My VPI HW 40 w/Hyperion passed the test. I was laughing to myself thinking about this last night. First, no wonder my Technics sounds the best it has ever done. It has a brand new LVB installed, which is far better than the regular Black that it replaced which was also defective in any event. Also, like you, I wonder now how important the resonance test is. Or put another way, what are the practical ramifications of this failure? I thought it might be interesting to ask Ortofon for comment. I have been interested in their new tonearm anyway and wonder if replacing the stock Technics tonearm would offer an appreciable improvement on the GAE. In theory it should if the effective mass is low enough to render the resonance frequency of the combination using an LVB is in the 8-12 db range in both planes.
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After ruminating per our last exchange I decided to ask Louis at Ortofon for comment. I sent him a copy of my test report. He expressed alarm at the resonance result and asked if I was using an aftermarket head shell (yes a Jico) because in his experience the 2M cartridges are compatible w/SL1200 TTs. He stated that the measured resonance failure would result in miss tracking and audible distortion. So, I played through my Ortofon Test Record paying particular attention to the Tracking ability tracks and can hear no miss tracking. My conclusion parallels yours that the deficiency must be in the AnalogMagik test for this parameter. |
"In theory it should if the effective mass is low enough to render the resonance frequency of the combination using an LVB is in the 8-12 db range in both planes." As I am sure you know, frequency is measured in Hz, not in db. So it might seem you meant to write that the amplitude of the resonance is 8-12db. But the desired resonant frequency is also said to be in the 8-12Hz range. So I wonder what you actually meant to say. Also, further up the thread, you wrote "Azimuth L to R. 0.03% difference (note my VTA adjuster is frozen but visually it looks OK)". What does that mean? Does it mean that there was a .03% difference in interchannel crosstalk, in terms of db? That is a very very tiny difference that I doubt can be measured reliably. Some months or a few years ago, Dave Slagle was at my house, and he adjusted my ART7 cartridge to correct for its zenith error. To do that, he had with him a laptop with some sort of measuring program on it. But also we listened after each tweaking of zenith (made by twisting the cartridge in the headshell). There was a profound positive difference both aurally and by computer measurement, when he got the zenith optimized. I was really rather amazed. Since then, that headshell and that cartridge are permanently mated, so far as I am concerned. |
That can’t be correct. For this test you are playing a 1 KHz tone in one channel and measuring how much lower it is in the other channel. Lower is negative dB. -20dB is 10 times less and not so good -30db is about 32 times less and what better cartridges can do, or close to it -40dB is 100 times less and very unusual as well as very, very good You should typically be getting readings in the minus 25-30 dB range. The goal is for them to be as close together as possible with about .5dB difference pretty good. So for instance -27.7dB for L and -28.1dB for R would be .4dB difference so pretty good. The numbers you stated make no sense. https://www.analogmagik.com/azimuth
I assume Dave was using Analog Magik and using the VTA test if he has version 1. He has discussed this over at What’s Best. Version 2 has a Zenith test but I have V1 so haven’t used it. For V1 measure distortion with the VTA track, twist and measure until you get it as low and even as you can. Typically starting closer to 10% after aligning visually, I’ve found 2-3% to be really good. |
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