PV-5 hum on phono ouput only
PV-5 hum on phono ouput only
I have the same hum on both channels of the phono output on my PV-5. It does not occur on other outputs. It does not change when I plug the unit into different outlets. It is the same whether my turntable is on or off. Is this a tube or ground problem, or something else? The tubes are old but I have hardly used the unit in years. If it is a ground problem, what should I ground the unit to? I attached a wire to the ground and it doesn't seem to affect the hum when I touch various things.
Re: PV-5 hum on phono ouput only
Hi ecoman, welcome to CJO.
Few questions. Did this just start happening or is it new? If it's always been like it then it may be a simply mismatch of cartridge to phono stage gain. Have you tried another turntable/cartridge to see if' it's the same?
If you think it's ground loop problem, you can buy a RCA to RCA ground loop isolater for under $20. I highly recommend having one as it really does help narrow down ground loop issues. Ground loops are often really difficult to narrow down and eliminate, a ground loop isolator will at least tell you whether that is the problem or not.
Of course the tubes in the phono stage may be at fault. You can try switching the tubes with each other to see if the sound is changed if you don't have another set to switch out all of them.
If all these are negative then you may have a component failure.
Few questions. Did this just start happening or is it new? If it's always been like it then it may be a simply mismatch of cartridge to phono stage gain. Have you tried another turntable/cartridge to see if' it's the same?
If you think it's ground loop problem, you can buy a RCA to RCA ground loop isolater for under $20. I highly recommend having one as it really does help narrow down ground loop issues. Ground loops are often really difficult to narrow down and eliminate, a ground loop isolator will at least tell you whether that is the problem or not.
Of course the tubes in the phono stage may be at fault. You can try switching the tubes with each other to see if the sound is changed if you don't have another set to switch out all of them.
If all these are negative then you may have a component failure.
-admin
Home Theater in Member Gallery
Main stereo: ART Amplifier and ET7s2. 2nd stereo: PV-14L and MV-55. Previously Owned: PF2 preamp, Evolution 2000 Amp, PV-12AL preamp, D/A-2b Vacuum-Tube Digital Processor.
Home Theater in Member Gallery
Main stereo: ART Amplifier and ET7s2. 2nd stereo: PV-14L and MV-55. Previously Owned: PF2 preamp, Evolution 2000 Amp, PV-12AL preamp, D/A-2b Vacuum-Tube Digital Processor.
Re: PV-5 hum on phono ouput only
I have a PV5, try The following:
1. Grounding the turntable to the preamp.
2. If that doesn't work disconnect the turntable.
M~
1. Grounding the turntable to the preamp.
2. If that doesn't work disconnect the turntable.
M~
Re: PV-5 hum on phono ouput only
Thanks for the advice. Tried grounding TT to PV5 and that didn't help. Disconnecting TT removes hum, but that is the only thing I am using the PV5 for. Will try the isolated next.
Re: PV-5 hum on phono ouput only
Okay
Then the problem appears to be connected somehow to the turntable/phone cartridge. Try the following:
1.Disconnect the phonoleads from the back of the cartridge
2. reconnect the turntable
3. Check for hum.
If there is hum reconnect the cartridge one side at a time (yeah I know) and check for hum.
If there is hum try another cartridge.
M~
Then the problem appears to be connected somehow to the turntable/phone cartridge. Try the following:
1.Disconnect the phonoleads from the back of the cartridge
2. reconnect the turntable
3. Check for hum.
If there is hum reconnect the cartridge one side at a time (yeah I know) and check for hum.
If there is hum try another cartridge.
M~
Re: PV-5 hum on phono ouput only
Disconnect in the leads worked and the hum is gone. Thank you.