Vinyl Cutting
A vinyl cut is limited by side length, low-end motion and high-frequency heat, so it needs its own master.
Related
Vinyl is not a 24-bit WAV in another container. The cutter has to move a groove in limited time: too much low-frequency amplitude and the stylus jumps, too much high-frequency energy and the cutter head overheats, too long a side and the grooves narrow and the level drops.
Three physical limits
Side length first. A 12-inch side at 33 rpm usually stays between 18 and 22 minutes; longer means tighter grooves and less available level and high end. Low end second. Out-of-phase bass makes the cutter head travel too far vertically, so everything below 100 Hz is usually summed to mono, or at least checked for phase. High end third. Dense sibilance, distorted guitars and heavily compressed cymbals heat the head, and the groove plays back rough.
Cut a separate master
| Problem | What happens at the lathe | What to do in the master |
|---|---|---|
| A side over 22 minutes | Narrower grooves, lower level | Split the side or change the order |
| Out-of-phase bass | Excessive head travel, jumps | Sum below 100 Hz to mono |
| Dense high end | Overheated head, distorted playback | Ease 8 to 12 kHz, reduce clipping |
| Overall too loud | No headroom for the cutter | Leave 3 to 6 dB peak margin |
| Very long tails | Not enough groove spacing | Shorten tails or resequence |
Checks before cutting
Ask the plant for its specs: speed, side length, half-speed or DMM. If an album exceeds two sides, decide between a double LP and cutting a track before work starts; changing the order later means a new test cut. Then make a separate vinyl master: less loud than the streaming version, more dynamics kept, bass summed, highs gently softened, and enough room at the end of each side. A test cut must be heard, especially the inner groove of the last track on each side. The plant usually wants a running-order sheet with side timings and fade points, and sending it with the master saves a round of questions.
What not to do
Do not send the streaming master straight to the cutter, and do not encode lossily after cutting. Vinyl has a different noise floor and dynamic feel, so match loudness before A/B. Inner-groove distortion, jumps and high-frequency heat rarely respond to EQ; severe cases mean recutting or changing the running order. Vinyl suits a complete album and a release with ceremony, not a single whose only goal is loudness.
Listen in the library
All tracks from midicn-lib — inline badge is the license tier (C1 commercial / C2 non-commercial / C3 study only).
Along the same line
Sources
- Katz, Bob，Mastering Audio（Focal Press）— 黑胶预母带、刻片电平与低频处理章节。
- AES（Audio Engineering Society）关于黑胶刻片与纹槽几何的公开论文 — 刻片头运动与高频过热的依据。
- RIAA 均衡曲线（Recording Industry Association of America）— 刻片与回放的低频补偿口径。