Cartridge dynamic behaviour

[billshurv]

I am already beyond the minimum despite selling a few!


MM are my Kryptonite (hence this thread). Luckily exploring how to get the most our of these with the help of all here takes my mind off hunting for more. When I start a stylus shape thread all bets will be off.

 

[waltube]

I ask to Mauro, director of Audioreview, to put online the article.
I will send the link

Walter

 

[gpapag]

No, you are in error, in my opinion.

Walter, please pay attention to Bill’s comments on such an issue.
102 is too high a number (even he has barely reached the 99)

The passion, and the Hifi is a passion, hasn't rules.

Dr.Paul Janssen has catered for us all

George

 

[scott wurcer]

I
MM are my Kryptonite (hence this thread). Luckily exploring how to get the most our of these with the help of all here takes my mind off hunting for more. When I start a stylus shape thread all bets will be off.

I have 2 carts and the thought of shape shifting one scares me. My most recent obsessive behavior was an attempt to collect samples of every blue pigment on earth for my Asian painting so I understand the mentality. OTOH with the cart stuff I just want to help out.

 

[billshurv]

If I can work out a suitable set of tests and suitable music for samples (which someone always complains about) I would like to do comparisons of various stylii on the same cartridge. But that is for some way into the future as still have to finish the current work that George and Hans have started.

 

[gpapag]

If I can work out a suitable set of tests and suitable music for samples (which someone always complains about) I would like to do comparisons of various stylii on the same cartridge.

This means you will play the same track 2-3 times.
Horror!

George

 

[billshurv]

After you proved 100 plays actually improves things I have no fear of that!

 

[rickmcinnis]

There is a Swedish company SWAT making just an arm for 30k$.
This arm was tested by Stereophile as the best one ever.
Because of this test, the arm was sold more than a hundred times in two years time and is now succeeded by a slightly cheaper and an even more expensive version.

Since Stereophile is also very charmed by 10k$+ Lyra and Ortofon Carts, I would expect that alone for this arm it will already be 50/50 Lyra and Ortofon.
To my feeling, most buyers are US citizens.
In Europe there is hardly a a market for such extravaganza.

Hans

Mr. Polak,

I bet more of that stuff ends up in Asia than in the US. Sure some of it does come here but the Asian market sets the standard for extravagance these days.

 

[rickmcinnis]

A question for billshurv:

Have you got your TWISTED PEAR based AURAK up and running yet?

TP says they have re-ordered the boards so it is not as if anyone needs to be in a hurry BUT have you found out if this works well with the AURAK idea? I, too, would like a balanced output and this would make it easier to have something.

Curious if you are happy with it or still searching?

 

[gpapag]

Frequency response test of the fixed part of cartridge’s motor (coil and magnetic core).
Ten steps of excitation voltage.
New jig, E-MU 0404 soundcard, REW SW.
192kHz SR, 4M sweep, x8 repetitions, 3minutes per sweep, 1504 freq points data sampling (96 PPO).
1/6 oct smoothing, subtractive method at each excitation voltage step (cartridge response-short response in Excel).

George

 

[gpapag]

AKG P8ES_R channel
Audio Technica AT110E_R channel
Dual ULM65E_R channel
Ortofon Super OM10_R channel
Pickering 950EE/MKII_L channel
Shure SC35C_R channel

 

[billshurv]

A question for billshurv:

Have you got your TWISTED PEAR based AURAK up and running yet?

Hi Rick,


Short answer is (embarassingly) no. Life has somehow got in the way of catching up with my project backlog. But recovery plan is in place. Now in a way this has been a blessing as we've since discovered, thanks to Hans and George that some cartridges I thought would work really well with this don't. And the ortofon SuperOM, which does work is so far from the factory specs that it needs the loading rejigging. Should have it running soon.

 

[JP]

To my disappointment Ortofon has yet not responded to several emails with my friendly questions regarding their test record.

