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Old 18th September 2002, 05:18 PM   #21
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Default Re: TO TRANNIE OR NOT TO TRANNIE ?

Quote:
Originally posted by fdegrove
Folks,

Thanks for the input.
Guess it's all a matter of doing the ultimate balancing (no pun intended) act,right?
If that's the path YOU choose to take. Others take more extreme paths and seem to be just as happy. I wasn't trying to imply that any one path is universally superior to any other. Least of all my own.

Quote:
Up to you Steve to put that switch on the box where it can be reached.
Hey, why's it MY job to wipe the bottoms of those manufacturers who can't see fit to put the polarity switch on their preamps where they belong? If I do everything for them, where's their incentive to change?

se
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Old 18th September 2002, 06:43 PM   #22
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Steve,

Quote:
Hey, why's it MY job to wipe the bottoms of those manufacturers who can't see fit to put the polarity switch on their preamps where they belong? If I do everything for them, where's their incentive to change?
We all have to do our part now,don't we?
OK,I'll supply a couple of paper rolls.

Cheers,
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Old 18th September 2002, 07:28 PM   #23
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Quote:
Originally posted by fdegrove
Steve,



We all have to do our part now,don't we?
OK,I'll supply a couple of paper rolls.
*sigh* Oh well. At least it's a paying gig.

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Old 18th September 2002, 07:53 PM   #24
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Default Wiping the bottoms....

Quote:
Hey, why's it MY job to wipe the bottoms of those manufacturers who can't see fit to put the polarity switch on their preamps where they belong? If I do everything for them, where's their incentive to change?

One might assume your job is to provide real (and percieved) value in the products you produce and sell.... Thereby able to continue to earn a living, improving the commoweal of the audiophile community, and adding to our global economy.

Many very fine preamps are single ended, and users would like them able to provide balanced outputs. Similarly, phase inversion is difficult, if not impossible without a topological change, to implement in many of these pre s, and those trannys provide that ability with a dpdt switch or relay. As a self avowed 'Zen Hedonist', one might think the ability to provide (with the proper secondary windings) single ended and balanced outputs, as well as (remote) phase reversal would interest you.

Certainly, it is not my place to 'teach my grandmother to suck eggs', and I assume your comment was made with tounge firmly planted in cheek (who's I won't hazard to guess).

With regards to your dissmissive posts on the benefits of removing insulation from electrolytics, wouldn't empirical verification (Hawthorne effect or not), consume less energy?
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Old 18th September 2002, 09:36 PM   #25
dice45 is offline dice45  Germany
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Default MC trannie comments and then back to origianl topic

All,

no, i do not think a Jensen wins against a piece of wire. but the the wrong piece of wire can spoil a preamp's sonics so completely that i won't listen to it anymore.

Therefore i said, the right piece of wire is always better than a Jensen 346.

Then:
the 1:4 ratio of the Jensen JT346AX is sufficient to bring a medium output MC to almost MM level and who really cares about the few missing dB?.
A Denon 103 has 0.3mV RMS -> JT346-AX -> 1.2mV rms for 0dB and many audiophiles consider this as sufficient, they also connect HO-MC cartridges with 1 or 2 mV to their MM input and are happy with it.
In 1:12 configuration almost any MC cartridge with between 0.15 and 0.4 mV achieves between 1.8 and 4.8 mV for 0 dB which is even closer to nominal 5mV for MM . So the JT346-AX covers all MC-cartridges except a few exotic ones like some AudioNote IO or Ortofon MC2000, ... , MC 7500 and such; i have report form a vdHul Kolibri owner who is super happy with his JT346-AX; he says that gain is a bit low but trannie impedance is just perfect. The Kolibri has lower output due to its missing front pole yoke but source impedance is like other Hul cartridges, so i was informed..

Then:
absolute polarity is a must IMO.

Now, enough talk about trannies and all possible analogue board talk. But it certainly was not my intention to help to threadjack this topic, i just wanted to get the heat out of a fruitless discussion.

I would be happy if the original cap skinning topic could be continued here where it belongs (i am curious and personally interested in the topic) and maybe we get some reports about actual experiments and how cap skinning and sonics are related and how dramatic or marginal the sonic impact of cap skinning is. Maybe even the color of the plastic has some influence? ... Dieter Ennemoser would say

Tomorrow i will split the thread into cap skinning and MC input topologies and we can continue both discussions in the particular thread and board.
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Old 18th September 2002, 09:37 PM   #26
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Default Re: Wiping the bottoms....

