Turntable Ground Wire Length - Does It Matter?

[Connor1a]

Hey Guys

Two questions for you...

I just purchased a couple sets of 3 foot Blue Jeans interconnects for my setup including my turntable. Their RCA pair don’t come with a ground option so I need to add one. I read in a comment on another site that the ground wire should be no longer than the length of the RCA interconnect. I’m scratching my head. The ground isn’t carrying current, but I’m not an electrician or engineer so what do I know?

Does the length of the ground wire matter?

And then I saw some debate here concerning the BJC cables. The discussion was around whether the low capacitance of the cables was or was not appropriate for the turntable to turntable preamp interconnect. I’m running a Fluance RT85 w/ a Ortofon 2M Blue cart and Schiit Mani 2 preamp. My chain looks like this:

Fluance RT85 —> Schiit Mani 2 —> WiiM Ultra —> NCx500 amp —> Warfedale Lintons

As stated above, I bought 3 foot BJC LC-2 cables for each of the RCA interconnects. Would you see any concerns with the capacitance of the cables in a setup like this?

Thanks much for you thinking!

 

[Balle Clorin]

Bjc has A phono cable that includes ground…
Your capacitance is fine, low is usually better anyway .your Mani is good flexible and happy with your cable, and your cartridge will be happy to,
No need to make av ground cable longer than interconnects, shorter cables is alway better, as long as it is practical

 

[DVDdoug]

I don't THINK the ground length is important but where it's grounded could make a difference.

The discussion was around whether the low capacitance of the cables was or was not appropriate for the turntable to turntable preamp interconnect

So "normally"... cable capacitance (which is in parallel with the signal) combines with output resistance to make a low-pass filter, potentially reducing high frequencies.*

BUT, a phono pick is inductive. That creates a resonant filter that usually resonates at a center-frequency slightly-above the audio range with its effects extending down into the higher audio range. That resonance creates a BOOST in the signal. Higher capacitance brings the resonance closer to the audio range and it tends to boost the high-audio frequencies so higher load capacitance has the OPPOSITE effect of what we "normally" expect!

Higher capacitance tends to BOOST the highs and lower capacitance tends to dull the highs. Zero capacitance is not optimum for a phono cartridge.


* With regular audio connections the resistance and capacitance are both low-enough that it doesn't affect audio frequencies and it's of no concern.

 

[Connor1a]

Bjc has A phono cable that includes ground…
Your capacitance is fine, low is usually better anyway .your Mani is good flexible and happy with your cable, and your cartridge will be happy to,
No need to make av ground cable longer than interconnects, shorter cables is alway better, as long as it is practical

I didn’t see one on Amazon, but went to BJC’s online store and found the one I think you’re referring to. It uses the same LC-2 RCA cable I ordered off Amazon. Thanks for the steer. But if I keep the RCA cables I ordered off Amazon, and buy a separate ground cable, is there anything wrong with my buying a longer ground cable? Unfortunately, the shortest I’m finding is 6 feet vs my interconnects which are 3 feet. Thanks much!

 

[Connor1a]

I don't THINK the ground length is important but where it's grounded could make a difference.

The ground would be connected between the Fluance TT and the Schiit TT preamp.

 

[Balle Clorin]

I didn’t see one on Amazon, but went to BJC’s online store and found the one I think you’re referring to. It uses the same LC-2 RCA cable I ordered off Amazon. Thanks for the steer. But if I keep the RCA cables I ordered off Amazon, and buy a separate ground cable, is there anything wrong with my buying a longer ground cable? Unfortunately, the shortest I’m finding is 6 feet vs my interconnects which are 3 feet. Thanks much!

Get it, and cut it in half it it creates a mess estheticslly , but almost any wire will do as ground wire, try whatever you have. Maybe wise to make it close to the RCA cables to avoid a possible big loop area

 

[MaxwellsEq]

I didn’t see one on Amazon, but went to BJC’s online store and found the one I think you’re referring to. It uses the same LC-2 RCA cable I ordered off Amazon. Thanks for the steer. But if I keep the RCA cables I ordered off Amazon, and buy a separate ground cable, is there anything wrong with my buying a longer ground cable? Unfortunately, the shortest I’m finding is 6 feet vs my interconnects which are 3 feet. Thanks much!

Any piece of wire will be fine. Don't buy anything expensive.

 

[cgallery]

Well just consider that the ground wire from your turntable connects to another really long ground wire that snakes through your walls and ends-up at your service (panel) and eventually connects to another wire that then travels out to a couple of ground rods that are driven into the earth.

Now ask yourself whether a couple of extra feet on the turntable side is going to make a difference.

 

[Connor1a]

Get it, and cut it in half it it creates a mess estheticslly , but almost any wire will do as ground wire, try whatever you have. Maybe wise to make it close to the RCA cables to avoid a possible big loop area

I went ahead and ordered the combined cable from BJC online. That way all three cables will come in one sheath etc. I’ll return the cables I purchased on Amazon. I realized that it’d probably drive my OCD nature nuts… Thanks much!

