R-504 2 Baxandall (BAX) Bands + LO-CUT and HI-CUT

€ 610

R-504 is an advanced single-channel equalizer conceived to offer to the API 500 user the superior audio performance of the ARREL Audio high level series products. The unit offers to the 500 user high reliability, rugged design, outstanding audio quality, versatility and ease of use typical of the tradition of ARREL Audio products.

The R-504 equalizer is based on the Livio Agentini’ s "Single-Stage Parallel Configuration" patented design. This innovative phase coherent EQ design offers the lowest distortion/noise specifications, not available in other products.

The R-504 filtering section offers LO, HI Baxandall (BAX)filters with two switchable shapes. The Emphasis/De-Emphasis control range is +/-14 dB. The HI-CUT and LO-CUT filters are characterized by 12/dB Oct. slopes and variable cut-off frequency control.

Each filter section can be individually activated by a button (LED). A bypass button is used for a true analog by-pass function (LED).

R-504 is is one of the models of the serie of equalizer that ARREL Audio conceived for the 500 series (the other models are R-502, R-503, R-505) in order to give to the user the best choice for its application.

Number of Channels: 1
Power Supply +/- 16 V DC, very low power supply currents with respect to the API 500 standard
Power Consumption TBD
Line Input Elecronically Balanced,
Impedance 20KΩ,
Input Level +4dBu,
Max +20 dBu.
Output Level Electronically Balanced,
Level +4 dBu, Max +24 dBu,
Output Impedance 100 Ω
Bandwidth 5 - 150 KHz +/-1 dB, perfect square wave up to 20 KHz
Distortion + Noise <0.003% ( typical 0.001%).
Front Panel Controls True By-Pass button (LEDs) for the three filter sections (SHELF, HI-CUT, LO-CUT),
Shelf Gain (Emphasis/De-Emphasis) pot control, Range +/- 14 dB with center detect (2 controls),
Shelving shape control (LO and HI) switchable (2 shapes),
Cut-Off Frequency control for LO-CUT and HI-CUT(2 controls).
Frequency Bands LO: Shelf Shape, two position switch (two shapes),
HI: Shelf shape, two position switch (two shapes),
LO-CUT: 20/200 Hz, Slope 12 dB/Oct, Cut-Off frequency continuous control,
HI-CUT: 4000/16000 Hz, Slope 12 dB/Oct, Cut-Off frequency continuous control.
Rear Panel Input Connectors API 500 compatible connector
Construction Compliant 500-series rack with PSU and external audio connections,
Single 500-series rack slot required for each R-501 module.
Dimensions Standard API 500
Weight TBD kg.

    R-504 Key-Technologies


    Large Bandwidth (LB) means a very fast transient response able to represent the original sound with the maximum temporal resolution. LB is required to improve the perception of a “real sound” and to represent the details of the original sound.

    Large bandwidth plus very low total harmonic distortion means a perfect square wave reproduction.

    Ultra Low Noise (ULN) active and passive components and ULN design techniques. This requirement is especially important when the audio bandwidth is large as in the case of ARREL Audio products.

    High Dynamic Range (HDR) means that the saturation probability of the output stages is very low. This is obtained by using special rail to rail circuits and by increasing the power supply voltage of the analog circuits.

    Electromechanical tolerance means that electromechanical components are doubled in every situation in which maximum reliability it is important due to a frequent use (switches, push buttons, potentiometers).

    Through Hole technology means the maximum reliability in terms of thermal and mechanical stresses especially for connectors and electromechanical components.

    Special patented circuits guarantees very low phase distortion in ARREL equalizers and filters.