1) My MOXF is connected to the console, everything works fine. When I set ASIO driver in Cubase to MOXF, I can hear high pitched buzz coming out of my speakres. This buzz is coming directly from the channel that MOXF is connected to, not from Cubase output channel (which is suspended at the moment). Strange. I can't figure out what is causing the buzz (power adaptor, modem.. etc..). Good news is that the buzz is not recorded. However, it's kinda annoying..
I remember the same problem with my MO6. Never found out what was causing the buzz..

Welcome to YamahaSynth. Hopefully, we can help you solve this issue...

Just some observations and then the solution. The high pitched zinging noise is a ground issue. Once the ground issue is solved, it will completely disappear. The reason you have trouble finding out what was causing it is you were likely looking in the wrong place. Firstly, it’s likely the buzz is coming out of the speakers (After all, the products themselves are not buzzing x the sound is coming from the speakers - if the products themselves are buzzing then you should power down, unplug and get help! :-)...
(no one blames the speakers)

the speakers alone do no buzz, neither do any of the devices, alone. Further frustrating the whole thing is when they are all connected together ...there is the buzz. So naturally the thought is something (some one thing) must be the cause.

The cause is actually the interconnection of the devices. Not any one thing.

If you remove the speakers the buzz goes away... but only because you cannot now hear it. I’m going through this to make the point... it is the interconnection of devices... and how they are using the electrical current. As a rough oversimplified analogy: in the digital world they are disagreeing about what is a 1 and what is a 0. Get them to agree and the noise goes away...

When there are multiple electrical devices connected there can be a differential in how they are using the current. Disconnect the USB cable, poof, the noise disappears. Reconnect the USB, it returns.

Ground noise traditionally is a 50Hz or 60Hz robust HUM... depending on where you live...but what immediately identifies this as a computer USB ground issue is the high pitched zinging sound.
Try to connect all devices to one electrical feed in the House. This can be logistically inconvenient, but if all devices are fed from the same power source, you can eliminate one major possible cause.

Increase the volume so you can hear it...then ask your computer to search for something on your hard drive... you can hear the noise “singing” and it changes pitch with more CPU activity. If your computer has an activity LED the noise will synchronize with the blinking of that activity.

Okay... it’s due to a disagreement between connected devices. The MOXF is connected via USB and it is, indeed the device asking the computer CPU to do work. We pretty much have the culprits (plural) - it’s when you have multiple devices interconnected that the issue shows up in your speakers (notice it is NOT recorded!) To blame the computer would be as wrong as blaming the device connected to the computer... it’s the combination.

They all are getting current from your wall. If you are on a laptop, you may notice the noise completely disappears when you run on batteries. (However, running on batteries may reduce your computer’s specifications, so you will want to find a proper electrical solution to the issue based on where you live.

Now, it would be irresponsible of me to just give you electrical solutions without knowing what type of voltage you are running on. Here in the USA we deal with 120V, in other parts of the world 100V or 220V - solutions that work on 120v might be disastrous on 220v, and vice versa. I cannot give advice on how to ground your computer properly to prevent that noise from traveling throughout your system... but know this, once you solve the ground issue this will remove this noise.

Because most ground noises of the type you describe, are simple - the solution is typically really simple.
However, any ground noise is an issue, and electrical gear is grounded for a reason. So err on the side of safety.

What you can do... consult proper electrical resources in your country.
It might be as simple as lifting the ground on the computer.
It could be as complicated as getting a stereo direct box to lift signal going to your speakers.
In rare serious cases you may need to filter the current at the wall. (I solved an issue once with 24 Macintosh computers interconnected in a lab, with Hum Eliminators that filter the current at the socket). Now that was some zzzzinging...

Solutions range from a few dollars to being very pricey... but consult electricians or other music users in your area. Your local music store (a great resource) may have solutions... trust me, you’re not the only one with ground noise.

Let us know. You can contact the Yamaha Customer Support in your area for regional solutions. Hope that helps.

2) When setting MOXF Master Volume fader higher than the line in the middle (probably unity gain) and hitting the keyboard hard, some sounds can be slightly distorted. The same problem was on MO6. I keep the Master Volume fader in the middle and it's fine, no clipping.

Any device can clip ... its when you send too much signal into the next stage of the audio chain.

Signal is like water being routed through a series of pipes. There are “valves” along the pipelines to control the amount of flow. If you send too much signal from one device into the input stage of the next, some water will spill (think of each drop spilled as a clip). The object of gain staging is feeding just enough signal into the next device without spilling any water.

Too little is almost as bad as too much; too little is when you have to use some kind of magnifier or boost in the receiving device - this can be bad because boosting could be noisy. Each device in the chain should be fed enough signal so it does not have to work too hard to boost it, and certainly you want to avoid sending in too much either!

