Hi I am new to the forum.
I have a question in relation to a noise running at about 150HZ from my pre amp. It is on the right channel.
The same noise on the left channel but to a much lesser extent and left channel runs at 110HZ.
It occurs all the time. I have changed tubes and noise still present.
it is unaffected by volume of unit. Meaning notwithstanding volume level the noise remains constant and at the same audible level. It does not increase in volume.
It is present even though nothing is attached to the pre amp.
I have uploaded the actual sound.
I'd be grateful for any suggestions as to what is causing this sound, and how to fix it.
Thanks
I have a question in relation to a noise running at about 150HZ from my pre amp. It is on the right channel.
The same noise on the left channel but to a much lesser extent and left channel runs at 110HZ.
It occurs all the time. I have changed tubes and noise still present.
it is unaffected by volume of unit. Meaning notwithstanding volume level the noise remains constant and at the same audible level. It does not increase in volume.
It is present even though nothing is attached to the pre amp.
I have uploaded the actual sound.
I'd be grateful for any suggestions as to what is causing this sound, and how to fix it.
Thanks
Did you built the amp yourself? Post the schematic and assembly pictures (wiring). Without that it will be difficult to figure out the problem.
That is a the sound of cellular interference. So probably picking up a mobile phone RF signal or basestation.
I agree with Baudouin0, it sounds like a mobile phone or similar radio interference.
Regards, Gerrit
Regards, Gerrit
Do you use a metal case? Do you have a mains filter? Is your case grounded with your power cord?
Regards, Gerrit
Regards, Gerrit
I hear this kind of noise if I put the preamp too close to my SACD player. Try to move the preamplifier in a different place and check if the noise changes.
Hi,
Thank you for all your suggestions. They have been very helpful.
The Pre Amp is housed in a solid (6mm) metal casing. It appears the problem is now solved.
I had the Pre Amp connected to an AC Regenerator which the DAC and AMP were also connected to.
I have connected the Pre Amp (via a surge protector) to the same wall power socket used by AC Regenerator (same line).
The Oscillation noise is now gone.
Still a very slight buz, but I think that is coming from the Tubes (6922 x 2).
Thanks again, I am very grateful for your advice.
Thank you for all your suggestions. They have been very helpful.
The Pre Amp is housed in a solid (6mm) metal casing. It appears the problem is now solved.
I had the Pre Amp connected to an AC Regenerator which the DAC and AMP were also connected to.
I have connected the Pre Amp (via a surge protector) to the same wall power socket used by AC Regenerator (same line).
The Oscillation noise is now gone.
Still a very slight buz, but I think that is coming from the Tubes (6922 x 2).
Thanks again, I am very grateful for your advice.