Difference between revisions of "THD Sweep Measurement"
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== | == THD SWEEP MEASUREMENT - USER GUIDE == | ||
''Master the art of measuring Total Harmonic Distortion with style'' | |||
__TOC__ | |||
=== | {| style="width:100%; background: linear-gradient(135deg, #667eea 0%, #764ba2 100%); color: white; padding: 30px; border-radius: 10px; margin: 20px 0; text-align: center;" | ||
|- | |||
| style="font-size: 2.5em; font-weight: bold;" | π΅ THD SWEEP MEASUREMENT | |||
|- | |||
| style="font-size: 1.2em; opacity: 0.95;" | Professional Acoustic Testing Made Simple | |||
|} | |||
Β | |||
--- | |||
Β | |||
== β‘ QUICK START - 30 SECONDS == | |||
Β | |||
{| style="width: 100%; border-collapse: collapse; margin: 20px 0;" | |||
|- | |||
| style="background: #f0f4ff; padding: 20px; border-left: 5px solid #667eea; font-weight: bold; width: 50%;" | STEP | |||
| style="background: #f0f4ff; padding: 20px; border-left: 5px solid #667eea; font-weight: bold; width: 50%;" | ACTION | |||
|- | |||
| style="padding: 15px; background: #fafbff;" | 1οΈβ£ Launch | |||
| style="padding: 15px; background: #fafbff;" | Double-click <code>Lancer_THD.bat</code> | |||
|- | |||
| style="padding: 15px; background: white;" | 2οΈβ£ Connect | |||
| style="padding: 15px; background: white;" | Check top right: <span style="color: green; font-weight: bold;">β Connected</span> | |||
|- | |||
| style="padding: 15px; background: #fafbff;" | 3οΈβ£ Start | |||
| style="padding: 15px; background: #fafbff;" | Click green <code>βΆ START</code> button | |||
|- | |||
| style="padding: 15px; background: white;" | 4οΈβ£ Monitor | |||
| style="padding: 15px; background: white;" | Watch 4 metrics update live | |||
|- | |||
| style="padding: 15px; background: #fafbff;" | 5οΈβ£ Stop | |||
| style="padding: 15px; background: #fafbff;" | Click red <code>β STOP</code> button | |||
|} | |||
<div style="background: #e8f5e9; border-left: 5px solid #4caf50; padding: 20px; margin: 20px 0; border-radius: 5px;"> | |||
β
'''That's it!''' Your first THD measurement is complete. You're now a certified acoustic engineer. (Not really, but it feels good.) | |||
</div> | |||
--- | |||
== | == π YOUR INTERFACE - WHAT YOU SEE == | ||
=== π’ Status Indicators (Top Right) === | |||
# | {| style="width: 100%; margin: 15px 0; border-collapse: collapse;" | ||
# | |- | ||
# | | style="width: 50%; background: #e8f5e9; padding: 15px; border: 1px solid #c8e6c9; font-weight: bold;" | INDICATOR | ||
# | | style="width: 50%; background: #e8f5e9; padding: 15px; border: 1px solid #c8e6c9; font-weight: bold;" | MEANING | ||
# | |- | ||
# | | style="padding: 12px; background: white; border: 1px solid #c8e6c9;" | <span style="color: green; font-size: 1.2em;">β</span> NVGate Connected | ||
# | | style="padding: 12px; background: white; border: 1px solid #c8e6c9;" | Perfect! NVGate is ready to rock πΈ | ||
# | |- | ||
| style="padding: 12px; background: white; border: 1px solid #c8e6c9;" | <span style="color: red; font-size: 1.2em;">β</span> NVGate Disconnected | |||
| style="padding: 12px; background: white; border: 1px solid #c8e6c9;" | Oops! Start NVGate first π€ | |||
|- | |||
| style="padding: 12px; background: white; border: 1px solid #c8e6c9;" | <span style="color: green; font-size: 1.2em;">β</span> Measurement Running | |||
| style="padding: 12px; background: white; border: 1px solid #c8e6c9;" | Data is flowing! π | |||
|- | |||
| style="padding: 12px; background: white; border: 1px solid #c8e6c9;" | <span style="color: #999; font-size: 1.2em;">β</span> Measurement Stopped | |||
| style="padding: 12px; background: white; border: 1px solid #c8e6c9;" | Ready for the next round βΈοΈ | |||
