Affordable Mono Cartridge For VPI Scout

The following is from the Audiotools.com site.
Pickups and stylii for the playback of Mono LP records
Modern stereo records have use a groove that is about 18µm, earlier mono microgroove records however had a groove width of around 25µm (usually slightly more than this or up-to 28µm), the difference is small enough to mean that you can usually play a mono LP with a modern stylus but for optimal results it's best to have a stylus especially cut for mono lp's and a true mono pickup (not rewired or a plain stereo pickup) and indeed a few companies make such pickups and stylii. Ortofon has the OM 10 Super repackaged with a 25µm stylus for the playback of mono LP's as the OM D25M, note that this is still a stereo cart and that this stylus is available separatly and will fit all OM, OM Super, OMP, TM and Concorde type pickups from the company. There are also SPU variants for this purpose and those are true mono pickups, namely the SPU Mono A, the SPU Mono GM, the slightly cheaper Classic SPU Mono CG25Di and the Classic SPU Mono CA25Di. Audio Technica has the AT-Mono 3/LP, it's a variant of the AT-33 like the 3/SP but has a full frequency range. Lyra offers the Helicon Mono MC pickup with a stylus for Mono LP's, it's a true mono unit and My Sonic Lab has the My Sonic Lab Eminent Solo which is a true mono MC unit as well. Expert Stylus has 25µ stylii that can be glued onto any cart (I belive they have variants for used with worn mono LP's as well). Note that while Grado offers at the least 2 mono pickups these use 10µm stylii and are thus usable with mono records but not optimal like the pickups here above, these are also not true mono pickups but rather stereo models wired in series.

I am no expert but much of what you just posted from Audiotools is incorrect...with all due respect.

The SPU and Lyra cartridges have two coils and are wired or oriented internally for mono use. They are not true mono.

The CG25Di (there is no SPU CG25Di) is a true mono cartridge with a single coil. The design hasn't changed since 1948. The Denon 102 is also true mono but with vertical compliance.

Additionally, the Lyra mono cartridges along with other modern offerings use the same stylus as the stereo version. I'll leave it up to everyone to determine whether they believe such mono cartridges are worth purchasing or better to use a mono switch on their preamp.

It seems nearly every modern mono cartridge is equipped with the smaller .7 stylii than what was used during the 50s (1 mil or larger elliptical). My personal preferance has been for 1 mil for less than perfect early monos and smaller .7 mil stylus does indeed work well for my monos that are in great condition or mid 50s or later into stereo era (whereupon, stereo cartridge with mono switch is used).

The Shilabe design appears to be very different and interesting.

Someone on audio asylum recently bought a Benz mono and really likes it. True mono and likely a good match to VPI tonearms.

I have never had a mono cartridge, started with a mono system but a stereo cartridge so do not claim to be an expert, was led to that site by thread on another forum, all opinions expressed by them are theirs and not mine. Correct info appears to be hard to get, one site has a mono version of the Audio Techina 33, the AT 33 mono for $375, on another site there is the apparently identical AT 3 mono for $175. As I said I played my monos with a Stereo cartridge starting in 1962 and can't remember anyone making a big fuss about it in the days when mono LPs were common. Some time ago I posted my disbelief that mono cartridges should cost twice the price of the stereo version. Despite the considerable outcry at my ignorance of such matters I persist in it.

I'm using a Benz Ace mono low output cart with my Scoutmaster and it sounds great.