 

[Connor1a]

Well just consider that the ground wire from your turntable connects to another really long ground wire that snakes through your walls and ends-up at your service (panel) and eventually connects to another wire that then travels out to a couple of ground rods that are driven into the earth.

Now ask yourself whether a couple of extra feet on the turntable side is going to make a difference.

Peace! I was relaying part of a debate I read on an AVS forum elsewhere. I didn’t get it which is why I asked you guys. But as far as grounding goes, the ground wire only connects the TT with the Schiit preamp. The Schiit preamp doesn’t have an its ground lug connected to another grounded connection. Should it? Guess I never thought about (or rather I did, but didn’t do anything about it). I’d need another cable to do that… I could run one to my Panamax lug if necessary. What do you think? Thanks…

Edit - While on the topic, my WiiM Ultra is also running ungrounded. Should I run a ground to the Panamax lug as well? Funny how all these devices have ground lugs, but run on 2 prong power no?

 

[Speedskater]

The 'ground' wire should follow about the same path as the interconnects.

 

[Balle Clorin]

Well just consider that the ground wire from your turntable connects to another really long ground wire that snakes through your walls and ends-up at your service (panel) and eventually connects to another wire that then travels out to a couple of ground rods that are driven into the earth.

Now ask yourself whether a couple of extra feet on the turntable side is going to make a difference.

The house installation ground wire is a safety ground and has nothing to do with the TT ground wire , even if they may connect somewhere…..

 

[cgallery]

The house installation ground wire is a safety ground and has nothing to do with the TT ground wire , even if they may connect somewhere…..

Sure, but you missed my point.

 

[Balle Clorin]

….so why drag in wall wire if it is not your point…. We agree that the length of TT ground wire is of no concern

 

[cgallery]

To illustrate that the length of the turntable ground wire is of no concern. That, the turntable ground wire is typically connecting to a wire that is many (many!) times it's length, so an extra foot or three is of no consequence.

Others seem to have got this but you're struggling with it for some reason?

 

[Balle Clorin]

Life goes on ,, happy listening

The Rolling Stones - Melody (Remastered)

Listen to Melody (Remastered) on your streaming service

tidal.com

Since the problem is solved, here is another:
Are tube coolers good or bad? I tend to think it is best to let the tube radiate freely without obstruction that can radiate back ..
For an object at temperature T (Kelvin) and a surface area A, the net rate of radiated energy depends strongly on temperature:

Pnet = Prad - Pabs = σεA(T4 - Tenv4).

Can’t really measure any difference ,,yet

 

[Speedskater]

To illustrate that the length of the turntable ground wire is of no concern. That, the turntable ground wire is typically connecting to a wire that is many (many!) times it's length, so an extra foot or three is of no consequence.

There is.
You want the turntable chassis and a metal tone arm at about the same potential as the cartridge to pre-amp cable's shield.
So the 'ground' wire should follow the signal cable's path, to reduce the 'ground loop's' area & resistance.

 

[Chester]

Funny, I was wondering this very same thing myself recently OP. Reading these posts, some say it does matter, some say it does not.

I have 1ft RCAs and the ground is probably about 5ft…..should I be worried?

 

[mhardy6647]

Life goes on ,, happy listening

The Rolling Stones - Melody (Remastered)

Listen to Melody (Remastered) on your streaming service

tidal.com

Since the problem is solved, here is another:
Are tube coolers good or bad? I tend to think it is best to let the tube radiate freely without obstruction that can radiate back ..
For an object at temperature T (Kelvin) and a surface area A, the net rate of radiated energy depends strongly on temperature:

Pnet = Prad - Pabs = σεA(T4 - Tenv4).
View attachment 412593

View attachment 412594
Can’t really measure any difference ,,yet

Virtually all vacuum tubes made for consumer use are meant to be passively cooled and shouldn't even need forced air cooling unless the design/layout/installation of a particular electronic component markedly inhibits convective cooling/heat dissipation.

Audio power tubes (and HV rectifiers, as well as other power tubes) are meant to run quite hot (far too hot to touch). Tube handbooks always state that adequate ventilation should be provided.

Most consumer electronics small signal tubes operated properly (i.e., at reasonable operating points) seldom get more than warm to the touch.

The sleeves above might add some value for reduction of microphonics, but otherwise should be unnecessary in a well-designed component.

Funny, I was wondering this very same thing myself recently OP. Reading these posts, some say it does matter, some say it does not.

I have 1ft RCAs and the ground is probably about 5ft…..should I be worried?

no, other than whether you might perhaps be manifesting symptoms of incipient neurosis.

 

[cgallery]

There is.
You want the turntable chassis and a metal tone arm at about the same potential as the cartridge to pre-amp cable's shield.
So the 'ground' wire should follow the signal cable's path, to reduce the 'ground loop's' area & resistance.

What ground loop? There should be no ground loop.