Regards, Halcro:
No need to respond ("Dover and the Professor will have to wait...."), it seems you already did, subsequent to Kirkus’ entry, 10-11-2014:
Halcro wrote:
"Many thanks for your thoughtful Post (as usual).....and it has made me realise how wrong I am about the importance (or lack thereof) of the Arm/Cartridge Resonance…..😲❗️
I’m really kicking myself now because I’ve done a great deal of thought and study on the subject of Structure-Borne Feedback as it relates to Audio and yet…..because I fortunately don’t suffer from it myself…..I completely ignored its possible relationship to the Arm/Cartridge Resonance..."
Two days later Fleib wrote:
"Generalizations, half truths, and oversimplification lead to erroneous conclusions even if they work. Rules are made to be broken and it’s results that matter.---
"How is it that Halcro can track almost anything with a resonant frequency below the recommended range, magic? It’s because his set-up isn’t easily excited by acoustic/mechanical impulses and he probably doesn’t play severely warped records."
Atmasphere points out "The adage that rules are made to be broken is in itself a generalization."
Offered was a thread in which the exchange of evidence and experience were deliberated in a thoughtful manner. Falling back on conventional "wisdom" is easily done, those who dare to examine certain of those conventions are not always celebrated. Mea culpa.
In this thread tunnel vision is recently in evidence, for perspective the entire thread needs to be reviewed. The title of this thread is on its own a generalization. It questions audiophile convention and stirs controversy. Although I don’t agree with all comments (ahem) I’ve been driven to actually think and for that I’m somewhat resentful.
Keep up the good work.
Peace,
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@halcro Now I'm off for our regular Thursday 'Lunch With The Boys' where we sit around for three hours devouring bowls of Laksas and an entire bottle of the finest blended Scotch between the three of us 🥃
Halcro (Henry) Maybe you should send some of that good scotch to Mijostyn. The stuff he is drinking has put him in some bad mood. Good that the mods are here. |
I missed the Post Chris.......Perhaps the Parrot was the rare NORWEGIAN BLUE and has "joined the Choir Invisible".....? |
As I've repeated numerous times......I was moved to begin this Thread, not to disparage the science behind the topic......but because after 40 years in Audio, and the last 12 years testing and listening to hundreds of arm/cartridge combinations.....my ACTUAL experiences could not match what the 'science' was predicting 🤔When I say this.....I don't mean that it was a 50:50 proposition so that the science worked in so FEW cases that I could live it 🤗I mean:-
- I NEVER had a cartridge 'jump' from the groove
- I NEVER had visible woofer pumping
- I NEVER had audible mistracking
- I NEVER had over-bloated bass
- I NEVER had 'missing' bass (unless the cartridge was deficient)
Good science requires 100% applicability and predictability.Bad science should still provide (at the very least) a majority applicability 🎯When the 'science' provides zero correlation to the listening experience of even one shmuck (like me)....it needs to be questioned. Propitiously......this LINK landed in my Emails last night and deserves a reading (complete with the graphs, and Test results which aren't included in the following quote.
This is the second post in the series on low frequency interaction between the tonearm and the cartridge.
In our previous post, we've formulated The Plan, and done the first bullet point: measured the Ortofon/Jelco combo from 5 Hz to 20 kHz, and put it all on two charts. What the measurements showed was a bit removed from what the calculations suggested.
Today, it's time for the second part of The Plan:✓Make sure our test rig is working fine and is picking up both high and low frequency resonances. We'll measure the low frequency set with it, and superimpose it over the usual 20Hz-20kHz sweep.2Change the cartridge to the one with different compliance, and see what the effect on the low frequency resonance would be.3See what the low frequency content of the usual LPs looks like. We'll use some nearly unplayable LPs from our collection to try and get the effects of warps and excentricity.4Do the analysis of the data and see if there are some recommendations to be made on matching tonearms and cartridges.The Setup
In addition to the Ortofon SL-15E that we've employed in the previous post, we will use our old acquaintance the Denon DL-103. Its compliance is specified at 5⋅10−65⋅10−6 cm/dyne (5 µm/mN). This fits well with the required downforce of 2.5 gram. Unlike many other cartridges, there's no doubt that Denon's suspension is actually quite stiff.And to give an opposite perspective, a Shure M97xE. While it is shown with its brush down, all our measurements were done with the brush up and the downforce correspondingly decreased.
Shure specifies the compliance at 25⋅10−625⋅10−6 cm/dyne, but it's probably much higher. Various moving magnet Audio Technicas are specified as having 40 (!), and Shure definitely has a much softer suspension. The lower required downforce (less than a gram for Shure versus 1.8-2.2 g for ATs) supports this.
The MeasurementsThe accepted formula gives us 12 Hz resonant frequency for the Denon.
So if we take it at face value and plot Denon and Ortofon low frequency resonances together, we should get something like this.
Of course, the amplitudes might be different, and the curves would not be so neat and unbroken. But we definitely would see the frequency peaks, and we would see the frequency shift. The resonant peak must shift in frequency.
I've zoomed the charts on the 5-25 Hz area and made the X axis linear.
And what do we have in reality?That doesn't look like shift at all. Maybe the vertical resonance would?
We see the change in amplitude all right, but the frequency shift is missing. This does not look much like resonant behaviour.
Extraordinary findings require extraordinary evidence, right? So let's see if using the Shure would result in the shift in the frequency of the resonant peak. Remember, specified lateral compliance of Shure is the same as Ortofon's, but we expect it to be higher. So our peak should be similar with the blue trace's, or slightly to the left. Right?You can argue that the 6 Hz hump is the peak we're looking for, but this is splitting hairs. The main difference is in the lower overall motion, not in some particular frequency.
For completeness, here's the vertical comparison chart with Shure included.What did we discover today?Looks like the low frequency behaviour of the cartridge/tonearm combination is shaped more by Newton's third law than by the compliance resonance. Modern cartridges (meaning all those built in the last 60 years or so) have too much suspension damping and non-linearity for the resonances to dominate.
I would stop at this today, leaving conclusions proper until the last post in the series. This is heady stuff, and I fully expect some people to become very upset.
Besides, we are not done yet. So far, we're only studying the motion that is excited by the artificial test signals. What would happen when we expose our combinations to actual real life records? That's the topic for the next post.
I'm not claiming 'victory' as a result of this single publication.....but I AM claiming 'vindication' in QUESTIONING the premise contained in this Thread. |
Thanks again Professor.....but a lot of time has passed since I responded to Kirkus’ Post and I would like to clarify my thoughts since that time.
I also really want to address the points brought up by Dover, Thom and Chris as they are important.....however this will still have to wait as I need to prepare for this evening’s dinner party which will include the attendances of my Luncheon Buddies (and their spouses) 🍽
Conversation will of course be appropriate for the female company....although after even more whisky......it can become quite loud and raunchy 🤪
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