Simaudio MOON 610LP with Lyra Kleos

Is it humming or hissing? Because these are completely unrelated. And just a heads up, you will not be able to get rid of the hissing noise.

It’s more humming than hissing. And while we are st it, what’s the difference in the source and why it won’t go away?

60Hz hum is usually improper grounding or due to a ground loop. Not easy to solve. Make sure that the cartridge leads are snug. Tonearm has ground continuity all the way to the ground post. You may even try disconnecting the ground cable entirely as a test. 

There may be another component in the system that is causing a ground loop. Cable box is a very common culprit. Light dimmers. And just about everything else.

Hissing is input noise from the OP amplifier. In your case I believe it's a National part, LM4562. It's very low noise, but some hiss will be audible if the preamplifier's volume is turned up and no record is playing. There are quieter designs using discrete jfet inputs. 

When did this problem become evident? How long have you had these components? Is the SIM’s MC gain, compatible with the LYRA?

I can assume that if your using a Kleos, in order to maximize that investment, you'd need another phonostage.

It's a highly configurable $7500 phono stage so it should be capable of  working with the Kleos.

But how long the OP has had these, especially the phono stage, is a valid question as we can the deal with some possible setup issues.

Is this your first time using and setting up the Sim Alex?

Good mornig, WOW, a lot of replies came overnight :)
Thank you all for your suggestions! 
Just to clarify couple of things: I use Clearaudio Performance DC table with Satisfy Karbon arm (has tonearm cables hard-wired, including the ground wire). Table, arm and Kleos have been used before in a different setup and were quiet. I've also used 610LP in another setup for a few months and it was completely quiet - no hiss, no humm. 610LP is very flexible and is definately compatible with Lyra.
There are no cable boxes, light dimmers, etc anywhere near the setup. 
There is a passive speakers switch box, Luxman AS-55 but once again, it was used in a different setup before with no humming effect.
Speakers are set 12 feet away from the table. 
I've tried to use different cables, different inputs on my integrated amp, connecting and discommecting ground wires from the bearings and/or the arm, turning off (disconnecting mains) all other components in the system except table, phono preamp and integrated - all with no success.
Anything else I should try? But please, anything short of replacing 610LP or the cartridge :) 

Thanks again!
Alex

Can't think of too much. I'm assuming you are using the single ended inputs and outputs on the 610 and that the balanced jumpers are inserted?

Apart from that I would be setting the gain initially at least at the 56 dB setting as the Kleos appears to have a relatively high output of around .5 mV.

It also has relatively low internal impedance around 5.5 ohms so I would initially experiment with the loading in the 75-150 range. But Lyra has a very wide range spec'd for loading (supposedly based on the capacitance of your phono cable) so you may end up experimenting with much higher ranges than that.

What what do you think about using a step-up transformer? Bobs Devices have couple of models all with a ground post and use the Moon in MM mode?

So..a new issue? Can you be more specific as to when you first noticed this issue?

It is a new issue. But each one of these components have been used in other combinations, including cables. 

Just an idea, I had a hum problem with my center channel and mono amp for driving it. I inserted a Jensen Iso-Max isolation transformer in the interconnect, and 90% of the noise went away. It might be something to try. I have a two-channel analog set up (using the same main speakers, separate tube preamp and SET 300B amp) with no noise issues.

Hope you get it sorted out.
Regards,

Dan

With a step up transformer, you will take a significant hit in sound quality.

I suggest that you check Bob's devices web site for his article on grounding problems and how to solve them. It is the best piece I have seen on the subject. You probably don't need a step up transformer with a .5mv cartridge but I can tell you from experience with many cartridges that a good step up transformer helps
the sound stage significantly on low input MC cartridges. 

Finally, I would bet that you have a ground loop hum somewhere in the system. Make certain that all of your phono cables are far away form electrical components with transformers. 

Thank you 

Dear @alexkrich: Your 610 is a very good unit and it performs better if you use it balanced because is the way was designed ( fully diferential. ). I agree with @hdm that you need nothing with, obviously not a SUT that only can degrades the quality level performance in the cartridge signal due the great 610 design and excecution design.

First than all balanced way is the way to use the 610, nothing on it can compares connected in non-balanced way.


""" I have the arm and bearings grounded ... """

what do you mean with that?. Which bearings are you talking about? because if tonearm is grounded then that’s all you need ( tonearm bearings are part of the tonearm. ) and additional you have to have grounded the TT.

I never had any issues with my Kleos and other Lyra cartridges as the one you have.

As @browndt said take care that the IC tonearm cable always stays away from electrical lines or transformers and if the IC has to stays near electrical lines/power amp cables then the IC tonearm cables must cross over those lectrical lines at 90°.

Could be too that somewhere the ground wire was disconnected/unsoldered, so you have to check to be sure all the ground wires are soldered to its terminals.

I repeat, with your 610 avoid to use any SUT.

regards and enjoy the MUSIC NOT DISTORTIONS,
R.