Microphone Audio Samples for STT Evaluation
February 4, 2026 · View on GitHub
Reports
| Report | Format | Description |
|---|---|---|
| Benchmark Report | Complete analysis with rankings, correlations, and recommendations | |
| Benchmark Report (source) | Typst | Editable source file |
Releases
| Date | Release | Description |
|---|---|---|
| 2025-02-04 | Current | 17 samples, 12 microphones (added EMEET, Sony DVR) |
| 2025-12-23 | v2025.12.23 | Initial benchmark: 15 samples, 10 microphones |
Key Takeaway
Microphone quality matters less than environment for STT accuracy. In this benchmark of 15 recordings across 10 microphones, most devices clustered within a narrow 4-6% Word Error Rate (WER) range. The biggest differentiator wasn't price or specifications—a $30 USB gooseneck mic matched or beat $150+ headsets. The same smartphone showed 50% higher error rates in a noisy market compared to a quiet room. For speech-to-text work, any decent microphone in a quiet space outperforms expensive gear in poor acoustic conditions.
All audio samples are untreated raw recordings—no noise reduction, normalization, or post-processing applied.
Results (Single Transcription)
A benchmark comparing how different microphones affect speech-to-text (STT) accuracy. All samples use the same ~2-minute reference text about coffee history, recorded in a consistent home office environment.
Purpose
This repository evaluates which microphones produce the best results for speech-to-text transcription by testing:
- Word Error Rate (WER) - Accuracy of transcription against ground truth
- Audio Quality Score - Technical quality metrics relevant to voice/STT applications
Methodology
All transcriptions performed using OpenAI Whisper API (whisper-1) in a single evaluation session on 2025-12-23 to ensure methodological consistency.
- Reference Text: 315 words about coffee history (~2 minutes spoken)
- Recording Environment: Home office, quiet acoustic conditions
- Recording Software: Audacity (default for most samples)
- Transcription: OpenAI Whisper API (whisper-1)
- Metrics: Word Error Rate (WER), Character Error Rate (CER), audio analysis via ffprobe
Microphones Tested
| ID | Microphone | Type | Category | Price (USD) | Notes |
|---|---|---|---|---|---|
| 1 | UGreen CM564 | USB Gooseneck | Desktop | ~$18 | 30cm distance |
| 2 | Samson Q2U | Dynamic USB/XLR | Desktop | ~$70 | 30cm distance |
| 3 | Logitech H390 | USB Headset | Headset | ~$30 | Overhead mic |
| 4 | OnePlus Nord 3 5G | Smartphone built-in | Mobile | — | ASR HQ recording |
| 5 | OnePlus Nord 3 5G | Smartphone built-in | Mobile | — | Voicenotes.com (MP3) |
| 6 | Audio-Technica ATR4697 | Boundary Mic | Desktop | ~$45 | 30cm distance |
| 7 | Audio-Technica ATR4697 | Boundary Mic | Desktop | ~$45 | 80cm (long throw) |
| 8 | Jabra Speak 510 | USB Speakerphone | Desktop | ~$110 | Conference device |
| 9 | Logitech C925e | Webcam built-in | Desktop | ~$75 | 30cm distance |
| 10 | Maono Elf | Lavalier | Lavalier | ~$25 | Wired lav |
| 11 | Yealink BH72 | Wireless Headset | Headset | ~$160 | BT51 dongle |
| 12 | Yealink BH72 | Wireless Headset | Headset | ~$160 | TP-Link UB500 |
| 13 | Audio-Technica ATR4750-USB | Condenser Gooseneck | Desktop | ~$55 | Omnidirectional |
| 14 | OnePlus Nord 3 5G | Smartphone built-in | Mobile | — | Noisy (Mahane Yehuda) |
| 15 | OnePlus Nord 3 5G | Smartphone built-in | Mobile | — | Quiet (home office) |
