Samsung Q990C – Firmware 1010.5: My Complete Calibration Journey (Step-by-Step)

[GTR-87]

💡 TL;DR

• 1010.5 tightened DSP timing and sub integration.

• You need to level-match first, then run SpaceFit Pro with Bass Enhancement ON.

• Surround Mode only for calibration and listening. Adaptive dynamically shifts trims—avoid it.

• Proper sub placement and multi-level calibration fix the 250–500 Hz dip.

• The result: balanced, powerful, reference-style sound.

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🧩 Final Settings

• Sound Mode: Surround

• Bass: 5

• Treble: 1

• Subwoofer: 1

• Bass Enhancement: ON (always)

• SpaceFit Pro: Used for calibration → then OFF for daily listening (the DSP keeps its filters)

Channel trims (after SPL matching):

Channel Level

Center	0
Side	–1
Wide	0
Front Top	0
Rear	–5
Rear Top	–2
Rear Side	0

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🎚️ Step 1 – Level Matching (Before SpaceFit Pro)

Use a reliable pink-noise source (I used the TechnoDad Digital Kit) and a smartphone SPL app or meter at the main seat.
Adjust each channel until all measure roughly the same dB (usually 75 dB at reference).
This ensures SpaceFit sees a balanced system when it analyzes reflections and low-frequency summing.

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📍 Step 2 – Subwoofer Placement

This changed everything.

• Corner = boomy (40 Hz peak)

• Mid-wall = flat but weak

• Best: slightly off-center along the front wall, ~20–25 cm from wall, angled slightly toward the MLP.

This position eliminated a 70 Hz resonance and improved phase with the bar’s woofers.

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⚙️ Step 3 – SpaceFit Pro Calibration Routine

Goal: teach the DSP how your room behaves across different loudness levels.

1. Keep Sound Mode = Surround.

2. Keep Bass Enhancement ON (always).

3. Turn SpaceFit Pro ON.

4. Play Periodic Pink Noise (LFE channel) through your source (I used Plex on NVIDIA Shield).

5. Run SpaceFit for 30 seconds each at these master volumes:
   23 → 18 → 15 → 11 → 8 → 5 → 3
   (Wait ~30 seconds between each so the DSP settles.)

6. After finishing all passes, turn SpaceFit Pro OFF for playback.
   The calibration filters stay applied internally until re-run.

✅ This multi-level approach completely smoothed the 250–500 Hz region and tightened the sub-to-bar transition.

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🔍 Step 4 – Verify with HouseCurve (optional)

Using the iPhone’s compensated mic, my final curve tracked almost perfectly from 35 Hz → 15 kHz with a gentle –1 dB/octave tilt—no mid-bass bloat, no holes.
Bass now extends cleanly to 30 Hz while vocals stay crystal clear.

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🎵 Listening Impressions

I genuinely can’t stop listening.
The Q990C now has the dynamics of a full AVR setup: bass that hits hard but never booms, midrange that’s lifelike, and surround imaging so precise that sounds appear from places where there aren’t even speakers.

Atmos demos like Leaf and Amaze sound effortless—objects move naturally through space instead of jumping channels. Stereo music gained width and depth I’ve never heard from a soundbar before.

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📋 Checklist Summary

• Place sub (slightly off-center, ~25 cm from wall)

• Match levels first using pink noise

• Surround mode ON

• Bass Enhancement ON (always)

• Run SpaceFit Pro (30 s each at 23 → 18 → 15 → 11 → 8 → 5 → 3)

• Turn SpaceFit OFF after calibration

• Verify/Enjoy

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❤️ Final Thoughts

Firmware 1010.5 didn’t ruin the Q990C—it unlocked its potential.
Once you calibrate it right, it’s on another level: clean, balanced, cinematic.
I’ve owned several AVR setups and this genuinely holds its own.

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