Audio Engineering Patterns
Technical foundations for audio production and sound design.
Signal Flow Fundamentals
The Audio Chain
Source → Processing → Summing → Output
[Mic/Synth] → [EQ/Comp/FX] → [Mix Bus] → [Master] → [Playback]
Gain Staging
Maintain optimal levels at each stage:
| Stage |
Target Level |
Headroom |
| Recording |
-18 to -12 dBFS |
12-18 dB |
| Processing |
-18 to -12 dBFS |
12-18 dB |
| Mix Bus |
-6 to -3 dBFS |
3-6 dB |
| Master |
-1 to -0.3 dBFS |
True peak limit |
Rule: If a plugin sounds bad, check your input level first.
Frequency Fundamentals
The Spectrum
| Range |
Frequency |
Character |
Instruments |
| Sub Bass |
20-60 Hz |
Felt, not heard |
Kick, bass, 808 |
| Bass |
60-250 Hz |
Foundation, warmth |
Bass, low vocals |
| Low Mids |
250-500 Hz |
Body, mud |
Guitars, vocals |
| Mids |
500-2000 Hz |
Presence, honk |
Vocals, snare |
| Upper Mids |
2-4 kHz |
Clarity, harshness |
Vocals, guitars |
| Presence |
4-6 kHz |
Definition, sibilance |
Vocals, cymbals |
| Brilliance |
6-10 kHz |
Air, shimmer |
Cymbals, strings |
| Air |
10-20 kHz |
Sparkle, hiss |
Room, breath |
EQ Patterns
Subtractive First:
- Find problem frequencies (boost, sweep, identify)
- Cut problems (narrow Q)
- Boost characteristics (wide Q)
Common Problem Areas:
| Issue |
Frequency |
Action |
| Mud |
200-400 Hz |
Cut |
| Boxiness |
400-600 Hz |
Cut |
| Honk |
800-1000 Hz |
Cut |
| Harshness |
2-4 kHz |
Cut or dip |
| Sibilance |
5-8 kHz |
De-ess or cut |
Dynamics Processing
Compression Parameters
| Parameter |
Function |
Typical Range |
| Threshold |
When compression starts |
-30 to 0 dB |
| Ratio |
How much compression |
2:1 to 20:1 |
| Attack |
How fast it engages |
0.1-100 ms |
| Release |
How fast it lets go |
50-1000 ms |
| Knee |
Soft/hard transition |
0-12 dB |
| Makeup |
Compensate for gain reduction |
As needed |
Compression Archetypes
| Style |
Attack |
Release |
Ratio |
Use |
| Transparent |
Fast |
Auto |
2-3:1 |
Vocals, mix bus |
| Punchy |
Slow |
Medium |
4-6:1 |
Drums, bass |
| Glue |
Medium |
Slow |
2-4:1 |
Mix bus, groups |
| Limiting |
Fast |
Fast |
10:1+ |
Peaks, protection |
| Pumping |
Slow |
Fast |
High |
Creative effect |
Sidechain Patterns
Trigger Source → Sidechain Input → Compressor → Target
[Kick] → [SC Input] → [Comp on Bass] → [Ducked Bass]
Use for:
- Kick/bass separation
- Vocal ducking
- Rhythmic pumping
- De-essing (high-pass SC)
Spatial Processing
Reverb Types
| Type |
Character |
Use |
| Room |
Small, tight |
Drums, guitars |
| Hall |
Large, long |
Orchestral, pads |
| Plate |
Dense, bright |
Vocals, snare |
| Chamber |
Warm, smooth |
Strings, vocals |
| Spring |
Bouncy, lo-fi |
Guitars, vintage |
| Convolution |
Realistic spaces |
Film, realism |
| Algorithmic |
Controllable |
Everything |
Reverb Parameters
| Parameter |
Effect |
| Pre-delay |
Separation from source (20-80ms typical) |
| Decay/RT60 |
Length of tail |
| Size |
Room dimensions |
| Damping |
High-frequency absorption |
| Diffusion |
Density of reflections |
| Mix/Wet |
Blend with dry signal |
Delay Patterns
| Pattern |
Timing |
Use |
| Slapback |
75-150 ms |
Vocals, rockabilly |
| Doubling |
20-50 ms |
Width, thickness |
| Rhythmic |
Tempo-synced |
Groove, production |
| Ping-pong |
L/R alternating |
Width, movement |
| Ambient |
Long, diffused |
Atmosphere |
Tempo Sync Formula:
ms = 60000 / BPM
1/4 note = 60000 / BPM
1/8 note = 30000 / BPM
1/16 note = 15000 / BPM
Dotted = value × 1.5
Triplet = value × 0.667
Mix Architecture
Bus Structure
┌─────────────┐
│ Master Bus │
└──────┬──────┘
┌───────────────┼───────────────┐
▼ ▼ ▼
┌──────────┐ ┌──────────┐ ┌──────────┐
│ Drum Bus │ │Music Bus │ │Vocal Bus │
└────┬─────┘ └────┬─────┘ └────┬─────┘
│ │ │
┌────┴────┐ ┌────┴────┐ ┌────┴────┐
│K│S│H│OH│ │B│G│K│Pd│ │Ld│BV│Fx│
└─────────┘ └─────────┘ └─────────┘