|} | |||
=== | === π Four Metric Cards === | ||
The | The heart of the interface. These four numbers tell the whole story: | ||
{| | {| style="width: 100%; margin: 20px 0; border-collapse: collapse;" | ||
|- | |- | ||
| style="background: linear-gradient(135deg, #667eea, #764ba2); color: white; padding: 25px; text-align: center; font-weight: bold; width: 25%; border: none;" | π<br/>THD (dB) | |||
| style="background: linear-gradient(135deg, #667eea, #764ba2); color: white; padding: 25px; text-align: center; font-weight: bold; width: 25%; border: none;" | π<br/>THD (%) | |||
| style="background: linear-gradient(135deg, #667eea, #764ba2); color: white; padding: 25px; text-align: center; font-weight: bold; width: 25%; border: none;" | π‘<br/>Frequency | |||
| style="background: linear-gradient(135deg, #667eea, #764ba2); color: white; padding: 25px; text-align: center; font-weight: bold; width: 25%; border: none;" | β‘<br/>Fundamental | |||
|- | |- | ||
| | | style="background: #f5f5f5; padding: 20px; text-align: center; border: 1px solid #ddd;" | Harmonic distortion (log scale) | ||
| style="background: #f5f5f5; padding: 20px; text-align: center; border: 1px solid #ddd;" | Harmonic distortion (%) | |||
| style="background: #f5f5f5; padding: 20px; text-align: center; border: 1px solid #ddd;" | Current sweep point | |||
| style="background: #f5f5f5; padding: 20px; text-align: center; border: 1px solid #ddd;" | Signal strength | |||
|- | |- | ||
| | | style="background: white; padding: 20px; text-align: center; border: 1px solid #ddd; font-family: monospace; font-weight: bold; color: #667eea;" | +5.42 dB | ||
| style="background: white; padding: 20px; text-align: center; border: 1px solid #ddd; font-family: monospace; font-weight: bold; color: #667eea;" | 58.294 % | |||
| style="background: white; padding: 20px; text-align: center; border: 1px solid #ddd; font-family: monospace; font-weight: bold; color: #667eea;" | 1234.56 Hz | |||
| style="background: white; padding: 20px; text-align: center; border: 1px solid #ddd; font-family: monospace; font-weight: bold; color: #667eea;" | 5.0e-01 V | |||
|} | |||
Β | |||
=== π¬ Log Console (Bottom) === | |||
Β | |||
Real-time messages with color coding: | |||
Β | |||
{| style="width: 100%; border-collapse: collapse; margin: 15px 0;" | |||
|- | |||
| style="width: 20%; background: #e8f5e9; padding: 10px; font-weight: bold;" | π’ GREEN | |||
| style="width: 80%; background: #e8f5e9; padding: 10px;" | Everything OK - measurement working perfectly | |||
|- | |- | ||
| | | style="width: 20%; background: #ffebee; padding: 10px; font-weight: bold;" | π΄ RED | ||
| style="width: 80%; background: #ffebee; padding: 10px;" | Error occurred - something needs attention | |||
|- | |- | ||
| ''' | | style="width: 20%; background: #e3f2fd; padding: 10px; font-weight: bold;" | π΅ BLUE | ||
| style="width: 80%; background: #e3f2fd; padding: 10px;" | Information - status updates and details | |||
|} | |||
Β | |||
--- | |||
Β | |||
== π― UNDERSTANDING YOUR RESULTS == | |||
Β | |||
=== THD (%) - The Easy Number === | |||
Β | |||
<div style="background: linear-gradient(135deg, #c8e6c9, #a5d6a7); padding: 25px; border-radius: 10px; margin: 20px 0; color: #1b5e20;"> | |||
Β | |||
'''What is it?''' Percentage of unwanted harmonics in your signal. | |||
Β | |||
Think of it this way: | |||
* THD 5% = 95% pure signal, 5% noise | |||
* THD 20% = 80% pure signal, 20% noise | |||
Β | |||
'''The Quality Scale:''' | |||
Β | |||
{| style="width: 100%; background: white; border-collapse: collapse; margin-top: 15px;" | |||
|- | |||
| style="padding: 12px; background: #fff3e0; border: 1px solid #ffe0b2; font-weight: bold;" | π 1% - 5% | |||
