We designed our valve amplifier, manufactured it, and put it on the market, and never actually listened to it. In fact, the same applies to the 303 and the 405. People say, 'Well that's disgusting, you ought to have listened to it.' However, we do a certain amount of listening tests, but they are for specific things. We listen to the differential distortion - does a certain thing matter? You've got to have a listening test to sort out whether it matters. You've got to do tests to sort out whether rumble is likely to overload pickup inputs, or whether very high frequency stuff coming out of the pickup due to record scratch is going to disturb the control unit. But we aren't sitting down listening to Beethoven's Fifth and saying, 'That amplifier sounds better, let's change a resistor or two. Oh yes, that's now better still.' We never sit down and listen to a music record through an amplifier in the design stage. We listen to funny noises, funny distortions, and see whether these things are going to matter, to get a subjective assessment. But we don't actually listen to program material at all.