Preamps & Gain
Why microphones need a boost, and where that boost comes from in this studio.
Three signal levels
Every source in this room speaks at one of three volumes. MIC LEVEL is a whisper — a microphone converts air movement into a tiny electrical signal, thousands of times quieter than what a recorder wants. LINE LEVEL is conversational volume — the standard strength that interfaces, synths, and Logic all expect. INSTRUMENT LEVEL sits in between (electric guitars, the Clavinet's pickup).
What a preamp actually does
A microphone preamplifier raises a whisper to conversational volume: roughly 30–60 dB of gain, cleanly, without adding hiss. That's its whole job. Every mic in the locker must pass through one before Logic can use it.
Why the Volt has preamps on every input and the AudioFuse doesn't
The Volt 876 is the studio's front door for microphones: eight channels, each with its own preamp, phantom power, and metering. The AudioFuse expander is wired as the front door for synthesizers — and synths already output line level. They don't need a whisper-to-speech boost, so those inputs don't need preamps. That's also the answer to 'why do line-ins barely need gain': the Prophet, the Minimoog, the Moogs — they arrive at full strength.
One performance, two channels (5 + 6)
The pedalboard rig ends at the J48 DI, which splits the signal: THRU feeds the Princeton amp (captured by the SM7B on channel 5) while OUTPUT goes straight into channel 6. Recording both gives two flavors of the same take — the direct pedalboard sound and the amp's character — to blend later. This is why channels 5 and 6 are always armed together for that rig.
CloudLifter vs. turning up the preamp
The SM7B is famously quiet — it can demand 60+ dB. Any preamp pushed to its ceiling gets noisier. The CloudLifter sits between the SM7B and the Volt and adds a fixed +25 dB of very clean gain, so the Volt's knob can rest in its comfortable middle range. Think of it as splitting the climb: the CloudLifter does the first flight of stairs, the preamp does the rest with fine control. You still set the actual level with the Volt's gain knob — the CloudLifter has no knob at all.