Ask those with experience in placing microphones for piano recording and the chances are you will hear of it being an art form rather than a reproducible technique.  There is truth in that – as the variables are endless. On the other hand there are some tried and tested methods, or rather some useful guidelines, for placing various forms of cardioid phantom-powered condenser microphones.

UPRIGHT PIANO
Our experience with an upright piano is demonstrated in this  Chopin and Bach link. We used three microphone pairs and selected a mix of each in the final editing. The open lid in an empty church was a bit heavy on the echo though.

GRAND PIANO
For jazz groups and for gigs where instrument sound separation is required for later mastering, close ‘miking’ is essential – but might not be best for smoothness and ambience suited to quieter or classical music situations. Under those conditions, a pair of mics at a half to one meter distance (fully open lid) will give very decent results.  However, if there risks to be people noise, then closer placement might still be necessary.

Here is a set-up which we used for a 2017 jazz group recording – a single pair of Neumann condenser microphones. Actually the sound was excellent; results here. Rules of thumb: place microphone pair above where the high and low strings cross – spread apart for better width pick-up – raise for more body.

A Swiss Radio (RTS/Espace 2) recording we attended at studio 15 in Lausanne – Enrico Pieranunzi trio – piano with 8 mics.  (this blog update, 24Oct2017) :-

DPA’s “d:vote” microphone stereo kit for piano — Esteban Castro at Montreux and manufacturer’s image :-

At the AMR/Sud des Alpes concert room with the Grupetto :-

An in-piano microphone experience (2014): straight pair Audio Technica.

Another update from Fête de la Musique 2019 – we saw live Léo Tardin (winner of Montreal Jazz Festival piano prize 1999) and took photos of the microphones inside his piano.
He plays solo, improvisation on his own compositions – music and more info here.

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