Many voicebots these days need the speed of a fast LLM but the reasoning capabilities of a heavier LLM. To achieve this, modern products are shifting to a dual-model framework. An example is the recent GPT-Live release where a realtime speech-to-speech model has access to GPT5.5 in the background.
This is not a new design, but most of us simply use a heavier model in the background as a tool instead of trying out advanced techniques. For this issue of Computational Conversations I design a few of these techniques to use a fast foreground and slow background model.
I also reproduce a common speech-to-speech pattern of injecting knowledge from a larger LLM live midway (example from Sakana AI) in bot utterance without training a new model, which might be interesting if you like exhausting engineering options before going to model training.
Read more in the full post here.