SPL Crescendo

SPL Crescendo

Eight-Channel Microphone Preamplifier featuring 120V Technology

The Crescendo is the first microphone preamplifier which operates with an internal operating voltage of 120V. Making it absolutely unique, because with the 120V Technology it is nearly impossible to overdrive this preamplifier. The Crescendo excels with absolute signal fidelity and clarity. Rediscover your microphones, they have never been amplified like this.

High-Voltage Preamplifier

Imagine a microphone preamp which has a dynamic range and distortion limit so huge, that you can record all dynamics of your microphone without any limitations. Additionally, imagine there is no influence on the sound through preamp electronics, and you can experience the sound of your microphones like never before. This is Crescendo.

SUPRA Op-Amp

Thanks to the discrete buildup with our proprietary high-voltage amplifiers, the SPL SUPRA op-amps, and thus a possible internal operating voltage of +/- 60V (120V Technology), the Crescendo provides unprecedented technical performance data. Crescendo is capable to amplify even the fastest transients, the finest details and the complete frequency range, clean and almost without any distortion.

Mic Gain

Use the Mic Gain for the setting of the pre-amplification. You can control a range from 18dB to 70dB. For high-level signals, which do not need to be amplified that much, you can use a PAD with -20dB. Thus the control range of the amplification is shifted to -2dB to 50dB.

In and Output Stages

The differential amplifiers in the input stage are built-up with transistor pairs, consolidated in in a special housing. A precise matching of the transistors as well as thermal coupling guarantee a high common mode rejection and extremely low THD values. The choice of transistors and electrical resistors has a massive impact on the sound. Within countless listening sessions, the perfect components for the Crescendo were chosen – It was well worth the effort!

Servo

The discrete op-amps of the output stage are able to drive long cable paths without any problems. The output stages operate as current amplification, which, with 6mA quiescent current, also provide mere Class A operation. We almost completely renounced to use coupling capacitors, to avoid their sonic disadvantages (diffuse, blurring, loss of dynamics ). However, to eliminate DC voltage, active servo circuits are used.

Additional Features

Each of the eight preamplifier sections of the Crescendo provides individual gain control (Mic Gain), an own VU meter, phase reversal switch, phantom power, a -20dB PAD switch and a reduction for the display of the level on the VU meter (VU -10).

Power Supply

The toroidal transformer power supply is integrated in the housing of the Crescendo. To avoid electrical interference from the power supply on the preamplifier, the power supply is shielded with a special Mu-metal sheet. The transformer itself is also Mu-metal encapsulated.

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Specifications

Frequency range

• 20-50kHz, -3dB

Mic pre amp gain

• 70 dB (regelbar über Potentiometer)

Input impedance

• 10 kOhm

Output impedance

• < 600 Ohm

Noise (A-weighted)

• (60dB Gain) -69.7 dB (30dB Gain) -87.5 dB

FFT

• (60dB Gain) -96dBu (20 dB Gain) -120dBu

CMRR

• (60 dB Gain) > 65dBu/1kHz
• (30 dB Gain) > 75dBu/1kHz

THD/N

• (60dB Gain) 0.04%
• (30dB Gain) 0.008%
• (10dB Gain) 0.00009%

E.I.N

• (60dB Gain) 150 Ohm 129.5 dB
• (60dB Gain) 40 Ohm 134.4 dB

Power consumption

• 230V: 51.6 W
• 115V: 50.5 W