Music 2.6: BPM/Key Control, 6-Minute Songs, and 14+ Section Tags
We upgraded from Music-1.5 to Music-2.6. Here's what changed, why it matters, and real scenarios where the new features make a difference.
What Changed
BPM and Key Control
Say "E minor, 90 BPM" in your prompt and Music-2.6 hits it with 99%+ accuracy. No more guessing whether the tempo is right for your video or podcast intro.
Songs Up to 6 Minutes
Music-1.5 maxed out at ~2 minutes. Music-2.6 generates tracks up to 6 minutes (typically 2-4), long enough for a full song with multiple verses, bridge, and outro.
14+ Section Tags
Control song structure with [Intro], [Verse], [Pre Chorus], [Chorus], [Bridge], [Drop], [Solo], [Hook], [Outro], and more. Music-1.5 supported 5 basic tags.
Better Vocals and Instruments
Natural-sounding vocals with realistic timbre, breathing, and pitch transitions. Expanded instrument library including orchestral and traditional instruments. Style-aware mixing that adapts to genre.
Instrumental Mode
New is_instrumental flag generates full arrangements without vocals. Background music for videos, podcasts, or games without needing to strip vocals later.
Auto-Generated Lyrics
New lyrics_optimizer flag. Describe the vibe in your prompt, skip the lyrics field, and the AI writes them for you.
Side-by-Side Comparison
| Feature | Music-1.5 (old) | Music-2.6 (new) |
|---|---|---|
| Price | 100 sats | 300 sats |
| Song length | ~2 min | Up to 6 min |
| Prompt limit | 300 chars | 2,000 chars |
| Lyrics limit | 600 chars | 3,500 chars |
| BPM/key control | No | Yes (99%+) |
| Section tags | 5 basic | 14+ |
| Instrumental mode | No | Yes |
| Auto lyrics | No | Yes |
| Vocal quality | Good | Realistic timbre + breathing |
| Seed control | No | Yes |
Real Use Cases That Weren't Possible Before
YouTube creator needs a 4-minute outro track in D major at 72 BPM
With Music-1.5, you'd describe "slow, calm outro music" and hope the key and tempo landed close enough. Half the time the AI picked a different key and the track clashed with your video's audio.
With Music-2.6: Put "D major, 72 BPM, gentle piano outro, ambient pads, no drums" in the prompt. Set is_instrumental: true. Get a 4-minute track that actually matches your video's key. One try, 300 sats.
Podcast producer needs a structured jingle with intro, hook, and outro
Music-1.5 generated a single continuous piece. You couldn't tell it "8 bars of intro, then the hook, then fade out." You'd get a blob and chop it in Audacity.
With Music-2.6: Use section tags: [Intro] for the 8-bar buildup, [Hook] for the catchy part, [Outro] for the fade. The AI follows your arrangement, not its own.
Indie game dev needs background music that loops at a specific tempo
Game music needs precise BPM for looping. Music-1.5 didn't expose tempo control, so you'd generate and time-stretch in post — degrading quality.
With Music-2.6: "A minor, 120 BPM, chiptune meets orchestral, adventure game overworld theme." Instrumental mode. The output is at exactly 120 BPM, ready to loop.
An AI agent building a marketing video needs a song with specific lyrics
Music-1.5 lyrics were capped at 600 characters. That's roughly one verse and a chorus. Any longer song required multiple generations and stitching.
With Music-2.6: 3,500 characters. Three full verses, pre-chorus, chorus, bridge, outro — in one generation. Or set lyrics_optimizer: true and let the AI write them from your prompt.
Pricing: 300 Sats Per Song
Music-2.6 costs more to run than 1.5. We tripled the price from 100 to 300 sats (~$0.30) and the quality more than tripled. Longer songs, precise control, better vocals — the output is worth more per generation.
Same model: no signup, no subscription, no API key. Pay 300 sats over Lightning, get an MP3.
API and Agent Access
The new parameters (is_instrumental, lyrics_optimizer, longer prompts/lyrics) are available on all three interfaces:
- Web UI at sats4ai.com/music — two new toggles for instrumental mode and auto-lyrics
- L402 API at /api/l402/generate-music — new JSON fields, same L402 flow
- MCP via sats4ai.com/mcp —
generate_musictool with all new parameters
Try Music 2.6
Specify BPM, key, and section structure. Get a full song in under a minute. 300 sats.