SPL Qure Premium 9738-P
Equalizer with Lundahl Transformers
The Qure is a two-channel, fully parametric three-band EQ for creative sound design of individual instruments and voices, as well as more complex music signals and mastering. It combines the circuit technology of different eras and also offers new, innovative filter circuit solutions for modern audio problems.
All filters in the Qure are build in series and have their own OP-Amps, reducing interference to a minimum, and providing individual activation of each filter.
The QURE Control:
The output of the EQ-stage passes through a tube circuit which is constructed based on a mixed voltage-current feedback technique with a high overload tolerance. The circuitry was calculated to produce a THD characteristic of the tube (Type ECC83) realising a pleasant and proper musical sound impression. In this tube, a special circuit coil-capacitor-resistor filter network (LCR) is switched. The LCR network is integrated in the negative feedback path of the tube circuit and thus reacts directly to the dynamic behaviour of the output signal of the EQ. Depending on the dynamic behaviour of this signal, the spectra for THD and phase (sensation timing) are varied by the filter. The resulting frequency spectrum can be varied with the Qure-potentiometer and generates a fresh, brilliant and silky sound atmosphere from the centre region throughout the upper treble range.
The musical operation is assisted by the proportional-Q design of the filter, which realises an automatic and proper sounding reset of amplification or attenuation. A wide frequency spectrum is treated more sensitively by Qure than a narrow frequency cut. The Qure EQs sound very musical and permit more sensitive corrections in sound compared to constant-Q EQs. In revisions of masters or critical program material, the proportional-Q principle simplifies the adjustments of sound nuances making work easier and more efficient.
- 2x 3-Band equaliser with variable notch filters
- Three independent, series connected parametric filters each side
- Qure circuit (tube LCR circuit)
- Mid band with un-balanced "Non-Reciprocal Response" of boost/cut control
- Variable input (-12 dB to +18 dB) and output (-7 dB to +4 dB)
- Hard-Bypass for each filter band and both cut filters
- Master Relay-Hard-Bypass for all filters
- All potentiometers stepped for quick recall
- Central grounding
- Precision CMRR (CCMR 80dB)
- Tube pre-heating to extend operation time
- Oversized, integrated power supply
- Lundahl input & output transformer (input: LL1540, LL1539 output)
- Dimensions: 19" 2 U