1. USING THE CL-5000 FOR RECORDING AND CASSETE DUPLICATION
In the recording and duplication field, the goal should always be to achieve an optimum recording level onto the recording
media. Too low or too high recording levels lead to side effects such as noise, distortion, etc. In mastering and multi-track
recording, as well as in duplication, one should always take care to utilize the full dynamic range of the tape recorder, DAT
recorder etc. In principal, it is possible to control the recording level by “riding” faders, which means that the gain is increased
with low-level signals, and reduced for high-level signals. It is obvious that this method is insufficient, especially in live record-
ings, because the expected signal levels cannot be anticipated correctly. Furthermore during multi-track recordings, which are
run under hectic circumstances, the signal level of all channels cannot be monitored and controlled at the same time. Generally,
it is not possible to achieve satisfying recording results using manual control in this way.
An automatic gain control system achieves better and more constant results. Use the CL-5000 by starting with the initial settings,
and use its dynamic control functions to drive either an analog or digital recording noise and distortion free up to the limit of its
maximum dynamic range.
1.1 The CL-5000 In Digital Recording and Sampling
During analog recording, too-low recording levels lead to an increased noise level, whereas too high levels will cause a com-
pressed and “squashed” sound. In extreme cases, loud levels will cause distortion due to tape saturation. In contrast to analog,
side effects in digital recording always become extremely audible: with decreasing levels a tape loses resolution and the record-
ing sounds “hard” and loses “atmosphere”. With excessive level, the recording sounds harsh and heavily distorted. In order to
avoid these effects, the limiter function of the CL-500 should be used. With proper limiting, a digital recording or sampling can
be optimally set to optimum levels without any problem.
1.2 The CL-5000 In Mastering
Mastering is one of the most critical processing steps in recording. During mastering, it is the goal to achieve a “maximum level”
copy of the recording, without any noise or distortion. In many applications it is further required to produce a high average
volume. In the field of commercial media for example, this is apparent especially with records and cassettes processed with high
average volumes. Quite often in these cases, however, dynamics suffer dramatically, because the program material has been
compressed and limited too heavily. Using the combined compressor and limiter functions of the CL-5000 allows you to drasti-
cally increase the overall volume, without audibly affecting the dynamics.
Proceed as follows:
1.
Limit the dynamics of the program material by 6 dB using the limiter function. By softly clipping just the transients, the real
audio signal will not be limited, resulting in a higher headroom. The overall gain can now be increased by 6 dB, which
leads to a higher volume. More that 6 dB should not be limited, otherwise side effects could become audible.
2.
Therefore, in addition, you should also use compression. It is recommended that the compression is limited to the “first” 6
dB of the dynamic range only. A high threshold level in the AUTO mode will generally give good results.
This effect is particularly noticeable with DAT recorders, whose level indicators achieve a response time of less than 1 ms. Set the
DAT recorder at unity and now reduce the THRESHOLD control of the CL-5000 until the GAIN REDUCTION meter indicates a
gain reduction of 6 dB. The “cut” signal peaks cause a reduced recording level of about 6 dB, which is visible on the level
indicators of the DAT recorder. Now increase the recording level of the recorder back to unity. The result is a clearly louder
recording without any loss of sound.
SPECIAL APPLICATIONS
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