Mr. Karsten,
How, in layman's terms, would one go about "ringing" a cartridge with a square wave and observing the waveform? Are you talking about a special test record and an oscilloscope, or feeding an electrical signal (square wave)into the cartridge and viewing the returning signal?
Is this something that the manufacturer could do to give a precise recommended loading? I ask this because some manufacturers recommendations fall into a huge range (I believe my Lyra Titan came with a recommendation of 100 ohms to 47k ohms) while others give an incredibly precise figure, such as the loading recommendation for Allaerte cartridges. |
Larry, ya know, that's something I've often wondered myself- not only how manufacturers arrive at their loading specs but also why more of them don't do anything at all. This is a technique that does not require a test LP, or even a turntable, and is something any manufacturer could do.
One thing to be aware of though is that individual units, especially those that are hand-made, will differ from one example to another. My thoughts are that the manufacturer could bother to chart the critical damping on the same sheet of paper that the bandwidth is charted on, included with the cartridge itself when you buy it... sure make my like easier- people are asking us for cartridge loading values all the time! |
This loading question was a concern until I received an answer from Graham Tricker Tron designer. I have an Allaerts Finish cartridge and Jan recommends exact 845 Ohm load, so I asked Graham to do so with the Tron Seven Tube phonostage. Here his answer: " the Seven you have is set for 117 ohms wich it presents to the cartridge. Don't get hung up on the "loading" issue. It is a much misunderstood subject. Loading is normaly quoted for solid state electronics and can only be set by putting a resister directly across the signal path. This degrades the performance by a huge margin. The Seven is transformer coupled so the loading works completely differently and there is no harmful resistor across the cartridge coils. Jan Allaerts uses a Krell PAM 5 preamp wich is solid state, he has always used SS and there is only one way to load a cartridge with SS phonostages, that is with a resistor.
Loading is basicaly what the designer found worked best in his "test" system, and in his test environment ( listening room ). Loading is NOT calculated or worked out by measurements- it is an arbitrary figure made by listening tests. This changes in individual systems so there is no one correct setting. Also I have found that it is not a good idea to load a cartridge, as it is like putting a lot of weight in a car compared to driving the same car without any weight fitted. As you will know the car performs much better the lighter it is- same sort of thing with loading really.The more you load the cartridge the worse it sounds. Also the Seven is AC loaded so there is no harmful DC component interfering with the fragile cartridge coils so it is allowed to perform at it best without external influence. TW Acustic did some experiments with different loading values on the Seven and found it made no difference at all."
My Allaerts "845" ohm is paired with the "117" ohm Seven and is a great match. |
>>As you will know the car performs much better the lighter it is<<
That's a bad analogy. The car may accelerate faster but not handle as well without proper weight and weight distribution.
I hope Ralph addresses the other technical errors and misunderstandings in your post. |
A Formula one performs better than a truck :-) |
Jloveys, when you can measure a thing in audio, and also hear the same thing, then you have a powerful correlation that cannot be denied. Critical damping of any inductive device, whether it is a coupling/setup transformer, phono cartridge or tape head is an excellent example of such a correlation. Putting a resistor across an inductive device to effect Critical Damping is quite beneficial. Harmonic distortion is reduced, revealing more detail while simultaneously producing a smoother sound, and bandwidth is extended while simultaneously flattening the frequency response curve. These effect are easily demonstrated by measurement and listening tests. As an example I've included a link to the Jensen transformer website; Jensen is one of the world's leading manufacturers of MC step-up transformers (and other transformers as well; they have been in business for decades). On the page of the link you will see a pdf that can be downloaded that shows the various loading values to be used depending on the phono cartridge in use. http://www.jensen-transformers.com/mc.htmlWhoever you were communicating with regarding this issue is misinformed and missing out on getting better performance. |
Jloveys, that might be true on a track. But trucks are intended for use on the road, something that Formula cars suck at- their engines are not tractable since they are intended for power at high rpm. Additionally, many trucks will handle and ride better with a bit of a load...
Do you see now that its not a good analogy? If you want to use cars as an analogy, an unloaded cartridge is like a car with no shock absorbers- it will ring (bounce) and oscillate with any input. A loaded cartridge is like a car with tuned gas shocks- the output will reflect only what is on the surface of the LP. |
My post was only the exact answer that the designer of my phono preamp gave me because I was curious that the load phono is not matching with the cart. The entire phonopreamp was build with that cartridge in test, and when I hear the result it is quite amazing, dead quiet, detailed, dynamic and I realy don't see how to do better.I am no audio engineer but I am very fussy about s high quality of sound in my system.. Tron is equivalent to Tom Evans in england I heard both and like both. TW Acoustics (Raven TT) use Tron as reference. So I think that Mr Tricker is a respectable engineer and what he says must be taken with consideration.
