TTS Bench — Speed — mac-cloning

Rig: mac-m4 — Apple M4 (10C) · Apple M4 GPU (MPS) · 16 GB RAM · Darwin 25.5.0

Label: cloning · jo — ref jo.wav

TTFA = time to first audio (ms; lower is better). RTF = real-time factor (× realtime; higher is better; e.g. 10× means 10 sec of audio generated per 1 sec of compute). Cold = first run after process start; warm = subsequent runs.

Speed winners

Fastest (this cloning run): Pocket-TTS (cpu) — 8.01× warm RTF, 44ms warm TTFA

Model	Device	TTFA cold	TTFA warm	RTF cold	RTF warm	Peak RAM	Peak VRAM	Size
Pocket-TTS	cpu	46ms	44ms	7.91×	8.01×	2.46 GB	—	100M
OpenVoice v2	mps	2.88s	1.01s	2.26×	5.91×	—	—	~100M
NeuTTS Nano	cpu	785ms	281ms	2.19×	3.01×	5.83 GB	—	229M
NeuTTS Nano	mps	1.54s	493ms	1.78×	2.87×	1.38 GB	—	229M
OpenVoice v2	cpu	6.54s	2.40s	1.24×	2.49×	—	—	~100M
NeuTTS Air	cpu	1.50s	359ms	1.57×	2.14×	4.96 GB	—	748M
NeuTTS Air	mps	2.35s	562ms	1.26×	2.10×	1.56 GB	—	748M
MOSS-TTS-Nano	cpu	5.74s	3.66s	1.28×	1.93×	—	—	100M
Coqui XTTS-v2	mps	12.06s	6.80s	1.04×	1.59×	1.87 GB	—	750M
Coqui XTTS-v2	cpu	5.67s	6.73s	1.35×	1.36×	4.37 GB	—	750M
Chatterbox Turbo	mps	8.12s	14.00s	0.80×	1.10×	2.57 GB	—	744M
Chatterbox Turbo	cpu	6.62s	6.39s	0.98×	1.03×	4.92 GB	—	744M
MOSS-TTS-Nano	mps	25.59s	18.57s	0.29×	0.40×	—	—	100M
Fish Speech 1.5	cpu	18.30s	18.36s	0.33×	0.34×	—	—	~500M
Chatterbox	mps	36.45s	34.12s	0.25×	0.33×	1000 MB	—	1.2B
Chatterbox	cpu	24.68s	22.69s	0.30×	0.32×	5.55 GB	—	1.2B
Fish Speech 1.5	mps	21.55s	21.91s	0.29×	0.31×	—	—	~500M
Qwen3-TTS 1.7B Base	cpu	26.94s	22.01s	0.22×	0.26×	3.66 GB	—	1.7B
Sesame CSM-1B	cpu	32.32s	23.57s	0.18×	0.24×	6.44 GB	—	1B
Zonos v0.1	cpu	52.99s	51.88s	0.15×	0.15×	—	—	1.6B
IndexTTS-2	cpu	79.63s	44.94s	0.08×	0.15×	266 MB	—	1.5B
ZipVoice 123M (4/5 ok)	cpu	33.60s	37.61s	0.13×	0.10×	2.13 GB	—	123M
F5-TTS v1	mps	44.88s	45.26s	0.10×	0.09×	1.29 GB	—	330M
F5-TTS v1	cpu	47.24s	47.06s	0.09×	0.09×	2.32 GB	—	330M
OuteTTS 1.0 1B (2/5 ok)	cpu	72.93s	71.42s	0.04×	0.04×	6.83 GB	—	1B
OuteTTS 1.0 1B (2/5 ok)	mps	76.37s	72.18s	0.04×	0.04×	974 MB	—	1B
LuxTTS	cpu	LuxTTS install failed (piper-phonemize has no Windows wheels)
LuxTTS	mps	LuxTTS install failed (piper-phonemize has no Windows wheels)
VoxCPM2 2B	cpu	Timed out after 10 min — model too slow at this prompt length
Mars5-TTS	cpu	Timed out after 10 min — model too slow at this prompt length
ZipVoice 123M	mps	Skipped — out of memory (model exceeds available RAM)
OmniVoice	cpu	39.56s	—	0.18×	—	4.53 GB	—	~1B
OmniVoice (4/5 ok)	mps	26.08s	—	0.21×	—	1008 MB	—	~1B

