Plinius Audio SA-250 manual

Class A Power Amplifier[...]

2[...]

3 CONGRATULATIONS CONGRATULATIONS CONGRATULATIONS CONGRATULATIONS on your decision to become the proud owner of this Plinius SA-250 Power Amplifier. This manual has been prepared to help you understand the operation of your amplifier, and to provide information about its design and the variety of ways it may be used. We have designed and manufactur[...]

4 Introduction .................................................................................................................. ......................Page 3 Precautions ................................................................................................................... .....................Page 5 Amplifier Features - FRONT PANEL ..[...]

5 Please take special note of the following precautions before operating your new amplifier: • The Plinius SA-250 Power Amplifier can be operated in bridged mode and may deliver in excess of 900 watts into 8 ohms. This amplifier is also capable of a very large peak current delivery. • The Plinius SA-250 Power Amplifier operates in Class A. It i[...]

6 The front of the Plinius SA-250 Power Amplifier incorporates a small panel fitted with three switches. These switches control the functions most used on the amplifier. F RONT P ANEL L AYOUT S HOWING M UTE , M AINS A ND B IAS S WITCHES The operation of these switches is, from the left: MUTE SWITCH It is not recommended practice to interfere with t[...]

7 BIAS SWITCH This switch on the right of the panel alters the operating bias of the amplifier. The switch operates on a pulse system and lights the Bias LED when the amplifier is switched to Class A. In Class AB the LED is off. BIAS AB: BIAS AB: BIAS AB: BIAS AB: This position reduces the bias on the output stage to operate the amplifier in Class [...]

8 This panel incorporates all the terminals for connecting the input signals from your preamplifier, and output to the loudspeakers, and mains supply. A reasonable understanding of this amplifier and a logical approach should ensure that you are listening to this amplifier without any difficulties at all. Please remember that your Plinius SA-250 Po[...]

9 INPUT TERMINALS Input terminals for your Plinius SA-250 Power Amplifier are easily accessible and fitted to the top centre area of the rear panel. A brief summary of connection possibilities is listed below, while a more detailed explanation follows later in this instruction manual. RCA INPUTS LEFT & RIGHT: RCA INPUTS LEFT & RIGHT: RCA IN[...]

10 RCA BRIDGED MONO: RCA BRIDGED MONO: RCA BRIDGED MONO: RCA BRIDGED MONO: This option configures your amplifier to drive one loudspeaker from one unbalanced signal fed to the RIGHT RCA input. The loudspeaker is connected to both channels positive (+) output terminals, giving an available power in this mode four times the rated output of the amplif[...]

11 Please note that in order to achieve STEREO performance in either of the Mono modes, it will be necessary to use two Plinius SA-250 Power Amplifiers - one amplifier each for left and right channels. GROUND LIFT SWITCH This switch is located adjacent to the Mains Input Socket, and allows the signal ground to be disconnected from the chassis. In s[...]

12 PLACEMENT AND VENTILATION Your Plinius SA-250 is designed to operate at a moderately high temperature, even more so when used in Class A. The ideal location is on a rigid stand or floor mounted away from direct contact with any temperature sensitive materials or deep pile carpets. The flow of air around the amplifier should also be kept unimpede[...]

13 R EAR P ANEL S HOWING L OCATION O F I NPUT /O UTPUT T ERMINALS It is important that you connect your loudspeakers (outputs) and preamplifier (inputs) to the Plinius SA- 250 Power Amplifier correctly to ensure the amplifier is not damaged, and sounds it’s best with your system. Now that you have read and familiarised yourself with the connectio[...]

14 RCA STEREO Connect your preamplifier or input signal to the two RCA inputs at the top of the amplifier back panel. Make sure you connect the red coded cable to the red RIGHT RCA input and the black (or white) cable to the black LEFT RCA input. Also make sure the RCA connectors are a snug fit and are inserted all the way in. Next connect your lou[...]

15 Now turn the ACS switch fully clockwise then two positions counter-clockwise so that it is in the XLR Stereo position. It is now safe to switch on your amplifier. XLR BALANCED MONO As with RCA Bridged Mono, this option configures your amplifier to drive one loudspeaker, but from one balanced line input connected to the RIGHT XLR Input. In balanc[...]

16 PHASING (OR POLARITY) It is important to achieve good stereo imaging in your listening room. By observing the wiring instructions above, each Power Amplifier/loudspeaker combination should be in phase. If you experience poor stereo image and/or a lack of bass, check that the loudspeaker wiring has been connected correctly. We recommend that you [...]

17 ERROR DETECTION The Plinius SA-250 Power Amplifier has in-built error detection. This will function under the following conditions: • When the amplifier is overdriven/clipped • If any internal fuse is damaged Should either of these circumstances arise the amplifier will disconnect both channels and mute the input. This condition will remain [...]

18 LED BRIGHTNESS CONTROL Your Plinius SA-250 has an internal LED brightness control that will adjust all three front panel LED’s. A small flat bladed screwdriver can be used to adjust the brightness. The LED brightness control is a small multi turn potentiometer and is located on the front of the main circuit board within the top cavity of the a[...]

19 Your Plinius SA-250 Power Amplifier is designed for use with high fidelity loudspeakers. It should not be used to operate any other type of appliance or equipment. Choice of loudspeakers is one of personal taste, providing the chosen loudspeakers are suitable for use with your amplifier. Be certain that your loudspeakers can handle most of the r[...]

20 Class A has always been regarded as the perfect operating mode for audio amplifiers. Many leading amplifier designers and manufacturers world wide recognise that a well designed Class A circuit has inherently lower distortion than any other design. Class A circuit topology is one in which the total current the amplifier is capable of delivering,[...]

21 250-WATTS RMS PER CHANNEL INTO 8 OHMS. 450-WATTS RMS PER CHANNEL INTO 4 OHMS. BOTH CHANNELS DRIVEN FROM 20Hz TO 20kHz AT 0.05% TOTAL HARMONIC DISTORTION. S B B B B RIDGED RIDGED RIDGED RIDGED O O O O UTPUT UTPUT UTPUT UTPUT : :: : 900 Watts RMS 20Hz to 20kHz into 8 ohms (Mono). S D D D D YNAMIC YNAMIC YNAMIC YNAMIC H H H H EADROOM EADROOM EADROO[...]

22 ACS (Amplifier Configuration Selector) ......................................................................................... .. Page 9 Balanced Signal ................................................................................................................ ...........Page 10 Bias Class A ...............................................[...]

23 All operational, technical and descriptive material published here is subject to change at any time without notice. For further product information or queries, please contact us at the address below. PLINIUS PLINIUS PLINIUS PLINIUS products are designed and manufactured by: Audible Technologies Ltd. Audible Technologies Ltd. Audible Technologies[...]