Olethros II, Sunn Beta dual preamp (Lead/Bass)

Beta Lead preamp, Beta bass preamp in a pedal
A preamp in a pedal, based on the 'notorious' Sunn Beta.
OLETHROS II (Όλεθρος II) is the 2nd version of our Beta preamp series.

What's new on this 2nd version:
  • A toggle switch for each channel lets you select between the Beta Lead and the Beta Bass version of the preamp.
  • A 3-position toggle switch  (one for each channel) lets you shift the mids in a different point of the spectrum: 550Hz, 850Hz, 1200Hz.
  • Besides the LINE out which is used to connect the OLETHROS with a power amp an INSTRUMENT output has been added so that you can easily use it as a pedal.
 Description:
Just like the original, this p
re-amp features two separate channels A&B that can be combined or used independently. Each channel has its own separate controls (triple EQ, Gain, Volume) and two footswitches allow you to switch between channels (A/B) or activate both at once (A+B). A bypass footswitch is also available. Each channel has its own FX Loop that can be used to connect effects of your choice.

You can connect OLETHROS directly to a power amp through the LINE OUT jack.
Alternatively an INSTRUMENT output is also available in case you need to use the preamp as a pedal.
 
VOLUME and MASTER potentiometers are Logarithmic in order to give you a better control of the volume, especially on lower settings. This pre-amp has massive amounts of volume so make sure you start experimenting with it at low volume levels at first.
 
A balanced output has been added and it's accessible through an XLR connector in case you need to route the pre-amp's signal through a balanced cable. The balanced output's level is not affected by the Master knob.
 
The pre-amp requires a 9Volt DC power supply that should be capable of providing at least 200mA of DC current. We have designed and added internally an extra circuit which produces the necessary voltages (+15, 0, -15) the pre-amp requires to work properly with the proper headroom and volume capabilities.

specifications:
  • Two channels A, B, switchable through footswitches (A/B, A+B)
  • A toggle switch for each channel lets you select between the Beta Lead and the Beta Bass version of the preamp.
  •  A 3-position toggle switch  (one for each channel) lets you shift the mids in a different point of the spectrum: 550Hz, 850Hz, 1200Hz.
  • Separate controls (EQ, gain, volume) for each channel & Master volume control.
  • FX Loop for each channel (SNDA/RTNA, SNDB/RTNB)
  • LINE Out. Use it to connect the preamp directly to a power amp or mixing board.
  • INSTR. Out.  Instrument level output, use it for "effect pedal" operation.
  • XLR Balanced Output. The Master knob doesn't affect the volume of this output.
  • Required Power supply: 9V DC. The circuit needs at least 200mA to work properly.
  • Polarity: Negative tip.
  • Enclosure dimensions: 8.74 x 5.75 x 2.01in (222 x 146 x 51 mm)
  • Weight: 1kg
Nomenclature:
OLETHROS (Greek: Όλεθρος) can be translated as 'ruination','destruction','devastation', 'destruction', 'annihilation'.
In Ancient Greek mythology Olethros was the personification of havoc and was probably related to the demons and spirits of combat and battle.