KeeleyCompressor Pro Pedal

Keeley Compressor Pro Pedal

The Compressor Pro, from Keeley Engineering, aims to be the last word when it comes to stompbox compressors. In addition to providing razor sharp accuracy, the pedal is also incredibly versatile in that it can be used with an array of instruments. In fact, its ability to accept a wide range of external signals make it ideal for studio compression duties. Concurrently, the pedal also holds its own in live situations, giving players that robust and polished tone they’ve been looking for.

In terms of controls, the Compressor Pro features intuitive front panel controls for Threshold, Ratio, Attack, Release, and Gain. Threshold is essentially the core of the pedal, as it dictates when the compressor is imparted onto the signal and vice versa. The signal is being compressed when the corresponding LED is red, and is unaffected when it is green. It can be adjusted from -50dBu to +10dBu.

Conversely, the Ratio parameter controls the overall amount of compression to be imparted. When fully CCW, the compression ratio is 1:1, though it can be set to infinite (∞:1) when fully CW. In the latter configuration, the output level will never increase–even with an unruly input signal! This is ideal for hard-limiting applications as well as chicken-pickin’.

Compressor Pro Features

• Compression LED Display – 7 Segment LED display for fast and accurate metering of compression and gain reduction (Gain Reduction Levels of -1dB to -20dB are indicated)
• Threshold LED Indicator – Bi-Color LED to indicate when compression is initiated and released
• Exact RMS Analysis (ERA) – Senses the true RMS value of the input program material such as your guitar, bass or drum machine
• Hard/Soft Knee Compression – Hard Compression for limiting or adding sustain, soft knee or Komfort Kompression for gentle compression, keeping performances lively and natural sounding without potential phase issues in parallel, or blending style compression
• Auto Mode – Program dependent Attack and Release times (Set to Auto ON for worry-free performance and automatic Attack and Release times)
• True-Bypass – No tone or signal loss when OFF
• Threshold Range of Adjustment is from -50dBu to +10dBu,  2.45mVRMS to 2.45VRMS – Pro Audio (studio) Levels are +4dBu Consumer Audio Levels are -10dBu;  Passive guitar or bass pickups are typically about -25dBu to 2.5dBu
• Ratio Control – 1:1 to ∞:1
• Attack Control – Times between 0.15ms and 150ms (Controls the time it takes for the Compressor Pro to start compressing)
• Release Control – Times between 0.1s to 3s (Controls the time before the Compressor Pro releases or stops compression)
• Gain Control – Controls the output level of the compressor, does not affect the compression controls like THRESHOLD, RATIO, ATTACK, or RELEASE – Use for Make-Up Gain if set for heavy compression gain reduction (+20dB Boost is possible)
• Knee Switch – Hard/Soft Knee – Hard Knee Compression follows a hard fast rule: If THRESHOLD is met, then Compress at this RATIO – Soft Knee is Komfort Kompression (keep compressed guitar or instrument parts sounding lively and dynamic, without the “blanket” of compression found in many types of compressors)
• Auto Switch – OFF/ON – Set to ON in most cases for automatic setting of Attack and Release Times (This will sound natural and work in a very large number of cases) – The Comp Pro looks at the input signals like guitar, bass, vocals or drums and determines the correct attack and release times depending on what signal levels are being detected
• True Bypass Switching
• Keeley Quality Engineering
• 100% Made in Edmond, OK, USA