Promitheus Audio Reference EI Core Dual Box TVC preamp. Asking $550 which includes PayPal fee and shipping to CONT US location.
Second owner, light usage, in good condition, minor blemishes.
The Promitheus EI Core Dual Box TVC is a passive magnetic preamplifier which uses transformer-based attenuation with electromagnetic coupling and doesn’t rely on additional resistance. The transformers with copper windings have very high impedance across the audio band. Entry level Passive Preamplifiers are typically resistive passives that cause large impedance values with additional resistance in part to accomplish attenuation.
The use of transformers dramatically improves the ability of the Passive Preamplifier to drive cables (and loads) compared to traditional designs. Very little of the source's output power is lost and only the very low winding resistance appears in series with the source prior to the preamplifier's output.
The TVC is more costly to properly implement since the best transformers are very expensive. Promitheus Audio has been designing and manufacturing its own transformers since 2003. Solid iron cores used in the EI Core TVC serve as an excellent pathway to provide magnetic flux.
From Nicholas Chua at Promitheus Audio:
Dual Box Advantage
The dual units are sonically superior to single box designs because they
have better macro and micro isolation. They are made from merbau wood, which is very durable and mostly from areas in South Asia, New Guinea, Pacific Islands and Queensland; The dual box cuts vibration to zero as both transformers are totally isolated from each other; No electro magnetic interference between left and right transformer; When there is music the transformers radiate a magnetic field and this magnetic field can effect each transformer. Keeping them separate will reduces this effect.
Dual Mono Advantage
Dedicated volume control provides separate balance and volume controls,The separate volume controls also offer better performance in these areas:
Sound staging, Channel separation, Imaging, Depth, and Transparency.
