Problem with phono stage


Hello Fellow Audiogoners,

I need help with my Phono stage. It is Lehman Audio Black Cube from Germany.  It was recommended from Simao, a very respected Audiogon member who helped me a lot when I was building my stereo. It costs 450$ brand new which I bought used from this site. Michael Fremer considers it one of the best steals in phono stages. I get a little bit better detail and bass extension BUT it also much noisier. I can hear the pops and any other noises  on the records much more then with the phono stage of my Arcam FMJ 28 which turned out to be a surprisingly good one considering it is an integrated one.
I also switched the cables but the noise is still there.
Is this a common problem with added phono stages as opposed to integrated ones or something is wrong with my phono and needs to be checked.

All help will be greatly appreciated.
Emil


emilm
Dear @emilm and friends : first than all Nagaoka is not MM design but IM similar to MI and the like where normally internal inductance is not really high ( say over 600. ) so with that 150/200 capacitance in the Lehmann and due that has a high overload design seems to me that that is not the problem but Lehmann overall set up.

It's obvious that if you change your cable for a better one or just different the sound you will experience with will be different but before you take that choice contact Lehmann and if after that you want to invest in your analog rig then could be better to go with the MP-300 from Nagaoka.

With MM cartridges always is better to have a low capacitance cable but almost any today decent cable are low capacitamnce designs in the other side there are MM cartridges as the AT25 that comes with low inductance, in this model only 85 more in the MI/IM territory.

Today phono stages are not like in the past an almost all comes with really good overload margin.

Don't worry about clicks and pops because there are more critical issues for the cartridges shows it at the best.

Look, this is what any one can read in the latest Original Master Recording LPs from MoFi ( Mobile Fidelity Sound Labs. ):

"" DUE TO THIS PROCESS,THERE MAY BE OCASSIONAL POPS OR TICKS INHERENT IN INITIAL PLAYBACK.........."""""

Regards and enjoy the MUSIC NOT DISTORTIONS,
R.

Btw, problems with capacitance normally will be at a frequency range that even stays says at 17-18khz can't we perceived and again today phono stages comes with pretty decent designs.
where normally internal inductance is not really high ( say over 600. ) so with that 150/200 capacitance in the Lehmann and due that has a high overload design seems to me that that is not the problem but Lehmann overall set up.
Let's drop these values into the calculator and see what pops up shall we? Giving Raul the benefit of the doubt we'll use 500mH for the cartridge inductance, but the Lehmann has a 100pf input capacitance; if we assume another 40pf for the Audioquest cable mentioned above:http://www.hagtech.com/loading.html

-we got a peak at 19KHz. BTW that's a 10dB peak; its going to be audible. The slope of the peak is there at 15KHz and there will be phase shift elements easily down to 10KHz, which will be perceived as brightness. Clearly keeping the cable capacitance down is paramount.

Don't worry about clicks and pops because there are more critical issues for the cartridges shows it at the best.
Increased audibility of ticks and pops is a clear sign of a problem. If the obvious problems of setup are overcome (VTA, HTA, tracking pressure and so on) and the ticks and pops are worse, then with any high output cartridge (which will have a higher inductance in order to produce that high output) the loading needs to be addressed. To that end, you start by minimizing the capacitive load on the cartridge, as the more capacitance the lower the electrical resonant peak (hence a low capacitance cable). After that then you look into reducing the load resistance. For example with many Grado high output cartridges, a load in the neighborhood of 10K takes out the brightness that you might otherwise hear with the stock 47K load of the phono preamp input.


But all cartridges are electrical generators, meaning that the lower the resistance of the load, the more work the cartridge has to do to make its voltage.

This causes the cartridge cantilever to become harder to move. For this reason alone, its worth it to start by having the capacitive load minimized first!
Btw, problems with capacitance normally will be at a frequency range that even stays says at 17-18khz can't we perceived and again today phono stages comes with pretty decent designs.

Its easy to see that this statement is false.

Speaking of capacitance, phono cable single ended and balanced, will capacitance of the cable affect the same on either case?


Weird/curious that you choosed in Nagaoka IM design 500 and not 300mH. Why did you do that?

300mh is way nearest to the real Nagaoka value than 500mh and with 300mh the resonace frequency is at 24.6khz Way different and as we can see through the Lehmann specs it is designed with very high overload levels.
So, that’s not the trouble.

What if you take the MM AT25 85mh along say those 600pf? even with that extremely high capacitance the resonance is over 22khz. At normal 200pf the resonance is 38.6khz ( fundamental frequency. harmonics that goes inmmediatly to 77.2khz. )


"" its going to be audible. The slope of the peak is there at 15KHz and there will be phase shift elements easily down to 10KHz, which will be perceived as brightness. ""

A surface LP click certainly is audible as a " click " sound not as brigthness and I’m talking of clicks and pops because that’s what reports the OP not brigthness: he said: pops and other noises and never mentioned brigthness.

So what’s all about? and of course that you can’t perceive as a click or defined kind of sound 17khz-18khz ( you can’t aisle it. ), you just can’t do it.

In the other side the harmonics of that resonance at 19khz ( the fundamental. ) goes to 38khz almost at once. My information is not false.

Why is false? proved it is false not only post it. You are the one whom say is faklse then: proved not talk, we need facts. I know as usual with you: you have no facts at all. Pity.

A gentleman with deep knowledge levels way higher than you and ovbiously than me says about:

" Clicks don’t inherently have a frequency because there is no repetition in the signal. That would be like asking "what is the frequency of an impulse? ""

The Hagerman calculator gives an " idea " of what could happens but exist other parameters around it that certainly changes the calculator values. Exist a very complex relationship between several electrical and mechanical parameters to try to aisle one of them.

Your " terrorism " has no limits because you want and like the " protagonism " but unfortunatelly you have not the rigth knowledge levels and skills to has it. Sorry for that. Try again.

R.

Btw, a few days ago you posted:

""" With regards to surface noise I agree most of that is in the groove..................................................
The surface noise is mostly an artifact of the pressing plant ""




Dear friends: Some very well know MM/MI/IM cartridge inductance values:

Stanton Series 100: 270mH
AKG P25MD :  170mH
P100LE ( fabolous/unique.): 90mH
Technics EPC100CMK4:  33mH
Audio Technica ATML-180: 210mH
Audio Technica ATML-170: 380mh
Sonus Gold: 150mH
Shure Ultra500: 330mH
Shure V15 typeV: 330mH
Pickering XSV5000: 290mH
Astatic MF-200: 90mH
ADC 26/27 : 150mH
Signet TK10 MLMK2: 180mH


@atmasphere  : No one approach 500mH. In the other side all those cartridges and any MM/MI/IM can be loaded at 20k, 47k, 100k or 150k , I intented all these values and stay with 100k. I know of audiophiles that loaded their cartridges at 15k with good results too. The Hagerman calculator use only 47k that's one of multiple options about.

As I said, you don't have the rigth knowledge levels, you need as urgent learn about. Do it and come back, till then: bye bye / chao ! ! 

R.