TerraTec PHASE 26 USB, Руководство пользователя

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the record. The signal from the pickup must therefore be processed (filtered) before it can
be used.
The Recording Industry Association of America (RIAA) has defined a standard for the
changes to the frequency ranges to ensure that all records can be played using the same
filtering. The quality of the equalization process is thus an important factor in the overall
quality of a phono preamplifier.
Shielding.
Due to the relatively low output levels that even moving-magnet systems achieve (MM
approx. 2-5 mV, MC approx. 0.1-0.4 mV), a certain amount of protection has to be
provided against external sources of noise. For example, using an overly simple power
supply design can result in unpleasant AC hum.
Unfortunately, the mounting number of electronic devices in an average household
means an increasing amount of electromagnetic interference. While these waves are very
weak, they can still interfere with the signal from the pickup, which is also very weak, as
mentioned above. This problem can be dealt with by carefully shielding the amplifier, as is
the case with the PHASE 26 USB system.
The ground wire of your turntable, if present, also fits in with this topic. This wire estab-
lishes an electrical connection between the turntable and the shielding to help prevent AC
hum.
Recording...
To take full advantage of the dynamic scope of the input converter, it is important that you
configure the output level of the phonoPreAmp correctly. Play the record you want to
record and watch the peak LED in your recording software while doing so. Find the
adjustment level at which the signal is not clipped (also called overmodulation). The
optimal level is just below the 0 dB limit. Unlike recordings that you may have made in the
past with a tape deck, digital recordings must never exceed the maximum level. In the
analog world this might have passed for a desirable “tape saturation” effect, but with
digital recording technology it leads to clearly audible distortion, which is virtually impossi-
ble to “repair”.
If your audio software lets you adjust the sampling frequency and bit resolution, select 24
bit and 88.2 kHz (that's the 24/96 mode on the PHASE 26 USB, for recording only), so
that the downstream RIAA filter (VST plug-in) can operate at peak performance. Later,
your audio software will have to convert the data to standard CD quality of 44.1 kHz and
16 bit. You will want to use 88.2 kHz because it converts to 44.1 kHz significantly better.
The recording's finished: now what?
Now that you've made the recording with your sound card and a suitable program such as
WaveLab Lite, you will probably want to edit them at the digital level. “Sound Laundry
TerraTec Edition” is included in the software package of the sound card. It's a powerful
42 PHASE 26 USB (English)