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Ricardo this is for you.
Here you see a bespoke 6000,-€ phono stage that i played to professional with comments like "Magical".
The left channel is fine at low volume and the right channel is OK with some treble loss, still in the plus-minus 1dB range, "Spitzenklasse".
At higher volume the left channel goes into slew limit and the right channel goes bananas.
 

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Hesener
Realy nice
Mine soon ?

Tanks for the caps info same way out of my budget but....

Scary stuff about cartriges being fried
I wonder how the my elitte survived 3 years on a INA Lt 1028 I designed
Probably I am not the only one now.

One thing came to mind
Would a very small voltagge (I mean very small) change the way a cartridge sound
Afer all is a coil next to a magnet.
I going to sleep on that now
 
AX tech editor
Joined 2002
Paid Member
[snip]
One thing came to mind
Would a very small voltage (I mean very small) change the way a cartridge sound?
Afer all its a coil next to a magnet.
I going to sleep on that now

Probably similar to DC offset on a speaker?
The DC offsets the coil from the exact center of the magnet (or vice versa) so with higher levels, the coil reaches the magnet edge on one side before on the other side. You get distortion, 3rd in this case.

jan
 
AX tech editor
Joined 2002
Paid Member
Alfred, that looks very good. I am eager to know if it works and how it sounds. How is the noise ? Do you also use an EMT cartridge ?

Jan, is that not 2nd because it is asymmetric distortion ?

Bksabath, an INA configuration should not have much input offset.

Uhhh, I believe it is 3rd, maybe should call it 'symmetrical distortion' from asymetric positioning?
Take a sine, squash the top and pull out the bottom, isn't that 3rd?

BTW Alfred chapeau!

jan
 
Third is higher when your driver is not balanced right, but Voice-Coil DC add primarily 2.order harmonics reason is the the two things are different.. In misalignment you get different mechanics like the spring out is different from the spring in...and thus 3.order distortion climbs.
The DC counteracts this and the measured distortion increase is for small offsets negligible, and primarily 2. order increase, but for larger offsets a combination of 2. and 3. order increase..as the mechanics again starts playing a major role..
 
The differential feedback offset cancelation circuit that i have introduced allows not only to cancel the input offset but also can be adjusted in such a way that the offset can be made positive or negative. I made experiments with this and have published the results here. That was only done by listening. I will repeat that with measuring.
It seems that people are interested about what is going on here and nothing conclusive has
being published yet.
 
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Joined 2005
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Alfred, that looks very good. I am eager to know if it works and how it sounds. How is the noise ? Do you also use an EMT cartridge ?

You have mail.

This was using a DL103 cartridge, the Paradise sounds mighty fine. But that was just a short listening, fresh from the workshop - no burn-in, no finetuning, just wanted to see if music comes out... and it does!