| style="padding: 12px; background: #fff3e0; border: 1px solid #ffe0b2;" | Excellent - Professional grade equipment | |||
|- | |||
| style="padding: 12px; background: #e8f5e9; border: 1px solid #c8e6c9; font-weight: bold;" | β
5% - 15% | |||
| style="padding: 12px; background: #e8f5e9; border: 1px solid #c8e6c9;" | Good - Solid speaker performance | |||
|- | |||
| style="padding: 12px; background: #fff9c4; border: 1px solid #fff59d; font-weight: bold;" | β οΈ 15% - 30% | |||
| style="padding: 12px; background: #fff9c4; border: 1px solid #fff59d;" | Acceptable - Consumer level equipment | |||
|- | |||
| style="padding: 12px; background: #ffebee; border: 1px solid #ffcdd2; font-weight: bold;" | β > 30% | |||
| style="padding: 12px; background: #ffebee; border: 1px solid #ffcdd2;" | Poor - Time for an upgrade π οΈ | |||
|} | |||
Β | |||
</div> | |||
Β | |||
=== THD (dB) - The Technical Number === | |||
Β | |||
<div style="background: linear-gradient(135deg, #bbdefb, #90caf9); padding: 25px; border-radius: 10px; margin: 20px 0; color: #0d47a1;"> | |||
Β | |||
Same measurement as THD (%) but in decibels (logarithmic scale). | |||
Β | |||
'''Quick Conversion Chart:''' | |||
Β | |||
{| style="width: 100%; background: white; border-collapse: collapse; margin-top: 15px;" | |||
|- | |||
| style="padding: 12px; background: #f5f5f5; border: 1px solid #e0e0e0; font-weight: bold; text-align: center;" | THD % | |||
| style="padding: 12px; background: #f5f5f5; border: 1px solid #e0e0e0; font-weight: bold; text-align: center;" | THD dB | |||
| style="padding: 12px; background: #f5f5f5; border: 1px solid #e0e0e0; font-weight: bold; text-align: center;" | Quality | |||
|- | |||
| style="padding: 12px; border: 1px solid #e0e0e0; text-align: center;" | 1% | |||
| style="padding: 12px; border: 1px solid #e0e0e0; text-align: center; font-family: monospace;" | -40 dB | |||
| style="padding: 12px; border: 1px solid #e0e0e0; text-align: center;" | π Perfect | |||
|- | |||
| style="padding: 12px; border: 1px solid #e0e0e0; text-align: center;" | 3% | |||
| style="padding: 12px; border: 1px solid #e0e0e0; text-align: center; font-family: monospace;" | -30 dB | |||
| style="padding: 12px; border: 1px solid #e0e0e0; text-align: center;" | β
Great | |||
|- | |||
| style="padding: 12px; border: 1px solid #e0e0e0; text-align: center;" | 10% | |||
| style="padding: 12px; border: 1px solid #e0e0e0; text-align: center; font-family: monospace;" | -20 dB | |||
| style="padding: 12px; border: 1px solid #e0e0e0; text-align: center;" | β
Good | |||
|- | |||
| style="padding: 12px; border: 1px solid #e0e0e0; text-align: center;" | 30% | |||
| style="padding: 12px; border: 1px solid #e0e0e0; text-align: center; font-family: monospace;" | -10 dB | |||
| style="padding: 12px; border: 1px solid #e0e0e0; text-align: center;" | β οΈ Poor | |||
|} | |||
Β | |||
</div> | |||
Β | |||
--- | |||
Β | |||
== π TYPICAL MEASUREMENT WORKFLOW == | |||
Β | |||
=== Pre-Measurement Checklist === | |||
Β | |||
<div style="background: #fff3e0; border-left: 5px solid #ff9800; padding: 20px; margin: 20px 0; border-radius: 5px;"> | |||
Before you start, verify: | |||
* β NVGate is open and ready | |||
* β Sweep is configured (e.g., 10 Hz β 20 kHz) | |||
* β FFT traces are visible on screen | |||
* β Sine generator is active | |||
* β Speaker is connected and working | |||
</div> | |||
Β | |||
=== Step-by-Step Workflow === | |||
Β | |||
{| style="width: 100%; border-collapse: collapse; margin: 20px 0; background: white;" | |||
|- | |||
| style="background: #667eea; color: white; padding: 15px; font-weight: bold; width: 5%; text-align: center;" | | |||
