Phono cable not caps to le with preamp?

bicycle, "knowledge is never useless"????

It's true; I have too many posts here. But I think that is over a 15-20 year period and includes the duration of the pandemic when I was going out of my mind with boredom and the confinement.

On the other hand, can you name your phono stage? And by the way, you don't necessarily HAVE TO ground your turntable.  It's something to try if you have hum. I've got 5 turntables up and running, and none of them is separately grounded to the phono stage(s).  Yet I have no issues with hum.

He never mentioned what kind of phono amp he had, knowledge is never useless,

The last suggestion to call the manufacturer customer service is probably his best bet at this stage (pun intended)I see you’ve got 12.5 thousand posts. How do you have time to ever listen to music.

The original poster wasn’t even aware he had to ground his turntable so I’m giving him as much information as possible,

Just noticed the ops post is from January so he’s probably taken care of it by now. Carry on my wayward son 

Bicycle, am I correct in the belief that the blurb you quoted is from your owners manual and that your phono stage is not identical to the OP’s? If so, the bit about playing with internal ground switches is useless to the OP, because the vast majority of phono stages provide no such options. However the verbal points to consider do apply to most situations. I think his new phono most likely has an internal short owing to a cold solder joint or to a broken one.

My phono pre gives these instruction and has these grounding switches as part of its circuit.

Improper grounding of an outboard phono sections can often result in excessive hum. Since the grounding on every sytem is different, it is impossible to provide a uniform grounding strategy that will work for every system. Be assured that with correct grounding almost all audible hum can be eliminated. If you are experiencing some hum, try the following:

1. Be sure to have the phono pre plugged into the same outlet or power strip as your preamplifier.

2. Connect the turntable ground to the ground lug on the rear of the Phon Pre

3. You may need to connect a ground wire from the Phono pre to your preamplifier.

4. Try different combinations of the internal grounding switches g1-g4 under the Phono Pre access panel
    

   

   Grounding switches g1 through g4:

   The four small grounding switches g1, g2, g3, g4 will most often be set in the forward position as shown in the preceding photographs. If you are experiencing excessive hum you can try moving them in the various possible configurations g1, g3 forward g2, g4 to the rear, etc.. Some cartridges that share internal grounding between channels may require that one channel be grounded while the other is not (e.g. g1, g2 forward and g3, g4 to the rear).

   

Some or all of the above should eliminate most hum. If this fails to cure the hum, call customer service for further advice.
If not GoChurchGo trying Thoughts & Prayers may work

Sounds like maybe a defective phonostage. 🙁

@ghdprentice ​​@lewm

got home and swapped cords again. I get sound from both outputs. Playing with the ground alters the tone of the buzz a little bit that’s it.

old phono preamp back in and quiet as a tomb.

seems like sloppiness here but I know nothing about soldering (see my system pics for the guts of the new phono)

EDIT: funny enough I just realized the ground from the TT was never connected to the Andover. And yet it’s still dead black quiet. 

@lewm it’s a buzz. Like overdriven guitar sort of. I put the old phono back in (Andover SpinStage) and it’s dead silent again.

ill play with it tonight and see what I can glean from it. I’m in touch with the importer as well.

edit: forgot to mention the phono stage is plugged into an isolation transformer.

A VERY loud hum is possibly due to a more major ground fault than the hum that typically results from failure to ground the TT or tonearm, in my experience. If the usual suspects don't work at all, I would look at either the cables (maybe the solder joint between the cable itself and the grounded barrel on one of the RCA connectors came loose) or the new phono stage itself.  Crack open the chassis and have a look at the solder joints to the outputs.  But one huge question: Is the hum in both channels or in one channel?  If in both channels, then my hypothesis loses some credibility.

I just had a thought. Since the phono and power supply are in wood boxes instead of metal would they’ve more susceptible to interference?

@ghdprentice  I have done this yes. I also tried various different cables and plugged into different outlets. I also moved the power supply as far away as the umbilical allows and moved the unit itself away from everything else.

my cables are shielded and have never had this issue.

if I unplug the input RCA’s it’s dead silent. If I plug them in it’s an overdriven buzzing sound that is affected by the volume on the line stage. 

Yes, ground. Need to run a ground from the turntable to the phonostage. Long ago I had a turntable without a grounding wire. I found a nut connected to the chassis on the bottom of the turntable and ran to the ground connector on the phono stage. I never heard it again.

Definitely.

Ground issue?