System Sum - at a loss...

[TLS Guy]

I should note that the plug lead itself is detachable - I could just replace it with a three pin type detailed above if that's a likely solution?

That is a solution, however we don't know that the plug on it is wired correctly.

The correct solution is to have someone open up the sub. Then you need a 3 pin MK plug swaged to a 2 conductor wire. The plug should have the plastic "grounding" plug. This lead should replace the existing power cord. Whoever does this must know which is the live and which is the neutral connection inside the sub. SVS will have to tell you this.

Alternatively you need to find out which wire is live and which is neutral coming out of the sub now and then wire an MK plug correctly.

The fool proof and safest solution is the first option.

Currently the whole set up is improper and probably very dangerous.

You really should not be using this sub until correct live and neutral termination is certified as correct by someone who understands these problems.

 

[barryb5]

Thanks once again, TLS Guy. If I follow correctly, ideally SVS should have supplied one like so...

https://www.amazon.co.uk/Power-Mains-Kettle-Cable-Lead/dp/B0058GXEZ4

Note the adaptor lead and plug both take and use three prongs.

To be honest, when I first queried with the SVS EU supplier prior to purchase they said it came with a UK style plug, 240v etc. And then it arrived without! Maybe I should seek an exchange at this point, if they do indeed have this version of the sub.

 

[TLS Guy]

Thanks once again, TLS Guy. If I follow correctly, ideally SVS should have supplied one like so...

https://www.amazon.co.uk/Power-Mains-Kettle-Cable-Lead/dp/B0058GXEZ4

Note the adaptor lead and plug both take and use three prongs.

To be honest, when I first queried with the SVS EU supplier prior to purchase they said it came with a UK style plug, 240v etc. And then it arrived without! Maybe I should seek an exchange at this point, if they do indeed have this version of the sub.

No it should have a plug like this, that I showed you before.

If you look at it you will see only the live and neutral are conducting, the ground is not.

Now let me ask you this, is the AC cable hard wired to the sub or is there an IEC connector on the sub into which the power cord plugs?

If there is an IEC connector or other internationally recognized connection, then your solution is simple. You would just purchase a power cord with the plug I showed you and the correct connector for your sub on the other end, and you are home free.

The plug you showed has an IEC connector on the opposite end to the MK plug. You just need the two pin polarized version to avoid a ground loop.

We seem to have an increasing number of members outside North America. The location of members should be required as part of the registration and prominently shown. Not to do so invites inadvertent erroneous and dangerous advice.

 

[barryb5]

There is indeed an IEC connector - it has two prongs, apologies, I did try convey this info before, perhaps without sufficient clarity. I'll purchase one and update with results, likely tomorrow. Thanks again.

 

[TLS Guy]

Does the sub hum without turntable connected and phono selected?
There's a huge thread on AVS dealing with debut hum.
Cheers, Mac

https://www.google.com/search?q=pro+ject+debut+carbon+hum&ie=UTF-8&oe=UTF-8&hl=en-us&client=safari

Thanks for that post. I was unaware if the problem with the Project Carbon turntable. It is not really a hum problem, but a rumble problem.

Anyhow it is a disgrace to send out turntables in that condition. Yes, it is a total disgrace! That turntable is now off my recommended list and I will not recommend any of their products again.

 

[TLS Guy]

There is indeed an IEC connector - it has two prongs, apologies, I did try convey this info before, perhaps without sufficient clarity. I'll purchase one and update with results, likely tomorrow. Thanks again.

Well I hope you are set. That will eliminate the possibility of current leakage from the wrong AC polarity.

I see from that thread on AVS, that those Project Carbon turntables are sent out improperly manufactured. I was unaware of this and its a disgrace. So make sure the belt is not rubbing on the pulley rims and is properly centered on the pulley. It could be that the sub reproduces the low frequency rumble the main speakers can't.

 

[barryb5]

Well, unfortunately the plug as recommended did not do the job - hum still present. Worth a shot. However, a potential solution emerged in that if the cable running between sub and amp is disconnected the hum disappears from the TT, meaning I could in theory use the wireless option, I think... Ideally, I would prefer it cabled, but as in life, compromises sometimes are to be made.

 

[barryb5]

I should also note that I tried different cables between sub and amp with no change.

 

[Swerd]

@barryb5

I do sympathize with your problem, and I can offer no solution. If TLS Guy has tried, I can't suggest anything better. I offer this cartoon in the spirit that, when all else fails, taking time out to laugh never hurts.

 

[TLS Guy]

I should also note that I tried different cables between sub and amp with no change.

Do you have the project carbon with the AC synchronous motor, or the DC motor. If AC is does the turntable have a three pin plug or two?

What units are connected in you system that have grounded plugs?

You can occasionally get ground loops from two pin double insulated units, because ground and neutral are connected at the panel.

Ideally all systems should have only one ground, which should ideally be the preamp.

 

[barryb5]

My feeling is that my TT is the AC version with a three prong plug. I think the DC has a detachable power supply which mine does not, however I will have to confirm that it is indeed the AC by finding manual (wherever it is!). As I'm in Ireland, everything is grounded plugs - the TT, amp, sub, chromecast.

@Swerd, appreciate the cartoon, that gave a laugh!

 

[TLS Guy]

My feeling is that my TT is the AC version with a three prong plug. I think the DC has a detachable power supply which mine does not, however I will have to confirm that it is indeed the AC by finding manual (wherever it is!). As I'm in Ireland, everything is grounded plugs - the TT, amp, sub, chromecast.

@Swerd, appreciate the cartoon, that gave a laugh!

You have the AC synchronous moor version. If you had the DC motor you would not have this problem.

This is an unusual neutral lead ground loop.

What I would do next is to get a heavy gauge copper wire, at least 10 gauge and put a spade or loop connector on both ends. Find a screw on the chassis of you sub amp and fix one end there, now put a connector on the other end and connect it to the turntable grounding screw on your amp as well as the turntable ground.

 

[Latent]

Here is an example of a wireless sub audio transmitter that you can use as a last resort.

http://www.amazon.com/Dayton-Audio-WS-12-Transmitter-Subwoofers/dp/B00A4V22G0/ref=sr_1_1?s=electronics&ie=UTF8&qid=1463006434&sr=1-1&keywords=SUB+wireless+audio+transmitter

Hopefully you can find a better solution though!

 

[barryb5]

You have the AC synchronous moor version. If you had the DC motor you would not have this problem.

This is an unusual neutral lead ground loop.

What I would do next is to get a heavy gauge copper wire, at least 10 gauge and put a spade or loop connector on both ends. Find a screw on the chassis of you sub amp and fix one end there, now put a connector on the other end and connect it to the turntable grounding screw on your amp as well as the turntable ground.

Thanks TLS Guy, I will look to do the above suggestion over the course of the weekend. Will post results as soon as I can. Fingers crossed.

@Latent, thanks, have been browsing such products but will look to exhaust the wired avenues provided here first. Ideally wired is my preference given its in-expense and fidelity, less plugs etc.

 

[barryb5]

@TLS Guy ...I tip my cap to you, good sir - your suggestion noted above (copper wire) has rid my system entirely of hum! A weekend of buzz free listening is now planned! Super appreciative of your repeated input, and of others who contributed too. I'll toast you all soon this eve, sláinte!