# Background Noise — VoiceNet dimension guide

*Category:* Language & Recording · *code:* `vn_BKGN` · *slot:* 73

This dimension measures the prominence and intrusiveness of ambient sound. Merge the `__high` / `__low` LoRA from `laion/moss-voicenet-dimension-loras` at 25/50/75/100/125%. Costs are shifts vs. the 24-sample neutral baseline.

**TL;DR.** **Background Noise** controls the prominence and intrusiveness of ambient sound. The **__high** LoRA shifts it +0.08 at 100% (worst cost: genuineness -0.04); the **__low** LoRA shifts it -0.09 at 50% (worst cost: speech quality -0.15). The **__low** direction is the stronger, more reliable knob here.

## ▲ HIGH — Background Noise __high

| dose | target | Δtarget | Δgenu | Δblend | Δqual |
|---|---|---|---|---|---|
| baseline (0%) | 0.399 | — | — | — | — |
| 25% | 0.380 | -0.02 | -0.01 | -0.01 | +0.01 |
| 50% | 0.381 | -0.02 | -0.02 | +0.07 | -0.09 |
| 75% | 0.446 | +0.05 | -0.02 | -0.01 | +0.02 |
| 100% ★ | 0.478 | +0.08 | -0.04 | +0.02 | +0.09 |
| 125% | 0.432 | +0.03 | +0.00 | +0.03 | -0.08 |

- **EmoNet emotion** — ↑ Hope/Enthusiasm/Optimism (+0.47), Contentment (+0.40), Interest (+0.35); ↓ Fatigue/Exhaustion (-0.65), Distress (-0.45), Helplessness (-0.42)
- **VoiceNet dimension** — ↑ Mixed Resonance (+0.68), Register (+0.67), Mask Resonance (+0.64); ↓ Disfluency (-0.63), Perceived Gender (-0.57), Cognitive Load (-0.52)

Merging **Background Noise __high** drives the dimension: at the recommended **100%** dose the measured Background Noise score moves from a 0.40 baseline to 0.48 (a +0.08 shift). The dose-response is clean and monotonic — each step pushes the dimension further. That reach is nearly free — the biggest hit is to **genuineness** (-0.04); across the board genuineness -0.04, burst-blend +0.02, speech quality +0.09. Emotionally it reads as Hope/Enthusiasm/Optimism (r 0.47), Contentment (0.40) and Interest (0.35), and it moves away from Fatigue/Exhaustion, Distress and Helplessness. On other voice dimensions it co-moves most with Mixed Resonance (0.68), Register (0.67) and Mask Resonance (0.64), while pulling down Disfluency, Perceived Gender and Cognitive Load. Practical call: merge __high at **75–100%**; expect Hope/Enthusiasm/Optimism and Mixed Resonance to rise and genuineness to fall. If you don’t want Hope/Enthusiasm/Optimism bleeding in, offset it with a prompt cue toward Fatigue/Exhaustion to keep the background noise shift without the side-effect.

## ▼ LOW — Background Noise __low

| dose | target | Δtarget | Δgenu | Δblend | Δqual |
|---|---|---|---|---|---|
| baseline (0%) | 0.399 | — | — | — | — |
| 25% | 0.440 | +0.04 | -0.02 | -0.06 | +0.04 |
| 50% ★ | 0.305 | -0.09 | +0.01 | -0.10 | -0.15 |
| 75% | 0.389 | -0.01 | +0.01 | -0.15 | -0.11 |
| 100% | 0.374 | -0.02 | -0.02 | -0.28 | -0.10 |
| 125% | 0.313 | -0.09 | +0.01 | -0.38 | -0.20 |

- **EmoNet emotion** — ↑ Contentment (+0.49), Hope/Enthusiasm/Optimism (+0.44), Interest (+0.44); ↓ Fatigue/Exhaustion (-0.52), Distress (-0.42), Pain (-0.42)
- **VoiceNet dimension** — ↑ Recording Quality (+0.71), Register (+0.64), Narrator Style (+0.60); ↓ Disfluency (-0.64), Perceived Gender (-0.50), Genuineness (-0.42)

Merging **Background Noise __low** lowers the dimension: at the recommended **50%** dose the measured Background Noise score moves from a 0.40 baseline to 0.30 (a -0.09 shift). The dose-response is monotonic but it saturates early, so higher doses add little. That reach is a real cost — the biggest hit is to **speech quality** (-0.15); across the board genuineness +0.01, burst-blend -0.10, speech quality -0.15. Emotionally it reads as Contentment (r 0.49), Hope/Enthusiasm/Optimism (0.44) and Interest (0.44), and it moves away from Fatigue/Exhaustion, Distress and Pain. On other voice dimensions it co-moves most with Recording Quality (0.71), Register (0.64) and Narrator Style (0.60), while pulling down Disfluency, Perceived Gender and Genuineness. Practical call: merge __low at **25–75%**; expect Contentment and Recording Quality to rise and speech quality to fall. If you don’t want Contentment bleeding in, offset it with a prompt cue toward Fatigue/Exhaustion to keep the background noise shift without the side-effect.

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