Even if what he says doesn't match with your audio preconceptions it might be interesting to see why he says that load with tubes is less important than with SS. And why his phonopreamp is sounding so natural. Like music. |
Boy oh boy, it is really mounting here... Wagering on the outcome of Fail vs the world... I've gotta go with the world. LOL. |
Everything I've said is correct Zbag.
OTOH, you've been wrong consistently as pointed out by Ralph, Raul, Jonathan, Tvad, me, and every knowledgable person.
However, you seem to excel at casting aspersions, name calling, and insults in general. Those seem to be your strengths as you consistently duck the issues at hand and divert attention from your lack of understanding with snide remarks and worthless posts.
How's that white paper coming along? |
At one time we used this forum as a learning tool.Now we have someone like Zieman come on board,make statements without basis and tries to take jabs at others whom are much more knowledgeable.Fact is the only white paper Z is familiar with is hanging on a roller in his bathroom.Or is it his outhouse?? |
You forgot the entertainment value! Glad to see you and Raul have made up. Two peas in a pod... LOL |
Jloveys,
I will have an opportunity this weekend to play around with a friends Tron Seven. Another mutual friend has it while the owner is out of town. The "agenda" for this weekend is tube rolling. My friend has a big selection of 12AX7s as well as the other tube (can't recall the exact type) which is roughly the equivalent of a 12AU7. I will be able to contribute a Telefunken ECC803S to the experiment. The friend who is now playing with the phonostage has had it in his possession before and really likes this phonostage (used with either a Lyra Helikon or Transfiguration Orpheus)>
I read your comment, above, about loading for the Allaerte cartridge. I can understand that the manufacturer has loaded the secondary of the transformer feeding the active stages of his phonostage optimally (one needs to dampen the transformer ringing), but, to me, there is room to optimize the loading of the cartridge by choice of the proper resistor in parallel across the primary. My own phonostage (Viva Fono) also has a transformer at the input. I have experimented with loading across the primary and have found that it makes a difference. The difference is not as dramatic as changes in loading in my solid state phonostages, but, there is a difference. The high numberic value specified by Allaerte suggests that it should not be loaded down very much (good thing given its extremely low output), so I can see how no loading of the primary works for you, but, I am a bit skeptical about the universal claim that loading would not make a difference with this phonostage.
The owner of the Tron Seven is also an owner of a Tron Jubilate amp. The designer has also said a lot of things to this owner about how performance of the amp has been optimized, but frankly, the amp sounded like crap to me in several different systems. It was only after we did some tube rolling, discouraged by the designer, that the amp sounded pretty good. I am just a bit skeptical about things the designer of this gear says (he also had a lot of excuses for the amps multiple power supply failures). |
Larryi : thank you for your comment. The tron seven designer encouraged me to do tube rolling with this unit. I tryed first NOS Mullards 12AX7 wich improved the sound but a little too lean to my taste. The best results are with NOS Telefunkens 12AX7 in my system. The output buffer 12AU7 is already fit is a NOS GE USA. I will be interested in your week end discoveries. I will also try to put a resistor to achieve the 845 ohms for the A.Finish. Who knows, it can improve even more the sound, but this cartridge/phono couple is made in heaven.
Best regards. |
Jloveys,
Perhaps you should ask Allaerte about the right resistor to achieve proper dampening of the cartridge. I bet the value is different from the 845 ohms specified, given that the primary of the transformer represents a load different from that of other types of phonostages so the proper value might be different. If Tron supplies you information on the turn ratio, etc. of the transformer, I bet Allaerte can give you some suggestions.
The other alternative is to just experiment with different values. This should be relatively easy to implement. Just solder in a resistor between the hot and ground tabs on the back side of the RCA jack going into the Tron.
By the way, if the Mullards sound too lean in your setup, I would bet that the ECC803S would be EXTREMELY lean to you (a good thing, perhaps, given the CRAZY price for 803S' these days). |
If you don't have Tele ECC803S in hand it is an extremely expensive price for an experiment ! The classic ECC803 are wonderful here. Have fun and happy listening. |
a new topic is probably in order since we are veering substantially here, feel free to start it if you want and I'll toss in my thoughts.
