owner's manual contents | 01 10/03 02 04 05 09 15 17 19 20 21 controls introduction technology set up operation protection system running in and warming up care and maintenance technical data 02 | controls controls | 03 The 700:7r is designed for the simplest possible operation, and the only controls are two mode switches on the rear panel. One sets the standby mode and the other the channel bridging. Details of these are given on pages 11 and 15. S pe cifi cat io n shown ma y va r y for dif fere nt countr ie s 04 | introduction 5, 6 or 7 speaker system? All are catered for by the 700:7r. The 700:7r is a high-performance sevenchannel amplifier that delivers sound reproduction of outstanding clarity and purity together with the flexibility to handle a wide range of home theatre applications. The 700:7r provides seven channels of 100W into 8 Ohm (7.1 set-up), or can be instantly switched to give five channels of 100W and one channel of 150W (6.1 set-up), or three channels of 100W and two channels of 150W (5.1 set-up). For details see page 11. The seven channels could be assigned as: Channel Rear panel text Power Left LEFT 100 W Right RIGHT 100 W Centre CENTRE 100 W Surround Left Surround Right SL 100 W SR 100 W Back Left BL 100 W Back Right BR 100 W The amplifier switches itself to a standby mode when not in use, to minimise power consumption. It returns from standby to active on receiving a signal input or external contact closure; alternatively it can be set to stay permanently in the active mode. For details see page 15. The 700:7r includes comprehensive but completely unobtrusive protection against overload, excessively prolonged clipping, DC offsets, and high temperatures. t e c h n o l o gy | 05 An Optimal Mix of Global and Local Negative Feedback The 700:7r gives excellent linearity and low distortion without relying on excessive global negative feedback, which can present difficulties with stability and the handling of rapidlychanging signals. The 700:7r design is implemented by giving each amplifying stage controlled amounts of local feedback, which not only linearises it but also defines the gain and other vital parameters closely. Each stage is thus configured for dependable and predictable operation, so that when they are joined together to build a complete amplifier, and a carefully chosen amount of negative feedback applied around it, the results are highly dependable and predictable. Cascode Compensation The 700:7r uses an advanced loop stabilisation concept called Cascode Compensation. To the best of our knowledge TAG McLaren Audio is the only manufacturer to use this sophisticated and elegant system in an audio amplifier. Its advantages are as follows: Excellent stability. All the active components involved are operated under circuit conditions that maximise their bandwidth. This results in greater stability when the negativefeedback loops are closed. Inherently good supply-rail rejection. Components that are essential for powersupply filtering in a conventional amplifier are no longer required, saving weight and cost and enhancing reliability. Reduction of DC drift. In a normal highpower amplifier transistors in sensitive parts of the circuitry get warm, which means their characteristics vary depending on the air flow around them. Variations in cooling can appear as DC drift at the output. Cascode compensation transfers the heat dissipation to noncritical parts of the circuit and DC drift is virtually eliminated. 06 | t e c h n o l o gy The Output Devices The output devices are bipolar junction transistors chosen for maximum linearity in terms of sustained current gain at high collector currents. The advanced MT-200 package is used which gives a greater area for heat transfer than the traditional TO3. This reduces junction temperatures and further enhances reliability. Exceptional Quiescent Stability It is universally accepted that accurate setting and stability of quiescent conditions is crucial to optimal Class-B operation. The bias range over which the best linearity is obtained is narrow, and on either side of it crossover distortion increases markedly. This consists of highorder harmonics that are acknowledged by all as undesirable; it is therefore of the first importance that an amplifier stays in its optimal bias range, despite the many varying conditions it will face in operation. The 700:7r has extremely accurate quiescent control. Quiescent conditions are stabilised against: Output level and load impedance changes This is implemented by a unique sensing configuration that gives much faster and more accurate assessment of output device junction temperatures than the conventional methods. Mains voltage changes It is not widely known that changes in mains voltage can affect amplifier quiescent conditions even if all of the small-signal and biasing circuitry is made immune to these variations. The effect is subtle and complex, but is dealt with authoritatively by circuitry unique to TAG McLaren Audio. t e c h n o l o gy C o m p rehensive pr o t e c t i o n The 700:7r has sophisticated and dependable protection for both its own circuitry and connected loudspeakers. An instantaneous overload protection system monitors the current and voltage conditions in the output devices and limits power dissipation in critical circumstances. If the excessive loading persists, an intelligent long-term protection algorithm disconnects the load to prevent excessive thermal stress which can shorten component life. | 07 Sophisticated muting The 700:7r has a sophisticated muting system, which stops you hearing loud, annoying switching noises and protects both the amplifier and the loudspeakers. Particular care has been taken to make sure that the muting circuitry, when switched off, doesn't affect the sound quality. For this purpose carefully selected relays with minimal crosstalk between coil and contacts have been used. Low distor t i o n A theoretically ideal amplifier reproduces sound perfectly over an infinite range of frequencies - starting from well below the audible range and extending far above the capabilities of human hearing. Although sound outside the human hearing range of approximately 20 Hz to 20 kHz cannot be heard, it can significantly distort the quality of music reproduction through an effect which audio engineers call `intermodulation distortion'. This type of distortion moves imperfections that originate outside the hearing range back into the audible frequencies. To minimise this effect, TAG McLaren Audio amplifiers have a frequency response which extends both above and below the range of normal human hearing. 