| style="background: #667eea; color: white; padding: 15px; font-weight: bold; width: 25%;" | PHASE | |||
| style="background: #667eea; color: white; padding: 15px; font-weight: bold; width: 70%;" | WHAT TO DO | |||
|- | |||
| style="background: #f5f5f5; padding: 15px; text-align: center; font-size: 2em;" | 1οΈβ£ | |||
| style="background: #f5f5f5; padding: 15px; font-weight: bold;" | Prepare | |||
| style="background: #f5f5f5; padding: 15px;" | Open NVGate β Set sweep β Verify FFT visible | |||
|- | |||
| style="background: white; padding: 15px; text-align: center; font-size: 2em;" | 2οΈβ£ | |||
| style="background: white; padding: 15px; font-weight: bold;" | Launch App | |||
| style="background: white; padding: 15px;" | Double-click Lancer_THD.bat β Check Connected status | |||
|- | |||
| style="background: #f5f5f5; padding: 15px; text-align: center; font-size: 2em;" | 3οΈβ£ | |||
| style="background: #f5f5f5; padding: 15px; font-weight: bold;" | Start | |||
| style="background: #f5f5f5; padding: 15px;" | Click βΆ START β Watch log for "Starting THD Measurement" | |||
|- | |||
| style="background: white; padding: 15px; text-align: center; font-size: 2em;" | 4οΈβ£ | |||
| style="background: white; padding: 15px; font-weight: bold;" | Monitor | |||
| style="background: white; padding: 15px;" | Watch metrics update β Frequency should increase β THD should be stable | |||
|- | |||
| style="background: #f5f5f5; padding: 15px; text-align: center; font-size: 2em;" | 5οΈβ£ | |||
| style="background: #f5f5f5; padding: 15px; font-weight: bold;" | Stop | |||
| style="background: #f5f5f5; padding: 15px;" | Click β STOP β Watch for "Measurement ended" β Note final values | |||
|} | |||
Β | |||
--- | |||
Β | |||
== βοΈ CONFIGURATION == | |||
Β | |||
=== When Do I Need to Change This? === | |||
Β | |||
<div style="background: #e3f2fd; border-left: 5px solid #2196f3; padding: 20px; margin: 20px 0; border-radius: 5px;"> | |||
Β | |||
'''Honest answer: Almost never.''' | |||
Β | |||
The default settings work for 95% of users. Only change if your NVGate project has: | |||
* Different window names | |||
* Different marker numbers | |||
* Different DC input addresses | |||
Β | |||
If you're not sure β Don't change anything. It works. Trust it. | |||
Β | |||
</div> | |||
Β | |||
=== How to Access Configuration === | |||
Β | |||
Click on '''βΆ Configuration''' (section expands) | |||
Β | |||
=== Important Settings === | |||
Β | |||
{| style="width: 100%; border-collapse: collapse; margin: 15px 0;" | |||
|- | |- | ||
| | | style="background: #667eea; color: white; padding: 12px; font-weight: bold; width: 30%;" | Setting | ||
| style="background: #667eea; color: white; padding: 12px; font-weight: bold; width: 25%;" | Default | |||
| style="background: #667eea; color: white; padding: 12px; font-weight: bold; width: 45%;" | When to Change | |||
|- | |- | ||
| | | style="padding: 12px; background: #f5f5f5; border: 1px solid #ddd;" | Window (sweep) | ||
| style="padding: 12px; background: #f5f5f5; border: 1px solid #ddd; font-family: monospace;" | Window2 | |||
| style="padding: 12px; background: #f5f5f5; border: 1px solid #ddd;" | Your sweep FFT has different name | |||
|- | |- | ||
| | | style="padding: 12px; border: 1px solid #ddd;" | Window (response) | ||
| style="padding: 12px; border: 1px solid #ddd; font-family: monospace;" | Window1 | |||
| style="padding: 12px; border: 1px solid #ddd;" | Your response FFT has different name | |||
|- | |- | ||
| | | style="padding: 12px; background: #f5f5f5; border: 1px solid #ddd;" | Number of harmonics | ||
| style="padding: 12px; background: #f5f5f5; border: 1px solid #ddd; font-family: monospace;" | 9 | |||
