When I was in my first years learning violin I often heard that I couldn't use a regular old tuner to tune my strings. The explanations were vague but all ended up recommending to use my ears...
Now I understand why, but I digged enough to know how to use a tuner to tune a violin as well (something I like to teach to beginners)
So, to tune a violin you need a tuner that shows hertz in real time (cents offsets is also possible but won't explore here)
- E 660 (1200)
- A 440 (880)
- D 293.3 (586.6)
- G 195.5 (391.1)
Note: D's .3 and G's .5 are recurring decimals.
Why?
Our ears favor consonance by default. The octave is the most consonant but infertile in the sense that you can't build scales with it. However, the perfect fifth is the most consonant sound that can be used to create scales.
And indeed multiple cultures chosen scales align perfectly with the fifth. Scales of 5 notes, 7, 12, etc. In the west we stopped at 12 and haven't gone further.
How do you calculate a perfect fifth. Well you have to:
- multiply a frequency by 3 and divide by 2 to find the fifth above
- multiply a frequency by 2 and divide by 3 to find the fifth bellow
The History of Violin Playing From its Origins to 1761 and Its Relationship to the Violin and Violin Music Oxford University PressSemantic Scholar
tl;dr: Instruments such as the violin have a different tuning than other instruments such as guitars and pianos...