Tuning RTA Measurement
RTA (Real-Time Analyzer) shows you exactly what the system sounds like by measuring the frequency response with a calibrated microphone. It's the foundation of accurate tuning — and it's required for Auto-Tune.
On this page
What RTA Shows You
The RTA display is a live graph of frequency vs. level:
- X-axis (left to right): frequency from 20 Hz (deep bass) to 20,000 Hz (highest treble)
- Y-axis (up and down): loudness level in decibels (dB)
A flat line from left to right would mean the system is perfectly balanced — every frequency is the same loudness. In reality, you'll see peaks (too loud at that frequency) and dips (too quiet). EQ is used to fix them.
Microphone Requirements
You need a calibrated measurement microphone. This is different from a regular recording mic — it's designed to measure accurately rather than sound good on vocals.
Recommended Mics (by tier)
| Level | Mic |
|---|---|
| Entry | Dayton Audio iMM-6 |
| Mid | miniDSP UMIK-1 |
| Pro | Earthworks M30 |
| Comp | Earthworks M50 |
What matters in a measurement mic
- Flat frequency response (deviation ≤ ±3 dB from 20–20k Hz)
- Comes with (or has downloadable) calibration file (.cal or .txt)
- USB or 3.5mm connection to your laptop
- Omnidirectional pickup pattern
Uploading Your Calibration File
Every measurement mic has small frequency-response variations. A calibration file (.cal, .frd, or .txt) corrects for these variations, giving you accurate readings.
Microphone Placement
Where you put the mic matters. For car audio, the standard is:
Driver's Position (most common)
- Mic at ear height in the driver's seat headrest
- Pointing straight up (omnidirectional mics)
- Windows closed, car off (or engine running at idle if measuring with vehicle on)
Multi-Position (advanced)
- Average of multiple positions: driver + passenger + rear seats
- Used for competition judging or commercial installs serving multiple passengers
- RTA coaching mode in AI Advisor guides this process
Running a Measurement
Reading the RTA Display
The RTA displays two key elements:
Live RTA (animated)
The moving bars or line showing the real-time frequency response as it changes. This is what the mic is hearing right now.
Bar colors by zone:
- ■ Sub (20–80 Hz)
- ■ Mid Bass (80–300 Hz)
- ■ Midrange (300–3kHz)
- ■ Highs (3kHz–20kHz)
Actual Measurement Line (sticky)
After you click Capture, a solid line appears — this is the "actual" measurement. It stays on screen while you make EQ changes, so you can compare before and after.
The sticky line updates automatically after Auto-Tune writes a correction pass to the DSP.
Target Curves
A target curve shows what you're aiming for — the ideal frequency response shape. Tuning Labs includes several named curves:
| Curve | Character | Best For |
|---|---|---|
| Flat | 0 dB across all frequencies | Reference / starting point |
| Harman Curve | Gentle bass boost, slight treble roll-off | Most listeners; audiophile preference |
| Audiofrog/Wehmeyer | Competition-tuned, neutral | Competition installs |
| X-Curve (IEC) | High-frequency roll-off above 2 kHz | Home theaters / cinema |
| Custom | Draw your own | Customer-specific preferences |