| style="padding: 12px; background: #f5f5f5; border: 1px solid #ddd;" | 5 (faster), 15 (more detailed) | |||
|} | |} | ||
'' | === How to Apply Changes === | ||
Β | |||
# Modify field value | |||
# Click '''Apply Configuration''' | |||
# Log displays "Configuration applied" β | |||
# Done! | |||
Β | |||
--- | |||
Β | |||
== π§ TROUBLESHOOTING == | |||
Β | |||
=== Issue 1: NVGate Shows "Disconnected" === | |||
Β | |||
<div style="background: #ffebee; border-left: 5px solid #d32f2f; padding: 20px; margin: 15px 0; border-radius: 5px;"> | |||
Β | |||
'''What it means:''' Application can't reach NVGate | |||
Β | |||
'''Solutions (in order):''' | |||
# Is NVGate actually open? Check your screen. | |||
# Restart NVGate | |||
# Restart the THD application | |||
# Check Windows firewall allows localhost connections | |||
# Call your IT department and cry | |||
Β | |||
'''Reality check:''' 99% of the time NVGate just wasn't open. No shame, happens to everyone. | |||
Β | |||
</div> | |||
Β | |||
=== Issue 2: Measurement Won't Start === | |||
Β | |||
<div style="background: #fff3e0; border-left: 5px solid #f57c00; padding: 20px; margin: 15px 0; border-radius: 5px;"> | |||
Β | |||
'''What it means:''' Something blocking the measurement | |||
Β | |||
'''Solutions:''' | |||
# Click '''Run Diagnostic''' - it will tell you exactly what's wrong | |||
# Common causes: | |||
#* No sweep configured in NVGate | |||
#* Markers not properly created | |||
#* Wrong window names in configuration | |||
Β | |||
The diagnostic is your friend. Use it! | |||
Β | |||
</div> | |||
Β | |||
=== Issue 3: THD Values Show "--.-" (dashes) === | |||
Β | |||
<div style="background: #e8f5e9; border-left: 5px solid #388e3c; padding: 20px; margin: 15px 0; border-radius: 5px;"> | |||
'''What it means:''' No data is being read from harmonics | |||
'''Check these:''' | |||
# Are FFT traces actually visible in NVGate? (Most common issue) | |||
# Is the sweep running? | |||
# Is there audio output to your speaker? | |||
# Are markers properly set up? | |||
Fix one of these and you're golden! | |||
</div> | |||
=== | === Issue 4: STOP Button Doesn't Work === | ||
= | <div style="background: #f3e5f5; border-left: 5px solid #7b1fa2; padding: 20px; margin: 15px 0; border-radius: 5px;"> | ||
'''What it means:''' Measurement is shutting down but taking its time | |||
'''Solution:''' Wait 5 seconds. Seriously. The app is cleaning up. | |||
If it still doesn't respond after 30 seconds: | |||
# Close the window | |||
# Restart the application | |||
# Continue with life | |||
</div> | |||
--- | --- | ||
== π‘ PRO TIPS == | |||
= | {| style="width: 100%; background: linear-gradient(135deg, #fff9c4, #fffde7); padding: 20px; border-radius: 10px; margin: 20px 0; border: 2px solid #fbc02d;" | ||
|- | |||
| '''Tip 1: Start Simple''' | |||
Always use default settings first. Change things later if needed. | |||
==== | '''Tip 2: Read the Log''' | ||
{| | The log console tells you everything. It's your best friend. | ||
Β | |||
'''Tip 3: Use Diagnostic''' | |||
When something's wrong, click "Run Diagnostic". It's like magic. | |||
Β | |||
'''Tip 4: Multiple Measurements''' | |||
One measurement is interesting. Five measurements is scientific. | |||
Β | |||
'''Tip 5: Document Results''' | |||
Take a screenshot or copy the final THD values. You'll forget otherwise. | |||
|} | |||
Β | |||
--- | |||
Β | |||
== β FREQUENTLY ASKED QUESTIONS == | |||
Β | |||
=== Q: Is THD 5% good? === | |||
Β | |||
'''A:''' For a speaker? Excellent! You can be proud of that equipment. π | |||
Β | |||
=== Q: Why does THD change with frequency? === | |||
Β | |||
'''A:''' Because speakers aren't perfect at all frequencies. Some frequencies cause more distortion than others. That's physics being weird. | |||
