Recording Quality & Settings

Fine-tune Clearminutes' audio capture to match your environment and hardware. Settings affect transcription accuracy, processing speed, and file size.

Sample Rate

Clearminutes records at 48 kHz (48,000 samples per second) — the professional standard for audio and Whisper transcription.

Why 48 kHz?

  • Professional standard: Matches industry recording, broadcasting, and post-production workflows
  • Whisper compatible: Optimized for Whisper's training data and accuracy
  • Headroom: Captures frequencies up to 24 kHz (human hearing tops out at ~20 kHz, so plenty of margin)
  • File size: 48 kHz = ~11.5 MB per minute of mono audio

Can I Change the Sample Rate?

No — Clearminutes locks sample rate at 48 kHz. This ensures consistent, high-quality transcription across all devices.

Sample Rate Technical Details

If you have audio at a different sample rate (e.g., 44.1 kHz from an old device), Clearminutes automatically resamples it to 48 kHz without quality loss.


Microphone Gain

Microphone gain controls the input level of your microphone before transcription. Too quiet = words missed. Too loud = audio distortion.

How to Adjust

  1. Go to Settings (⌘, on macOS, or gear icon)
  2. Navigate to Audio section
  3. Find Microphone Gain slider
  4. Adjust the percentage (0–200%)

[SCREENSHOT: Microphone Gain slider in Settings]

Optimal Level

The ideal level has:

  • Peaks (loud parts of speech) at -6 dB to -12 dB (on a dB meter, if visible)
  • Quiet speech at -20 dB to -18 dB
  • No clipping (red zones in the meter)

In practical terms, when speaking normally at your mic's distance:

  • Green meter at 50–75% of full scale = good level
  • Red meter (clipping) = too loud, lower gain
  • Grey/silent meter = too quiet, raise gain

When to Adjust Gain

SymptomSolution
Your voice is barely audible in the transcriptIncrease gain (try 120%, 140%, 160%)
Audio is clear in the recording but distortedDecrease gain (try 80%, 60%)
Keyboard typing and fan noise are loudLower gain slightly and increase noise suppression
You speak quietly or softlyIncrease gain (up to 180%) or move mic closer
You speak loudly or have a deep voiceDecrease gain (down to 60%) to avoid clipping

Gain Levels by Microphone Type

Microphone TypeTypical Gain Setting
Built-in laptop mic100–140% (built-ins are weak)
Budget USB mic80–120%
Professional USB mic60–90%
Studio condenser mic (with preamp)40–70%
Headset mic (gaming/office)80–110%
Lavalier (lapel) mic60–100%
Gain Adjustment Rule

Start at 100%. Record a 30-second test. Play it back. If too quiet, increase by +20%. If too loud, decrease by -20%. Repeat until optimal.

Testing Your Gain

  1. Set gain to your target (e.g., 100%)
  2. Start a test recording (Settings → Test Recording, or just use your next meeting)
  3. Speak at your normal distance from the mic (6–12 inches)
  4. Stop recording and play it back
  5. Listen for:
    • Clear, natural volume (not too quiet, not distorted)
    • Minimal background noise
    • No crackling or clipping sounds
  6. Adjust and repeat until satisfied

Noise Suppression

Noise suppression removes or reduces background noise: fan hum, air conditioning, keyboard clicks, car noise, etc.

Echo Suppression (Pro)

Pro Feature

Echo suppression (deduplication) removes echo and duplicate audio from recordings. Requires a Pro subscription. Upgrade →

Echo suppression detects when the same audio appears twice in your recording — common when system audio leaks into your microphone. When enabled, it removes the duplicate so your transcript doesn't contain repeated text.

  1. Go to Settings → Audio → Echo Suppression
  2. Toggle ON to enable
  3. Best used when recording system audio alongside your microphone

Enable Noise Suppression

  1. Go to Settings → Audio → Noise Suppression
  2. Toggle ON to enable
  3. Adjust the level based on your environment

When to Use

  • Quiet environment (home office): OFF or low — minimal noise to filter
  • Moderate noise (AC, fan, shared office): Medium — removes hum and distant chatter
  • Noisy environment (coffee shop, street): High — aggressive filtering to preserve speech clarity

If you're recording music or audio-heavy content, disable noise suppression to preserve all frequency content.

Trade-Offs

Higher noise suppression removes more background noise but may slightly affect speech clarity. Start with medium and adjust based on your test recordings.


Voice Activity Detection (VAD)

Pro Feature

Adjustable VAD sensitivity requires a Pro subscription. Free users use the default (medium) setting. Upgrade →

Voice Activity Detection is a critical feature that filters silence and non-speech audio before sending it to Whisper — reducing transcription time by ~70%.

How VAD Works

Raw Audio Input (48 kHz)
         ↓
Microphone Gain Applied
         ↓
Noise Suppression (optional)
         ↓
VAD Filter ← ← ← Analyzes: is this speech?
         ↓ (only sends speech)
Whisper Transcription

Key insight: VAD prevents Whisper from wasting time on silence, background noise, and non-speech audio.