| 16 | EMEET Conference | USB Speakerphone | Desktop | ~$40 | Conference speakerphone |
| 17 | Sony ICD-UX570 | Digital Voice Recorder | Portable | ~$100 | Standalone DVR (MP3) |
STT Evaluation Results
Word Error Rate (WER) - Lower is Better
| Rank | ID | Microphone | Category | WER |
|---|---|---|---|---|
| 1 | 15 | OnePlus Nord 3 5G (quiet) | Mobile | 4.13% |
| 2 | 1 | UGreen CM564 | Desktop | 4.44% |
| 3 | 7 | Audio-Technica ATR4697 (80cm) | Desktop | 4.76% |
| 4 | 16 | EMEET Conference | Desktop | 5.08% |
| 5 | 2 | Samson Q2U | Desktop | 5.40% |
| 5 | 5 | OnePlus Nord 3 5G (MP3) | Mobile | 5.40% |
| 5 | 6 | Audio-Technica ATR4697 (30cm) | Desktop | 5.40% |
| 5 | 8 | Jabra Speak 510 | Desktop | 5.40% |
| 5 | 9 | Logitech C925e | Desktop | 5.40% |
| 5 | 10 | Maono Elf | Lavalier | 5.40% |
| 11 | 3 | Logitech H390 | Headset | 5.71% |
| 11 | 4 | OnePlus Nord 3 5G (HQ) | Mobile | 5.71% |
| 13 | 11 | Yealink BH72 (dongle) | Headset | 6.03% |
| 13 | 12 | Yealink BH72 (BT) | Headset | 6.03% |
| 13 | 14 | OnePlus Nord 3 5G (noisy) | Mobile | 6.03% |
| 13 | 17 | Sony ICD-UX570 | Portable | 6.03% |
| 17 | 13 | Audio-Technica ATR4750-USB | Desktop | 6.35% |
Audio Quality Scores - Higher is Better
Quality score (0-100) based on technical audio metrics including SNR, dynamic range, clipping, and RMS levels.
| Rank | Microphone | Category | Quality Score |
|---|---|---|---|
| 1 | OnePlus Nord 3 5G (noisy) | Mobile | 89.0 |
| 2 | Yealink BH72 (dongle) | Headset | 85.0 |
| 2 | Yealink BH72 (BT) | Headset | 85.0 |
| 4 | OnePlus Nord 3 5G (HQ) | Mobile | 84.5 |
| 5 | OnePlus Nord 3 5G (MP3) | Mobile | 83.0 |
| 6 | Samson Q2U | Desktop | 80.0 |
| 6 | Jabra Speak 510 | Desktop | 80.0 |
Category Summary
| Category | Avg Quality Score | Avg WER | Best Performer |
|---|---|---|---|
| Desktop | 72.1 | 5.28% | UGreen CM564 (4.44%) |
| Mobile | 84.0 | 5.32% | OnePlus Nord 3 quiet (4.13%) |
| Lavalier | 75.0 | 5.40% | Maono Elf |
| Headset | 81.3 | 5.93% | Logitech H390 (5.71%) |
| Portable | 78.0 | 6.03% | Sony ICD-UX570 |
Average WER by Microphone Type
| Rank | Microphone Type | Avg WER | Samples | Avg Price |
|---|---|---|---|---|
| 1 | USB Gooseneck | 4.44% | 1 | ~$18 |
| 2 | Boundary Microphone | 5.08% | 2 | ~$45 |
| 3 | USB Speakerphone | 5.24% | 2 | ~$75 |
| 4 | Smartphone built-in | 5.32% | 4 | — |
| 5 | Dynamic USB/XLR | 5.40% | 1 | ~$70 |
| 5 | Webcam built-in | 5.40% | 1 | ~$75 |
| 5 | Lavalier | 5.40% | 1 | ~$25 |
| 8 | USB Headset | 5.71% | 1 | ~$30 |
| 9 | Wireless Headset | 6.03% | 2 | ~$160 |
| 9 | Digital Voice Recorder | 6.03% | 1 | ~$100 |
| 11 | Condenser Gooseneck | 6.35% | 1 | ~$55 |
Key Findings
-
Best for STT Accuracy: The OnePlus Nord 3 in a quiet environment achieved the lowest WER (4.13%), followed closely by the UGreen CM564 gooseneck (4.44%).
-
Audio Quality vs WER Mismatch: Higher audio quality scores don't directly correlate with better STT accuracy. The Yealink BH72 had the highest quality score (85) but only mid-range WER (6.03%).
-
Environment Matters More Than Equipment: The same OnePlus phone showed 4.13% WER in a quiet environment vs 6.03% in the noisy Mahane Yehuda market - a significant difference.
-
Distance Affects Results: The Audio-Technica ATR4697 boundary mic at 80cm outperformed the same mic at 30cm (4.76% vs 5.40%), possibly due to reduced proximity effects.
