MONO cartridge recommendation

My mono cartridges are Lyra Dorian Mono, Audio Technica AT33 mono and Shelter 501 mono. My understanding is that these are "true mono" cartridges in that they only respond to horizontal stylus movement, although the styluses are still vertically compliant. The Shelter is a single coil while the Lyra and AT33 are dual coil, which should reduce the tendency to hum.

I previously owned an Ortofon Quintet mono, which I believe is a strapped stereo cartridge (similarly to the other Ortofon cartridges), although Ortofon do describe all of their cartridges as "true mono".

From information I have gained reading various forums over the years (particularly from Steve Hoffman), it appears that:

- After 1968 most mono issues were pressed from stereo cutting heads and it is virtually certain that this is true for most recent mono reissues (such as the Beatles LPs)
- Using a mono cartridge on LPs cut from stereo cutting heads will generally sound worse than using a stereo cartridge, since there will be some loss of high frequency information. If you have a mono switch (or a Y-cable arrangement) you can tell when an LP was cut from a stereo cutting head since engaging the switch (or Y cable) will result in some loss of HF. If there is no difference, you can use a mono cartridge and there will be the usual benefits of lower noise and wider soundstage.
- The benefits of a mono cartridge will only be heard with pre-1968 mono records, and this will depend also to some extent on the stylus dimensions and the equalisation curve used.

For these reasons I only use my mono carts on older LPs that I know were cut on mono equipment - pre-60s and earlier. For recent mono reissues I use a stereo cartridge.

If I have got any of the above wrong, please feel free to correct me.

rossb, You've certainly thrown a monkey wrench into the discussion, if what you say is true. Can you cite some sources to support the idea that a mono LP derived using a stereo cutting head will react differently from a "pre-1968" or true mono LP (to take your own cut-off date), to the use of a mono cartridge? And what about modern mono re-issues of recordings that were made in mono back in the early 50s?  (So the reproduction chain is: mono master tape to stereo cutting head to mono LP.) There's a lot of those around and more coming available every day. Presumably, the mono signal after a stereo cutting head is re-derived by re-combining the stereo channels, which are actually identical to each other.

You're correct, incidentally, about the Ortofon Quintet.  The Ortofon website uses a lot of double -talk to make the reader think their mono cartridges are "true mono", but in most cases that ain't so.

@rossb It’s a bit more complex then that

For example, anyone purchasing ERC can be confident they’re using a mono cutter ...
https://electricrecordingco.com/about

... but comparisons with other pressings of the same material cut on a stereo large suggest that this isn’t always a good thing ...
http://www.coupdarchet.com/reviews.html

... which likely explains why if you’re cutting a mono disc these days you’re best off using a stereo cutter

incidentally and somewhat off topic I was discussing the virtues of mono playback with Tim de Paravicini and his assertion was that mono cutters offered superior high frequency response due to the lower weight and simpler construction

lewm, as I mentioned, the information I provided was based on reading from a number of forums over the years. There are quite a number of discussions of mono recordings on the Steve Hoffman forums (as there are here) and Steve (who is probably as knowledgeable as anyone on this subject) has made some comments from which I have derived most of this information, so I suggest you do a search of that forum.

folkfreak, thanks for those links. I wasn't aware that ERC used a mono cutter, nor was I aware that Coup d'archet use a stereo cutter, even though I own the Johanna Martzy set from Coup d'archet that is the subject of the review. It therefore makes sense to listen to this reissue with a stereo cartridge.

It's interesting that although discussions of mono cartridges and mono recordings come up frequently, they almost inevitably lead to more confusion than clarity. I don't claim to be an expert, so if anyone has any better information, I for one would certainly appreciate it. 

@rossb I also own all the Coup Martzy’s (I’m not so rich that I can justify ERC prices) and love how they sound with my Zero. They also sound good with my Palladian but somehow there’s more vim with the Zero which suits the material. Have you tried them both ways and liked the stereo set up best?

Some other works, such as the recent 45rpm Pet Sounds, seem to work better with the stereo cartridge. I have two arms and so can make comparisons easily. Still great to have the dedicated mono for the older stuff in any case.