Omnia Industries Turntable 6FM Manual Do Utilizador
Omnia 6 Use and Installation Guide – Version 1.00a
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Omnia-6fm Connections
Output Connection Options
Tests have shown that post-processing audio power in the low frequency region is so strong that it may
affect the performance of some exciters. It is imperative that your exciter have a dual speed PLL in the
AFC, otherwise it may unlock. If one of your processing goals includes solid, powerful bass on air, this is
an important key point that cannot be overlooked or loudness will be lost due to inefficient modulation.
Output choices are:
Left/Right Analog: This option is provided for compatibility only, and is the least-recommended choice.
The DSP based digital stereo generator included in your Omnia-6fm provides superior performance,
and should be used instead of the one provided in the exciter.
and should be used instead of the one provided in the exciter.
Analog Composite: If you don’t object to your airchain being partially analog, this option will provide
excellent peak control and sound quality. Be sure to use good quality low capacitance coaxial cables
for best performance. Typical cables may be RG-58 or RG-62 type.
for best performance. Typical cables may be RG-58 or RG-62 type.
AES/EBU: The selectable sampling rates in the Output Menu are provided to minimize overshoots caused
by downsampling in external equipment. This option, however, cannot make up for potential sonic
degradations (see “Interfacing with a Digital STL and/or Exciter” below).
by downsampling in external equipment. This option, however, cannot make up for potential sonic
degradations (see “Interfacing with a Digital STL and/or Exciter” below).
The typical connection to a digital STL or exciter is through the standard, balanced AES/EBU connection.
Using a shielded 110 ohm digital audio cable with appropriate XLR connectors on each end, connect the
processor to the exciter. Cable length should be as short as possible, and may not exceed 100 meters (328
feet). The exciter input should be set for flat input, which means that the exciter is not adding any pre-
emphasis to the input signal. In the Omnia-6fm Input menu set the Pre-emphasis "ON" at the correct value
for your country. In the Output Menu, set the De-emphasis option to Off. This ensures that output from the
processor is now pre-emphasized according to the standard in use in your country. You will also need to
adjust the output levels and Output Sampling Rate in the Output Menu. Since the digital exciter will be
providing the stereo generator function, you must set the Peak Output Levels in the Output Menu for the
proper AES/EBU discrete left/right channel levels, and also set the Output Sample Rate to the actual
internal operating sample rate of the exciter.
Using a shielded 110 ohm digital audio cable with appropriate XLR connectors on each end, connect the
processor to the exciter. Cable length should be as short as possible, and may not exceed 100 meters (328
feet). The exciter input should be set for flat input, which means that the exciter is not adding any pre-
emphasis to the input signal. In the Omnia-6fm Input menu set the Pre-emphasis "ON" at the correct value
for your country. In the Output Menu, set the De-emphasis option to Off. This ensures that output from the
processor is now pre-emphasized according to the standard in use in your country. You will also need to
adjust the output levels and Output Sampling Rate in the Output Menu. Since the digital exciter will be
providing the stereo generator function, you must set the Peak Output Levels in the Output Menu for the
proper AES/EBU discrete left/right channel levels, and also set the Output Sample Rate to the actual
internal operating sample rate of the exciter.
Interfacing With A Digital STL and / or Exciter
At the time of this writing, many engineers are proponents of the all-digital broadcast transmission path.
However, there are some key issues which must be dealt with when implementing all-digital transmission
in order to preserve loudness without sacrificing audio quality. One issue concerns the sampling rate of the
audio processor and that of the exciter. In order for two differently sampled systems to be interfaced in the
digital domain, a neat little device known as the “sample rate converter" is used.
However, there are some key issues which must be dealt with when implementing all-digital transmission
in order to preserve loudness without sacrificing audio quality. One issue concerns the sampling rate of the
audio processor and that of the exciter. In order for two differently sampled systems to be interfaced in the
digital domain, a neat little device known as the “sample rate converter" is used.
For instance, a device which outputs digital audio data using a 48 kHz (or higher) sampling rate can be
converted down to a lower rate of, say, 32 kHz. Unfortunately, unless spectrum is limited to the Nyquist
frequency of the lower rate, overshoots can be created, which rob loudness. Detailed information can be
found in the technical papers “Critical issues and Considerations for an All Digital Transmission Path,”
“Digital Dynamics Processing: It’s All In The ’Samples!’” and “Digital Broadcast Audio Processing:
converted down to a lower rate of, say, 32 kHz. Unfortunately, unless spectrum is limited to the Nyquist
frequency of the lower rate, overshoots can be created, which rob loudness. Detailed information can be
found in the technical papers “Critical issues and Considerations for an All Digital Transmission Path,”
“Digital Dynamics Processing: It’s All In The ’Samples!’” and “Digital Broadcast Audio Processing: