Electro-Harmonix PLATFORM Stereo Compressor/Limiter Pedal

Sustain Knob: In Compressor mode, sustain adjusts compression ratio. As you turn the sustain knob clockwise, the compression ratio increases. This ratio determines how much compression is applied to a signal once it crosses the threshold. Threshold is the volume level at which the compressor begins working on the signal. In compressor mode, the Platform’s threshold level is fixed at a constant -35dB. In practical terms, the compression ratio determines how much the compressor squashes the signal level and thus how much it levels out dynamics. The higher the ratio, the more it reduces the peaks and valleys in your signal level to yield a more consistent output volume. In Limiter mode, the sustain knob adjusts threshold level. As you turn the knob clockwise, the threshold level decreases and forces the limiter to act sooner on your signal. The compression ratio is constant and—practically infinite—in Limiter mode.

 

Attack Knob: This sets the amount of time delay before the compressor/limiter is activated once the input signal level reaches or exceeds the threshold setting. Turn the attack knob clockwise to increase the attack time from fast to slow. Slow attack settings emphasize the initial attack and add greater pop to your notes (this is great for guitarists who like to chicken pick or play funk). Fast attack settings produce a more even compression where the initial attack is compressed along with the sustained portion of your notes.

Release Knob: While the compressor/limiter is acting on the signal, the input may drop below the threshold setting and obviate the need for compression. However, the compression does not stop working immediately, but gradually stops over a period of time; this period of time is set by the release knob. As you turn this knob clockwise, release time increases, or slows. Slower release settings generally result in smoother, more transparent compression with little or no audible artifacts, while fast release settings allow for louder volumes, yielding noticeable artifacts such as pumping. Pumping can have a musical effect, or it could be detrimental to the signal. Use your ears to determine if it’s beneficial or not. 

Volume Knob: This control—located in the upper left corner of the pedal—is the master output-level controller for the pedal. Use this control to balance your level between bypass and effect mode. 

Knee Button: This button changes the compression/limiting curve to produce a compression sound that is either more transparent, or more noticeable. When the Knee LED is lit, soft knee compression is enabled, and the result is subtler. When Knee is off, the compressor operates with a hard knee response and produces a more dramatic compression effect. A hard knee is recommended for instrumentation where you want a more obvious compression sound. Most effect pedals employ hard knee compression. Hard knee works great with guitar, bass, drums, and keys. The soft knee setting is recommended for delicate instruments or passages. It’s great for vocals, strings, pads, and other instruments where it is important for the use of compression to be as transparent as possible.

Limiter Button: Press this button to engage the limiter. The button lights green to indicate that the limiter is active. A limiter is a compressor that is fixed at an extremely high—practically infinite—ratio. As a result, the signal level does not increase past the threshold setting. The Attack control can still be used to delay the limiter’s attack. The states of the Knee and Limiter buttons (as well as the Drive footswitch) are saved in flash memory and are restored each time the Platform is powered up.

Bypass Footswitch: When in bypass, the entire pedal is bypassed, including the Drive section, no matter the state of the Drive LED.

Drive Knob: This controls the input gain of the overdrive section. As you turn the knob clockwise, the amount of overdrive saturation increases to give you a more distorted sound. Set Drive to a lower setting for a clean volume boost. 

 

Tone Knob: This knob adjusts the frequency response of the overdrive’s high-cut filter, allowing you to dial in a suitable overdrive tone but cutting harsher trebles.  

Drive Volume Knob: This knob is located on the left side of the lower row of knobs, and controls the output volume of the Drive section. Use this knob to balance the output volume between Drive on and Drive off. 

Drive Footswitch & LED: The Drive footswitch allows you to engage or bypass the overdrive section. When Drive is engaged, the white LED above the Drive footswitch lights up. The last state of the Drive footswitch is recalled upon power-up, as with the Knee and Limiter buttons. Please note that the Platform must be in effect mode for Drive to be heard. The Drive section will not be heard if the pedal is in bypass mode.

Swell Knob: The Swell algorithm is triggered every time a new note is played. The normal attack of your instrument is replaced by a sound that fades in slowly. The Swell function is located after the overdrive and compressor functions in the signal chain, but before the main volume knob. Swell has just one control—the Swell knob. Adjust the Swell’s fade-in time with this knob. As you turn this knob clockwise, the fade-in time increases. When the knob is set to zero, the Swell effect is bypassed. Swell mode works best on instruments that have a quick attack and long sustain, such as a guitar, bass, synthesizer, or organ.