Here's what EBS say
Built-in Compressor. The option to add compression make possible to keep the note differentiation clearly audible even at heavily distorted sounds. There are three modes for the built-in compressor, High, Mid and Off. For the Mid setting, there's an additional trim pot inside to set the ratio. There's also a trim pot to set the Threshold for the compressor (affect both settings).
Clean Loop, Drive Loop - Endless possibilities! The Billy Sheehan Signature Drive offers unlimited pre-post mix tone shaping, made possible by including a clean loop and a drive loop. It lets the user insert any other effect they wish within each loop to ’pimp’ the effect into your own signature effect! For example, connect an external EQ to the Drive Loop and shape the character of the distortion any way you want. Or, turn off the built-in compressor if you prefer to use a different type of compressor and put in the Clean Loop. To use the loop function, you need an additional insert cable (a stereo 1/4" plug that split in a tip and ring female or male 1/4" mono plug).
Controls. With the new extended size box from EBS, there are controls for Drive (gain for the overdrive engine), Tone (sets the frequency scoop for the drive), Level (sets level for drive channel post Drive Loop and pre final compressor) and Clean (sets level for the clean channel, post Clean Loop and pre final compressor). The concept works similar to when you blend the two channels on the preamp of a Fafner II amp.
- Nominal Input Level - 8 dBv
- Input Impedance 700 kohms
- Gain Range Drive 20 - 40 dB
- Tone Filter Range 175 - 4500 Hz Q 0.6
- Nominal Loop Level -8 dB
- Output Impedance Loops 2 kohms
- Input Impedance Loops 47 kohms
- Mix Level
- Drive Channel +3 dB max
- Clean Channel +6 dB max
- Ratio 5:1 (max)
- Threshold -25 +6 dB
- Attack Time (80%) < 10 ms
- Release Time (80%) 100 ms typ
- Makeup gain 0, +3, +6 dB
- Output Impedance < 100 ohms
- Dimensions W x H x D 3.5" x 4.5" x 1.4" (90 x 115 x 35 mm)
- Weight 480g (1.07 lb.)
- Type Analog Effect, Mechanical Switching
- Power Requirements 9 - 12 V DC Regulated, 15 mA max