PQ Black/Silver
This is a unique equalizer - for several reasons. It has two sets of five fully parametric filter bands, each of which can be switched between constant-Q and proportional-Q! And there is endless headroom and a very special kind of EQ sound - thanks to 120V technology.
The filter bands
Detented potentiometers
Recall of all settings is easy to realize thanks to the potentiometers with 41 detents.
Cut/Boost & 1/4 Gain
Each filter band can be cut or boosted by up to 20 dB. If only minimal intervention in the music material is required, the 1/4 gain switch can be used to reduce the boost or cut from +/-20 dB to +/-5 dB.
Frequencies
We have designed the frequency distribution to overlap widely between the bands so that problematic frequencies can also be tackled with two bands.
- LF: 10 Hz - 330 Hz
- LMF: 33 Hz - 1 kHz
- MF: 128 Hz - 4.1 kHz
- MHF: 310 Hz - 10.2 kHz
- HF: 760 Hz - 24 kHz
Bandwidth Q
The bandwidth Q determines the steepness of the filter or its bell characteristic. A low Q is a wide bandwidth and a high Q is a narrow bandwidth. The labeling of the scaling is divided into two parts. The values highlighted in white refer to the proportional Q mode and the values not highlighted refer to the constant Q mode.
On/Off
The orange button is used to switch the band on and off.
Constant & Proportional Q
The blue button is used to switch the Q mode. In constant Q mode, the amplitude remains constant regardless of the selected bandwidth. This is ideal for eliminating interference frequencies).
In Proportional Q mode, the amplitude is proportional to the bandwidth. It decreases with increasing bandwidth and vice versa. At the smallest bandwidth setting, the maximum amplitude value is +/- 20 dB, while the maximum amplitude drops to +/- 2.8 dB at the largest bandwidth setting. This control behavior simplifies sensitive, creative processing and is very useful musically, as high amplitudes become increasingly unusable as the bandwidth increases.
The center section
Auto Bypass
For an objective assessment of the processed music program, it makes sense not to switch between the original signal and the processed signal yourself, but to leave this to an automatic system.
It is also an advantage that you do not have to move out of the stereo center for an optimal assessment of the processing and can concentrate fully on the program. The switching time window can be determined using the Interval control. Turning it clockwise extends the time interval.
Link
The PQ is designed as a completely separate dual-mono, two-channel equalizer and can process two mono music programs individually at the same time. It is of course also possible to edit a stereo program (left/right). If the link function is activated, the LF, LMF, MF, MHF, HF On/Off and Con. Q/Prop.Q on both sides are switched together by the buttons on one side. This makes it possible to activate or deactivate a filter band or the Q characteristic on both sides of the equalizer by pressing a button.
By default, the right side controls the left side in link mode. However, this can be adjusted to suit individual working habits. If the channel switch of a channel is pressed until it flashes, this channel controls the other side from this point on.
Channel on/off
The entire channel is switched on and off with the orange buttons.
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. In order to handle such a high voltage, SPL has developed special proprietary operational amplifiers that can operate 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), RCA
- Maximum input and output level: 32.5 dBu
- Input impedance: 20 kΩ
- Output impedance: 75 Ω
- Common mode rejection: -82 dBu
- Frequency response (-3dB): 10 Hz - 100 kHz
- THD +N (+30 dBu, 1 kHz): 0.0005 %
- Noise (A-weighted): -94.3 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 3.15 A
- Fuse for 115 V: T 6.3 A
- Power consumption: max. 100 VA
Dimensions & weight
- W x H x D (width x height x depth): 482 x 177 x 300 mm
- Weight of the device: 15.2 kg
- Shipping weight (incl. packaging): 17.8 kg