Mix in Mono First
- Get balance right in mono
- Check phase relationships
- Add stereo width last
- Always reference in mono
Static Mix Workflow
- Faders only: Get rough balance
- Pan: Create space left/right
- EQ: Carve frequency space
- Compression: Control dynamics
- Reverb/Delay: Add depth
- Automation: Movement and interest
Mastering Fundamentals
Chain Order
EQ → Compression → Saturation → Stereo Enhancement → Limiting
Target Levels
| Platform |
Target LUFS |
True Peak |
| Streaming (general) |
-14 LUFS |
-1 dB |
| Apple Music |
-16 LUFS |
-1 dB |
| YouTube |
-14 LUFS |
-1 dB |
| Club/DJ |
-6 to -9 LUFS |
-0.3 dB |
| Podcast |
-16 LUFS |
-1 dB |
| Broadcast |
-24 LUFS |
-2 dB |
Metering
| Meter Type |
Measures |
Use For |
| Peak |
Instantaneous max |
Clipping prevention |
| RMS |
Average level |
Perceived loudness |
| LUFS |
Perceptual loudness |
Streaming compliance |
| Phase |
L/R correlation |
Mono compatibility |
| Spectrum |
Frequency content |
Balance verification |
DSP Fundamentals
Basic DSP Operations
| Operation |
Effect |
| Gain |
Multiply signal amplitude |
| Sum |
Add signals together |
| Delay |
Time offset (samples) |
| Filter |
Frequency-dependent gain |
| Convolution |
Apply impulse response |
Filter Types
| Type |
Effect |
Use |
| Low-pass (LPF) |
Removes highs |
Warmth, lo-fi |
| High-pass (HPF) |
Removes lows |
Clarity, cleanup |
| Band-pass (BPF) |
Isolates range |
Radio, telephone |
| Notch |
Removes specific freq |
Feedback, hum |
| All-pass |
Phase shift only |
Phasers |
| Comb |
Periodic peaks/notches |
Flanging |
Common Sample Rates
| Rate |
Use |
Nyquist |
| 44.1 kHz |
CD, streaming |
22.05 kHz |
| 48 kHz |
Video, broadcast |
24 kHz |
| 88.2 kHz |
High-res (2× 44.1) |
44.1 kHz |
| 96 kHz |
High-res production |
48 kHz |
Sound Design Patterns
Synthesis Types
| Type |
Method |
Character |
| Subtractive |
Filter harmonics |
Classic analog |
| Additive |
Sum partials |
Precise, digital |
| FM |
Modulate frequency |
Complex, metallic |
| Wavetable |
Morph waveforms |
Evolving, digital |
| Granular |
Micro-samples |
Textural, ambient |
| Physical Modeling |
Simulate physics |
Realistic |
| Sampling |
Recorded audio |
Any source |
Layering Strategy
Layer 1: Sub (20-80 Hz) - Foundation
Layer 2: Body (100-400 Hz) - Weight
Layer 3: Character (400-2000 Hz) - Identity
Layer 4: Presence (2-6 kHz) - Cut-through
Layer 5: Air (8-16 kHz) - Sparkle
Movement Techniques
- LFO modulation (filter, pitch, amplitude)
- Envelope shaping (attack, decay curves)
- Automation (any parameter over time)
- Randomization (subtle variation)
- Sidechain (rhythmic pumping)
References
references/frequency-chart.md - Detailed frequency guide
references/plugin-chains.md - Common processing chains
references/daw-shortcuts.md - DAW workflow tips
1---2name: audio-engineering-patterns3description: Audio production concepts, DSP fundamentals, mixing/mastering techniques, and DAW workflows. Bridges modular synthesis philosophy with practical audio engineering. Triggers on audio production, mixing, sound design, DSP, or music technology requests.4license: MIT5---6
7# Audio Engineering Patterns
8
9Technical foundations for audio production and sound design.
10
11## Signal Flow Fundamentals
12
13### The Audio Chain
14
15```
16Source → Processing → Summing → Output
17
18[Mic/Synth] → [EQ/Comp/FX] → [Mix Bus] → [Master] → [Playback]
19```
20
21### Gain Staging
22
23Maintain optimal levels at each stage:
24
25| Stage | Target Level | Headroom |
26|-------|--------------|----------|
27| Recording | -18 to -12 dBFS | 12-18 dB |
28| Processing | -18 to -12 dBFS | 12-18 dB |
29| Mix Bus | -6 to -3 dBFS | 3-6 dB |
30| Master | -1 to -0.3 dBFS | True peak limit |
31
32**Rule**: If a plugin sounds bad, check your input level first.
