45rpm vs 33rpm. Which should you choose?
Speed affects cut level, groove width, side length and tracking. For most releases the answer is straightforward — this guide explains why, and what to do when it isn’t.
What speed actually changes
At 45rpm, the groove moves past the stylus faster than at 33rpm. That faster movement means the same audio information gets encoded into a physically wider groove over a greater length of the record. More physical space means more room for detail — the stylus has an easier job tracing the groove accurately, especially at high frequencies and loud passages.
The result is a louder, better-tracking cut with more headroom and more high-frequency clarity. The trade-off is running time — faster speed means fewer minutes per side at the same diameter.
The practical numbers
| Format & speed | Recommended max/side | Absolute max/side |
|---|---|---|
| 12″ at 45rpm | 7–8 min | ~10 min |
| 12″ at 33rpm | 11–13 min | ~18 min |
| 10″ at 45rpm | 5–6 min | ~7 min |
| 10″ at 33rpm | 8–10 min | ~12 min |
| 7″ at 45rpm | 3–4 min | ~5 min |
| 7″ at 33rpm | 5–7 min | ~9 min |
Maximums depend heavily on programme material. Bass-heavy, loud audio needs more groove space and reduces running time. Quieter or less bass-heavy material can push further. Running time and quality in detail →
When to choose 45rpm
- Dance music, DJ tools, club records. The cut level advantage is significant. A 12″ at 45rpm is louder and more dynamic than the same track at 33. On a club system the difference is audible — better low-end punch, cleaner highs, more tracking stability.
- Short sides. If your track is under 7 minutes, go 45. There’s no meaningful benefit to cutting it at 33.
- High-frequency content matters. Detailed, bright or complex audio cuts better at 45. The wider groove handles transients more accurately.
- You want the loudest possible cut. 45rpm gives you more headroom. If cut level is a priority, the speed choice is straightforward.
When to choose 33rpm
- Longer programme material. An album side, a continuous mix, anything over 10 minutes — 33rpm is the practical choice once you’re beyond what 45 can accommodate cleanly.
- Running time is more important than cut level. If the material is relatively quiet or not bass-heavy, 33rpm at moderate length sounds fine. The loss of cut level matters more when the source is loud and dynamic.
- Multiple short tracks on one side. An EP with three or four tracks that together exceed 8 minutes — 33rpm keeps them on one side.
The inner groove problem gets worse at 33rpm. Longer sides push audio closer to the label, where groove geometry makes accurate tracing harder. Placing your most demanding audio at the start of the side (outer groove) is good practice regardless of speed. Inner groove distortion explained →
The short answer
If your side is under 8 minutes and the music is at all dynamic or bass-heavy: 45rpm.
If your side is over 10 minutes, or you need to fit more music than 45rpm allows: 33rpm.
If you’re unsure, describe the programme and side length when you submit your order and it can be discussed before cutting.