Buses
o Common signal path where many signals can be mixed
o Typical buses
• Mix bus
• Group bus (or single record bus on CD)
• Aux bus
• Solo bus
• Processors vs. Effects
o A dry signal is the unaffected audio, while a wet signal is the affected audio
• For processors, can adjust the percentage used between wet and dry
o Processors: Made to alter the input signal and replace it with a processed signal
• Added with an insert point
• Include EQs, dynamic range processors (such as compressors, limiters, gates, expanders, and duckers), distortions, pitch correctors, faders, and pan pots
o Effects: Add something to the original sound. Takes signal and generates a new signal based on original one
• Added by using an auxiliary send
• Include time-based effects (such as reverb, delay, chorus, flanger), pitch-related effects (such as pitch shifters and harmonizers)
• Basic Signal Flow
o Step 1: Faders, pan pots, cut switch
• Each channel is fed from a track on the multitrack recorder. Signal travels from the line input socket, the fader, then the pan pot.
• Pan pots take the mono signal and send out a stereo signal, then sum it into the mix bus. Single fader alters the level of the stereo bus signal.
• Then, mix bus signal goes to two mono outputs on the back of the console (L, R)
o Step 2: Line gains, phase-invert and clip indicators
• Line-gain (or tape-trim) boosts/attenuates the level of the audio signal before it gets to the channel signal path
• Optimize the level of the incoming signal to the highest levels possible without clipping (digitally) or unwanted distortion (using analog)
• Some engineers use the over-hot input because it adds appealing harmonic distortion
• Check phasing with the phase invert
• Don’t always trust clip indicators, trust your ear above all else
o Step 3: On-board processors
• Quality dictates much of a console’s value
• Include hpf, EQ, basic compressors at times
o Step 4: Insert points
• Many engineers prefer to use external insert points rather than in-board.
• Lets us insert devices into the signal path
• Each external unit can only be connected to one channel, but multiple tracks can use the unit through inserts.
• Can use multiple inserts on a single track
• Importance of Signal Flow Diagrams
o Step 5: Auxiliary sends
• Takes a copy of the signal on the cannel path and sends it to an auxiliary bus
• Local aux controls are on the individual channels, containing:
• Level control: pot to control level of the copy sent to the aux bus
• Pre/post fader switch: determines if the signal is taken before or after the channel fader. Post-fader lets you control level of signal with channel fader. We often want aux effect level to correspond to instrument level, so we use post-fader feed. If pre-fader, the level is independent of the channel fader and will play regardless of channel fader level.
• Pan control: Aux buses can be mono or stereo. If stereo, pan pot available to determine how mono channel signal is panned to the aux bus
• On/off switch: Often called MUTE
• Master aux controls in master section. Same as the local ones, but no pre/post fader. Most have multiple auxiliary buses
o Step 6: FX returns (or aux returns)
• Dedicated stereo inputs that can be routed to the mix bus
• Provide quick and easy way to blend an effect return into the mix, but offer very limited functionality
• When possible, effects are better returned into the channels
• Groups
o Control grouping: Allocate a set of channels to a group, so moving one fader controls all of them
• VCA grouping: Consoles with motorized faders have master VCA group faders. Individual channel faders are then assigned to a VCA group
• Cutting or soloing VCA group affects each channel assigned to it
o Audio grouping
• To handle many signals, must sum a group of channels to a group bus (subgrouping). Group signal can then be processed and routed to the mix bus.
• Format: Channels:Groups:Mix-buses
• Ex: 16:8:2 denotes 16 channels, 8 group buses and 2 mix buses (or 1 stereo mix bus)
• Routing matrix: collection of buttons that can be situated either vertically next to fader or in its own area. Depress one, and the channel will be sent to the corresponding master group
• In-line grouping
• Ex: In a 24 track recording, drums may be ch 1-8. They are routed through the matrix to Channels 24 and 25 that now function as a group.
• Bouncing: by sending groups to yet another subgroup, we then send that final subgroup to an available audio track on the multitrack recorder
o In-line consoles
• The desk accommodates two types of signals:
• Live performance signals: Are sent to a group to be recorded onto the multitrack
• Multitrack signals: Already recorded information sent to a group
• In-line consoles and mixing
• Since the channel path is stronger than the monitor path, it’s ideal to use the channel path for multitrack recording and return signals and use the monitor path for:
o Effects returns
• Ex: We can send a guitar to line 1 inputs to a delay unit and bring the delay back to the monitor path on the same channel strip/module
o Additional aux sends
• Ex: We can send the background vocals on a bus to a group, the group to the delay and/or reverb. The bus acts as a local aux send while the group channel acts as a master fader of what is being received.
o Signal copies
• Ex: Multiple snare tracks sent to a single channel through the monitor path
o The Monitor Section
• Monitor output
• To hear it, it needs to be sent from the mix output (we commonly use Pro Tools 1 - 2 on the patch bay, and MIX pressed on master channel) to the 2 Track Recorder (2TRK button on master channel). Then, to the monitor output (the actual monitors)
• Additional controls
• Cut: cuts monitor output. Feedback, noise bursts, clicks/thumps, etc.
• Dim: Attenuates monitor level by user-definable amount of dB (for audible convenience in studio).
• Mono: Sums the stereo output to mono (for phasing, masking issues).
• Speaker selection: Allows you to switch between different monitors (if you have them)
• Cut left, cut right: Mutes right or left monitor.
• Swap left/right: Left speaker in right speaker, right speaker in left speaker (used to check stereo imbalance)
• Source selection: Determines where the speakers get the audio (mix bus, external outputs, aux bus
o Solos
• Two types of solos:
• Destructive in-place (when one channel soloed, every other channel is cut
• Nondestructive
o PFL (takes a copy before the channel fader and pan pot, so mix levels and panning aren’t engaged
o AFL (takes a copy after the fader but before the pan, so it maintains levels, but not panning) or APL (takes a copy after the fader and pan, so both panning and levels are maintained)
• Solo safe
o Keeps a channel soloed permanently, even when other tracks soloed.
• Which solo?
o Destructive solo is favored for mixdown because when a track is soloed, the signal level remains the same as it previously was,, as opposed to nondestructive solo where the signals may drop or rise in level.
o Correct Gain Structure
• Make sure that the signal is at its optimum level so 100% of the signal is sent and received
• Given that most analog gear gives off unwanted noise, just use the channel fader, not the processor’s output. This will prevent the noise given off by the processor from being boosted.
o The Digital Console
• ADA vs. DA
• Digital consoles have fader-layer capabilities
• Allow complete control over automating any parameter
• External processing is still possible, but it is an option. On an analog console, it would be a necessity
No comments:
Post a Comment