07 . Control Room to Machine Room Connections

# Control Room to Machine Room Connections ## Overview Studio A control room patchbay connects to the machine room patchbay via **DB25 snakes and XLR trunks**. This article maps where each patch point in the control room terminates in the machine room. **Related articles:** - [[01 . Studio A Patchbays]] - Control room and credenza patchbay layouts - [[Studio A Signal Flow - Circular Perspective]] - Complete signal flow from mic to DAW ## DAW Outputs (Control Room → Machine Room) ### Console Patchbay: DAW Outputs Section **Control room patch points:** - DAW Out 1-2 (Stereo mix left/right) - DAW Out 3-4 - DAW Out 5-6 - DAW Out 7-8 - DAW Out 9-10 - DAW Out 11-12 - DAW Out 13-14 - DAW Out 15-16 **Continues through:** - DAW Out 17-18 - DAW Out 19-20 - DAW Out 21-22 - DAW Out 23-24 - DAW Out 25-26 - DAW Out 27-28 - DAW Out 29-30 - DAW Out 31-32 ### Machine Room Termination **Location:** Machine room patchbay [TBD - Add photo] **Physical connection:** - DB25 snake from control room → Machine room patchbay - 8 channels per DB25 (4× DB25 snakes for 32 channels) **Machine room patch points:** - DAW Out 1-32 (top row, machine room patchbay) - Connects to: REDNET 2 inputs (analog to Dante conversion) - Or: Patch to outboard gear inputs (compressors, reverbs, etc.) **Signal flow:** ``` ProTools DAW → HDX/REDNET PCIe outputs → Control room patchbay DAW Outs → DB25 snake → Machine room patchbay → REDNET 2 inputs → Dante network ``` **Common patches:** - DAW Out 1-2 → REDNET 2 In 1-2 (main mix for monitoring) - DAW Out 3-8 → Outboard compressor inputs (parallel processing) - DAW Out 9-16 → External reverb/delay sends --- ## DAW Inputs (Machine Room → Control Room) ### Console Patchbay: DAW Inputs Section **Control room patch points:** - DAW In 1-2 (Channel strip outputs) - DAW In 3-4 - DAW In 5-6 - DAW In 7-8 - DAW In 9-10 - DAW In 11-12 - DAW In 13-14 - DAW In 15-16 **Continues through:** - DAW In 17-18 - DAW In 19-20 - DAW In 21-22 - DAW In 23-24 - DAW In 25-26 - DAW In 27-28 - DAW In 29-30 - DAW In 31-32 ### Machine Room Termination **Location:** Machine room patchbay [TBD - Add photo] **Physical connection:** - DB25 snake from machine room → Control room patchbay - 8 channels per DB25 (4× DB25 snakes for 32 channels) **Machine room patch points:** - DAW In 1-32 (bottom row, machine room patchbay) - Receives from: REDNET 2 outputs (Dante to analog conversion) - Or: Patch from outboard gear outputs (compressors, mic preamps, etc.) **Signal flow:** ``` Mic → REDNET 2 preamp → Dante network → REDNET PCIe → Machine room patchbay → DB25 snake → Control room patchbay DAW Ins → SSL channel strips → ProTools ``` **Common patches:** - REDNET 2 Out 1-16 → Machine room patchbay → DAW In 1-16 (mic inputs) - Outboard compressor outputs → Machine room patchbay → DAW In 17-24 - External reverb returns → Machine room patchbay → DAW In 25-32 --- ## Track Bus Outputs (SSL Console → Machine Room) ### Console Patchbay: Track Bus Section **Control room patch points:** - Track Bus 1-2 - Track Bus 3-4 - Track Bus 5-6 - Track Bus 7-8 - Track Bus 9-10 - Track Bus 11-12 - Track Bus 13-14 - Track Bus 15-16 **Continues through:** - Track Bus 17-18 - Track Bus 19-20 - Track Bus 21-22 - Track Bus 23-24 ### Machine Room Termination **Location:** Machine room patchbay [TBD - Add photo] **Physical connection:** - DB25 snake from control room → Machine room patchbay - 8 channels per DB25 (3× DB25 snakes for 24 channels) **Machine room patch points:** - Track Bus 1-24 (machine room patchbay) - Connects to: REDNET 2 inputs (for recording console mixes) - Or: Patch to outboard summing