Mono Cartridge Question


You chaps have watched me struggle with the issue of my London Decca Reference being irreplaceable, and then joyfully learning that John Wright has a successor after all. You have seen me buy and test three other MI designs (Nagaoka MP-500, Grado Statement3, Soundsmith Sussurro MkII) along with my older MC cartridges (Ortofon Kontrapunkt C and Benz Micro Ruby 3). Since those struggles have led me to owning two SME turntables and four tonearms, I am now torturing myself with the question of whether one of those four should be home to a dedicated mono cartridge. Remember, I only have one ear and cannot hear stereo at the best of times. A mono cartridge for my few dozen mono recordings would be a matter of reduced surface noise and possibly some improvement in dynamics.

I can get hold of an Ortofon Cadenza Mono (two voice coils so not true mono) for about 1600CDN, and a Miyajima Zero for 3450CDN. So the question is this: am I mad to even think about it? Money is not what it once was before I retired. There is no opportunity to go and hear these before purchase, without spending much more than purchase price on travel.

Shall I "make do" with my rather good stereo carts for my mono LPs or is there something better waiting for me when I get out those Parlophone Beatles LPs?

 

dogberry

@wallytools 

Hey JR... I agree 100%...  there is no chance of a conical tracing a purely lateral cut groove without adding a vertical component to the movement.  IF there is no vertical compliance something has got to give and it ain't going to be the diamond in the short term.  Many people who have moved from a conical to an advanced profile have noticed that many of their noisy original Blue Notes magically have a new lease on life.   

dave

The AT 33 mono has a 0.65 conical stylus with vertical compliance which is why anyone can play a stereo record with this mono cartridge. I had a Grado mono with elliptical stylus and without vertical compliance and it destroyed any stereo record in came into contact with.

@goofyfoot 

playing a stereo record with a "no vertical compliance"  mono cart does indeed tend to end badly.  It is important to understand why this is the case.  In a stereo record, the information common to both channels is cut in the lateral plane and the information unique to each channel (stereo) is cut in the vertical plane.  Playing this back with a generator with coils oriented at 45° to the record surface presents the complete stereo image.  It is the vertical (stereo) info that takes the hit when played with mono cartridge with no vertical compliance.  

As JR has pointed out playing a high frequency mono signal with a conical profile also creates a vertical component so the same thing happens but to a lesser degree.  The results of this are not as dramatic as the results of your mono Grado on a stereo cut but the effect still happens.  Over time, this is not a great way to treat your precious early original mono recordings.

The case of your grado having an elliptical profile  (or any other advanced profile) does not make things instantly better.  The problem here is not the shape of the profile but the lack of vertical compliance.    I actually believe that if not properly aligned, once the advanced profile is introduced to a situation with no vertical compliance, things can be even more damaging than a conical even on mono cut records.

dave

No mystery about it, if you use a mono cartridge with no vertical compliance you have to be careful to never set it on a stereo record. Or, you can use a stereo design made in a mono version (hopefully with the magnets mounted 45° away from usual as described above in my chat with Peter Ledermann, rather than simply strapped coils to sum both channels) and it will have the vertical compliance so that a mistake will do no harm. Those are the choices.