User manual TANNOY PROFILE 636

[. . . ] The Stirling SE offers high frequency energy tailoring through a high current gold-plated switch block. Silver plated copper Van den Hul wiring is used throughout, together with specially selected high quality crossover components. The specially designed twin-roll impregnated fabric surround used on the drive unit's cone, ensures midrange purity combined with tight, controlled bass. Tannoy - A Short History In the early days of broadcasting radio sets needed both low and high voltage DC power that had to be supplied by batteries. The lead acid batteries used in the radio sets of the time needed regular recharging. [. . . ] The range of electrical currents passing down the cable from the amplifier to the loudspeaker is very wide. Modern loudspeakers are capable of resolving a dynamic range of at least 80dB with a suitable power amplifier. An 80dB dynamic range corresponds to voltages of between 50 Volt and 0. 005 Volt at the loudspeaker terminals or equivalent currents of between 0. 0006 and 6 Amp. This is a truly wide range of electrical signals to pass down one cable without some interactions causing a loss of resolution in the very small signals. When electricity passes down a wire or cable, what does in at one end is unfortunately different from what comes out at the other. The degree of loss or modification of a signal depends on the physical characteristics of the cable and the nature of the signal. Heavy electrical currents flowing down thin conductors cause heating effects. Very high frequency signals passing along conductors or cables of certain lengths cause electromagnetic radiation effects (aerials). Electrical cables are selected for minimum loss and maximum information resolution considering the type of electrical signals they are designed to carry. A good solution to the problem is to 'bi-wire' the loudspeakers to the amplifier. This means providing two separate sets of cables from the power amplifier to each loudspeaker and dividing the electrical signals into high current, 'slow' signals and light current, 'fast' signals. To replace the grille engage the top of the grille into the slot in the cabinet and push the grill into the recess. Apply slight pressure to the bottom whilst turning the key clockwise to engage the lock. Loudspeaker System Adjustment Each loudspeaker is fitted with a treble energy control located on the baffle beneath the detachable front grille. This high current switch block control can be used to compensate for the varied acoustic characteristics of listening rooms. The control should be adjusted with the amplifier tone controls set to the 'flat' or uncompensated position. This is most easily done by rotating the amplifier balance control to select first one loudspeaker and then the other. It allows the output of the high frequency compression drive unit to be increased or decreased from the linear or 'flat' position over a frequency band from approximately 2kHz to 20kHz. The control has a shelving effect over the 2kHz to 20kHz frequency band. The flattest most linear response from the loudspeaker willl be obtained with both controls set at the LEVEL position, and this position should be used for initial listening tests. If the overall high frequency sound quality seems too prominent the -1. 5 or -3 positions for the energy control should be tried. If the sound appears subdued in the treble region +1. 5 or +3 settings may be preferred. Remember the changes that can be made by moving either control from one position to another are subtle. [. . . ] The loudspeaker system exhibits a time delay response that is in essence independent of reproduced frequencies. In addition, the amplitude (or intensity) response is linear, smooth and consistent. This provides the correct intensity information to recreate the original sound stage. Care of the Cabinet The cabinet is constructed from carefully selected solid walnut and walnut veneers that have been hand waxed before dispatch from our finishing workshop. To maintain the natural wood appearance it is important that only a wax of similar formulation is used. [. . . ]