How to prepare your audio for lathe cutting.

If you want the short version before reading the full guide — here are the specs to hit.

Send a stereo WAV file. Specifically: 24-bit, 44.1 kHz, stereo interleaved. This is the format the cutting chain expects and it preserves the full dynamic and frequency information of your master.

Why not MP3 or AAC?

Lossy formats like MP3 and AAC throw away audio data using psychoacoustic compression — information your ears supposedly won't notice in casual listening. On vinyl, played back on a decent stylus and amp, the artefacts become audible. Pre-ringing, smeared transients and high-frequency mush that sits under the mix on a phone speaker will surface on a lathe cut through a proper system. Send the lossless source, always.

What about 32-bit float or 48 kHz?

If your DAW session runs at 48 kHz or 32-bit float, export to 24-bit / 44.1 kHz before sending — most DAWs do this in the export dialogue with a high-quality dither and sample rate conversion. There's no benefit to sending a higher resolution file than the cutting chain requires, and it adds file size for no reason.

One file per side

If you're cutting double-sided, send two files: one for Side A and one for Side B. Don't bake gaps between tracks into the file — if there are multiple tracks on a side, send the full continuous side as a single rendered file. Gaps, locked grooves and runout are handled at the cutting stage.

Vinyl has a fundamentally different relationship with loudness than digital. On a stream, making your master louder is trivially easy — hit a limiter, crush the peaks, done. On vinyl, loudness comes from groove width and depth: the louder the signal, the more the stylus has to move, the wider the groove needs to be. A heavily limited master with no dynamic range forces the groove to be constantly at maximum excursion — there's no room to get louder on the peaks because it's already at the ceiling everywhere.

Target: –14 to –16 LUFS integrated

This is the range where vinyl cutting works well. It gives the cutting head enough headroom to encode peaks accurately without the groove walls colliding, and enough signal to cut a loud, clear record. A well-cut vinyl record at –14 LUFS will sound louder on a turntable than a streaming master at –9 LUFS through a HiFi — because the dynamic range is preserved and the transients hit properly.

True peak ceiling: –1.0 dBTP

Set your true peak limiter to –1.0 dBTP. This provides a safety margin for any inter-sample peaks that emerge during the digital-to-analogue conversion in the cutting chain. Anything above 0 dBFS true peak is a problem; –1 dBTP is conservative enough to be safe.

Low frequencies are the most demanding thing a cutting stylus has to encode. A loud kick drum at 60 Hz requires significant lateral groove movement every 16 milliseconds. Pack too much bass into tight grooves and the stylus physically collides with the adjacent groove wall — a groove collision, which sounds like a loud crack and can damage the stylus.

High-pass filter below 30 Hz

Apply a high-pass filter at around 30 Hz before sending your master. Sub-30 Hz content is inaudible on almost every consumer playback system but takes up groove space. Removing it doesn't change the perceived sound — it just gives the cutting head more room to work with.

A 24 dB/octave high-pass at 30 Hz in your DAW is sufficient. Most mastering EQs have this as a standard option.

Make bass mono below 150–200 Hz

Stereo bass causes vertical groove movement (as opposed to lateral). Vertical excursion requires much more groove depth and is a common cause of stylus mistracking on playback. Making bass content mono below around 150–200 Hz is one of the single most effective improvements you can make to a vinyl master.

In most DAWs this is a mid-side or bass mono plugin away. In Reaper you can do it with a combination of JS plugins or ReaEQ with the mid-side routing. Most mastering suites have a dedicated bass mono tool.

What about dub, drum and bass, techno?

Bass-heavy genres work fine on vinyl — including on lathe cuts with the Nebula head — but they need the LPI set generously (lower LPI, wider grooves) which reduces the achievable playing time per side. A 12-bar dub plate with a heavy sub kick will cut beautifully on a 7" at 45rpm. An hour of bass-heavy DJ material will not go onto a 12" without significant compromise. For bass-heavy material, the format and track length constraints are tighter — factor this in before ordering.

More music per side means tighter grooves, which means less room for amplitude, which means less bass and less volume. This is a direct physical constraint — it doesn't vary by cutting service or equipment.

Practical guides by format

If your material is longer than these guides, get in touch before ordering. It's often possible to work within the constraint with some adjustment — but it's better to know before the disc is cut.