That leaves us to decide on our own whether this CV test record can be used for testing MM cartridges.
JP have you already found some time to play this record with different termination settings ?
To my feeling this record is OK. up to 40 kHz within +/- 1dB when played at 45rpm.
And we also have the preemphased CH Precision record, going within +/- 1dB up to 30 kHz.
When JP can confirm this FR, we could start closing the circle with validated records and equivalent circuits for 8 Carts to find the Tranfer Circuit for the Carts motor function.

Hans

Sorry haven't had time yet. Took on a couple favor 'table restorations that have taken my free time.

 

[rickmcinnis]

Hi Rick,


Short answer is (embarassingly) no. Life has somehow got in the way of catching up with my project backlog. But recovery plan is in place. Now in a way this has been a blessing as we've since discovered, thanks to Hans and George that some cartridges I thought would work really well with this don't. And the ortofon SuperOM, which does work is so far from the factory specs that it needs the loading rejigging. Should have it running soon.

Thanks for the update.

I figured you would have made more mention if you had.

I do know you have good excuses for not putting it together.

As long as the boards are not available - I do hope they were serious about restocking them - it is a moot point.

I am using a SOUNDSMITH Zephyr cartridge. I wrote a note to them asking about using it into a balanced input and have heard nothing. I hope this one is not one for the list of NOT GOOD for AURAK. I need a low compliance cartridge and there are not many of them, good ones, in the MM/MI world. Unlike you I am a one cartridge at a time fellow. Though, as you can see, I am a spendthrift.

I do look forward to hearing how it works for you. I will wait patiently to follow.

Thanks for all of the information your thread has revealed. I know you have had plenty of help but the one who starts something always deserves special credit. I should mention the kindness of Mr. Polak who has answered a few of my questions along with his thread dedicated to AURAK.

You know you are following a "good" thread when there are such great collaborators/contributors. This one has an all-star cast.

Thanks and take care,

 

[billshurv]

I should note that, although not yet a reason for the aurak delays I have a couple of voltage mode balanced circuits I am planning to try out after I get the aurak working. I believe the soundsmith it based on B&O MMC series so if someone knows which model we can probably borrow one to get it measured.


I only need to change 6 resistors to do the testing so I have no excuse not to crack on and see what happens.



I didn't really start the thread, I just pulled an interesting nugget out a discussion and the clever guys picked it up and ran with it . The thanks should go to all of them.

 

[billshurv]

Phase response

Not sure if this requires a dedicated thread, but looking at some of the generator performance calculations Hans and George did its clear that differnt loading schemes have a greater (numerical) effect on the phase response in the audio band than the level. Not sure on the audibility of phase shift above 10kHz, but aware Ortofon firmly believe that flat phase even if it means a 2dB lift at 20kHz is best.


Anything worth discussing/ investigating here?

 

[Hans Polak]

Not sure if this requires a dedicated thread, but looking at some of the generator performance calculations Hans and George did its clear that differnt loading schemes have a greater (numerical) effect on the phase response in the audio band than the level. Not sure on the audibility of phase shift above 10kHz, but aware Ortofon firmly believe that flat phase even if it means a 2dB lift at 20kHz is best.


Anything worth discussing/ investigating here?

To my modest opinion, we should first finalize the road where we are on by validating 1 or 2 LP's (JP where are you ?), followed by recording the FR of several Carts with these LP's.
This all combined with the equivalent replacement models may enable us to predict the phase behaviour above 10kHz.

Question apart from that is: what holds Ortofon still for acceptable as a phase shift above 10kHz in exchange for a lift, 1 degree, 5 degrees, 30 degrees ??

Hans

 

[billshurv]

I was thinking more at the moment to understand if it even matters so possibly could be tested by fettling a few digital files? I accept that for real MMs we are still far from getting the full answer to even decide what to do.

 

[JP]

Busy busy busy, but holiday week. Remind me what I was supposed to do?

 

[Hans Polak]

Busy busy busy, but holiday week. Remind me what I was supposed to do?

Hi JP,

This was the question:
Cartridge dynamic behaviour

Regards
Hans