EFFECTIVE MASS:Here is a cogent, scientifically based and rational explanation

[Neil McCauley]

Of possible interest for those seeking a more practical than theoretical discussion of the subject.

http://theartofsound.net/forum/showt...449#post789449

[Barry]

There is no mystery about the concept of effective mass, and certainly no need to evoke the quantum mechanical paradox of 'Shroedinger's Cat'.

Effective mass is defined in footnote [1] of http://theartofsound.net/forum/showt...idge-resonance.

[Neil McCauley]

Hello Barry. You wrote: There is no mystery about the concept of effective mass, and certainly no need to evoke the quantum mechanical paradox of 'Shroedinger's Cat'.

Thank you. I'll let the author know about this. Presumably you read the entire article? Both he and I hope you weren't judging the 'book' by its 'cover.'

My suspicion (and I will check if you’d like me to) is that Mr. Owen would consider, possibly even welcome a robust mathematical debate about the efficacy of his perspective. I believe in academia this is known as 'Peer Review' Is that of interest perhaps?

I did in fact read yours. Am i right in thinking as the author you feel yours is the last word on the matter? I wasn’t clear on that point.

That said, yours is clearly a fine piece of work I must say. One observation if i may though. Unlike Mr. Owen's piece designed to be of assistance to the typical audiophile 'civilian' I was - in ignorance - unable to immediately see how your admittedly scholarly work would be of practical assistance to comparative novices like me. Did I miss something?

Your equation 1/(2π.√(19.5 x 0.000 01)) = 1/(6.283 x √(0.000 195)) = 1/(6.283 x 0.014) = 11.4Hz being a case in point.

The intention at our end is to provide a basis for a potential customer and retailer to engage in an intelligent and intelligible dialogue about the arm / cartridge interface rather than rely on conjecture and misinformation. The emphasis being on the practical rather purely theoretical. A benign education module if you will; designed to confound ignorance. Only the reader can judge how effective this is. I was, in my self-confessed ignorance, far from clear as to your target audience for your well-written piece.

Re the paradox of 'Shroedinger's Cat, both I and the author agree that there was no ‘need’ to evoke it. The intention was one of harmless relevant light levity and nothing more. I apologise if this offended you.

My perspective is that the two articles compliment each other. Sadly I lack the necessary intellectual horsepower to be able to determine - in isolation - which is superior.

Neil

PS: The Geoffrey Owen / Helius piece on this topic is now the most popular post in the previous 24 hours at www.hifianswers.com

[marec]

Hello Barry. You wrote: There is no mystery about the concept of effective mass, and certainly no need to evoke the quantum mechanical paradox of 'Shroedinger's Cat'.

Thank you. I'll let the author know about this. Presumably you read the entire article? Both he and I hope you weren't judging the 'book' by its 'cover.'

My suspicion (and I will check if you’d like me to) is that Mr. Owen would consider, possibly even welcome a robust mathematical debate about the efficacy of his perspective. I believe in academia this is known as 'Peer Review' Is that of interest perhaps?

I did in fact read yours. Am i right in thinking as the author you feel yours is the last word on the matter? I wasn’t clear on that point.

That said, yours is clearly a fine piece of work I must say. One observation if i may though. Unlike Mr. Owen's piece designed to be of assistance to the typical audiophile 'civilian' I was - in ignorance - unable to immediately see how your admittedly scholarly work would be of practical assistance to comparative novices like me. Did I miss something?

Your equation 1/(2π.√(19.5 x 0.000 01)) = 1/(6.283 x √(0.000 195)) = 1/(6.283 x 0.014) = 11.4Hz being a case in point.

Although I have no particular interest in this, nor any particular mathematical ability, I do not find this equation a special challenge...

Rgds

mark

[Infinitely Baffled]

Effective mass is defined in footnote [1] of http://theartofsound.net/forum/showt...idge-resonance.

