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I connected my p515 to my iPhone and I recorded my playing while video in iMovie.
I noticed the recording of the audio is directly from the piano such that I don’t need to layer the audio and video separately, which will save me hours of editing .. the only issue:
At random spots there is clipping of the audio , not because I’m playing loud, what would this be?

Clipping happens when the level is too high for the input. Do a recording and repeat one note pianissimo for 20 seconds and repeat the same note fortissimo for 20 seconds. If clipping happen only on the fortissimo recording, it means volume too high. If not, does the video have some drop out when clipping happen ?

I wonder if the iPhone performs any kind of normalisation/compression to the received sound? For example, when playing a pianissimo passage the volume may drop and the iPhone may automatically increase the recording level to compensate, resulting in clipping when louder passages are played.

This is just a guess - I could be completely off on this one!

Kind regards,
James
x

It’s seems irrelevant of how hard I strike the keys

Does the P515 have digital audio out or are you using the line outs through an audio interface?
Just curious how you are getting the audio into your iPhone.

I’m also interested in knowing this: built-in audio interface or line out?

We know that recording audio directly from the P-515’s audio interface into the iPhone is possible (great), so I assume that using the line out through an external audio interface and into the iPhone will also allow for audio recording. Am I right?

I assumed Jitin was using the P-515's built-in audio interface (USB out from the piano into the iPhone via a camera adapter).



Yes, that should be fine too.

Cheers,
James
x

Thanks, James.

This really simplifies things in terms of not having to deal with ‘synching’ audio and video from independent sources.

Yes this is really an awesome feature of the p-515. I have used it to and have not noticed any clipping. However I did have a glitchy cable that dropped connection to the piano that I replaced to a good one. The bad cable was one that came with a Samsung PC monitor and was new so was surprised. I have had no issues with the new cable.

Do you have any recordings of the clipping? Maybe I can do some more testing at home and see if I can replicate why you are experiencing.

I agree, it's a very nice feature for quick recordings.

However, I still believe it's useful to capture the audio (to a USB stick) as a separate WAV file for future use, rather than recording directly to a compressed format.

A/V syncing is not so complicated if your workflow is well organised

Kind regards,
James
x

I agree with you. When I'm good enough playing the piano I will most likely buy an NV5 and then I think my recordings might be worth saving

As of now, the best thing about the built-in audio interface is a one-cable solution between my laptop/iPad and P-515 for my practice software.

I will try post something later today to show my connection and the clipping part

P515 recording from iphone8

I improvised random stuff that is soft and hard attack but regardless of the attack there is clipping

I can definitely hear the clippings or to me it sounds more like interference from a faulty cable but I not sure.

Does it behave like this with one of the demo songs also or only when you play? When I’m home again on Monday I will check this. But haven’t noticed anything like this from the 2 times I tried it but didn’t play as long as you did.

FWIW --

The best way I've found to confirm that what _sounds like_ clipping, _is_ clipping:

a) Make a ".WAV" (uncompressed) recording on the iPhone (or whatever you use);

b) Import it into Audacity (on a PC) (there should be an equivalent for Mac);

c) Expand the time scale, and look at the waveform:

. . . . If there's clipping -- "flat-topping" -- , you'll see it.

I wouldn't use _any_ compressed format (AIFF, MP4, MP3, etc). There's too much chance of the compression algorithm changing the waveform.

I didn't hear clipping, but rather a static electricity discharge. My humble guess at this moment is that your cable is just a plain USB cable. Professional USB cables which carry audio always come with ferrite beads.

Get a USB cable with ferrite beads/chokes/coils.

Or you can get a couple of clip-on ferrite beads and equip your cable with them (maybe 1 bead is enough I don't remember):

https://www.amazon.com/Yarachel-50PCS-Noise-Suppressor-Diameter/dp/B0757H1SBZ?ref_=fsclp_pl_dp_4

It will very likely solve your issue.

Unlikely. The ferrite is normally to avoid emissions on the 30MHz to 1 or 2GHz range and we are talking about RF attenuation of microvolts(ish) to pass the EMC tests. USB does not carry audio, it is a digital interface (USB type C connector MAY carry analog audio and video also but they are distinct from the USB interface if memory serves). If there is some source of interference that is transient, adding ferrites will most probaly do no good.

That said, there might be quality issues with the cable that could cause drops and replacing the cable could fix it. Or the problem is elsewhere.

I said this based on my own experience. I used to own a MOX and when I was using a regular USB cable without ferrite my audio recordings had the exact same issue.

Yamaha synth keyboards come with USB cables with ferrite (MOX, MOXF ...).

Explain to engineers at Yamaha that you know better than them.

Oh just noticed this! It actually streams audio and who said that digital is not prone to data loss? It is digital but I am almost sure there are no parity bits in audio transmission.

Yes. Actually, digital is an abstraction: everything is analog, and as data rates increase (from 12Mbits/s to 480Mbits/s to 5Gbits/s) for each version of USB, things get more and more "analog" and cable quality is more and more critical. Did you added the ferrites to the USB cable or you bought one with they bult-in? If the latter, it is very likely the quality of the cable more than the ferrite beads did make the difference.