33
34---
35
36## Frequency Fundamentals
37
38### The Spectrum
39
40| Range | Frequency | Character | Instruments |
41|-------|-----------|-----------|-------------|
42| Sub Bass | 20-60 Hz | Felt, not heard | Kick, bass, 808 |
43| Bass | 60-250 Hz | Foundation, warmth | Bass, low vocals |
44| Low Mids | 250-500 Hz | Body, mud | Guitars, vocals |
45| Mids | 500-2000 Hz | Presence, honk | Vocals, snare |
46| Upper Mids | 2-4 kHz | Clarity, harshness | Vocals, guitars |
47| Presence | 4-6 kHz | Definition, sibilance | Vocals, cymbals |
48| Brilliance | 6-10 kHz | Air, shimmer | Cymbals, strings |
49| Air | 10-20 kHz | Sparkle, hiss | Room, breath |
50
51### EQ Patterns
52
53**Subtractive First**:
541. Find problem frequencies (boost, sweep, identify)
552. Cut problems (narrow Q)
563. Boost characteristics (wide Q)
57
58**Common Problem Areas**:
59| Issue | Frequency | Action |
60|-------|-----------|--------|
61| Mud | 200-400 Hz | Cut |
62| Boxiness | 400-600 Hz | Cut |
63| Honk | 800-1000 Hz | Cut |
64| Harshness | 2-4 kHz | Cut or dip |
65| Sibilance | 5-8 kHz | De-ess or cut |
66
67---
68
69## Dynamics Processing
70
71### Compression Parameters
72
73| Parameter | Function | Typical Range |
74|-----------|----------|---------------|
75| Threshold | When compression starts | -30 to 0 dB |
76| Ratio | How much compression | 2:1 to 20:1 |
77| Attack | How fast it engages | 0.1-100 ms |
78| Release | How fast it lets go | 50-1000 ms |
79| Knee | Soft/hard transition | 0-12 dB |
80| Makeup | Compensate for gain reduction | As needed |
81
82### Compression Archetypes
83
84| Style | Attack | Release | Ratio | Use |
85|-------|--------|---------|-------|-----|
86| Transparent | Fast | Auto | 2-3:1 | Vocals, mix bus |
87| Punchy | Slow | Medium | 4-6:1 | Drums, bass |
88| Glue | Medium | Slow | 2-4:1 | Mix bus, groups |
89| Limiting | Fast | Fast | 10:1+ | Peaks, protection |
90| Pumping | Slow | Fast | High | Creative effect |
91
92### Sidechain Patterns
93
94```
95Trigger Source → Sidechain Input → Compressor → Target
96
97[Kick] → [SC Input] → [Comp on Bass] → [Ducked Bass]
98```
99
100Use for:
101- Kick/bass separation
102- Vocal ducking
103- Rhythmic pumping
104- De-essing (high-pass SC)
105
106---
107
108## Spatial Processing
109
110### Reverb Types
111
112| Type | Character | Use |
113|------|-----------|-----|
114| Room | Small, tight | Drums, guitars |
115| Hall | Large, long | Orchestral, pads |
116| Plate | Dense, bright | Vocals, snare |
117| Chamber | Warm, smooth | Strings, vocals |
118| Spring | Bouncy, lo-fi | Guitars, vintage |
119| Convolution | Realistic spaces | Film, realism |
120| Algorithmic | Controllable | Everything |
121
122### Reverb Parameters
123
124| Parameter | Effect |
125|-----------|--------|
126| Pre-delay | Separation from source (20-80ms typical) |
127| Decay/RT60 | Length of tail |
128| Size | Room dimensions |
129| Damping | High-frequency absorption |
130| Diffusion | Density of reflections |
131| Mix/Wet | Blend with dry signal |
132
133### Delay Patterns
134
135| Pattern | Timing | Use |
136|---------|--------|-----|
137| Slapback | 75-150 ms | Vocals, rockabilly |
138| Doubling | 20-50 ms | Width, thickness |
139| Rhythmic | Tempo-synced | Groove, production |
140| Ping-pong | L/R alternating | Width, movement |
141| Ambient | Long, diffused | Atmosphere |
142
143**Tempo Sync Formula**:
144```
145ms = 60000 / BPM
146
1471/4 note = 60000 / BPM
1481/8 note = 30000 / BPM
1491/16 note = 15000 / BPM
150Dotted = value × 1.5
151Triplet = value × 0.667
152```
153
154---
155
156## Mix Architecture
157
158### Bus Structure
159
160```
161 ┌─────────────┐
162 │ Master Bus │
163 └──────┬──────┘
164 ┌───────────────┼───────────────┐
165 ▼ ▼ ▼
