ER-130 Eurorack Voltage Controlled MID-SIDE Unit



€ 600

ARREL Audio ER-130 Eurorack Voltage Controlled MID SIDE (M/S) Unit is the answer to all stream creative needs for EURORACK synthesizers. Its features set it apart from other similar products on the market due to a very high fidelity approach used for the design of the electronics together with the use of high quality components. The internal circuits of the ER-130 have been directly derived from the ARREL Audio professional units in order to obtain maximum sonic performances.

MID/SIDE processing is based on the coding of a stereo signal into two components. The “MID” channel contains the information that appears in both the left and right channels (monophonic content), and the “SIDE" channel contains all the information that differs between the left and right channels (stereophonic content).

Once encoded into M/S, these two signals can be “creatively” processed independently, before being decoded back into the L and R channels. The M/S technique gives control over the width of the stereo image. In addition the ER-130 provides insert points on the MID and SIDE channels for the insertion od Voltage controlled Eurorack units for the maximum "creativity".

On top of its amazing sound quality, the ER-130 MS unit features a unique set of functions.

  1. Manual (zero detent) and CV (Control Voltage mode) switch, the control Voltage range [0V, +5V]) but it can accept up 0 +12 V (attenuation control)
  2. High quality analog M/S Matrix
  3. Unbalanced in/out
  4. By-pass push button
  5. LO-CUT filter on the SIDE
  6. Inserts on MID SIDE channels with on off switch
  7. Multicolor stereo depth display
  8. Peak indicator (Out signal and CV)
Number of Channels: 2, Stereo Unit
Power Supply Eurorack Standard
Power Consumption 3.5 W
Input Stereo, unbalanced, Level 0 dBu max +20 dBu Impedance > 5 KΩ
Output Stereo, Unbalanced,
Bandwidth 5 - 60.000 Hz -1dB, perfect square wave up to 20 KHz
Distortion + Noise <0.003% ( typical 0.001%).
Side Control Voltage [0, +5V] Can accept up to +12 V (Attenuation potentiometer) 10 Kohm impedance.
Front Panel Controls By-pass button Stereo width LO-CUT on off button LO-CUT cut off frequency knob Stereo width control knob Control switch CV modulation depth control
Front Panel Input Connectors 2 x 3.5 mm jack for the stereo input , 2 x 3.5 mm jack for the stereo output 2 x 3.5 mm jack for the MID insert 2 x 3.5 mm jack for the SIDE insert 1 x 3.5 mm jack for the CV INPUT
Front Panel Indicators BY-PASS LED PEAK LED STEREO WIDTH DISPLAY
Rear Panel Connectors Eurorack power supply connector
Construction 28U TE Units (142mm)
Dimensions W 142 mm, H 128 mm
Weight 500 g

    ER-130 Key-Technologies

  • LARGE BANDWIDTH (LBW)

    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.
  • PERFECT SQUARE WAVE (PSW)

    Large bandwidth plus very low total harmonic distortion means a perfect square wave reproduction.
  • ULTRA LOW NOISE (ULN)

    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)

    High Dynamic Range (HDR) means that the saturation probability of the output stages is very low. This is obtained by using a step up transformer in the output stage.
  • ELECTROMECHANICAL FAULT TOLERANCE (EFT)

    Electro-mechanical 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 (THT)

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

    FAQ 1: What does it means MID-SID coding and decoding (MID-SIDE MATRIX)?

    MID/SIDE processing is based on the coding of a stereo signal into two components. The “MID” channel contains the information that appears in both the left and right channels (monophonic information), and the “SIDE" channel contains all the information that differs in the left and right channels (stereophonic information).

    Once encoded into M/S, these two signals can be “creatively” processed independently, before being decoded back into L and R channels. The M/S technique gives control over the width of the stereo image. If the change of the stereo width varies with time very interesting "spatial" effects can be obtained. The ER-130 is a code/decode /stereo system to be used primarily for Eurorack synths in live and recording applications.

    FAQ 2: Is the ER-130 a voltage controlled MID-SIDE unit ?

    Yes the ER-130 is a Voltage Controlled (CV) unit. The parameter that is voltage controlled is the Stereo Width. In the ER-130 the Stereo Width can be changed by using a manual control, or, vice versa this parameter can be controlled by an external CV.

    The range of values for the SIDE gain is [-50 dB (0 V for CV), +20 dB (+5v for CV)].

    FAQ 3: How can I use the ER-130 in a creative way ?

    1. The stereo image can be controlled manually or by using an external control voltage. In this way we can generate non static spatialization effects.
    2. The two inserts on the MID and SIDE channels can be connected to external voltage controlled Eurorack units to obtain non stationary processing (equalizers, delays etc...). In this way the ER-130 becomes a "HUB" for non stationary spatialization effects.