Hello, Barry. Following this thread gave me cause to look at your learned article referred to above, where "effective mass" is defined in the first footnote. My question, though, concerns your second footnote, where you talk about identifying the resonant frequency of the arm/cartridge combination. You suggest the reader uses Bands 6, 7 and 8 on side one of the Hi-Fi News set-up disc to locate the resonant point. Unless there has been a re-pressing of this disc, with the bands in a different order to mine, the tracks you reference relate to fine-tuning the anti-bias setting. It is tracks 2 and 3 on side two which contain the frequency sweep that reveals the resonant point. Or have I completely misunderstood this subject and how I should be using my set-up disc? Regards. Gary.

[Rothchild]

I just wanted a quick read, do I really have to register just to read the article?

[Barry]

Hello, Barry. Following this thread gave me cause to look at your learned article referred to above, where "effective mass" is defined in the first footnote. My question, though, concerns your second footnote, where you talk about identifying the resonant frequency of the arm/cartridge combination. You suggest the reader uses Bands 6, 7 and 8 on side one of the Hi-Fi News set-up disc to locate the resonant point. Unless there has been a re-pressing of this disc, with the bands in a different order to mine, the tracks you reference relate to fine-tuning the anti-bias setting. It is tracks 2 and 3 on side two which contain the frequency sweep that reveals the resonant point. Or have I completely misunderstood this subject and how I should be using my set-up disc? Regards. Gary.

Hi Gary,

The information about the Hi Fi News test disc was taken from their web site. I assumed the information contained therein was correct and up to date, but it seems there is has been a revision and a new version of the disc. Thanks for pointing this out; I'll amend the article in The Knowledge.

Regarding use of the test record, again I assume the disc comes with instructions on how to assess the low frequency arm-cartridge resonant point.

[Infinitely Baffled]

Hi Gary,
Regarding use of the test record, again I assume the disc comes with instructions on how to assess the low frequency arm-cartridge resonant point.

Thanks, Barry. Yes, there are some instructions, but they are fairly scant. In the case of the resonant point it is reasonably obvious what is required, but some of the other tests are a bit vague, eg. Band Six, Side Two: "Residual System Noise - unmodulated grooves. Play at normal listening level and gently turn up the volume. If the noise level remains unobtrusive for most of the volume increase, then your system will certainly produce very little trouble at low frequencies. If rumble, or any other noise is detectable at normal listening levels, check out the mechanical parts of your turntable."
As far as I can understand, you just keep turning up the volume until valve rush and vinyl roar make it unlistenable! But the disc is nonetheless invaluable for some of the other tests (phase, channel balance, resonance etc.).

Thanks for the response.
Gary.

[Neil McCauley]

I just wanted a quick read, do I really have to register just to read the article?

Hello. We feel the need to point out that this one is far from a quick read inasmuch as it's an in-depth rather than superficial approach to the topic. We don't want to mislead you. Regarding the second part of the question, the answer is yes.

Thanks. Regards. Neil

[Neil McCauley]

Although I have no particular interest in this, nor any particular mathematical ability, I do not find this equation a special challenge...

Rgds

mark

Our guess is that you are not alone re this point. That said though, the objective of the Helius / Geoffrey Owen approach to the topic was to encourage a practical (is this another word for 'understandable') discussion between retailer and buyer rather than a more theoretical approach. Both approaches are, we feel, equally valid but neither are universally applicable it seems.

Two quotes (of many) from the late Richard Feynman are we feel appropriate in this context:

“The real problem in speech is not precise language. The problem is clear language. The desire is to have the idea clearly communicated to the other person. It is only necessary to be precise when there is some doubt as to the meaning of a phrase, and then the precision should be put in the place where the doubt exists. It is really quite impossible to say anything with absolute precision, unless that thing is so abstracted from the real world as to not represent any real thing.”

And …

“Pure mathematics is just such an abstraction from the real world, and pure mathematics does have a special precise language for dealing with its own special and technical subjects. But this precise language is not precise in any sense if you deal with real objects of the world, and it is only pedantic and quite confusing to use it unless there are some special subtleties which have to be carefully distinguished.”

Thank you and regards - Neil