The master volume have a sond tha when it inn high become to noise and disturbing my ears

The short answer is yes. You didn't tell us what make/model/speakers, but if it was really high volume you may hsve blown a speaker. Of course, if you let it get out of hand you can damage your ears.

"Overdrive Channel: high frequency noise as the gain and volume are increased."

This is the expected result, you are experiencing feedback. Try turning the "Contour" knob all the way to the left and turn down the tone knob on your guitar.

Sounds like Tube Microphonics to me...
Change the 12AX7 (I guess) for that channel for starters.
If not, some condenser went crazy.

No, that will not help. The his is a function of the receiver NOT receiving a signal from the transmitter as they apparently do NOT have a "squelch" circuit to mute the receiver noise when no signal is being received. The noise level when no signal is received is pretty high and apparently the volume control is not enough to reduce the hiss.

To solve this, LEAVE the transmitter ON and make yourself a switch at the receiver. DO this using one of those little in line lamp switches that fit on zip cord. Make one on a short length of zip cor with mating connectors to fit the received jack and the headphone plug. Don't worry about unshielded wire as the impedance is very low. Then you use this switch to mute the headphones when you want to. There are other switch types you can use, I am just suggesting what might be readily available to you.

Sennheiser SHOULD have include a mute switch on their unit as turning the power off on the receiver would be a pain. They could have used a volume control with switch to kill the audio line out... simple solution... oversight on their part.

There is not enough info here to provide a complete answer, but let me give you some background:

There will always be some hiss. This is due to general amplification where a small amount of noise is amplified along with the general signal. In most cases, the signal is strong enough to overpower any noise that is present (vocals in your example). This noise should not be that noticable in normal cases. If there is an automatic gain control in the line, this could account for it as with "silent" times, the gain will automatically be increased potentially to the degree where the noise is noticable.

Barring that scenerio, if the input signal is too low, the overall gain necessary to produce reasonable volume at the speakers will also be such that the noise is noticable. In order to track this down, please provide details about the current setup including:

1) Microphone make and model being used
2) Input being used on the mixer
3) Gain level being used for the mic channel
4) Gain level being used at the master level.

Dan

Hiss is a problem of statistical noise in electronic devices due to the laws of physics plus circuit design.

One thing to do is to improve the signal to noise ratio (SNR) by properly setting gains. It is POSSIBLE that the IEM's you are using are too low impedance for the receivers resulting in you having to use excessive gain at the receiver. Your receiver gain control should not have to be above 60% of the way up. If you are above that, the ear buds are probably lower impedance than the receiver is designed for... and remember the manufacturer will LIE on the capability of the thing they are trying to sell.

The receiver is speced at 32 ohm drive... IF your ear buds are less than that impedance, they are NOT suitable. Conversely if they are too high, thaat will ALSO cause you to turn up the receiver gain too much and result in poor SNR.

You want to make sure the transmitter is being driven at line level so receivers get adequate input audio so gain doesn't have to be run too high.

If the organ has a reverb spring "tank" in it, that is likely where the spring sound comes from.

The initial noise is likely due to the initial unbalance of the power audio amp.

Lesser organs don't disconnect the speakers till the amps attain balance so the inrush pulses the speakers..

secret code of sond samsungm620

If it clips, then LIKELY you are driving it too hard.

When it goes into clipping, it truncates the waveforms and will create a disturbing NON musical noise.

Line 6 stuff is NOT noted for reliability, so take it easy and hold the volume below the clipping level. The light coming on means it is protecting itself from overload.

Sounds like your master volume is turned up too much. The channel volume will make the squealing go away(caused by high gain and humbuckers). The best thing to do is dial in your favorite presets and change the channel volume to the correct level with the master volume where you usually keep it. I use my Spider Valve at master volume at about noon and the channel volume between nine o'clock and noon. Let me know if this does not solve the problem......