Every recording session has that moment: you're watching a stream, listening to a podcast, or in a call — and something incredible happens. You scramble to hit record, but it's already over. The audio is gone. You can't get it back.
Retro-Rec solves this at the infrastructure level. Instead of capturing audio only when you tell it to, SampleGrab continuously buffers the last N minutes of audio in memory at all times. When you press Capture, the buffer is included in the recording — going back as far as your selected buffer window.
How the buffer works
The buffer is a rolling window — it constantly overwrites its oldest content with new audio. Think of it as a circular tape machine that's always running. The moment you press Capture, the machine locks in what it has and keeps recording forward from that point.
Choosing a buffer size
Lowest memory impact. Good for catching a punchline, a stat, or a short sound effect that just played.
The sweet spot for most use cases. One minute of audio covers most conversations, highlights, and clips.
Capture an entire segment retroactively. Uses the most memory but essential for long-form content monitoring.
The 5-minute buffer keeps a significant chunk of uncompressed audio in RAM. On systems with less than 4GB of free memory, stick to 30s or 60s to avoid any performance impact on the tab you're recording.
Enabling Retro-Rec
At the bottom of the SampleGrab popup you'll find the RETRO REC control bar. Click the power button to activate it, then select your buffer window: 30s, 60s, or 5m.
Once enabled, the power button glows and SampleGrab begins buffering immediately. You don't need to be actively recording — the buffer runs as long as SampleGrab has access to the tab's audio.
Enable Retro-Rec before you start watching. Leave it running in the background. When something worth saving happens, hit CAPTURE — and you'll have everything going back as far as your buffer window, plus everything going forward until you stop.
Retro-Rec vs. regular recording
| Feature | Regular recording | Retro-Rec |
|---|---|---|
| Captures after pressing record | ✓ Yes | ✓ Yes |
| Captures before pressing record | ✗ No | ✓ Yes (up to buffer length) |
| Always-on background capture | ✗ No | ✓ Yes |
| Memory overhead | None (until recording) | Proportional to buffer size |
| Best for | Planned recordings | Spontaneous moments |
Use cases worth knowing
Live streams and sports: You're watching a live match and a highlight happens. With a 5-minute buffer you can capture the whole sequence leading up to it retroactively — goals, reactions, commentary and all.
Podcasts and interviews: Someone says something unexpectedly interesting. Hit Capture, and your clip will include the preceding minute of context that makes the quote make sense.
Music discovery: You're using a streaming service or radio player and a track comes on that you want to sample. With a 60s buffer, even if you only noticed 20 seconds in, you can still capture the beginning.
Meetings and calls: A colleague says something that needs to be documented. Retro-Rec means you don't need to be recording the entire meeting proactively — just capture when it matters.
The buffer only captures audio from the specific tab SampleGrab is attached to. It doesn't capture audio from other tabs, your microphone, or system sounds unless those are coming through the same tab.