CD player straight into amps?

I have been an active preamp guy forever, but I have recently been experimenting with the Promitheus Audio Reference Dual-Box TVC for use in a second system. I have been playing with this little point-to-point hand-wired passive pre in my reference system while I am waiting to fully assemble this second system, and the quality and transparency of this inexpensive component have been a real eye-opener. (This thing plays WAY out of its price league.)

I think a high quality TVC like the reference version of the Promitheus component is a great alternative to a traditional active pre if you have high quality source components and the input sensitivity on your amplifier is compatible. A TVC can give you all the transparency of a direct connection between your CDP and amplifier. It is potentially a better alternative than a direct connection if the volume control on your CDP is not first rate or if the additional current and alternative input/output impedances offered by the TVC prove to be a better way to drive your cables, preserve dynamics and overcome some of the other drawbacks often associated with the elimination of a preamp or the use of a resistor-based passive.

Just one point of clarification on the topic of passive preamps. There can be quite a difference between the performance of a resistor-based passive preamp and a transformer volume control (TVC) passive preamp in any given system.

Resistor-based passives require careful impedance matching, and they generally demand a short interconnect between the passive and the amp. It is possible to have source components and amplifiers with output and input impedances that are simply incompatible with a resistor-based passive approach regardless of the input impedance selected for the passive.

TVCs are generally more forgiving - especially if you are running amplifiers with low input sensitivity. The more a TVC is allowed to attenuate the input signal voltage coming in from the source component, the lower the output impedance and the greater the level of current at the TVC output. The low output impedance and the higher current allow the TVC to drive the interconnects and the amplifier more effectively.

So TVCs are at their best when they apply significant attenuation to the source component signal, and they can often drive long interconnects without any problem. Resistor-based passives are at their best when they are applying little or no attenuation, and they always require careful impedance matching and short interconnects in connecting with the amplifier.

Bad experiences with passives usually result from a mismatch or incompatibility problem in one of the areas mentioned above or from insufficient output voltage from the source as compared with the input sensitivity of the amp.