Model

Device

TTFA cold

TTFA warm

RTF cold

RTF warm

Peak RAM

Peak VRAM

Size

Pocket-TTS

cpu

46ms

44ms

7.91×

8.01×

2.46 GB

—

100M

OpenVoice v2

mps

2.88s

1.01s

2.26×

5.91×

—

~100M

NeuTTS Nano

cpu

785ms

281ms

2.19×

3.01×

5.83 GB

—

229M

NeuTTS Nano

mps

1.54s

493ms

1.78×

2.87×

1.38 GB

—

229M

OpenVoice v2

cpu

6.54s

2.40s

1.24×

2.49×

—

~100M

NeuTTS Air

cpu

1.50s

359ms

1.57×

2.14×

4.96 GB

—

748M

NeuTTS Air

mps

2.35s

562ms

1.26×

2.10×

1.56 GB

—

748M

MOSS-TTS-Nano

cpu

5.74s

3.66s

1.28×

1.93×

—

100M

Coqui XTTS-v2

mps

12.06s

6.80s

1.04×

1.59×

1.87 GB

—

750M

Coqui XTTS-v2

cpu

5.67s

6.73s

1.35×

1.36×

4.37 GB

—

750M

Chatterbox Turbo

mps

8.12s

14.00s

0.80×

1.10×

2.57 GB

—

744M

Chatterbox Turbo

cpu

6.62s

6.39s

0.98×

1.03×

4.92 GB

—

744M

MOSS-TTS-Nano

mps

25.59s

18.57s

0.29×

0.40×

—

100M

Fish Speech 1.5

cpu

18.30s

18.36s

0.33×

0.34×

—

~500M

Chatterbox

mps

36.45s

34.12s

0.25×

0.33×

1000 MB

—

1.2B

Chatterbox

cpu

24.68s

22.69s

0.30×

0.32×

5.55 GB

—

1.2B

Fish Speech 1.5

mps

21.55s

21.91s

0.29×

0.31×

—

~500M

Qwen3-TTS 1.7B Base

cpu

26.94s

22.01s

0.22×

0.26×

3.66 GB

—

1.7B

Sesame CSM-1B

cpu

32.32s

23.57s

0.18×

0.24×

6.44 GB

—

Zonos v0.1

cpu

52.99s

51.88s

0.15×

—

1.6B

IndexTTS-2

cpu

79.63s

44.94s

0.08×

0.15×

266 MB

—

1.5B

ZipVoice 123M (4/5 ok)

cpu

33.60s

37.61s

0.13×

0.10×

2.13 GB

—

123M

F5-TTS v1

mps

44.88s

45.26s

0.10×

0.09×

1.29 GB

—

330M

F5-TTS v1

cpu

47.24s

47.06s

0.09×

2.32 GB

—

330M

OuteTTS 1.0 1B (2/5 ok)

cpu

72.93s

71.42s

0.04×

6.83 GB

—

OuteTTS 1.0 1B (2/5 ok)

mps

76.37s

72.18s

0.04×

974 MB

—

LuxTTS

cpu

LuxTTS install failed (piper-phonemize has no Windows wheels)

LuxTTS

mps

LuxTTS install failed (piper-phonemize has no Windows wheels)

VoxCPM2 2B

cpu

Timed out after 10 min — model too slow at this prompt length

Mars5-TTS

cpu

Timed out after 10 min — model too slow at this prompt length

ZipVoice 123M

mps

Skipped — out of memory (model exceeds available RAM)

OmniVoice

cpu

39.56s

—

0.18×

—

4.53 GB

—

~1B

OmniVoice (4/5 ok)

mps

26.08s

—

0.21×

—

1008 MB

—

~1B