Harman Kardon A250 Owners Manual - Page 12
TECHNICAL, EXPLANATION, CONTROLS, Treble, Loudness, Control, Contour, Switch, Balance
View all Harman Kardon A250 manuals
Add to My Manuals
Save this manual to your list of manuals |
Page 12 highlights
The Model A-250 incorporates the following front panel controls. Viewing the instrument from left to right you will note a TREBLE control ( on/off switch is incorporated in this control), BASS control, LOUDNESS control, BALANCE control, MODE switch and FUNCTION switch. On the upper left section of the front panel you will note two SPEAKER SELECTOR switches and a CONTOUR switch. On the right section of the front panel there is a RUMBLE FILTER switch, SCRATCH FILTER switch and an EQUALIZATION switch. TECHNICAL EXPLANATION OF THE CONTROLS Since a stereo amplifier is actually two amplifiers in one, the number of operating controls would normally be doubled. This would make operation unnecessarily cumbersome. For convenience the duplicate controls are mechanically tied together, or ganged, to be operated by one knob. Bass and Treble: The BASS and TREBLE controls on the Model A-250 provide the full range of tonal adjustment necessary for high fidelity listening. These controls can either boost or cut the bass and treble tones of the stereo system. The controls should be set in accordance with your listening preference, speaker characteristics and room acoustics. Loudness Control: This control adjusts the volume level of any program material fed into your stereo system. Its effect can be modified by the CONTOUR switch. Contour Switch: One of the limitations of human hearing is its tendency to lose sensitivity to the very low pitched sounds, as the program sound level is reduced. It is this characteristic (known as the Fletcher-Munson effect) which causes one to play music programs at high listening level in order to experience the full rich tone available from fine modern recordings. The Harman-Kardon CONTOUR switch compensates for the Fletcher-Munson effect thus eliminating high listening levels as a requisite for full enjoyment of reproduced music. For low level listening throw the CONTOUR switch located on the front panel to either number I or number 2 position depending on your listening preference. You will note how the low frequencies become more apparent while th volume level remains unchanged. Balance Control: The nature of stereo reproduction is such that it requires two identical channels to attain the highest degree of faithfulness and spatial distribution. Any variation in the efficiency of one channel as compared to the other will disturb this relationship. Since there may be slight differences between the two speakers, tape heads, etc., the A-250 includes a control to balance one channel against the other. Sufficient range is covered by this control to permit rebalancing of the overall system even in cases where major unbalance exists. This control may be set anywhere within its range to attain system balance. When the BALANCE control is properly set, the apparent sound source will lie in a broad area between the two speakers. When the BALANCE control is rotated to the right the sound will move to the right and when the control is rotated to the left, the sound will move to the left. Mode Switch: The MODE switch selects between stereo operation, where a stereo program source is available, and monaural operation utilizing the full power of both channels and both speakers when the program source is monaural only.