Mono cartridge classification

Hesson11, I've posted comments on selecting stylus size relative to the records to be played here and elsewhere and thank you for your added descriptions. I've also read the suggestion that Lyra narrow profile styli are recommend for mono playback. But then I ask if the Lyra recommendation was for modern mono reissues (cut with current stereo cutter heads as apparently no mono cutters remain) as compared to original '50s monos cut with a wider groove? So far, I've not seen an answer to that.

Also, you include mention of Grado as an example of "mono carts (that) actually do produce a mono signal". My understanding is that a true mono cartridge will only pick up lateral motion, not vertical. Several sources have suggested that Grado mono cartridges are merely stereo designs that have been strapped internally for mono output. In other words, they still pick up vertical signals, thus would be more susceptible to noise. Have you found a confirmation one way or the other?

Lastly, I'm not aware of any manufacturer who claims a cartridge is mono simply because it has a conical stylus. Do you have an example? Many early stereo cartridges had conical styli, the current survivor being the Denon 103.

Thanks for checking me, Pryso. I need it! Still learning.

Here is a post by Jonathan Carr of Lyra that says Lyra listened to a wide range of mono recordings in developing their stylus. He says the records were both pristine and well-worn, but he doesn't cite the eras they represented. I assumed that by well-worn, he meant they listened to records from many eras, but he doesn't explicitly say that:

http://www.audioasylum.com/cgi/t.mpl?f=vinyl&m=418745

About Grado, I was careful to say that they produce a mono signal. As you said, I believe they are "mono carts" in that they are strapped to sum the L and R signals. Like you, I believe I've read that they do have vertical compliance, but I can't be sure. So they probably can't be considered TRUE mono carts like the Denon DL-102.

For your last question, the KAB website states that the KAB/Ortofon OM-1M is a stereo cart with a 1.1 mil stylus for mono playback. I believe this cart is the same as or similar to the Ortofon OM D25M, but I may be wrong about that. Do you know for sure?

I wish I had time to track down and post all the references I've drawn from——but I don't. So I hope others like you will continue to fact-check me. Not that we'll ever solve all the contradictions of mono! THANKS.
-Bob

Hesson11, thanks for the link to Carr's information. Nothing like going to the
horse's mouth! Here is information I posted on VA some time ago. Mr. Carr's
information seems to correct part of that -

"I believe you must first consider which records you will be playing before
buying a mono cartridge. From reading I've done, here are my conclusions.
Note this applies only to 33 LPs, not 78s. Dates refer to master cutting, not
performance date for reissues. This is a function of the groove shape created
by the cutter head.

Pre-stereo era monos (roughly '48-'57), select a 1.0 mil conical stylus.

Early stereo era monos (roughly '58-'68), select a 0.7 mil conical stylus.

Recent mono reissues (mid '90s to present), select a mono cartridge with a
modern narrow stylus profile.

Lyra may have been the first to promote narrow profile stylus tips for better
performance in mono cartridges. I suggest this may be true for playback of
the many mono reissues, but not as good for older originals. I've heard that
mono cutter heads are no longer available so reissue monos are now cut with
stereo heads, but with lateral motion only. This is not to say a mono cartridge
with a narrow profile stylus would not sound OK on earlier pressings, it
simply would not be optimal."

I've since purchased a mono Denon 102 but installation awaits the
completion of a new plinth for a two-arm table.

I'm not familiar with Ortofon cartridges so no help from me there.

If you think there are lots of contradictions with mono lps, start doing some
research on 78s! I have a 4-record 78 album of Louis Armstrong and the All
Stars at Town Hall, a very famous concert from 1947. I began researching 78
cartridges and that is where the waters really become muddy, and deep.
You've got to add speed and EQ variations to the various tip dimensions. At
least the situation was a little more standardized by the late '40s for my
album.

Thanks, Pryso. Your understanding of which styli to use for which recording era matches mine. Perhaps I got it from you! Have you checked out the Esoteric link I posted above? There's some pretty good info there that seems to match yours (and it's pretty clear, too!).

I'm confused enough about mono, so I'm scared to even think about 78s!

Not to open another can of worms, but do you use any kind of equipment to match the pre-RIAA EQ curves (Esoteric Re-Equalizer, KAB Souvenir, etc.)? I just use the tone controls on my integrated amp, at least for now. Works pretty well.

-Bob

Hesson11, I've looked into EQ devices, including the Re-Equalizer, but have not purchased anything as yet. I began a major change in my system last year, going to HE speakers and a 300B PP amp. I've also picked up a few cartridges following inspiration from Raul's lengthly post. But one component at a time, and after I settle on an amp (still evaluating), I'll choose a new preamp/line stage, then decide on the EQ. I don't have anything with tone controls but I've read they can work fairly well.

I do have several hundred mono LPs so optimizing their playback will be a high priority. Thanks for your interest and adding your thoughts.