-
Bluetooth Consistency: Unlike some previous tests, both Yealink BH72 connection methods (dedicated dongle vs generic Bluetooth adapter) performed identically (6.03% WER).
-
Most Microphones Perform Similarly: The majority of microphones clustered around 5.40% WER, suggesting that for typical quiet office use, microphone choice has less impact than environmental factors.
Price vs Accuracy Analysis
Counter-intuitive finding: More expensive microphones showed worse STT accuracy.
| Price Tier | Samples | Avg WER | Best Performer |
|---|---|---|---|
| Budget ($0-30) | 3 | 5.19% | UGreen CM564 (4.44%) |
| Mid-range ($31-80) | 6 | 5.33% | EMEET Conference (5.08%) |
| Premium ($80+) | 4 | 5.87% | Jabra Speak 510 (5.40%) |
Correlation Statistics (phone samples excluded, n=13):
- Pearson r = 0.578 (moderate positive correlation—higher price, higher error rate)
- p-value = 0.039 (statistically significant at α=0.05)
This is now a statistically significant finding: more expensive microphones tend to have worse STT accuracy. The $18 UGreen gooseneck outperforms the $160 Yealink headset. The $40 EMEET conference speakerphone beats the $110 Jabra Speak 510.
Conference Speakerphone Head-to-Head
| Model | Price | WER | Value |
|---|---|---|---|
| EMEET Conference | $40 | 5.08% | Best value |
| Jabra Speak 510 | $110 | 5.40% | 2.75× more expensive, worse accuracy |
Spectral Analysis
Spectrograms were generated for all 15 samples to visualize frequency characteristics and explore correlations with WER. All recordings are untreated raw audio—no noise reduction, normalization, or processing applied.
Audio Feature Correlations
| Feature | Correlation with WER | Interpretation |
|---|---|---|
| Spectral Bandwidth | r = -0.516 (p=0.049) | Wider bandwidth → lower error rate |
| Harmonic Ratio | r = -0.443 (p=0.098) | Cleaner voice signal → lower error rate |
| Speech Clarity Ratio | r = +0.393 (p=0.147) | Complex relationship |
Individual spectrograms for each microphone are available in the spectrograms/ directory, showing:
- Full frequency spectrum (0-8kHz, speech range)
- Mel spectrogram (perceptual frequency scale)
- Spectral features over time (centroid, rolloff)
- Key audio metrics (harmonic ratio, speech band energy)
Repository Structure
.
├── samples/ # Audio recordings (WAV/MP3)
├── text/ # Reference text (coffee.txt)
├── metadata.json # Recording metadata for each sample
├── evaluation_results.json # Full evaluation data
├── evaluate.py # Evaluation script
├── update_analysis.py # Spectrogram & audio feature analysis
├── update_price_analysis.py # Price vs WER correlation analysis
├── generate_type_comparison.py # Microphone type comparison charts
├── reports/ # Generated reports
│ ├── microphone-stt-benchmark.pdf # Main benchmark report
│ └── microphone-stt-benchmark.typ # Typst source
├── device-images/
│ ├── originals/ # Microphone product photos
│ └── composites/ # Generated graphics
├── spectrograms/ # Audio analysis outputs
│ ├── spectrogram_*.png # Individual spectrograms per sample
│ ├── spectrograms_collection.pdf # All spectrograms in PDF (landscape)
│ ├── spectrograms_ranked_by_wer.png
│ ├── type_comparison_analysis.png
│ ├── correlation_analysis.png
│ ├── price_vs_wer_analysis.png
│ ├── analysis_report.md # Detailed analysis findings
│ └── audio_features.csv # Extracted features data
└── microphones/ # Detailed microphone documentation
Downloads
- Benchmark Report (PDF) - Complete benchmark report with rankings and analysis
- Benchmark Report (Typst) - Editable source file
- Spectrograms PDF Collection - All spectrograms in landscape format
- Spectrograms Grid - All 17 spectrograms ranked by WER
- Type Comparison - Microphone type head-to-head analysis
- WER by Type Ranking - Average WER by microphone type (sorted best to worst)
- Price Correlation Chart - Price vs accuracy analysis
- Audio Feature Correlations - Feature correlation scatter plots
- Analysis Report - Detailed audio feature analysis findings
- Audio Features CSV - Raw extracted audio features data
License
Audio samples and evaluation data provided for research and comparison purposes.