Every producer knows the feeling: you've been mixing for hours, tweaking EQ, adjusting compression, checking on different speakers... and you still don't know if it's done. This guide gives you 12 concrete, measurable checkpoints so you never have to guess again.
The biggest mistake in mixing isn't bad EQ or too much compression — it's not knowing when to stop. Over-mixing kills more tracks than under-mixing ever did.
The #1 issue we see in mixes analyzed on MixDiagnose is frequency imbalance. A single range — usually 200-400 Hz or 2-5 kHz — dominates everything else, making the mix sound muddy or harsh.
How to check: Load a spectrum analyzer. Look at the overall frequency curve. No single octave should be more than 6-8 dB louder than its neighbors. The curve should slope gently downward from low to high frequencies.
Loudness is the most measurable aspect of a mix, yet most producers guess. LUFS (Loudness Units Full Scale) is the standard, and every streaming platform has a target:
| Platform | Target LUFS | What happens if you exceed it |
|---|---|---|
| Spotify | -14 LUFS | Turned down + limiter applied |
| Apple Music | -16 LUFS | Turned down |
| YouTube | -14 LUFS | Turned down |
| SoundCloud | -14 LUFS | Turned down (on uploads) |
| CD / Master | -9 to -7 LUFS | No normalization — go loud |
For a pre-master mix: aim for -18 to -14 LUFS integrated. If your mix is already at -8 LUFS, you've essentially mastered it — and left no headroom for the mastering engineer.
True peak (dBTP) measures the actual peak level of the waveform, including inter-sample peaks. Going above -1 dBTP on a mix means you're already clipping on some playback systems.
Target: -1 to -3 dBTP on the mix. Leave room for the mastering engineer to push the limiter.
Crest factor is the difference between peak and average level. It's the single best number for "how alive does this mix feel?"
| Crest Factor | Assessment | What it means |
|---|---|---|
| ≥12 dB | Excellent | Wide dynamic range, very punchy |
| 9-12 dB | Good | Healthy dynamics |
| 6-9 dB | Moderate | Starting to sound compressed |
| 4-6 dB | Poor | Squashed — over-compressed |
| <4 dB | Dead | Brickwalled — no dynamics left |
How to fix: If your crest factor is below 6 dB, you have too much compression on the mix bus. Remove or reduce bus compression. Let individual tracks carry the compression, not the stereo bus.
Your mix should sound good in mono. Many playback systems — phone speakers, Bluetooth speakers, club systems — sum to mono. If your mix falls apart in mono, you have phase issues.
Check every track in your mix for clipping. Not the master bus — individual tracks. A single clipped snare or vocal take can introduce harshness that no amount of EQ will fix.
How to check: Solo each track and watch the meter. Any track hitting 0 dBFS (digital full scale) is clipping. Add gain staging: pull every track down so peaks sit around -6 to -12 dBFS.
The low end (20-120 Hz) is the most common problem area. Too much energy here makes the mix sound muddy on speakers and overwhelming on headphones.
Fix: High-pass filter everything that doesn't need low end — vocals at 80-100 Hz, guitars at 80 Hz, most synths at 40-60 Hz. Only kick, bass, and sub-bass should occupy 20-120 Hz.
The vocal should be clearly audible and intelligible at all times. If you have to strain to hear the words, the vocal is buried.
Test: Close your eyes. Can you understand every word? If not, either the vocal level is too low, or frequencies in the 1-3 kHz range are being masked by other instruments.
This is the classic test, and it's still the best. Your mix should sound good on:
If your mix sounds great on monitors but thin on phone speakers, you have a low-end problem. If it sounds great on headphones but muddy on monitors, you have a midrange buildup.
Harshness lives in the 2-5 kHz range. Sibilance lives in the 5-8 kHz range. Both will make listeners turn down the volume — and they won't come back.
Fix: De-ess vocals. Cut 1-2 dB at 3 kHz on instruments that sound harsh. If the whole mix sounds harsh, a gentle cut at 4 kHz on the mix bus can help.
Every element should have a deliberate position in the stereo field and depth field. If everything is up front and wide, nothing has space. Use reverb and delay to create depth — closer elements have less reverb, distant elements have more.
The final checkpoint isn't technical — it's psychological. Step away from the mix for 24 hours. Come back with fresh ears. If it still sounds good, it's done. If you hear problems you didn't hear yesterday, fix those first.
Your ears adapt to a mix within 30 minutes. After that, you're not hearing the mix — you're hearing your memory of it. The 24-hour rule resets your ears.
Upload your track to MixDiagnose and get an instant Mix Score (0-100), with specific frequency, loudness, and dynamics issues flagged by severity.
Analyze your mix free →| Checkpoint | Target | Red Flag |
|---|---|---|
| LUFS Integrated | -18 to -14 | Louder than -10 |
| True Peak | -1 to -3 dBTP | Above -1 dBTP |
| Crest Factor | ≥6 dB | Below 4 dB |
| Frequency Balance | No range +6 dB | Mud at 200-400 Hz |
| Stereo (mono) | Acceptable | Phase cancellation |
| Track clipping | Peaks ≤ -6 dBFS | Any track at 0 dBFS |
If all 12 check out — your mix is ready for mastering. Not before.
MixDiagnose analyzes your track in seconds and tells you exactly what to fix before you pay for mastering.
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