
MetalRTMarch 15, 2026
MetalRT Now Does Speech-to-Speech. 1.52x Faster Than mlx-audio.
MetalRT adds native speech-to-speech support. 1.68s end-to-end latency, 123 tok/s generation throughput, 1.52x faster than mlx-audio on a single M4 Max.
Engineering notes

MetalRT adds native speech-to-speech support. 1.68s end-to-end latency, 123 tok/s generation throughput, 1.52x faster than mlx-audio on a single M4 Max.

MetalRT adds VLM support and wins every decode benchmark. 279 tok/s vision decode, 92ms time-to-output, 1.22x faster than mlx-vlm across all resolutions on a single M4 Max.

MetalRT becomes the first inference engine to handle LLMs, Speech-to-Text, and Text-to-Speech on Apple Silicon. 101ms to transcribe 70 seconds of audio. 178ms to synthesize speech. 4.6x faster than Apple MLX.

MetalRT delivers 658 tok/s decode and 6.6ms time-to-first-token, winning decode on 3 of 4 models we tested on a single M4 Max.