Gemini Red/Black
Gemini is the first mid/side processor in 120V technology. When mastering the sum signal, M/S processing is often the best way to gain targeted access to individual elements of a mix.
M/S ?
Splitting the stereo signal into mid (voice, snare, bass, etc.) and side (guitars, pads, cymbals, etc.) allows them to be processed separately. The mid signal is the sum of the left and right channels of the stereo signal (L+R), i.e. the “in-phase” part of the stereo signal.
The side signal (Side) is the difference between the left and right channels of the stereo signal (L-R), i.e. the “out-of-phase” part of the stereo signal. Gemini can also be used to enlarge or reduce the stereo image. An elliptical filter for shifting the low-frequency component from the side to the center is also on board.
The center
Activating the M/S button splits the input signal (L/R stereo) into a center/side signal.
The exact center position can be adjusted with the balance control and the exact level with the trim control. Both functions can be switched on so that they are only in the signal path when in use.
Exclusive monitoring of the mid-range is possible when the solo function is activated. Processors can be looped in to process the mid signal and activated with the insert button.
The side
The side signal (side) also has a solo function and a switchable insert for external processing.
In addition, the elliptical filter can be used to shift the bass frequencies from the side to the center. This improves the pressure and precision of low frequencies. The Stereo Width control changes the level of the side signal, whereby an increase in level widens the stereo image.
These two functions can also be switched on so that they are only in the signal path when in use.
I/Os and inserts
All inputs and outputs, as well as sends and returns, are balanced with Neutrik XLR sockets. Processors can be connected to the inserts for external processing.
The integration of the Gemini into the Hermes Mastering Router is particularly interesting. This makes it possible to create processing chains that combine classic L/R processing with M/S processing.
Gemini & Hermes
The M/S encoder and decoder stages of the Gemini can each be linked to an insert of the Hermes and can be freely positioned within the processing chain.
Processors located in a chain between the M/S encoder and decoder process the center/side signal. These processors can also easily be mono devices.
The 120V technology
120V technology is SPL's reference technology. It is unique in the world of audio because it works with a DC voltage of 120 volts. This corresponds to four times the operating voltage of IC-based semiconductor operational amplifiers.
The highest possible audio quality requires the highest possible audio operating voltage.
The 120V technology works with +/-60 V. To be able to handle such a high voltage, we have developed special proprietary operational amplifiers that can work with a DC voltage of +/-60 V - the SPL 120V SUPRA operational amplifiers. This high voltage would destroy conventional components and operational amplifiers.
The 120V technology achieves exceptional technical specifications and sonic advantages. Technically, in terms of dynamic range, signal-to-noise ratio and clipping resistance. In terms of sound, in terms of richness of detail and an absolutely relaxed listening experience.
Incidentally, the “120V” in the name of the technology has nothing to do with the local mains voltage from the socket. It refers to the operating voltage in the device with which the audio signals are processed.
The mains voltage from the socket is transformed to the required secondary voltage in the device's internal linear power supply unit with toroidal Transformer. Rectifiers convert this AC voltage into the DC voltages required in the audio device.
Technical data
Analog inputs and outputs; XLR (balanced)
- Maximum input and output level: 32.5 dBu
- Input impedance: 20 kΩ
- Output impedance: 75 Ω
- Common mode rejection: -79 dBu
- Frequency response (-3dB): 10 Hz to 150 kHz
- Crosstalk (1 kHz): -108 dBu
- THD + N (+20 dBu): -110 dBu
- Noise (A-weighted, all stages & filters active): -98.2 dBu
- Dynamic range: 135 dB
Internal power supply; linear power supply with shielded toroidal Transformer
- Operating voltage for analog audio electronics: +/- 60 V
- Operating voltage for relays and LEDs: + 12 V
Power supply unit
- Mains voltage (selectable, see fuse chamber): 230 V AC / 50; 115 V AC / 60 Hz
- Fuse for 230 V: T 500 mA
- Fuse for 115 V: T 1 A
- Power consumption: max. 40 VA
Dimensions & weight
- W x H x D (width x height x depth): 482 x 44 x 300 mm
- Weight of the device: 5 kg
- Shipping weight (incl. packaging): 6.8 kg