User manual TASCAM PA-30

[. . . ] 9A09572800 » PA-30 Dual Power Amplifier OWNER'S MANUAL Introduction The TASCAM PA-30 is a high-performance professional audio power amplifier for nearfield studio monitoring and low-level sound reinforcement. In stereo mode, the PA-30 delivers 30 watts per channel continuously into an 8 ohm load - with no more than 0. 05% total harmonic distortion. For applications requiring higher output power, the unit may be operated in BTL (Balanced Transformerless) mode also known as 'bridged' operation - and will deliver a full 60 watts continuously into 8 ohms (see the 'BTL Operation' section of this manual on page 9). In either mode, it exhibits a flat frequency response characteristic from 20 Hz to 20 kllz (+0, ­1dB), with very low residual hum and noise. [. . . ] It has a two-prong, ungrounded AC cord, and may be connected to either two-prong or three-prong outlets. If you have any doubt about the wiring of the outlet that you wish to use, it is wise to test it before making connections. Simple plug-in testers are available from a variety of electronics and hardware stores. Figure 2. Voltage Selector 4 TASCAM PA-30 Features Figure 3. POWER Switch and Indicator A two-position rocker-type switch controls power to the unit. Depressing the upper surface of the switch turns the amplifier on; depressing the lower surface turns it off. The green LED Power indicator will light whenever the unit is on and is connected to a properly functioning source of power. If the Protection indicator lights when the PA-30 is first switched on, turn the Power switch OFF and recheck all of your connections before resetting power. 3. BTL Indicator The orange LED BTL indicator will light whenever the MODE switch (on rear panel) is in the 'BTL (MONO)' position. 2. PROTECTION Indicator The red LED Protection indicator remains off whenever the PA-30 is turned on and is operating normally. If an overload, short circuit, DC offset or other problem triggers the internal electronic protection circuitry, the unit shuts down and the Protection indicator lights. Once the PA-30 is turned off and the fault condition is cleared, the Protection circuit will automatically reset, and normal operation can be resumed (provided that the fault has not damaged the unit). 4. INPUT LEVEL Control A single rotary variable attenuator sets the input sensitivity of the PA-30 Amplifier. The degree of attenuation varies from zero loss (maximum sensitivity) at the 'MAX' position to infinite loss at the 'MIN' position. 5. PHONES Jack This Tip/Ring/Sleeve 1/4" phone jack accommodates 8 ohms or higher impedance stereo headphones. TASCAM PA-30 5 Features Figure 4. INPUTS (A & B, XLR & RCA Type) Two input connectors are provided for each channel: one RCA (phono) jack and one XLR-type female connector. Either connector may be used on a given channel, but both connectors for a single channel should not be used simultaneously. Both inputs present a high impedance, and cause no appreciable loading to source outputs. Input sensitivity is ­10 dBV (0. 3 volt RMS) at the RCA inputs, and +1. 3 dBu (0. 9 volt RMS) at the XLR inputs, for rated output (with Input Level control at maximum). Pin assignments are as follows: XLR-type Pin I = common Pin 2= 'high'(+) Pin 3= 'Iow'(­) RCA-type Shell= common Tip = 'high'(+) If the MODE switch is not correctly set, damage to the loudspeakers or to the PA-30 may result. For a complete explanation of use of the MODE switch, consult the section on 'BTL Operation' on page 9 of this manual. 8. SPEAKERS (A & B) A pair of color-coded locking terminals is provided for output connections to each channel of the PA-30. They will accommodate stripped bare wire, or tinned wine ends. [. . . ] Connecting loads with a lower impedance will result in current limiting, and may trigger the Protection circuits to shut down the amplifier. intentionally out of phase. The single load (remember, BTL is a monophonic, or single-channel, mode) is wired across the two channel output 'hot' (red) terminals, and the black output terminals are left unconnected. The minimum allowable load impedance is 8 ohms (not 4 ohms, as is the case in stereo mode), and the available power to the load is 50 watts continuous (at 8 ohms). BTL mode is electrically identical to push-pull transmission at line level (the signal level is simply much higher): the two channel outputs deliver the same absolute signal voltage, but with opposite polarities. [. . . ]