Is ground noise really normal? If so, why?

Well, it took a while (and longer for me to respond), but I figured out that it was my Ayre phono preamp. They repaired it and now it's 100%. And paired with a Viella V12! 

Ground noise is absolutely NOT normal.  I have many receivers and preamps and none of them exhibits ground noise.

Your phono section should be silent between tracks.  With no record playing and your gain turned up it should again be silent.  It’s like that on my Sansui 9090db, marantz 24, 1030 and 7, and completely black on my Phase Linear 4000 series one preamp.

Check your cartridge wiring (some tone arms differ in wiring configuration i.e. SME vs Grace).  Make sure the arm is properly grounded as should be the motor unit of the turntable itself..

Ground noise or hum would drive me nuts.  You may even have a bad cartridge lead.  

N.

Intermediatic, Tonearms (and the vast majority of cartridges) are indiscriminate.  You will have four wires from the headshell plug going either to a DIN plug out or some similar output plug.  If there is a DIN plug or some other similar type of termination at the back of the tonearm, all you need is a true balanced phono cable complete with XLR connectors, and you can then plug that into your Ayre.  There should be a DIN connector (or similar, but typically a DIN) at the tonearm end of the balanced cable.  The maker of the cable will have wired up that DIN plug to carry the signal in balanced mode to the XLRs.  Everything else is the same, NO re-wiring of your tonearm is needed. Get an inexpensive Audioquest or Anti-cable balanced phono cable (specify "balanced") with XLRs at one end and a female DIN plug at the other, and Bob's your uncle. (I specify those two companies only because they give good bang for buck and they can be relied upon not to sell you a single-ended cable that merely has XLR terminations.)

Alas, my tone arm is not balanced as I didn’t know it was an option. So while the P5XE feeds the rest of my stack in balanced mode, the tonearm wiring is good old hummy. I’ve to a spool of low voltage wire on the way (remember how great it was to have old radio shack around for that sort of thing?), maybe I can get rid of the noise by grounding the chassis in a few more spots,

My system is dead quiet..even on phono...I have an all Ayre system with Vandersteen 5A's

As others have alluded to the OP should clarify what he means by "ground noise." Hum? Hiss? Something else? Is it present only when the stylus is in the groove of a rotating record, or is it also present when the stylus is lifted off of the record? Or is it present even when the platter is not rotating and the turntable is turned off?

Also, what cartridge is being used, and what gain and input impedance is the phono stage set to? For example, if the cartridge is a moving magnet type and the input impedance is set to 100 or 1000 ohms (the two choices that are provided in addition to the 47K setting that should be used for moving magnet cartridges) it would certainly result in poor signal-to-noise ratio.

But to provide a preliminary answer to the initial question, I would not expect an Ayre phono stage to have objectionable noise levels unless there is something is wrong in the setup or the unit is defective.

Regards,
-- Al

Ralph, First we need to determine if the OP is truly experiencing noise due to bad grounding.  I'm not sure.  But in balanced mode, I've never had any audible grounding issue, no matter how sloppy I might be with grounding the tonearm or turntable or etc.

'Ground noise' sounds like a bad ground connection to me.
If you have a balanced preamp then the ground of the arm should also be the shields of the tone arm interconnect cable and tying to pin 1 of the XLR connections on your preamp. The '+' and '-' outputs of the cartridge then connection to pins 2 and 3 of the XLR input connectors.

If you truly own an Ayre P5Xe, you are missing out.  You have a true balanced phono stage, and you should be connecting your cartridge to the input in balanced mode.  To do that optimally, you want a true balanced phono cable, which is a cable that uses identical conductors for each half of the balanced signal; one conductor being connected to each "end" of the cartridge output.  Cartridges are inherently balanced devices (at least 98% of them).  The pin on your cartridge that is labeled "GD" (for ground) can actually be used to derive the negative phase of a balanced signal.  The pin labeled "hot" or "R" or "L" will then put out only the positive phase of a balanced signal.

So, basically, to convert to balanced mode all you need is a balanced phono cable with XLR termination.  You would connect the XLR to the XLR input on your Ayre phono.  This will eliminate any noise due to poor grounding, totally.  As others have correctly noted, this will not eliminate groove noise, etc, etc.  But you could say good-bye to 60Hz or 120Hz hum due to poor grounding. If that is the real source of your problem.

Now, if you tell me that your cartridge is already connected to your Ayre in true balanced mode, then I would say you do not have noise due to poor grounding.

Further to what @pragmasi said, ensure there are no routers, cable modems, or Wi-Fi units nearby. Move them with the volume up and note the change in hum levels.

I'd start by checking your interconnects are making good contact with the connectors on the TT and preamp (swap them out if you have spares), also check that the TT ground connector is securely connected to the preamp.
If the hum is still there then search up 'Ground Loops', it may be worth experimenting with ganging up all the mains plugs to a single wall socket if you haven't done that already.
Other than that I'd try to locate the source of the hum by disconnecting equipment until the hum goes away. Also check to see whether you have any equipment nearby that may be emitting interference.
The TT and preamp you reference look pretty high quality and I would not expect to hear any hum at all. The link provided by @hagtech looks like a good starting point.

Vinyl roar? Or hum?

Sadly, hum is quite often the norm. It does not have to be! A properly set up system can be dead quiet, where all you hear is groove noise between songs.

Hum is a system-level issue, not due to any single component (unless it’s a crappy  design). Here is some more info:

http://www.hagtech.com/pdf/eliminatingnoise.pdf

Well white noise is a thing. Like pink noise only with more treble. Dead silent is a thing, its the complete absence of noise. Near is a thing. It means close but not quite there. So yeah I would say near dead silent white noise is a thing.

millercarbon,
"near dead silent white noise"...is that a thing?

A certain amount of noise is indeed completely normal. What is a completely normal amount of noise for vinyl is also a lot more than the near dead silent white noise you and your kids are used to from digital. (That the digital signal is itself noise is a whole other story.) Exactly what amount of noise is completely normal however is hard to convey sight unseen in a forum post.

What I do know for sure however, there is no ground noise. There is groove noise. Surface noise. Ground loop hum. Radio frequency noise of all kinds and levels. Seismic vibrations of all kinds. Ground itself however is where spare electrons go to die. Ground is ground. To have good ground is almost by definition to have no noise. Ground itself is the opposite of noise. It is the anti-noise.

So what are you talking about? Hum? How much? Sounds like its only audible in the silence between tracks??