Β | |||
=== Q: Can I use this on any speaker? === | |||
Β | |||
'''A:''' Yes! Desktop speakers, studio monitors, subwoofers, car speakers - if it's connected to NVGate, we can measure it. | |||
Β | |||
=== Q: How many times should I measure? === | |||
Β | |||
'''A:''' Once for curiosity. Three times for reliability. Ten times if you're publishing a paper. | |||
Β | |||
=== Q: Can I export the results? === | |||
Β | |||
'''A:''' Yes! Copy text from the log console and paste into Excel, Word, or wherever you need it. | |||
Β | |||
=== Q: What if my project has different settings? === | |||
Β | |||
'''A:''' Use the Configuration panel to adjust. It's literally made for this. | |||
Β | |||
=== Q: Does this work over WiFi? === | |||
Β | |||
'''A:''' No. It only works locally (same computer or local network). WiFi would add too much latency. | |||
Β | |||
--- | |||
Β | |||
== π QUICK REFERENCE == | |||
Β | |||
{| style="width: 100%; border-collapse: collapse; margin: 20px 0;" | |||
|- | |- | ||
| | | style="background: linear-gradient(135deg, #667eea, #764ba2); color: white; padding: 15px; font-weight: bold; width: 25%; text-align: center;" | ACTION | ||
| style="background: linear-gradient(135deg, #667eea, #764ba2); color: white; padding: 15px; font-weight: bold; width: 25%; text-align: center;" | SHORTCUT | |||
| style="background: linear-gradient(135deg, #667eea, #764ba2); color: white; padding: 15px; font-weight: bold; width: 50%; text-align: center;" | RESULT | |||
|- | |- | ||
| | | style="padding: 15px; background: #f5f5f5; text-align: center;" | Launch App | ||
| style="padding: 15px; background: #f5f5f5; text-align: center; font-family: monospace;" | Double-click .bat file | |||
| style="padding: 15px; background: #f5f5f5; text-align: center;" | Window appears β | |||
|- | |- | ||
| | | style="padding: 15px; text-align: center;" | Start Measurement | ||
| style="padding: 15px; text-align: center; font-family: monospace;" | Click βΆ START | |||
| style="padding: 15px; text-align: center;" | Metrics begin updating β | |||
|- | |||
| style="padding: 15px; background: #f5f5f5; text-align: center;" | Stop Measurement | |||
| style="padding: 15px; background: #f5f5f5; text-align: center; font-family: monospace;" | Click β STOP | |||
| style="padding: 15px; background: #f5f5f5; text-align: center;" | Log shows "ended" β | |||
|- | |||
| style="padding: 15px; text-align: center;" | Run Diagnostic | |||
| style="padding: 15px; text-align: center; font-family: monospace;" | Click "Run Diagnostic" | |||
| style="padding: 15px; text-align: center;" | See all [OK] or [FAIL] β | |||
|- | |||
| style="padding: 15px; background: #f5f5f5; text-align: center;" | Change Config | |||
| style="padding: 15px; background: #f5f5f5; text-align: center; font-family: monospace;" | Click βΆ Configuration | |||
| style="padding: 15px; background: #f5f5f5; text-align: center;" | Apply changes β | |||
|} | |} | ||
==== | --- | ||
Β | |||
== π BEFORE YOU CONTACT SUPPORT == | |||
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Gather this information: | |||
* Screenshot of the error message | |||
* Last 5 lines of the log console | |||
* Your NVGate window names | |||
* Steps you took before the error | |||
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This helps us help you faster! π | |||
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{| style="width: 100%; background: linear-gradient(135deg, #667eea 0%, #764ba2 100%); color: white; padding: 30px; border-radius: 10px; margin: 30px 0; text-align: center;" | |||
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| style="font-size: 1.5em; font-weight: bold;" | You're Ready! | |||
