The Liquid Pre is a purist's dream: a passive preamplifier with only an input selector and volume control, using the highest quality input and output connectors, and eschewing the use of transformers.
Transformers are not necessary in this unit because it employs Liquid Cable technology throughout, which effects perfect impedance matching between source and amplifier, and the liquid cable conductors scale volume exceptionally well. The Physics article and the Technical Background article give insight into the reasons for use of liquid conductor material.
The Liquid Pre embodies simplicity at its highest level, as does a racing yacht or a Formula One car.
Judciously placed vibration control materials are located within the case of the Liquid Pre for the purpose of tuning, as the performance of the Liquid Pre is so refined that everything matters. In fact the center foot on the bottom of the unit is interchangeable for the purpose of voicing the system in which it is used: soft to hard. Even placing a thin item such as a business card under the center foot can tailor the sound. Similarly, one does not want to place anything on top of the Liquid Pre such as a book, as it will be detrimental to the performance.
Four pairs of inputs and one pair of outputs are standard. Single ended RCA only.
The input selector switch is hand modified from using two NOS units with the correct specifications.
The volume control is a 23 position stepped attenuator and is a modified hand built unit.