Problem with phono stage

Hmm - I looked up the manual for the Black Cube and got the gain settings from there - perhaps I saw an older or newer version. This manual talks about not only the dip switches, but also a gain jumper that adds 10db.

In any event, I also have an FMJ A28, and while its phono stage is quite good, and very quiet, my other external phono stages into the aux inputs (A Sutherland PD3D and a Music Hall PA2.2) either sound better (PH3D) or roughly equal the internal phone stage. You should get great sound with the Black Cube and this amp. I am using a Shure V15III and a Grado Gold 3 on my tables at the moment. 

The A28 has a numeric volume read out, which the manual claims is in decibels when in the reference mode. I believe the internal stage is roughly 40+db of gain - so I would think the Black Cube into the Aux input and the internal phono stage should be equal in terms of loudness at the same volume setting on the A28. If they are roughly equal, and you still hear a lot more noise with the cube, then I don't think the problem is cables or the cartridge or the amp.

Ejb14 is correct. There are several other settings that the Black Cube has, but must be done from internally on the board. To include, as mentioned, a gain jumper. However, it is not really a “jumper” that is easy to swap, at least not on mine (I have the SE) it requires some surgery.

emilm, Yes, atmasphere is talking turntable to phono input. You also want to keep the cables as short as you can. 

Dear @emilm : Do it you a favor and forgeret about that IC cable capacitabnce for the moment.

First than all the Lehmann must be perfectly set up for the Nagaoka 5mv. MP-110 cartridge. Your phono stage comes with several alternatives for set up and for what I read in this thread you still are not an " expert " about.

So my advise is the same as other gentleman in this thread: put in direct contact with Lehmann explain it your system issues with that cartridge and follow his instructions. With out the rigth Lehmann set up with that cartridge all other advises here are useless and futile.

Don't waist your time or money in cables till you make the Lehmann advises. Only my opinion.

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

I thought capacitance for cables didn't matter with a MM Cartridge , only MC.

@vinylvin ,  @emilin
Actually it matters quite a lot!


With a high output MM cartridge the inductance tends to be rather high. This in tandem with the capacitance of the tone arm interconnect cable connecting into the phono preamp results in a resonant peak. If the cable capacitance is high (as is often the case with many regular audio cables) the peak will be forced down in frequency, and can easily be somewhere at the top of the audio band.

This will make the system brighter and more susceptible to ticks and pops which tend to have a high frequency nature.


The suggestions about checking loading and overall gain were good ones. But we now know that the gain is 41dB which is fine. With regards to loading though, the cable capacitance plays right into that. Take a look at this page:http://www.hagtech.com/loading.html
Play with the numbers in the calculator, including the default. The link I provided earlier for the tonearm/phono cable from Blue Jeans has about 12pf/foot; you can see by dropping in 36pf for a 3 foot run that the resonance is pushed up higher, outside of the audio band. So that is where you start; after that you work on whatever loading is needed.


It is also a good idea to contact Lehmann: I think you will find that they confirm everything I've said on this thread so far.