Hi all,

I recorded some piano and there is a strange effect in this very short clip on the 3rd note (and some on the 2nd).

It is "pumping" sound or perhaps I should say it resembles a "slap back". Don't know.

There are no effects whatsoever. I double checked the R-44 and no effects where turned on.

The chain is a pair of Mojave 101 Fets - Great River Pre (MP-2) - Mytek ADC - Roland R44.

Any ideas? You may need to turn it up a bit.

Thank you in advance.

Hi Shosty,

I am a piano technician. It sounds to me (other than the too-loud pedal noise) like it's within the normal range of tonal variation that we find in the capo-bar area (about an octave above middle C and the notes above that) of a Steinway (or pianos with similar treble design).

The initial attack of a piano note is somewhat chaotic; all three strings of a unison will often have varying pitch envelopes (yes, piano notes change pitch during their duration), and the three strings will take some time both to settle into more regular oscillations and to synchronize (somewhat) with each other via the displacement of the bridge (the shared bridge motions can encourage them to lock into a stable phase relationship). During that phase alignment, the strings also sometimes change their tonal character as the initial vertical displacement of the wire transitions into a horizontal pattern; that can be perceived as a swell.

Also, in the melodic region of your example, sustain becomes shorter, and minuscule irregularities in the wire and in the terminations of the wire (the occasionally loose bridge pins and the always somewhat soft capo bar bearing surface) often cause a particular string to be unable to settle into a stable pitch and instead settle into a repeating "vibrato" that piano technicians call a "false beat." Such strings may not ever lock into a stable phase relationship with the other strings of that unison, leading to amplitude swelling and diminishing with the changing phase relationships between the strings.

In addition, and maybe most importantly, that's the region where the front duplex starts; those are shorter resonating areas near the front of the string; energy leaks to the front duplex and back to the speaking length via rocking motion in the wire. The purpose of the front duplex is to increase the length of sustain in that region (by using energy constructively rather than wasting it by damping it with cloth and a severe angle change, as happens in the agraffe sections below), and also to add a complex character to the tone.

I think those are the factors that create the effect you're hearing. Piano technicians (and advanced pianists) refer to this tonal character as "bloom," and it is highly desired more often than not (though, of course, tastes vary). In fact, some piano technicians will purposely very slightly mis-tune the unisons in that region to increase the bloom (by delaying the arrival of a stable phase relationship).

Most Bösendorfers have a simpler, cleaner, clearer treble tone; proponents of that tonal ideal often prize them for those attributes (it's quite beautiful in its own way). Steinway has among the most complex treble tone, and I believe that it is a major factor in their success.

In fact, pianists sometimes complain about the complexity of the Steinway capo-area tone that they hear when they're playing (since it's so close to their head), but the same pianist will usually love the tone as a listener several or many feet away. In the hall, it adds a beautiful shimmer and liveliness to the tone that greatly contributes to the pianist's ability to create the convincing illusion of legato ("true" legato is not possible on a piano in the way it is in a wind or bowed instrument).

Of course, our mics when placed close will sometimes capture an annoying wavering or "zinginess" in that region. Such is life with pianos. If the piano technician labors mightily to remove as much of that as possible, a shorter, somewhat boring tone may be the result.

JoeDeF, thank you immensely for your response! It is on the one hand very educational and on the other a bit of a relief as I was concerned I had some phase issues going on due to mic placement.

But it is interesting how you describe this phenomena because I was thinking it sounded a bit like vibrato. In a large hall in particular I can see how that would contribute to the "bloom" you refer to.

What is also interesting is that you mention the wavering being picked up by close micing. In this example the mics were about 6 1/2 feet away but higher than I usually place them (about 9 feet up) and it is the first time I have heard this effect (at least so blatantly). I was expecting to pick up more detail at the higher placement, which I apparently did (although the sound was too thin for my liking).

Thank you again for the detailed response. It is much appreciated!

Thanks JoeDeF for the detailed reply !

As a pianist, it is always very frustrating to find an instrument that does not have this bloom.

Besides the build, I find the tuning (mostly), maintenance, and not least the pianist has a big influence.

Tuning the 3 strings just (not) right so they find each other in the right moment ?
The way a good pianist strikes the keys and uses the sustain pedal.

Anyway, this bloom is indeed highly desirable, because it is almost the only thing which actually helps the notion of "legato" on a modern piano. Some halls have a similar response, which can help as well.

I am always amazed how a good Steinway D can sing in the right hands, and in the exact conditions (+same music) can sound extremely boring and dry with another pianist (and/or tuner).

Curious minds want to know: does moving the mic(s) further from the Steinway allow the 'bloom' to blend better? What was the position / distance of the Mojave 101s in this instance? Fascinating stuff!
Edit: I read where Shosty says the sound became thinner at farther away. More detail - were you using the omni capsules? Thx.

Yes, those are the omni capsules. I notice it got significantly thinner at 9 feet up than 7 feet (but clearer and more detailed).

I have another recording of the piano on a different day with the mics at 7 feet high and 10 feet back (warm sounding) and getting more hall. I will listen later on to see if the "bloom" is there.

This is so interesting to me because I've never read anything regarding mic placement and capturing the "bloom" of a piano before but based on what JoeDeF and Yannick are saying, it seems to imply that a mic placement that captures sufficient hall would be necessary to for this "bloom" to have full effect. However, I notice quite a few classical piano recordings have a close and detailed approach to mic placement (a bit of a "head in the piano" sound).