Phono Culture is a reference database of turntable cartridges and replacement styluses. This page explains where the numbers come from, how compatibility is calculated, and what we deliberately do not measure.
Technical specifications are taken from manufacturer datasheets and official documentation. The replacement stylus table is compiled from stylus makers' catalogues and from fitment confirmed by mounting dimensions. Every record passes human moderation before publication, so nothing reaches the database without being checked against a source.
Cartridge and tonearm compatibility is governed by the resonant frequency of the system. We compute it with the standard formula fr = 159 / sqrt((Meff + M) * C), where Meff is the effective mass of the tonearm in grams, M is the mass of the cartridge including hardware, and C is the dynamic compliance of the suspension.
The target window is 8 to 12 hertz. Below it the system picks up warp and rumble, above it the resonance intrudes into the low frequencies of the recording itself. The calculation is deterministic and reproducible, with no AI involved.
Sound DNA is a set of eight numeric metrics describing the expected character of a cartridge. They are derived from published specifications, not from instrumented measurement and not from listening panels. Treat it as a model for comparing cartridges to each other, not as a substitute for your own ears.
The opening paragraph of every cartridge page is assembled deterministically from database fields. Where a language model improves the wording, the result passes automated validation. Every number in the text must appear in the source data, otherwise the text is rejected and the page falls back to the template. This is what keeps invented years, prices and specifications out of the descriptions.
We do not measure sound instrumentally and we do not run blind listening tests. We do not sell cartridges or styluses, and prices shown are indicative, meant only to convey the class of a model. Where a manufacturer's own figures contradict each other, we keep the datasheet value and flag the discrepancy rather than picking the convenient one.
Write to cartz@phonoculture.com with the model and your source. We will correct it and note what changed.