(are there moderation / splitting of thread possibilities here?)
dave |
Oops sorry, I meant classic ECC 83 ... |
Hi Ralph, You mentioned it was easy to do above, would you mind going into more detail? I started a new topic called How do you know what to damp? and it would probably be best to post the method there. thanks dave |
Another obtuse response Z and devoid of contributory value.
You've not addressed any of the issues.
Again.
Raul knows the material well in discussion here. As I do. As Ralph does. If that's "2 (or 3) peas in a pod" I consider it a compliment.
How's that white paper coming along? |
Still waiting for that white paper Z. |
Jloveys,
I did not get a chance to hear the Tron 7 in my own system, but in my friend's system, I got to hear it with two different sets of 12AX7s. I did not find the Mullards too lean, as you found them, but, they were extremely phasey sounding, particularly so with reproducing the piano. It was so phasey sounding that it almost sounded like the phasing of the two channels was off (except the center information was reasonably coherent).
I much preferred the Amperex Bugle Boys that were substituted for the Mullards. My friend thought that Telefunken 12AX7/EEC83 was a bit too lean in his setup. I did not get to hear that tube, nor some of the substitutions he tried with the other tubes in the unit.
With the Amperex, I thought that this was a very good phono stage -- musical, reasonably dynamic, and dead quiet (my friend's speakers are 105 db/w efficient so noise is easy to hear). |
Very interesting finds, guys ! What are those speakers your friends own? Not so easy to have Amperex Bugles here but worth the searth. Thanks. |
A real crime in the making |
Jloveys,
The friend borrowing the Tron Seven has a system cobbled together from an ElectroVoice system (15" woofer with a folded horn, horn tweeter) and a huge multicellular midrange horn and compression driver of different manufacture. He has a big range of amplifiers. I heard the Tron mated to a custom-made tube linestage feeding a custom-made pushpull 45 amp, and on a different day, the Tron feeding a Levinson No. 32 linestage and a customized commercial solidstate amplifier. The phono cartridge was a Transfiguration Orpheus.
The owner of the Tron Seven has an older pair of JBL speakers and the Tron Jubilate amp and the Ortofon Per Windfeld cartridge. |
Zieman,
Still waiting for the white paper you promised us.
Thanks. |
Hi,
I have upgraded from a Jubilee to a Windfeld and it CLEARLY needs a HIGHER -- much higher loading to sound open. I can only go to 1k ohm on my GCPH but think it can still take more. 500 ohm sound already 'crammed in'which was more than a good thing for the Jubilee. I run it on a SME-V with SME 10 tt. GCPH phono-pre, SME vdH Silver phono cable. Rest is ML 326S, PASS 350.5 and Burmester 961. |
Axelwahl, How do you like the pw compared to the Jubilee? Is it worth the extra bucks? I thought Ortofon marketed the PW as kind of a super-Jubilee, so it is surprising that you are finding that the PW needs a very different load resistor. Thanks. |
Hi Lewm,
How much better do I like the Windfeld to the Jubilee?
If you like your music more resolved e.g. like Lyras, and have better, firmer bass, plus a more 'natural' (more complete?) sound than an e.g. Lyra Dorian the Windfeld has it --- but refer back to my system which is highly resolving. The Lyra Dorian would sound more 'skeletal', less 'natural' by comparison --- as would the more pricy ones as is often mentioned.
Is it worth the extra bucks? This depends on the rest of your system i.e. it may be that it will not show that difference (better top and bottom, keeping the 'nice' Jubilee mids) that much in terms of resolution, naturalness and 'cleaner' bass.
Is the Windfeld loading surprising? Maybe not, since more lately some top MC's give nice results with 47k! Why would that be? I think it has to do with the flux-damping, which prevents the trebble lift going over the top --- only explaination I have come up with. I found 1k loading to sound right on, even better than 500 ohm as was used by Dirk Sommer also having tested it recently (he did not have 1k ohm available on his Einstein and sounded just a little less enthusiastic, when reading between the lines). Also know, that DS is an SPU fan i.e. highly dynamic and maybe a bit more 'chirpy' than 'neutral'. The higher loading (1k) will just take you in this direction.
One more interesting (more confising?) point: The factory guys (Ortofon) say the >10k ohm in the brochure was a misprint and should have read > 10 ohm. Mind you, THAT changes not much, since 1k is also > 10 ohms, right?
I have tried it with 47k and got problems with the SME-10 motor controller (3 phase, 40 Mhz clock etc.) coming through as 'line-noise'. This might be no issue with a different tt, and/or phono-stage, so I can't say much positive on 47k loading - AND it sound too 'fluffy' what you would get when loading e.g. a Jubilee with 1k.
I hope this is of some help.
Best,
Axel |