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| style="font-size: 1.1em; margin-top: 10px; opacity: 0.95;" | Go measure some THD and make your speakers proud π΅ | |||
|} | |||
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'''Last Updated:''' 2026-04-15 | |||
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'''Version:''' 1.0 - User Guide | |||
'''Format:''' MediaWiki | |||
For technical details, see DOCUMENTATION_EN.txt | |||
Revision as of 14:54, 15 April 2026
THD SWEEP MEASUREMENT - USER GUIDE
Master the art of measuring Total Harmonic Distortion with style
| π΅ THD SWEEP MEASUREMENT |
| Professional Acoustic Testing Made Simple |
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β‘ QUICK START - 30 SECONDS
| STEP | ACTION |
| 1οΈβ£ Launch | Double-click Lancer_THD.bat
|
| 2οΈβ£ Connect | Check top right: β Connected |
| 3οΈβ£ Start | Click green βΆ START button
|
| 4οΈβ£ Monitor | Watch 4 metrics update live |
| 5οΈβ£ Stop | Click red β STOP button
|
β That's it! Your first THD measurement is complete. You're now a certified acoustic engineer. (Not really, but it feels good.)
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π YOUR INTERFACE - WHAT YOU SEE
π’ Status Indicators (Top Right)
| INDICATOR | MEANING |
| β NVGate Connected | Perfect! NVGate is ready to rock πΈ |
| β NVGate Disconnected | Oops! Start NVGate first π€ |
| β Measurement Running | Data is flowing! π |
| β Measurement Stopped | Ready for the next round βΈοΈ |
π Four Metric Cards
The heart of the interface. These four numbers tell the whole story:
| π THD (dB) |
π THD (%) |
π‘ Frequency |
β‘ Fundamental |
| Harmonic distortion (log scale) | Harmonic distortion (%) | Current sweep point | Signal strength |
| +5.42 dB | 58.294 % | 1234.56 Hz | 5.0e-01 V |
π¬ Log Console (Bottom)
Real-time messages with color coding:
| π’ GREEN | Everything OK - measurement working perfectly |
| π΄ RED | Error occurred - something needs attention |
| π΅ BLUE | Information - status updates and details |
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π― UNDERSTANDING YOUR RESULTS
THD (%) - The Easy Number
What is it? Percentage of unwanted harmonics in your signal.
Think of it this way:
- THD 5% = 95% pure signal, 5% noise
- THD 20% = 80% pure signal, 20% noise
The Quality Scale:
| π 1% - 5% | Excellent - Professional grade equipment |
| β 5% - 15% | Good - Solid speaker performance |
| β οΈ 15% - 30% | Acceptable - Consumer level equipment |
| β > 30% | Poor - Time for an upgrade π οΈ |
THD (dB) - The Technical Number
Same measurement as THD (%) but in decibels (logarithmic scale).
Quick Conversion Chart:
| THD % | THD dB | Quality |
| 1% | -40 dB | π Perfect |
| 3% | -30 dB | β Great |
| 10% | -20 dB | β Good |
| 30% | -10 dB | β οΈ Poor |
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π TYPICAL MEASUREMENT WORKFLOW
Pre-Measurement Checklist
Before you start, verify:
- β NVGate is open and ready
- β Sweep is configured (e.g., 10 Hz β 20 kHz)
- β FFT traces are visible on screen
- β Sine generator is active
- β Speaker is connected and working
Step-by-Step Workflow
| PHASE | WHAT TO DO | |
| 1οΈβ£ | Prepare | Open NVGate β Set sweep β Verify FFT visible |
| 2οΈβ£ | Launch App | Double-click Lancer_THD.bat β Check Connected status |
| 3οΈβ£ | Start | Click βΆ START β Watch log for "Starting THD Measurement" |
| 4οΈβ£ | Monitor | Watch metrics update β Frequency should increase β THD should be stable |
| 5οΈβ£ | Stop | Click β STOP β Watch for "Measurement ended" β Note final values |
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βοΈ CONFIGURATION
When Do I Need to Change This?