08 | t e c h n o l o gy mixed technology construction With surface mount components for fast digital signal transfer and leaded throughhole components for perfect audio signals, the 700:7r incorporates mixed technology construction to optimise performance. The result is uncompromised sound in a small size. Straight line technology An amplifier must respond to very low frequencies but block any Direct Current (DC) to prevent intermodulation distortion. This is traditionally achieved using capacitors, which also block some of the low-frequency signals. In the 700:7r a feedback circuit eliminates DC offset voltage and allows the signal path to be direct coupled without any capacitors, an arrangement called `straight line' technology. The result is a very precise reproduction of the lowest bass. Supersonic frequency r e s p o n s e In order to reproduce high frequencies, the 700:7r is constructed using highly-rated, high-precision components. The circuit has been painstakingly designed to minimise audio signals picking up interference and intermodulating. Exceptional transparency and purity of sound are the result. set-up p re p a r a t i o n | 09 We know you are keen to get your 700:7r working. This section will have you listening as quickly as possible. The controls diagrams located on pages 2 and 3 of this manual will help you find your way around your 700:7r(1). safety first To prevent the risk of electric shock follow these instructions carefully. If in doubt consult a qualified electrician · Please ensure that there is adequate ventilation above and below the unit. · The ventilation of the 700:7r should not be impeded by covering the ventilation slots with items such as newspapers, table cloths, curtains etc. · Place the 700:7r on an open flat surface. · Do not use in a cabinet or on a soft surface such as a carpet. · Do not place any other piece of equipment on top of the 700:7r. · Do not place naked flame sources such as lighted candles on the 700:7r. · Do not expose the 700:7r to dripping or splashing liquids. · Do not place objects filled with liquids, such as vases, on or near the 700:7r. b e f o r e you start Make sure that all the components of your system are disconnected from the AC supply whenever you change any connection. positioning The 700:7r is capable of consuming approx. 2000 Watts of electrical power during demanding presentations. This results in significant heat being dissipated. Make sure there is adequate ventilation for the amplifier. It is important that the cooling slots in the top and bottom are not obstructed, and there is sufficient space around the unit to allow for the free circulation of air. Avoid operating the amplifier on a soft surface, such as thick carpet, which is likely to block the slots underneath, 1 . Throughout this manual, b o l d print indicates the lettering that you will find on the re ar panel of your 700:7r 10 | set-up remove power Before making any signal connections ensure the amplifier is not connected to the mains supply. signal connection Ensure that the amplifier mains plug has been removed from the wall socket before making loudspeaker connections. Connect your pre amplifier/av processor using good quality analog interconnects. loudspeaker connection Ensure that the amplifier mains plug has been removed from the wall socket before making loudspeaker connections. When making the connection, ensure that the spade terminal is correctly located and the loudspeaker terminal is fully tightened. set-up 7channel set-up For seven channel use the channel bridging switch is in the `off' position. | 11 You will find 7 pairs of loudspeaker terminals on the rear of the unit. For seven channel use, the speakers are connected between the + (red) and -(black) terminals as shown above. Connect the red (+) terminal of the loudspeaker to the red terminal on the rear panel of the 700:7r. In turn connect the black (­) terminal of the loudspeaker to the black terminal on the 700:7r. It is not advisable to change the position of this switch when the amplifier is powered and connected to loudspeakers. No damage to the amplif ier will r esult, but you may apply an unexpectedly high level to the loudspeakers. 12 | set-up Bridging When the 700:7r is operated in bridged mode, two amplifier channels are used to drive each loudspeaker, for greater power output. To use bridged modes of operation you must alter the position of the channel bridging slide switch on the rear of the unit. This has three positions and allows you to bridge just BR and SR to give one extra-powerful channel, or bridge both BR-SR and BL-SL to give two extrapowerful channels. The operation of the LEFT, RIGHT and CENTRE channels is not affected. 6 channel set-up The channel bridging switch is put in the middle position marked "BR+SR" When the BR and SR amplifiers are bridged, the + lead of the speaker cable connects to the BR+ output terminal, and the - lead of the speaker cable connects to the SR+ output terminal as shown. To apply signal to the BR-SR bridged channel use the upper RCA input (marked "In A"). The lower RCA (SR in) is not used. It is not advisable to change the position of this switch when the amplifier is powered and connected to loudspeakers. No damage to the amplif ier will result, but you may apply an unexpectedly high level to the loudspe akers. set-up 5 channel set-up The channel bridging switch is put in the right position marked "BR+SR BL+SL" The BL and SL amplifiers are now also bridged, and the + lead of the speaker cable connects to the BL+ output terminal, and the - lead of the speaker cable connects to the SL+ output terminal, as shown. To apply signal to the BL-SL bridged channel use the upper RCA input (marked "In B"). The lower RCA (SL in) is not used. To apply signal to the BR-SR bridged channel use the upper RCA input (marked "In A"). The lower RCA (SR in) is not used. | 13 It is not advisable to change the position of this switch when the amplifier is powe red and connected to loudspeakers. No damage to t he amplifier will result, but you may apply an unexpectedly high level to the loudspeakers. 14 | set-up av processor or preamplifier connection Before making signal connections make sure the av processor/pream ...