Welcome to the Mac Streaming Masterclass
If you're streaming on a Mac and haven't enabled Metal in OBS, you're leaving serious performance on the table.
This free course will teach you:
- ✓What Metal is and why it matters for Apple Silicon
- ✓How libobs, AVFoundation, and VideoToolbox work together
- ✓How to configure OBS for maximum performance
- ✓How to stream at 1080p while recording at 4K simultaneously
About your instructor: I'm Pete, a 62-year-old streamer running a Mac Studio M2 Ultra with 128GB unified RAM. I've spent countless hours optimising OBS for macOS, and I'm sharing everything I've learned.
Estimated time: 15-20 minutes
Quick Survey
Help me understand your current setup so I can provide personalised recommendations at the end.
What is Metal?
💡 Key Insight: Metal is Apple's graphics API — it's how software talks directly to your Mac's GPU.
The Simple Explanation
Think of Metal as a translator between OBS and your Mac's powerful GPU. Without Metal, OBS uses older, slower methods to render your stream. With Metal, it speaks your GPU's native language.
Why "Experimental"?
OBS labels Metal as "experimental" because it's newer than the OpenGL renderer. But here's the truth:
- ✓Metal has been stable on Apple Silicon for years
- ✓Apple designed Apple Silicon specifically for Metal
- ✓OpenGL on macOS is deprecated — Apple stopped updating it
- ✓Metal is the future-proof choice
Performance Comparison
60%
CPU usage without Metal
15%
CPU usage with Metal
*Typical results on Apple Silicon — your mileage may vary
Your Mac Won't Explode
I've seen the fear in streamers' eyes when they see "Experimental". Let me be clear:
Enabling Metal will not damage your Mac. The worst that can happen is you switch it back off.
Understanding libobs
📚 Definition: libobs is the core library that powers OBS Studio — it's the engine under the hood.
What Does libobs Do?
When you click "Start Streaming" in OBS, libobs handles:
- →Scene composition — combining your game, webcam, overlays
- →Video encoding — compressing video for streaming
- →Audio mixing — blending mic, game audio, music
- →Output routing — sending to Twitch AND recording locally
The Architecture
Why This Matters
When you configure OBS settings, you're telling libobs which tools to use. Choose the right tools (Metal + VideoToolbox), and libobs leverages your Apple Silicon's full power.
Choose the wrong tools (OpenGL + x264), and libobs struggles with software rendering while your GPU sits idle.
🎯 Goal: Configure libobs to use hardware acceleration everywhere possible.
AVFoundation & VideoToolbox
These are Apple's media frameworks — and they're the secret sauce for efficient streaming on Mac.
AVFoundation
Apple's framework for working with audiovisual media.
- • Camera capture
- • Screen recording
- • Audio input
- • Media playback
VideoToolbox
Apple's framework for hardware-accelerated video encoding/decoding.
- • H.264 encoding (streaming)
- • HEVC/H.265 encoding (recording)
- • Hardware acceleration
- • ProRes encoding
The Encoding Choice
| Encoder | Type | Use For |
|---|---|---|
| Apple VT H264 | Hardware | Streaming ✓ |
| Apple VT HEVC | Hardware | Recording ✓ |
| x264 | Software | Avoid on Mac |
Why HEVC for Recording?
- ✓50% smaller file sizes than H.264 at same quality
- ✓Native hardware support on Apple Silicon
- ✓Perfect for 4K recording
- ✓YouTube and Twitch both accept HEVC uploads
💡 Pro Tip: Stream at 1080p (H.264 for compatibility) while recording at 4K (HEVC for quality). Your Apple Silicon can handle both simultaneously with hardware encoding.
OBS Configuration Files
OBS stores its settings in two key files. Understanding these gives you precise control.
📁 File Locations (macOS)
~/Library/Application Support/obs-studio/global.ini
~/Library/Application Support/obs-studio/basic/profiles/[ProfileName]/basic.ini
global.ini
Controls application-wide settings:
- •
Renderer— Metal or OpenGL - •
HWDecoder— Hardware decoding for media sources - •
Theme— UI appearance
basic.ini
Controls profile-specific settings:
- •
Encoder— Which encoder to use - •
Resolution— Base and output resolution - •
Bitrate— Stream and recording quality - •
Recording settings— Format, path, quality
⚠️ Warning: Always backup your existing config files before making changes. Close OBS before editing these files manually.
Key Settings for Metal Performance
# global.ini - Enable Metal renderer
[Video]
Renderer=Metal
# basic.ini - Use hardware encoding
[SimpleOutput]
StreamEncoder=com.apple.videotoolbox.videoencoder.ave.avc
RecEncoder=com.apple.videotoolbox.videoencoder.ave.hevc
✓ Good News: In the next section, I'll provide pre-configured files with detailed comments explaining every setting.
Download Your Config Pack
🎉 Apple Silicon Detected!
These configs are specifically optimised for your Mac. You'll get the full benefit of Metal and VideoToolbox hardware acceleration.
💻 Intel Mac Detected
Metal support varies by GPU on Intel Macs. These configs may still improve performance, but the biggest gains are seen on Apple Silicon. Consider this course an insight into what Apple Silicon could unlock for your streaming workflow.
🔍 Apple Silicon Not Detected
I couldn't automatically detect an Apple Silicon Mac. If you're on an Intel Mac or another platform, the information is still valuable — it shows what Apple Silicon could unlock for your streaming setup. The configs are designed for M1/M2/M3/M4 chips.
I've prepared commented configuration files that explain every setting.
Installation Instructions
- 1Close OBS completely (Cmd+Q)
- 2Backup your existing config files (rename them to .bak)
- 3Copy the downloaded files to the correct locations
- 4Open OBS — you should see Metal enabled
- 5Test your stream/recording
Quick Terminal Commands
# Backup existing configs
cd ~/Library/Application\ Support/obs-studio
cp global.ini global.ini.bak
cp basic/profiles/*/basic.ini basic/profiles/*/basic.ini.bak
🎯 Your Personalised Recommendations
Based on your survey responses, here's my analysis of your streaming setup:
Your Mac
You selected:
Metal Status
You selected:
Streaming Setup
Streaming at:
Recording Setup
Recording at:
Recommended Action:
📊 Industry Standard Reference
Professional Mac streamers typically use:
- • Stream: 1080p60 at 6000 Kbps (H.264 for compatibility)
- • Record: 4K60 locally (HEVC for smaller files, better quality)
- • Upload: 4K recording to YouTube for VODs
- • Renderer: Metal (not OpenGL)
- • Encoder: Apple VideoToolbox (not x264)
Congratulations! 🎉
You've completed the Mac Streaming Masterclass!
What You've Learned:
- ✓Metal API and why it matters for Apple Silicon
- ✓How libobs powers OBS under the hood
- ✓AVFoundation and VideoToolbox for hardware encoding
- ✓OBS configuration file structure
- ✓Optimised settings for streaming + 4K recording
- ✓Personalised recommendations for your setup
Want to Go Deeper?
Join me on Twitch where I stream using exactly this setup. Ask questions live, see the config in action, and learn advanced techniques.
Get notified when I go live
Subscriber Benefits
Twitch subscribers get access to exclusive tools:
- ★Custom stream dashboard widgets
- ★Real-time viewer count & stream timer overlays
- ★Advanced OBS configuration templates
- ★Direct support and Q&A
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