Calibrating The Bias Current And Recording Level - Sony TC-K615S Operating Instructions Manual

A
1
a)
2
B
a)
BIAS
3
+
–
4
5
38
BIAS REC LEVEL
– + – +
CALIBRATION
b)
b)
c)
d)
Calibrating the Bias
Current and Recording
Level
There are many different types of cassettes
on the market, each with varying magnetic
properties. Although the ATS (Automatic
Tape Selection) system in your unit sets the
appropriate equalization characteristics and
bias current for each tape type, you may be
able to obtain even better results by doing
the bias current and recording level
calibration function described below.
Fig. A shows the BIAS control and REC
(recording) LEVEL control for calibration.
a) Adjusts the bias current within a range
b) Adjusts the recording level within a
Bias calibration
Choosing the proper bias current for a tape
ensures minimum distortion and flat
frequency response. Lowering the bias
current boosts high-frequency response, but
also results in higher distortion. Raising the
bias, on the other hand, reduces distortion,
but also dampens high-frequency response.
You thus obtain proper bias when the bias
current and high-frequency response are
well balanced.
Fig. B shows the BIAS control and a high-
frequency response balance chart.
a) Bias reduced (high-frequency response
b) Bias increased (high-frequency response
e)
c) Output level in dB
d) Frequency in Hz
e) Bias reduced (–)
f)
f) Bias increased (+)
of about 20 %
range of about 3 dB
boosted)
suppressed)
(Continued on next page.)