VAD Sensitivity

  1. Go to Settings → Transcription → VAD Sensitivity
  2. Adjust the slider (0–10 scale, or Low/Medium/High):
    • 0 or Low — Very permissive, almost everything passes through
    • 5 or Medium — Balanced (default, recommended)
    • 10 or High — Very aggressive, only clear speech passes through

[SCREENSHOT: VAD Sensitivity slider in Settings]

Understanding VAD Impact

At VAD = 0 (Low/Permissive):

  • Everything gets sent to Whisper (audio pauses, background noise, paper shuffling, etc.)
  • Pros: No speech is accidentally filtered
  • Cons: Slower transcription (more audio to process), larger audio chunks sent to Whisper
  • Use when: Speakers have very soft voices, lots of pause-filled speech (thinking out loud), need to preserve all audio nuances

At VAD = 5 (Medium/Default):

  • Most speech passes through, obvious silence is filtered
  • Pros: Good balance — fast transcription with no speech loss
  • Cons: Very quiet speakers might be partially filtered
  • Use when: Normal meetings, clear speakers, typical office environment

At VAD = 10 (High/Aggressive):

  • Only loud, clear speech passes through
  • Pros: Fastest transcription (70% of audio filtered), best for noisy environments
  • Cons: Quiet speakers, whispers, or soft consonants might be cut off
  • Use when: Noisy environment (construction, traffic, crowded cafe), need speed over completeness

When to Adjust VAD

Lower your VAD setting if:

  • You see "whispered" or "quiet speech" being missed in the transcript
  • A speaker has a naturally soft voice
  • Your environment is very quiet (minimal background noise)
  • You're recording music, ambient sound, or audio that isn't pure speech

Raise your VAD setting if:

  • Your transcript includes background noise, chatter, or paper shuffling
  • You're in a noisy environment (coffee shop, open office, construction nearby)
  • Transcription is too slow and you want faster results
  • You want to prioritize speed over capturing every soft sound

VAD & Processing Speed

VAD dramatically affects transcription speed. With VAD set to Medium, only ~30% of audio (the speech portions) is sent to Whisper, cutting processing time by roughly 70%. Higher VAD settings filter even more non-speech audio, further reducing processing time.

Troubleshooting VAD

"Speech is being cut off or skipped":

  • Your VAD is too aggressive
  • Lower the VAD setting (move slider toward 0)
  • Some speakers might have soft voices or heavy accents — adjust for them

"Background noise appears in the transcript":

  • Your VAD is too permissive
  • Raise the VAD setting (move slider toward 10)
  • Or enable/increase noise suppression

"Transcription is very slow":

  • Your VAD might be low or off
  • Check VAD setting — ensure it's at 5 or higher
  • Or you may need GPU acceleration (see GPU Acceleration)

Use these as starting points, then adjust based on your first test recording.

Quiet Home Office

Ideal for focused work, minimal distractions:

  • Noise Suppression: OFF or Soft
  • Microphone Gain: 80–100%
  • VAD Sensitivity: Low (1–3)

Why: Quiet environments don't need suppression. Low VAD passes all speech through.

Home Office with AC/Fan

Typical home setup with environmental noise:

  • Noise Suppression: Soft
  • Microphone Gain: 90–120%
  • VAD Sensitivity: Medium (5)

Why: Soft suppression removes fan hum. Medium VAD filters obvious silence. 90–120% gain makes up for quiet home mics.

Shared Office / Open Plan

Multiple people, background chatter:

  • Noise Suppression: Moderate
  • Microphone Gain: 70–100%
  • VAD Sensitivity: Medium to High (5–7)

Why: Moderate suppression reduces chatter. Higher VAD filters more non-speech audio. Lower gain avoids picking up distant conversations.

Conference Room (in-person meeting)

Professional meeting room, multiple participants:

  • Noise Suppression: Soft (if room has AC/echo)
  • Microphone Gain: 100–140% (if using built-in mic) or 70–90% (if using USB mic)
  • VAD Sensitivity: Medium (5)

Why: Conference room mics vary widely. Soft suppression helps with room AC. Medium VAD balances speed and completeness.

Coffee Shop / Outdoor

Noisy environment:

  • Noise Suppression: Strong
  • Microphone Gain: 100–160% (if USB mic, external speakers are loud)
  • VAD Sensitivity: High (8–10)

Why: Strong suppression removes chatter and traffic. High VAD filters everything but clear speech. High gain needed because ambient noise is competing.

Podcast / Studio Recording

Professional audio content:

  • Noise Suppression: OFF
  • Microphone Gain: 70–90% (use professional mic)
  • VAD Sensitivity: Low (0–2)

Why: Studio audio is already noise-free. Suppression would harm quality. Low VAD preserves all audio nuances (breathing, slight pauses, etc.).

Remote Video Call (Zoom, Teams, etc.)

Recording yourself + call participants:

  • Noise Suppression: Soft to Moderate (depends on your environment)
  • Microphone Gain: 80–110%
  • VAD Sensitivity: Medium (5)

Why: Balanced settings for mixed audio (your voice + call audio coming through speakers). Soft-to-moderate suppression removes room noise while preserving call clarity.


Quick Setup Checklist

Before your first important meeting:

  • Set microphone gain: record 30-second test, play back, verify clear volume (not clipped)
  • Enable noise suppression if your environment has AC/fan/chatter
  • Set VAD to Medium (5) — adjust higher/lower after first test
  • Close other apps to free RAM during transcription
  • Have a USB mic handy if your environment is noisy (better than built-in)
  • Test your settings on a throwaway meeting before the real one