Sound speed in tonewood species
Reference Values
The values below are ranges observed on real samples measured by LucchiCremona over more than forty years of practice. They are field guidelines, not absolutes: every batch of wood has its own story. For an extended list with more species, download the complete MIN-MAX sheet (PDF).
Main species
All values below are longitudinal speeds (measured along the wood fibres), unless otherwise noted. For two-dimensional soundboards — such as violin tops — the transverse speed (perpendicular to the fibres) is also needed, typically much lower.
| Species | Longitudinal speed | Notes |
|---|---|---|
| Spruce (soundboards) | 4350 – 6300 m/sec | Transverse speed: 700 – 2100 m/sec |
| Maple (backs, ribs, necks) | 3300 – 5200 m/sec | — |
| Pernambuco (bows) | 4350 – 6130 m/sec | See practical thresholds below |
| Ebony (fingerboards, fittings) | 3100 – 4000 m/sec | — |
Pernambuco for bows — practical thresholds
Pernambuco is the species on which LucchiCremona has the most consolidated experience. The thresholds below relate the Lucchi value to the acoustic and mechanical quality of the finished bow stick, and are the reference with which traders and bow makers worldwide discuss the price of a batch.
| Range (m/sec) | Bow stick quality |
|---|---|
| < 5000 | Not usable for bows of acceptable quality. |
| 5000 – 5200 | Soft bows, lacking strength and elasticity, dull tone — suitable for entry-level study. |
| 5200 – 5500 | Medium-good, fair responsiveness, still dark tone — good-level study bows. |
| > 5500 | Sought-after material, bright tone rich in harmonics, snappy — concert and high-level study bows. |
| ≈ 6000 | Rare values — all acoustic and mechanical qualities at their maximum. |
The thresholds apply to whole bow sticks (intact wood, before processing). For already finished bows, the reading is systematically lower due to the mortise for the frog and the hole for the button: a percentage correction is applied to estimate the original value of the wood — see Evaluating finished instruments.
How to read these tables
The values are guidelines, not verdicts. Three practical considerations:
- Moisture matters. A freshly cut piece (moisture ≈ 40%) returns appreciably lower readings than the same piece once seasoned. On spruce, direct experience indicates approximately "−1% moisture ≈ +1% Lucchi value". See Treatment verification.
- Direction of measurement matters. Probes must be oriented along the fibres for the longitudinal speed, perpendicular for the transverse speed. Do not compare numbers taken in different directions.
- The species must be declared. "5500 m/sec" is an excellent value for Pernambuco but very low for spruce soundboard wood. The number means nothing if separated from context.