---
license: cc-by-nc-4.0
tags:
  - lora
  - peft
  - speech-language-models
  - frozen-adapter
base_model: Qwen/Qwen3-8B
---

# BTA — Stage 6 LoRA r=4

Minimal-LoRA upper-bound experiment: rank 4, α=16 (α/r=4) on
Qwen3-8B `q_proj`/`v_proj` across all 36 transformer blocks (72 LoRA
modules total, ~1.92M LoRA parameters). The R1.8 adapter and
$C_\phi$ heads are FROZEN; only the LoRA matrices update.

**Pre-registered oracle-stability gate:** Probe-G-oracle re-confirm
within ±2pp of the Stage 1a anchor 0.7871. Result: 0.7970 (+0.99pp drift) → PASS.

**Outcome branch:** weak-negative. Probe-G$_{\mathrm{neutral}}$ = 0.4926
(R0 - 0.0196), 0.4pp below the H2 NULL band on the negative side.
Minimal LoRA at this rank preserves the oracle but does not recover
audio-conditional consumer use of the R1.8 representation.

**Files:** PEFT LoRA weights (`adapter_config.json`, `adapter_model.safetensors`).
Load via `PeftModel.from_pretrained` on top of base `Qwen/Qwen3-8B`.

**Files / metrics:**

| | Value |
|---|---|
| Oracle re-confirm | 0.7970 |
| Probe-G$_{\mathrm{neutral}}$ | 0.4926 |
| Probe-G$_{\mathrm{total}}$ | 0.6277 |
| Probe-G$_{\mathrm{explicit}}$ | 0.7629 |
| Probe-K linear (R1.8 frozen) | 0.2265 |
| Probe-K MLP-2 (R1.8 frozen) | 0.3120 |

**Code / paper:** <https://github.com/Nurgali-Kadyrbek/frozen-speech-llm-stress>

License: CC-BY-NC-4.0.