Sound is distorted at certain frequency / volume what would cause this?

Could be a few things, most simple the Tubes, and or biasing, I have had a few amps that certain notes or chords would cause harmonic distortion within the tubes, and the tubes where good? Another possibility is the output transformer? Sometimes when they are failing the volume varies... hope this helps?

Experiencing discomfort or pain in your ears while playing your Technics digital piano is not a normal occurrence and could be a sign of an issue that needs attention. There are a few potential reasons for this phenomenon:

1. Frequency Range: It's possible that certain frequencies produced by the piano are resonating with the natural frequencies of your ears or the surrounding environment, causing discomfort. This could explain why you feel it more in specific ranges of the keyboard.
2. Acoustic Properties: The sound produced by the piano might be reflecting off nearby surfaces or causing standing waves in the room, which can create resonances that affect your ears.
3. Volume Level: If the piano's volume is too high, it could lead to discomfort or pain in your ears. Even if the volume seems moderate, it's possible that specific frequencies or overtones are causing issues.
4. Headphones: The fact that you don't experience this issue when using headphones suggests that the problem might be related to the piano's built-in speakers or its interaction with the acoustics of your environment.
5. Electronic Components: There could be a malfunction or interference in the piano's electronic components that is affecting the sound output in a way that causes discomfort.

To address this issue:

1. Volume Control: Try lowering the volume of the piano and see if the discomfort lessens. Gradually increase the volume until you find a level that doesn't cause discomfort.
2. Room Acoustics: Experiment with placing the piano in different locations within the room to see if it affects the sensation you're experiencing. You could also try using soft materials like curtains, rugs, or acoustic panels to dampen reflections and standing waves.
3. Equalization: If your piano has an equalizer or tone control settings, try adjusting them to see if it reduces the discomfort.
4. Professional Inspection: If the issue persists, consider having the piano inspected by a technician to check for any electronic or acoustic anomalies.
5. Expert Advice: If none of these steps resolve the issue, it might be best to consult with an audiologist or a professional musician who has experience with piano-related sound sensitivities. They might be able to provide more personalized advice and recommendations.

Your health and well-being are important, so it's essential to address any discomfort or pain you're experiencing while playing your digital piano.

Guitar amps have preamp sections (think unpowered audio mixer) and power amp sections (Crown rack-mount amp). An excellent way to isolate audio problems if amp is still producing audio is to check the preamp out (line out). Preamp output distorted = preamp failure. Connect MP3 player to "Power Amp In"...sound distorted = power amp failure. In your case the latter is the case as your "line out" is clean. Also test each speaker for clear sound as speaker cone damage from being overpowered is fairly common. At 300w. I'll assume the failure was not from cranking the volume to loud but a shorted speaker or speaker wiring could zap the power amp in an instant.

You can put just about any instrument through any amp. The difference in sound will be whether or not that amp was designed for the particular frequencies of that instrument. Also whether or not the speakers you are using are designed for those frequencies. When playing bass you need speakers designed to carry low frequencies (40 - 400 hz); mid-ranges and tweeters don't cut it. Set your instrument volume on the guitar at 70 - 90 % to get the most signal from the instrument. Set output volume on the amp at 50 - 70 %, then adjust gain on the amp to get required sound level. You're not likely to blow the amp, but you could blow the speakers if the amp delivers more power than the speakers can handle. With a micro amp check the output rating. It's possible you may not have enough power to get the sound you want and as you turn up the gain the sound will distort.

Please add more information to improve help, does the amp just distorts in that particular note or teh entire sound is distorted? does the amp distorts at low volumes?

Numbers on volume controls mean very little as there are too many things that affect the level. If you are really driving it hard you may be causing the amp to go into thermal limiting. This is a 100 watt amp so there is a limit. The sound level from it probably can easily exceed legal limits. You should get and use a sound meter. If the amp can create 100 Db that is all you need. If you stay in that environment over a few hours, you are a candidate for hearing aids in the future. I know several musicians that are in this condition and now are wrecked. Remember that loud does not equate to QUALITY... Your group should have a sound level meter and with that you can tell if the amp is performing as it should. One thing to be careful of is high frequency feedback, even that above what you can hear that heats up the amp with frequency output you are not using. Make sure your guitar cannot "Hear" the amp. Also be careful of boosting the high frequencies. Also be careful of large bass pulses that you can see drives the speaker cones to the limit. If the cones move too far, the voice coil leaves the active magnetic area causing excess current and amp heating. Make sure there is free airflow around the amp and especially the heat sinks.

CHECK VOLUME CONTROL BUTTON.

If you are driving the speaker too hard it will pop. This caused when the voice coil is driven mostly beyond the pole pieces of the magnet. Without the magnetic field the back EMF of the voice coil drops off and the current shoots up. The voice coil can't move farther so there is a discontinuity of movement which causes a pop.

200 watts is a lot to put into a 12 inch speaker so you have to be careful to not drive low frequencies at excessive volume. It is both very hard on the amp and doesn't do the speaker any good either.

If you want loud lows, you should get a subwoofer of at least 15 inch speaker to handle the lows.

Just a thought:

If you used the speakers with another amp and they still make noise when you play certain frequencies, then it is obviously a problem with the speakers or the cabinet - it could be a mechanical resonance in some part of a speaker / cabinet, something like a loose screw or a nut, loose protection mesh on the speakers that resonates at certain frequencies, possibly a bad speaker or a speaker membrane...

Also, you might want to check the pickups on your guitar, see if the pickup core slug under the A string is much closer to the string than the other slugs so it is either picking up too much signal and distorting it or the string might be touching the slug when you play it and cause noise, also see if the string is touching something else when it vibrates...

good luck

3rq8 (Triarcuate)

The distorted and low volume output plus noise is usually caused by using the wrong power supply adapter. The Alesis SR-16 takes a 9V "A/C" supply not "DC". The A/C supply provides a negative voltage swing which wouldn't exist with a DC supply. So check and make sure you have 9V A/C output supply not DC.