mixers, tape machines, etc. **Signal flow:** ``` SSL channel faders → Track Bus (stereo pairs) → Control room patchbay → DB25 snake → Machine room patchbay → REDNET 2 inputs → ProTools ``` **Common patches:** - Track Bus 1-2 → REDNET 2 In 33-34 (stereo mix from console) - Track Bus 3-4 → REDNET 2 In 35-36 (drum bus) - Track Bus 5-6 → REDNET 2 In 37-38 (instrument bus) **Use case:** - Mixing on SSL console (analog workflow) - Record console mix stems to ProTools via Track Bus → REDNET 2 → DAW - Or: Send Track Bus to outboard summing (Dangerous Music 2-Bus+) --- ## Monitor Inputs (Machine Room → Control Room) ### Console Patchbay: Monitor Inputs Section **Control room patch points:** - Monitor In 1-2 (External sources for monitoring) - Monitor In 3-4 - Monitor In 5-6 - Monitor In 7-8 - Monitor In 9-10 - Monitor In 11-12 - Monitor In 13-14 - Monitor In 15-16 ### Machine Room Termination **Location:** Machine room patchbay [TBD - Add photo] **Physical connection:** - DB25 snake from machine room → Control room patchbay - 8 channels per DB25 (2× DB25 snakes for 16 channels) **Machine room patch points:** - Monitor In 1-16 (machine room patchbay) - Receives from: REDNET 2 outputs (Dante playback sources) - Or: External playback devices (CD player, media server, etc.) **Signal flow:** ``` REDNET 2 outputs → Machine room patchbay → DB25 snake → Control room patchbay Monitor Ins → SSL monitor section → Studio monitors ``` **Common patches:** - REDNET 2 Out 33-34 → Machine room patchbay → Monitor In 1-2 (main playback) - Media server outputs → Machine room patchbay → Monitor In 3-4 - Bluetooth receiver → Machine room patchbay → Monitor In 5-6 **Use case:** - Listen to external audio sources through SSL monitor section - A/B compare mixes from different sources - Reference tracks from media server --- ## DB25 Snake Pinouts ### Standard Tascam/Yamaha Pinout **DB25 Pin → Audio Channel:** ``` Pin 1-2: Channel 1 (balanced) Pin 3-4: Channel 2 (balanced) Pin 5-6: Channel 3 (balanced) Pin 7-8: Channel 4 (balanced) Pin 9-10: Channel 5 (balanced) Pin 11-12: Channel 6 (balanced) Pin 13: Ground Pin 14-15: Channel 7 (balanced) Pin 16-17: Channel 8 (balanced) Pin 18-25: Ground ``` **Each DB25 carries 8 balanced channels** (16 conductors + ground) ### Studio A DB25 Snake Count **DAW Outputs (Control Room → Machine Room):** - 4× DB25 snakes (32 channels) **DAW Inputs (Machine Room → Control Room):** - 4× DB25 snakes (32 channels) **Track Bus Outputs (Control Room → Machine Room):** - 3× DB25 snakes (24 channels) **Monitor Inputs (Machine Room → Control Room):** - 2× DB25 snakes (16 channels) **Total:** 13× DB25 snakes between control room and machine room --- ## XLR Trunk Connections ### Studio A Wall Panels → Machine Room **Main tracking room wall panel (Mic Lines 1-16):** - 16× XLR female wall jacks - XLR trunk cable (16 channels) → Machine room patchbay - Terminates at: Machine room mic input patchbay **Iso booth wall panel (Mic Lines 17-32):** - 16× XLR female wall jacks - XLR trunk cable (16 channels) → Machine room patchbay - Terminates at: Machine room mic input patchbay ### Machine Room Mic Input Patchbay **Location:** Machine room patchbay [TBD - Add photo] **Patch points:** - Mic Line 1-32 (top row) - Connects to: REDNET 2 mic preamp inputs - Or: Patch to external mic preamps (Neve 1073, API 512c, etc.) **Signal flow:** ``` Mic → Wall panel XLR → XLR trunk → Machine room mic input patchbay → REDNET 2 mic preamps → Dante network → REDNET PCIe → ProTools ``` --- ## Machine Room Patchbay Layout (TBD) **Top section:** - DAW Outputs 1-32 (from control room) - Track Bus Outputs 1-24 (from control