Analog Magic Question

@billstevenson 

I have set up four cartridges using the Analog Magik software, and all four should be ideal using the standard resonance calculation, based on weight of tonearm and  cartridge compliance; however, all four fail markedly using the Analog Magik test LP.  This makes me wonder how valid the test LP really is…

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.

@drbond 

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.

Hi lewm,

It was late when I keyed that message.  Sorry for my confusion.  Yes the correct unit of measure for resonance is Hz. The actual measured values for the azimuth are 0.45 (left) and 0.48 (right).  These were the best (closest to each other) values obtainable after a lot of fiddling.  

Bill