EFFECTS LOOPS – The serial EFFECTS LOOP jacks are provided to allow access to the signal for the purpose of inserting signal processing equipment such as compressors, chorus, delay, and reverb processors. Individual pre- EQ loops are provided for the TUBE channel and the FET channel. An additional MASTER post EQ loop is provided for the summed (TUBE + FET) signal. This loop may also be used as a PREAMP OUTPUT or POWER AMP INPUT patch point. SEND (output) and RETURN (input) are nominal +4 dB level.
“Series” devices (such as compressors and gates) require that the signal flow out from the SEND jack on the amplifier, through the processing device, and back into the RETURN jack on the amplifier. Parallel or mixed signal devices (such as chorus, delay and reverb processors) require that the signal flow out of the SEND jack on the amplifier,
and into the processing device where it is split into a dry (unaltered) signal and a wet (processed) signal. On the processing unit, you will use the mixed signal output to return the signals (both wet and dry) to the RETURN jack on the amplifier. The ratio between the wet signal and the dry signal is heard as the amount of effects added back to the original signal, which is controlled by the mix knob (also called “balance”) on the effects processor. This may be a real knob (as in the Alesis® Microverb), or software controlled (as in the Yamaha SPX-90, SPX900 or SPX 990). Set the input sensitivity on the effects processor according to the manufacturer’s instructions. The front panel MUTE switch will also mute all of the SEND outputs when engaged.
FOOT SWITCHES – A DIN connector is provided for connecting the included 5-button footswitch. Model# F/S-STL-MAX. This footswitch controls channel switching and mixing along with all the global SIGNAL SHAPE circuits. Additionally a ¼” footswitch jack is also provided for switching the MUTE function separately. Any single button latching style footswitch will operate this function.
HEADPHONE OUT – A 1/4” TRS jack is provided for connection to headphones for silent practice use. A speaker load is not required. Do not connect this output to anything but headphones.
POWER AMPLIFIER – The SHUTTLE®MAX 12.2 uses 2 state-of-the-art, Class D power amplifiers with high frequency Switch Mode Power Supplies (SMPS) to achieve unprecedented high performance and light weight packaging. Switch Mode Power Supplies convert the AC line directly to high voltage DC then the precision PWM (pulse width modulation) inverter creates a new AC power signal at a frequency more than 1000 times higher than the original wall frequency of 50/60Hz. This new high voltage, high frequency power signal is then fed into a custom high frequency transformer that steps the voltage down, a high frequency rectifier and high ESR filter capacitors finish the process off by converting the high frequency AC signal back to the DC voltages that the amplifier’s internal circuitry uses. One advantage of this conversion process is that the DC power supply rails are refreshed more than 1000 times more often than in traditional linear supplies, thus reducing annoying hum in the audio signal. The high frequency switching is used to reduce the size and weight of the magnetic and filter components while increasing the performance by recharging the power supply rails more often. The Class D amplifier uses digital PWM techniques similar to those in more familiar digital to analog converters to reduce the size and weight by a factor of 10 times that of a comparably rated conventional Class AB amplifier. Essentially, a Class D amplifier converts the analog signal into a logic level PWM digital signal with a digital to analog converter, level shifts this PWM signal up to a higher voltage and current and then reconstructs the analog signal by passing it through what is essentially a power digital to analog converter. Additionally, we developed our proprietary 3DPM™ technology to give a distinctly analog feel and sound to the class D platform. This system provides exceptional performance even for low frequency applications such as bass guitar.
SPEAKER OUTPUTS – The SHUTTLE®MAX 12.2 utilizes dual power amp modules (Amp A and Amp B) each with its own Neutrik Speakon™ connector (wired 1+/1-). The minimum speaker load per power amp is 4 ohms. Do not ground either the “+” or the “-” outputs.
The SHUTTLE®MAX12.2 dual power amp design offers a variety of available output power choices: One 8 ohm load (either Amp A or Amp B driven) . . . . . . . 375 watts
One 4 ohm load (either Amp A or Amp B driven) . . . . . . . 600 watts Two 8 ohm loads (Amp A and Amp B driven) . . . . . . . . . . 750 watts One 4 ohm load (Amp A) and one 8 ohm load (Amp B) . . 975 watts Two 4 ohm loads (Amp A and Amp B driven) . . . . . . . . . . 1200 watts