room) - Mic Line Inputs 1-32 (from wall panels) **Middle section:** - REDNET 2 Unit 1 Outputs 1-16 - REDNET 2 Unit 2 Outputs 17-32 - REDNET 2 Unit 3 Outputs 33-48 **Bottom section:** - DAW Inputs 1-32 (to control room) - Monitor Inputs 1-16 (to control room) - REDNET 2 Unit 1 Inputs 1-16 - REDNET 2 Unit 2 Inputs 17-32 [Add photo of machine room patchbay when available] --- ## Common Patching Scenarios ### Scenario 1: Tracking Session **Goal:** Record 16 mics → ProTools **Patches (Machine Room):** 1. Mic Line 1-16 (wall panels) → REDNET 2 Mic Inputs 1-16 2. REDNET 2 Outputs 1-16 → DAW Inputs 1-16 (to control room) **Patches (Control Room):** 1. DAW In 1-16 → SSL Channel Strips 1-16 2. SSL Channel Outputs → Track Bus 1-2 (stereo mix) 3. Track Bus 1-2 → DAW Out 1-2 (back to machine room for monitoring) **Result:** 16 mic channels routed through SSL, recorded to ProTools ### Scenario 2: Mixing with Outboard Gear **Goal:** Send ProTools tracks to external compressor, return to console **Patches (Machine Room):** 1. DAW Output 3-4 (from control room) → Distressor inputs 2. Distressor outputs → DAW Input 17-18 (to control room) **Patches (Control Room):** 1. ProTools track outputs → DAW Out 3-4 2. DAW In 17-18 → SSL Channel Strips 17-18 3. Process on console, mix to main output **Result:** Parallel compression workflow (ProTools → Outboard → Console) ### Scenario 3: External Reverb Send **Goal:** Send console channels to external reverb, return to console **Patches (Machine Room):** 1. DAW Output 9-10 (from control room) → Lexicon 480L inputs 2. Lexicon 480L outputs → Monitor Input 7-8 (to control room) **Patches (Control Room):** 1. SSL channel Aux Sends → DAW Out 9-10 (reverb send) 2. Monitor In 7-8 → SSL Aux Returns 3. Blend reverb return with dry signal **Result:** Hardware reverb on console channels --- ## Cable Management Best Practices ### DB25 Snake Labeling **Label both ends:** - Control room end: "DAW OUT 1-8 → Machine Room" - Machine room end: "DAW OUT 1-8 ← Control Room" **Use color-coded labels:** - Blue: DAW Outputs - Red: DAW Inputs - Green: Track Bus Outputs - Yellow: Monitor Inputs ### XLR Trunk Labeling **Label at wall panel:** - "Mic Line 1-16 → Machine Room" **Label at machine room patchbay:** - "Mic Line 1-16 ← Main Tracking Room" - "Mic Line 17-32 ← Iso Booth" ### Cable Routing **Keep snakes organized:** - Bundle by function (all DAW snakes together, all Track Bus snakes together) - Use cable raceways between control room and machine room - Leave service loop (extra cable length) for re-patching flexibility --- ## Troubleshooting ### No signal from machine room to control room **Check:** 1. DB25 snake properly seated at both ends 2. Correct patchbay routing (REDNET 2 outputs → DAW Inputs) 3. Dante network routing (Dante Controller shows connections) ### Intermittent crackling on specific channels **Check:** 1. DB25 pins not bent or damaged 2. XLR trunk cables not pinched or damaged 3. Patchbay jack contacts clean (use DeoxIT contact cleaner) ### Hum or ground loop on channels **Check:** 1. Ground lift switches on patchbay 2. Audio cables not running parallel to power cables 3. All equipment on same electrical phase --- ## Photos and Diagrams [Add photos when available:] - [ ] Machine room patchbay overview - [ ] Control room patchbay DAW Outputs section - [ ] Control room patchbay DAW Inputs section - [ ] DB25 snake connections at machine room - [ ] XLR trunk connections from wall panels - [ ] Cable management raceway routing [Add diagrams when available:] - [ ] Complete signal flow: Control room ↔ Machine room - [ ] DB25 pinout reference - [ ] XLR trunk routing schematic