Understand that the invention of meters are based on reality. The first meter was set as follows... they increased the signal until it distorted the receiving media. They marked that point and then some distance, well below that point, they put an indicator that shouts “Danger, danger Will Robinson... you are getting close to that point where we know Clipping occurs”.

There is no magic to it. They raised the signal until it distorted, then they back off on the amount sent. They left room between the actual distorting point (clip point) and the scaled the metering backwards from there. It was definitely a “learn by burn” kind of situation. The goal is to never clip (overload) the next stage of of the chain.

The height of the Fader might seem like a good measuring stick, but it is not. The Main Volume Slider of the MOXF does not affect the audio signal that is sent Out via USB. Not one bit. You could turn that all the way down - it does NOT impact the USB audio Out going to the computer. It only determines the analog output.

What does affect the USB OUT?
_ the Volume found by pressing [UTILITY] > [GENERAL] > TG (Tone Generator) This is the Master Volume of the entire synth and affects both analog Output (Main Volume) and digital (USB Main Volumej
_each Part’s PART VOLUME in cumulative and is a contributor to the Volume described above.

3) I really love S6 piano and its treatmens. It seems the waveforms are different, ex. "S6 Stretched ff St -" or "pan". What does the " - " and "pan" mean? I am curious. 🙂

The S6 is a Yamaha 6’9” acoustic piano that is renowned for its aged sound. There is some process used in treating the wood... it has a distinct character.
Yamaha (being the world’s largest manufacturer of musical instruments, and primarily a piano company) always provides both Stretched Tuned and Flat Tuned versions of the Sampled Pianos.

Stretch tuning is done to make the sound of an acoustic more vibrant... it involves tuning tuning the high end sharper as you ascend and the low end slightly flatter. (Talk to your piano tuner, they’ve been stretch tuning your acoustic piano for year!)
Flat tuned means it is tuned strictly to Equal Temperament.

Example, if you’ve ever layered a piano with an electric piano, and noticed that they are annoyingly out of tune in the top Octave, you can bet you selected a “stretched tuned” acoustic piano. Substitute the “Flat” version of the Waveform (Yamaha always provides both, why? Because Pianos is what we do and besides, it’s the right thing to do!)

“S6 Stretched ff St” translates to this Waveform (collection of samples) are of a Yamaha S6 acoustic piano, stretched tuned for solo work, “ff” is the double forte strike. (Yamaha provides soft, medium soft, medium, medium loud, loud sample sets... its fascinating... they have machines, designed by Yamaha, that can be calibrated to strike the Keys with precise pounds per square inch, to create the key strikes. They then get a piano technician to balance the response of the instrument to the precise strike force... it’s an amazing combination of machines and craftsmanship.... they provide these different velocity strikes because, like any percussion instrument, the harmonic content and behavior of the instrument changes the harder you strike it... the final “St” denotes this is a Stereo Sample. “Mn” would be a mono sample.

If you are not playing your MOXF through a stereo sound system, you should replace the Stereo Waveforms in your go to piano sound, with the Mono Waveform... Stereo cannot be properly reproduced in a single Speaker Single Channel System, so you should take the time to build the Mono version. Yes, it makes a difference. Why stereo? Because the information is different in the left channel from the right channel... exactly what your ear and brain use to locate sound sources... it’s more natural, it allows your brain to feel more like they are hearing a piano in a room more so than just a piano sound in a speaker.

Pan is short for “panorama”... on the old recording consoles you had a “panorama potentiometer” or “pan pot”. It refers to the Knob that controlled the stereo illusion. Stereo is the illusion created by using two speakers - one closer to your left than the right, the other closer to your right ear than your left.

You can create the illusion of someone walking across the room in front of you by “panning” the signal from hard left to hard right. The act of panning, is creating more resistance to the signal travel to one channel over the other. Like water the signal will take the path of least resistance.

To pan left you are actually increasing the resistance of the right channel... and as pan right you are actually increasing the resistance on the left. The illusion of a panorama stretching from horizon to horizon, is created by the placement of the speakers to the listener. I am found of saying... “Stereo, life itself is stereo” ... because we have two ears... I guess it’s best to say life is not mono, and stereo is better than mono... because life is really multi dimensional
But the left/right thing is so natural when listening to music... you never have explain to anyone where the best seats in the house are at a concert... you intuitively know it’s between the speakers!

Thanks for the questions.

Thank you very much for great explanation, Phil! Very helpful!!!!

I am afraid I can't do anything with the ground noise right now, I am unable to lift the ground on my Mac Pro. Most of my work is done via audio interface output, so it's not a big problem. I use MOXF driver only for recording tracks into Cubase..

All other devices (mics preamps, mics power supply, effect processors etc.) work fine, they do have ground lift switch.

Thank you very much for your help!