Honest answer: Almost never.
The default settings work for 95% of users. Only change if your NVGate project has:
- Different window names
- Different marker numbers
- Different DC input addresses
If you're not sure β Don't change anything. It works. Trust it.
How to Access Configuration
Click on βΆ Configuration (section expands)
Important Settings
| Setting | Default | When to Change |
| Window (sweep) | Window2 | Your sweep FFT has different name |
| Window (response) | Window1 | Your response FFT has different name |
| Number of harmonics | 9 | 5 (faster), 15 (more detailed) |
How to Apply Changes
- Modify field value
- Click Apply Configuration
- Log displays "Configuration applied" β
- Done!
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π§ TROUBLESHOOTING
Issue 1: NVGate Shows "Disconnected"
What it means: Application can't reach NVGate
Solutions (in order):
- Is NVGate actually open? Check your screen.
- Restart NVGate
- Restart the THD application
- Check Windows firewall allows localhost connections
- Call your IT department and cry
Reality check: 99% of the time NVGate just wasn't open. No shame, happens to everyone.
Issue 2: Measurement Won't Start
What it means: Something blocking the measurement
Solutions:
- Click Run Diagnostic - it will tell you exactly what's wrong
- Common causes:
- No sweep configured in NVGate
- Markers not properly created
- Wrong window names in configuration
The diagnostic is your friend. Use it!
Issue 3: THD Values Show "--.-" (dashes)
What it means: No data is being read from harmonics
Check these:
- Are FFT traces actually visible in NVGate? (Most common issue)
- Is the sweep running?
- Is there audio output to your speaker?
- Are markers properly set up?
Fix one of these and you're golden!
Issue 4: STOP Button Doesn't Work
What it means: Measurement is shutting down but taking its time
Solution: Wait 5 seconds. Seriously. The app is cleaning up.
If it still doesn't respond after 30 seconds:
- Close the window
- Restart the application
- Continue with life
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π‘ PRO TIPS
| Tip 1: Start Simple
Always use default settings first. Change things later if needed. Tip 2: Read the Log The log console tells you everything. It's your best friend. Tip 3: Use Diagnostic When something's wrong, click "Run Diagnostic". It's like magic. Tip 4: Multiple Measurements One measurement is interesting. Five measurements is scientific. Tip 5: Document Results Take a screenshot or copy the final THD values. You'll forget otherwise. |
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β FREQUENTLY ASKED QUESTIONS
Q: Is THD 5% good?
A: For a speaker? Excellent! You can be proud of that equipment. π
Q: Why does THD change with frequency?
A: Because speakers aren't perfect at all frequencies. Some frequencies cause more distortion than others. That's physics being weird.
Q: Can I use this on any speaker?
A: Yes! Desktop speakers, studio monitors, subwoofers, car speakers - if it's connected to NVGate, we can measure it.
Q: How many times should I measure?
A: Once for curiosity. Three times for reliability. Ten times if you're publishing a paper.
Q: Can I export the results?
A: Yes! Copy text from the log console and paste into Excel, Word, or wherever you need it.
Q: What if my project has different settings?
A: Use the Configuration panel to adjust. It's literally made for this.
Q: Does this work over WiFi?
A: No. It only works locally (same computer or local network). WiFi would add too much latency.
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π QUICK REFERENCE
| ACTION | SHORTCUT | RESULT |
| Launch App | Double-click .bat file | Window appears β |
| Start Measurement | Click βΆ START | Metrics begin updating β |
| Stop Measurement | Click β STOP | Log shows "ended" β |
| Run Diagnostic | Click "Run Diagnostic" | See all [OK] or [FAIL] β |
| Change Config | Click βΆ Configuration | Apply changes β |
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π BEFORE YOU CONTACT SUPPORT
Gather this information:
- Screenshot of the error message
- Last 5 lines of the log console
- Your NVGate window names
- Steps you took before the error
This helps us help you faster! π
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| You're Ready! |
| Go measure some THD and make your speakers proud π΅ |
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Last Updated: 2026-04-15
Version: 1.0 - User Guide
Format: MediaWiki
For technical details, see DOCUMENTATION_EN.txt