Reasonably new to this. This question arises from my search for a new/new-to-me preamp to replace my mobilePre (which, not surprisingly, doesn't provide tracks which stack particularly quietly). I believe that I understand the concept of headroom (i.e. - how hot a (mic) signal can the preamp handle?), but not the measurement units. Units that I've seen include dBv, dBu and VU. (Were I to guess, I'd assume that dB is decibel, v is volt and u unit. But that still doesn't get me grokking statements such as: "at unity gain, the RNP 8380 has a clip point of +27.5dBu (almost 25Volts peak-to-peak)" Are dBv and dBu synonymous? How (if at all) do dBv, dBu and VU relate? References to any good online primer(s) welcome. Thanks kindly. - Richard http://oldWithoutMoney.com P.S. - Like the new forum layout. P.P.S. - And no, I'm not choosing a preamp solely (or even mostly) by comparing specs. But it is a part of the process.