Microphonic

Microphonic is the tendency for something to act like a microphone, amplifying sound traveling in air. Most bits of electronics are microphonic to some degree: capacitors, circuit boards, transistors and, in particular, tubes. Tubes are delicate metal constructs housed in a vacuum sealed glass envelope. Tap your finger on a tube and the sound can easily be heard through the system. Our highest end analog audio products use vacuum tubes; not because they're microphonic, but because they sound sooo much better than any solid state design I have heard in my 40 years of building products. So the question arises, what impacts do microphonic components have on the music? I have suggested for many years that one possible benefit to vacuum tubes in preamplifiers is microphonics. Preamps generally are in the same room as loudspeakers and they hear what's played on them. In other words, tubes re-amplify that which we play on our speakers, in a type of loop. And while the re-amplified signals are low, they're not silent. They add to what we hear. And here's the kicker, their sonic additions are delayed in time by the air sound travels through. This delay is, in effect, reverb - which is always a nice touch for added ambiance. How much reverb is added? It depends greatly on a number of factors, including chassis construction, type of tubes, circuit topology, etc. And how much does this matter? It's hard to say, but interesting to discuss. It ain't nothin'