Substrate is a bass enhancer.

This effect device to give your bass sounds the right "boost". It will generate additional harmonics to the sound in the low end frequency range (sub-harmonics) based on a pre-set fundamental frequency from which it will generate the harmonics. These harmonics can be added and amplified by a "boost level" which results in a bass sound with more power in the low end range.

The second advantage is, if the frequency is set exactly to the fundamental frequency of a sound, the generated harmonics will produce a "psycho-acoustic effect" that gives your brain the feelings to perceive the sub frequency range of a bass sound on weak systems that can't reproduce such low frequencies (like weak laptop speakers or mobile devices), even if these low frequencies are not really audible.

• Frequency control to set the fundamental frequency in Hz from which the harmonics will be generated. This is a special designed filter to only leave the set fundamental frequency of the processed sound. All other frequencies above and below the set frequency will be cut out.
• Boost control to generate addidional harmonics based on the set fundamental frequency. The higher the amount of this control, the more harmonics will be generated and amplified.
• Invert Phase control. In some cases the processed signal can cause phasing issues or phase cancellations when it will be mixed back to the original signal. Inverting the phase of the processed signal can prevent such phasing issues. And in some other cases inverting the phase also can result in an even fatter low end.
• Boost Mix control to set the level of the processed signal to mix it to the unprocessed dry signal.
• Dry Mix control to set the level of the unprocessed dry signal.
• Mute Boost control to mute the processed signal.
• Mute Dry control to mute the dry signal.
• Main Volume control for setting the main output volume level.