxiliary sends - These knobs allow you to route signal to either or both of the TM500’s two monophonic Auxiliary outputs. These are typically used to create submixes (for example, a headphone cue mix) and to feed signal from single or multiple channels to outboard effects devices. At the “0” (2 o’clock) position, the signal is routed with unity gain (that is, no boost or attenuation). As each knob is turned clockwise from the “0” position,
