Version History

This page summarizes all VoxCPM releases, including feature comparison, version highlights, and migration guidance.

Quick Comparison

Feature

VoxCPM 1.0

VoxCPM 1.5

VoxCPM 2

Parameters

640M

800M

2B

Audio Output

16kHz

44.1kHz

48kHz

Languages

2 (zh, en)

2 (zh, en)

30

Patch Size

2

4

4

LM Token Rate

12.5Hz

6.25Hz

6.25Hz

Max Sequence Length

4096

4096

8192

Residual LM Fusion

Additive

Additive

Concat + Projection

DiT Conditioning

Single token (add)

Single token (add)

Multi-token (concat)

Reference Audio

Prompt continuation

Prompt continuation

Isolated ref channel

Voice Design

—

—

✅

Style Control

—

—

✅

SFT / LoRA

✅

✅

✅

RTF (RTX 4090)

~0.17

~0.15

~0.3

For a detailed explanation of the architecture components (four-stage pipeline, AudioVAE, Local DiT), see Architecture.

VoxCPM 2

VoxCPM 2 is the latest major release — a 2B parameter model trained on 2.36 million hours of multilingual data. It represents a significant leap in capacity, quality, and controllability over the 1.x series.

Key characteristics:

  • 48kHz audio output via AudioVAE V2 (asymmetric 16kHz encode → 48kHz decode)

  • 30-language multilingual support

  • Voice Design: create a voice from natural-language description, no reference audio needed

  • Style Control: control emotion, pace, and speaking style of a cloned voice via text tags

  • Isolated reference channel for voice cloning (no matching transcript required)

  • Concat-Projection residual LM fusion and multi-token DiT conditioning for richer expressiveness

  • Built on a MiniCPM-4 backbone

Use VoxCPM 2 for all new projects. It is the recommended default for multilingual synthesis, voice cloning, voice design, and production deployment.

VoxCPM 1.5

VoxCPM 1.5 is the final 1.x upgrade before VoxCPM 2. It improves audio quality and efficiency while keeping the core context-aware generation and zero-shot voice cloning workflow familiar to existing 1.x users.

Key characteristics:

  • 44.1kHz output

  • 6.25Hz LM token rate

  • patch size increased from 2 to 4

  • simpler migration path for existing VoxCPM 1.0 users

Use VoxCPM 1.5 when you want a lighter Chinese/English checkpoint than VoxCPM 2, while keeping stronger output quality than VoxCPM 1.0.

VoxCPM 1.0

VoxCPM 1.0 is the original tokenizer-free VoxCPM release. It remains useful as the baseline reference point for the family and for older experiments built around the original 0.5B checkpoint.

Key characteristics:

  • 600M parameter size

  • 16kHz output

  • original VoxCPM architecture release

  • benchmark reference for early VoxCPM results

Use VoxCPM 1.0 when you need the smallest historical checkpoint or want to compare against the original baseline behavior.

Migration Guidance

  • New projects should start with VoxCPM 2.

  • Existing VoxCPM 1.0 users should generally move to VoxCPM 1.5 first if they need a lower-risk 1.x upgrade path.

  • If you need multilingual synthesis, Voice Design, Style Control, or 48kHz output, move directly to VoxCPM 2.

Detailed Pages