Empirical Labs PUMP Classic Knee Compressor 500 Series Module

PUMP is a single channel, 500 series rack mount compressor loaded with the kinds of features and performance you’ve come to expect from Empirical Labs.

PUMP features an Input Level control with a clip indicator labeled "BAD." It offers 8 selectable compression ratios ranging from 2:1 to 20:1, each with its own distinct curve. The unit provides precise recall with digitally-stepped knobs for independent control over Attack and Release, including a soft, Opto-Coupler-style Release. PUMP also includes a switchable 110Hz High Pass Filter, detailed Gain Reduction metering, and Attack Modification (AtMod) to slow the attack onset, preserving transients for more impact, plus a Bypass option for a dry signal.

Specifications
Frequency Response – 5 Hz to 175 kHz (-3dB points).
Dynamic Range – 125 dB from maximum output (.5%THD soft clipping) to minimum output. Noise floor with Output on 0 is typically – 101dBu.
Distortion – between .0035% and 15% at 1KHz, depending on mode and settings.
I/O – Maximum Input before hard clipping – +22dBm, “ Line In” mode. Maximum Output (Mix at 0) – +28.5dBm
Impedance – 120k Ohm, Instrument In Mode, output impedance is less than 75 ohms. 20K input impedance in balanced Line in mode.
Compressor Time Constants – Attack: 200µs to 40ms. Release: 50ms to 500ms, plus Opto setting. Stereo Linkable for stereo tracks.
Detector HP Filter – Switchable, fixed at 110Hz
Attack Modification (AtMod) – Slows the initial onset of the attack envelope allowing more transient back into the track.
Saturation Soft Clipper – based on the same circuit found in the Mike-E CompSat section.

US and EU parcels ship via UPS, ETA 1-7 working days from pickup day zero. That also applies to most locations worldwide.

All shipments are fully insured.

Bigger shipments requiring pallets or custom made crates ship to US, CA, JP, CN, AU and other outside of EU locations via DHL Air Freight, ETA is normally approx. 7-14 working days from pickup day zero.

Big shipments inside EU ship via different freight companies, recently mostly via ACE Logistics. Freight forwarders can use different courier companies for deliveries to final destinations.

Palletising and crating time can vary depending on the size of the shipment and packaging queue. We pack all our shipments with great care.

You are most welcome to pick your order up yourself from our Retrosonic Pro Audio showroom, studio and warehouse in Tallinn, Estonia.

We ship worldwide – contact us for a personal shipping quote or any other questions.

VAT (Value Added Tax) can be deducted if you have a company with a valid EU VAT number or if you're based outside of the EU. Non-EU buyers pay all and any import tax and duty as regulated by their local customs.