166 ┌──────────┐ ┌──────────┐ ┌──────────┐
167 │ Drum Bus │ │Music Bus │ │Vocal Bus │
168 └────┬─────┘ └────┬─────┘ └────┬─────┘
169 │ │ │
170 ┌────┴────┐ ┌────┴────┐ ┌────┴────┐
171 │K│S│H│OH│ │B│G│K│Pd│ │Ld│BV│Fx│
172 └─────────┘ └─────────┘ └─────────┘
173```
174
175### Mix in Mono First
176
1771. Get balance right in mono
1782. Check phase relationships
1793. Add stereo width last
1804. Always reference in mono
181
182### Static Mix Workflow
183
1841. **Faders only**: Get rough balance
1852. **Pan**: Create space left/right
1863. **EQ**: Carve frequency space
1874. **Compression**: Control dynamics
1885. **Reverb/Delay**: Add depth
1896. **Automation**: Movement and interest
190
191---
192
193## Mastering Fundamentals
194
195### Chain Order
196
197```
198EQ → Compression → Saturation → Stereo Enhancement → Limiting
199```
200
201### Target Levels
202
203| Platform | Target LUFS | True Peak |
204|----------|-------------|-----------|
205| Streaming (general) | -14 LUFS | -1 dB |
206| Apple Music | -16 LUFS | -1 dB |
207| YouTube | -14 LUFS | -1 dB |
208| Club/DJ | -6 to -9 LUFS | -0.3 dB |
209| Podcast | -16 LUFS | -1 dB |
210| Broadcast | -24 LUFS | -2 dB |
211
212### Metering
213
214| Meter Type | Measures | Use For |
215|------------|----------|---------|
216| Peak | Instantaneous max | Clipping prevention |
217| RMS | Average level | Perceived loudness |
218| LUFS | Perceptual loudness | Streaming compliance |
219| Phase | L/R correlation | Mono compatibility |
220| Spectrum | Frequency content | Balance verification |
221
222---
223
224## DSP Fundamentals
225
226### Basic DSP Operations
227
228| Operation | Effect |
229|-----------|--------|
230| Gain | Multiply signal amplitude |
231| Sum | Add signals together |
232| Delay | Time offset (samples) |
233| Filter | Frequency-dependent gain |
234| Convolution | Apply impulse response |
235
236### Filter Types
237
238| Type | Effect | Use |
239|------|--------|-----|
240| Low-pass (LPF) | Removes highs | Warmth, lo-fi |
241| High-pass (HPF) | Removes lows | Clarity, cleanup |
242| Band-pass (BPF) | Isolates range | Radio, telephone |
243| Notch | Removes specific freq | Feedback, hum |
244| All-pass | Phase shift only | Phasers |
245| Comb | Periodic peaks/notches | Flanging |
246
247### Common Sample Rates
248
249| Rate | Use | Nyquist |
250|------|-----|---------|
251| 44.1 kHz | CD, streaming | 22.05 kHz |
252| 48 kHz | Video, broadcast | 24 kHz |
253| 88.2 kHz | High-res (2× 44.1) | 44.1 kHz |
254| 96 kHz | High-res production | 48 kHz |
255
256---
257
258## Sound Design Patterns
259
260### Synthesis Types
261
262| Type | Method | Character |
263|------|--------|-----------|
264| Subtractive | Filter harmonics | Classic analog |
265| Additive | Sum partials | Precise, digital |
266| FM | Modulate frequency | Complex, metallic |
267| Wavetable | Morph waveforms | Evolving, digital |
268| Granular | Micro-samples | Textural, ambient |
269| Physical Modeling | Simulate physics | Realistic |
270| Sampling | Recorded audio | Any source |
271
272### Layering Strategy
273
274```
275Layer 1: Sub (20-80 Hz) - Foundation
276Layer 2: Body (100-400 Hz) - Weight
277Layer 3: Character (400-2000 Hz) - Identity
278Layer 4: Presence (2-6 kHz) - Cut-through
279Layer 5: Air (8-16 kHz) - Sparkle
280```
281
282### Movement Techniques
283
284- LFO modulation (filter, pitch, amplitude)
285- Envelope shaping (attack, decay curves)
286- Automation (any parameter over time)
287- Randomization (subtle variation)
288- Sidechain (rhythmic pumping)
289
290---
291
292## References
293
294- `references/frequency-chart.md` - Detailed frequency guide
295- `references/plugin-chains.md` - Common processing chains
296- `references/daw-shortcuts.md` - DAW workflow tips