SPL PASSEQ 1650 Passive Mastering Equalizer – Black

SPL 2595 PQ – Passeq Equalizer

SKU: SPLPASSEQ2-BK Categories: , ,


Passive Mastering Equalizer

The new dual-channel PASSEQ (Model 1650/1654) is the resolute evolution of the highly acclaimed predecessor Model 2595.

The new PASSEQ now features Air band, a stepped output control ranging from -10dB to +10dB and a mid cut band now starting at 200Hz. These features were on the wish list of many mastering engineers.

Furthermore we have exchanged capacitor arrays in the filters by custom-made single capacitors and optimized the bandwidth per frequency range. This evolution is a sonic revolution.

The components in a passive filter such a variable resistor, capacitor and coil deliver a special sonic character. An important part of the sound is played by coil and capacitor loading and saturation characteristics. The resulting inertia in contrast to the fast reaction of active filters is the reason for the pleasing sound that we get from passive designs.

We tend to perceive these attributes in terms of an increased suppleness and transparency, with perceptibly improved, silky highs and warm and punchy basses.

The first generation Passeq was the first passive equalizer that offered high, mid and low band with individual boost and cut and with 12 selectable frequencies per band. Passeq was the most powerful passive EQ system ever made with a total of 36 boost and 36 cut frequencies. The sheer amount of possible frequency curves or shapes is close to 3 million.

Now, here is the 2nd generation: the new PASSEQ Mastering Equalizer. It features the same amount of boost and cut frequencies, though the choice of frequencies is altered and the Q-factor is more musically adjusted for each selectable frequency.

With 72 static filters every channel (36 x Enhance, 36 x Cut), the Passeq exceeds all previous styles of this kind by a wide margin. Each network is divided in to 3 Cut and 3 Boost bands, each providing 12 switchable regularity selections. The Cut and Improvement arrays are not identical; crossovers are made to partner with like an accurate mechanic cogwheel so about enable the engineer accessibility to the biggest possible amount of superior, wide-band S-curves with variable pitches.

An additional amazing Passeq attribute is its individual sonic adjustment of each inductive filter through different coil/condenser/resistor combos: In stark contrast to earlier filter style and building, each Passeq filter is optimized for the frequency assigned.To guarantee the very best feasible signal heat, exuberance and musicality in processing, coils for important voice regularities are personalized for the Passeq.This attains the widest feasible range and tonally enticing noise shade scheme from any type of passive EQ.


Max. Input Level: + 32.5 dBu
Input Inpedance: 20 kOhms (balanced)


Max. Output Level: + 32.5 dBu
Output Inpedance: ‹ 600 Ohms (balanced)

Harmonic Distortion:

at -30 dBu: 0.076%
at -20 dBu: 0.026%
at 0 dBu: 0.026%
at +10 dBu: 0.0086%
at +30 dBu: 0.0012%

Noise (unweighted, (Gain +0 dBu, EQ = 0dB B/C): - 91.8 dBu

Noise (A-weighted, (Gain +0 dBu, EQ = 0dB B/C): - 95.2 dBu

Noise CCIR, (Gain +0 dBu, EQ = 0dB B/C): -86.2 dBu

THD & N (Gain +0 dBu, EQ = 0dB B/C): › 102 dB

Common-Mode-Rejection: › -60 dBu
(bei 1 kHz, Gain +0 dBu, EQ = 0dB B/C)

Transmission Bandwidth (-3 dB):

10 Hz – 200 kHz

Frequency Range:

10 Hz – 35 kHz

Power Consumption:

0.06 Amp, 230V/50Hz, 9.5 Watt, 13.6 VA
0.09 Amp, 115V/60Hz, 9.5 Watt, 13.6  VA


230 V/50 Hz: 0.5 Amp
115 V/60 Hz: 1  Amp


Standard EIA 19 Inch Housing/4U, 482 x 177 x 311.5 mm / ca. 19″ x 7″ x 12,25″


10.2 kg / 22.5 lb




Additional information

Additional information

Weight 37.5 lbs


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