Quote:
Originally posted by pmkap
With regards to your dissmissive posts on the benefits of removing insulation from electrolytics, wouldn't empirical verification (Hawthorne effect or not), consume less energy?
I made no dismissive posts whatsoever on the benefits of removing insulation from electrolytics.

You're either confusing my words with the words of someone else who did make dismissive posts or you simply haven't read and/or comprehended what I have written.

se
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Old 19th September 2002, 12:03 AM   #27
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Default Re: TO TRANNIE OR NOT TO TRANNIE ?

Quote:
Originally posted by fdegrove
But I think Eric means he must have a way to check and control absloute phase of his media (CD,vinyl etc.).
It's a shame but all too many recordings are made with absolute phase reversed.
And no,I don't even want to think about all those multi miked acrobacies where they didn't even bother to check each feed's input phase...
Frank, yes you are correct in that the reason for the reversing switch is to control AP out of the loudspeakers.
In discussions with customers, I have confirmed the condition where on a CD, say 5 tracks are recorded in one polarity, and the feature (top 40) track is inverted.
This gives the condition where 5 tracks sound wrong and 1 correct on the CD owners system, who then takes it around to a friends place and the opposite condition applies (5 correct, 1 wrong).
Even the great un-washed on low-fi systems notice this problem, but of course do not know the reason or cure.
And with multi-miked cockups, at least you can get the vocals or drums correct and a more pleasing overall resultant.

Eric.
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Old 20th September 2002, 02:07 AM   #28
dice45 is offline dice45  Germany
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Folks,
the absolute polarity switch has to be on the front plate, not inside. Any each record (side) has to have a + or - mark on it. That's how i observed it at Allen Wright's place (who demoed the AP thing to me), that's how i will do it once my preamp is up and running.
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Old 20th September 2002, 12:42 PM   #29
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Quote:
Originally posted by dice45
Steve,
what you say above i can follow and i am with you as far as Jensen trannies are concerned.

I have a pair of Jensen JT-346 as MC input trannie. Except the right piece of wire, this trannie is the best MC input device i came across so far. It is expensive but does make up for it partially by not needing a power supply (and by providing potential isolation for the case i want to have my input grids at -100V.... ). TME an active MC headamp needs dramatic effort for the power supply, preferable NiCd batteries and all the hassle keeping them properly loaded.
Dice,

power supplies are not that critical like you suggest with active MC inputs. No need to take NiCd batteries. Take e.g. the Naim MC phono stage, which is considered as the best of the world by some Stereofool writers, it is powered by integrated LM317T power regulators (though, there is some more filtering behind the regualtors). And the Linn Linto has even a SMPS for getting >80dB S/N-ratio for MC input.

IMO, there are other concerns with MC inputs: When using a MC input without transformers, the worst thing one could do is to take an existing MM stage and then adding an extra 20dB gain stage at the input. When you do it that way, you have the combined sonic flaws of the MM stage plus those from the MC stepup stage. My conclusion is, that a MC to line level stage has to be designed as a whole, if it should reach the uppermost level. Better not take care of the artifical MM input interface level.

The Jensen is in fact the best xfr for MC that I know, and what is more important, it is your only choice, if you have a very low output cartridge with output of 0.2mV or less. The reasons for this is on one hand the noise limit for active devices of app. 1nV/Sqrrt(Hz) (some devices are a bit better, but not substantially), on the other hand thermal drifts, which will mask the signal in the bass frequency region.

regards,
Hartmut
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Old 20th September 2002, 10:17 PM   #30
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Hartmut,

I would keep an open mind?
I shouldn't apologise for my believe that any amplyfing stage IS indeed in the signal path?
If there's going to be a place where it's going to be audible it will most likely be this one?
Furthermore I believe if ayone is studying the effect of a PSU on a circuit,this would be a nice place to start?

Quote:
power supplies are not that critical like you suggest with active MC inputs.
If not here then where?

It's not because the press has an opinion that I would believe it.
People all too often seem to overvalue the merit of the media.

Quote:
IMO, there are other concerns with MC inputs: When using a MC input without transformers, the worst thing one could do is to take an existing MM stage and then adding an extra 20dB gain stage at the input. When you do it that way, you have the combined sonic flaws of the MM stage plus those from the MC stepup stage. My conclusion is, that a MC to line level stage has to be designed as a whole, if it should reach the uppermost level. Better not take care of the artifical MM input interface level.
To some degree,yes.
If though,there's any place for a more then good PSU it's gonna be here,lessons learned here deserve to be implemented futher down the preamplification stage.
In an ideal world pls design for one (MC) or (MM) the other,that's easier ,for sure.

Cheers,
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