HLabs Audio EQ169+ is a mono mastering equaliser in a 1U chassis, based on the Studer 169 circuit topology and extended with a high-pass filter, three gain-range modes and output level trim. Every knob sits on a stepped switch.
A setting you can reproduce, including across a pair
A mastering EQ without stepped controls is not usable in stereo: two units set by eye are never identical, and half a decibel of difference in one band shifts the image. The EQ169+ puts an eleven-position switch behind every knob, and gain matching between units is ±0.1 dB. A setting can be recalled a week later, on a different session, and on the second unit of a pair.
Three gain modes instead of three different equalisers
The same circuit faces different demands when tracking, on a bus and in mastering. Standard mode gives ±12 dB on the Presence band and ±15 dB on the shelves; Hybrid mode limits the shelves to ±5 dB; Mastering mode brings everything to ±5 dB — the resolution at which one click of the knob is an actual decision rather than a leap across half the band. The high-pass filter uses a low-resonance design with ten tuned frequencies from 12 to 160 Hz plus a bypass position.
KEY FEATURES
- Mono mastering equaliser in a 1U chassis
- Topology based on the Studer 169 console circuit
- All controls on eleven-position stepped switches
- Three gain-range modes: Standard, Hybrid and Mastering
- Low-resonance high-pass filter, 10 frequencies plus bypass
- High shelf switchable between 20 kHz and 35 kHz
- Two Presence filters, 22 frequencies in total from 150 to 7000 Hz
- Low shelf switchable between 20 Hz and 60 Hz
- Output gain trim of ±3 dB in 0.5 dB steps
- Transformerless input and output, relay-operated bypass
- Gain matching between units of ±0.1 dB
TECHNICAL SPECIFICATIONS
- High-pass filter: 12; 16.4; 20.6; 25.0; 30.9; 42; 55; 78; 110; 160 Hz plus bypass
- High shelf: 20 kHz or 35 kHz
- Presence filters: 22 values from 150 to 7000 Hz, Q ≈ 1.0
- Low shelf: 20 Hz or 60 Hz
- Standard mode: ±12 dB on Presence, ±15 dB on shelves
- Hybrid mode: ±12 dB on Presence, ±5 dB on shelves
- Mastering mode: ±5 dB on Presence and on shelves
- Maximum input and output level: +22 dBu
- Input impedance: 48 kΩ; output impedance: 50 Ω
- THD: 0.005% at 0 dBu, S/N above 108 dB
- Frequency response (1 kΩ): ±0.1 dB from 5.4 Hz to 25+ kHz
- Chassis: 19-inch rack, 1U
