The first time I recorded my upright with a single condenser, I ended up with a track that sounded like someone playing piano inside a cardboard box. Everything below middle C was a single resonant thump, and no amount of EQ afterwards rescued it. The problem, I eventually realised, was happening before the signal ever reached the interface. One mic does not give you a second chance, so the placement you choose has to carry the entire tonal balance of the instrument. Get it wrong and you spend an hour fighting the low end in the mix. Get it right and the piano mostly mixes itself.
Here is what I have learned after several years of single-mic sessions, mostly on a Yamaha U1 and a friend’s old Challen grand, plus the occasional school upright that had no business being recorded.
Why the low end gets muddy in the first place
A piano radiates low frequencies in a way that is genuinely unlike most instruments. The fundamental of a low A on a grand sits somewhere near 27 Hz, and the soundboard amplifies everything above it in a wide, uneven pattern. Put a mic in the wrong spot and you capture a build-up of energy that has nothing to do with what the player hears.
This is the same problem producers talk about when they warn against multiple instruments crowding the same low band. If you record piano in a mix where a bass and a kick already live down there, and your mic placement has stacked the piano’s low-mid energy on top of them, you have created a frequency conflict that no compressor will fix cleanly. As one mixing write-up puts it, when instruments really fight for the same frequency range, equalisation will substantially damage the sound, and the better approach is not to make the mistake in the first place. For a single-mic piano, that means fixing it in the room.
So placement serves two purposes. It balances the piano’s internal tone, and it stops you from filling a frequency band you need to leave clear for other instruments.
The single most useful move: get the mic off the soundboard axis
Most people point the mic at the middle of the strings, roughly where the maker’s logo is. It feels sensible. It is almost always muddy.
Try this instead. On an upright, take the front panel off if you can, and aim the mic at the soundboard from the side, angled across the strings rather than straight at them. Move it towards the treble end a little, maybe a third of the way up from the bottom. The bass strings on an upright are short and close to the floor, and aiming directly at them collects a dense, boxy low end that gets worse with every inch closer you get.
On a grand, open the lid and position the mic over the middle of the soundboard, but back from the hammers. Point it down at maybe 45 degrees and rotate it slightly so it looks across the curve of the case rather than straight down the length of the bass strings. The difference between “pointing at the bass” and “pointing across the bass” is the difference between a woolly thud and an actual note.
Distance is a low-end control, not a reverb control
The instinct is that moving closer gets you more detail and moving back gets you more room. True, but incomplete. Moving closer also increases the proportion of direct low-frequency energy from the nearest strings and the soundboard, and that is exactly where the mud lives.
In practice I start about 30 to 40 cm from the strings on a grand and further back on an upright, then move away in 10 cm steps while the player holds a low chord. You will hear the point where the fundamental stops booming and starts sitting. That spot is usually further away than people expect. The trade-off is more room sound, and on a bright, reflective room you may not want that. But a little room tone is a better problem than an unmanageable low mid.
Angle before you EQ
If I could give one rule to anyone starting out: solve the boom with the mic angle before you reach for a high-pass filter.
When the mic faces the soundboard squarely, you get maximum low-frequency pickup. Rotate it ten or fifteen degrees off-axis and you lose some of that energy while keeping the body of the note. On a cardioid mic this also shifts the proximity effect, which is one of the biggest culprits in a boomy close piano sound. Backing off a few centimetres does the same job.
Only once I have the angle and distance as good as the room allows do I open a surgical EQ. A narrow cut, somewhere around 150 to 250 Hz on most uprights I have recorded, with a Q of 3 or higher, targets the resonance without denting the neighbouring frequencies. That is the same principle used in a careful mastering chain: narrow cuts for problems, broad moves for musical choices. Keep the surgery tight and let the broad tonal shaping happen later.
What not to do with the one mic
Do not add a second mic to fix the low end unless you are prepared to deal with phase. I have watched people stack a close mic and a distant mic hoping the distant one would “add air” and end up with a hollow, phasey result that is worse than the original mud. With one mic, commit to the placement. If the low end is still wrong, move the mic again.
Do not layer two piano takes to get a bigger sound. Layering several low-quality sounds does not create a high-quality instrument, and in the low frequencies a second take is another source fighting for the same band. Fewer layers and a better single performance beat that every time.
And do not reach for a multiband compressor on the way in. If you find yourself compressing only the low-frequency band to tame a boom you recorded, the boom was a placement error. Fix the source.
A practical starting sequence
This is the order I work in now, and it usually takes fifteen minutes.
- Have the player hold a sustained low chord, ideally something with a strong bass note plus a harmony above it.
- Place the mic where you think it should go and listen through headphones.
- Rotate the mic off-axis in small steps until the bass note stops booming and starts sounding like a pitch rather than a thump.
- Move the mic back in small steps until the low end sits and the room tone is acceptable.
- Play a full piece. If the balance holds across registers, you are done.
- Only then apply a narrow corrective cut if one specific frequency still rings. A filter with a Q of 3 or above keeps the fix local.
Track a rough take before you touch any plugin. I have talked myself out of good placements because a little EQ made the headphones sound nicer, then regretted it when the raw file turned out to be the problem.
What “fixed” actually sounds like
A well-placed single mic gives you a piano where the low end is present but not dominant, the mids have definition, and the high end is whatever the room and the instrument give you. It will not be a glossy studio sound. It will be honest, and it will fit into a mix without needing rescue work.
The trade-off is real. One mic means no stereo image, no ability to blend close and room, and less forgiveness in a bad room. If the room is reflective and small, a single mic will amplify that. The honest answer in that case is that placement helps, but the room is the real bottleneck, and moving the piano or treating the space will do more than any further mic tweak.
Still, for a music teacher recording students, a songwriter tracking their own parts, or anyone working with one good condenser, placement is the whole game. Angle, distance, and patience. The low end sorts itself out once you stop pointing the microphone at the place it lives loudest.
