If you were to plug in your cd player or other source directly to your amp, and it was as loud as you'll ever need (and you don't launch the coils out of your speakers), you wouldn't need more than unity gain (0db). Another way to look at this is if your source outputs 1.4 v and your amp takes 1.0v to meet max output power, you wouldn't want gain. Most of the time one is attenuating with a preamp. The advantage with low gain is that you can run the volume pot fairly wide open, with less degredation to source signal. Until the Castanet is buttoned up, I am using a passive control on my bel canto amp, and I can barely turn the the thing a degree or two before it's too loud. I selected the Castanet for these reasons: Selectable impedance output, headphones, the ability to use it as a 1/2 watt SET amp, very low noise floor, choke PS, ability to float ground on the output trannies, single tube design, great design and success building previous kits, the total kit integration and flexibility, and I found I would never need more than unity gain.
Matt
