Pre-amp for Radford STA25 amplifier

It has been suggested that I replace my Radford SC22 pre-amplifier with a more modern one either passive or active. Which models would be worth considering? Good value for the cost but not expensive. Compatible with the Radford valve amp.

 

One benefit of a passive pre-amp is that it adds no distortion, has a completely flat frequency response with normal length cables and doesn't add any significant noise. Consequently, all passive pre-amps will sound the same, so just choose one that has the inputs you need, and looks and price suits.

Valve amplifiers have a high input impedance, so pretty much any passive pre-amp will be compatible.
The only issue with a passive pre-amp is that as there's no gain in the pre-amp, the voltage necessary for the power amp has to come from the sources. Your Radford power amp I think has an input sensitivity of 1.5V. With digital sources, that's rarely an issue, as most digital players output 2V, but may be an issue with analogue sources like tape or FM tuners, possibly phono stages too.

As to active pre-amps, again buy something that has the right facilities as sonically they will be identical if you avoid 'audiophile boutique' high-end products which feature fairy-dust over technical competence.

S.