Which Mono Cartridge at around $1,300.00?


I'm in the process of upgrading my well cared for Thorens TD145. I started by soldering in WireWorld phono cable along with getting a basic tune up. I want to replace my Grado ME+ mono cartridge with a substantially better mono cartridge. Currently, the tone arm is stock. My records are classical (orchestral, chamber, vocal, etc...) dating from the 1940's and 1950's so I've been cogitating on the Ortofon SPU Mono GM MKII or a low output Grado (i.e. the sonata reference 1). My phono stage is the ASR Mini Basis Exclusive. All or any suggestions would be greatly appreciated.
Thanks!
128x128goofyfoot
Pryso, thank you for the clarification!

BTW, I see nothing problematic with Goofyfoot's interest in an Ortofon SPU Mono (first post).

kind regards, jonathan
Thanks for the info Podeschi and thank you Jonathan for the recapitulation concerning the Ortofon SPU mono. The only hesitation I have about the Ortofon SPU however, is how well it is or isn't suited for my Thorens tonearm. The Grado cartridges seem attractive for the price as well but either way, I can then relax and begin saving for the Lyra Titan Mono and a new tonearm!
For anyone in the Dallas area, the LSAF is this weekend and I'll have a shilabe and a premium Be mounted up for some fun stereo vs. mono comparisons in a zero pressure tequilla fueled cinco de mayo environment. (will be there on siete de mayo too)

Local folks should at least be aware that a bunch of audio geeks are getting together even if they aren't vinyl junkies.

anyone silly enough to make a last minute road trip should understand the rest of the system will be about tubes, nickel and tone which is a perfect environment to transport you back to a smokey room in 1956.

dave

dave
It's interesting to note that some but clearly not all MC cartridges emphasize using a step up transformer. I in ways view using the transformers as something necessary in the past however not so much with today's cartridges. Anyway, this is a consideration when deciding which mono cartridge might be the best; should I spend money on a cartridge and a transformer too?
Goofy, MC cartridges are typically classified as "High Output" (HO) or "Low Output" (LO). LO is loosely defined as something less than 1.0mV at 5cm/sec. (This is not written in stone.) Most of the mono MCs under discussion here have an output somewhere between 0.3 and 0.8mV. If your phono stage has enough gain for a stereo cartridge with such an output voltage, then it will also work with a mono cartridge of that ilk. You need to find out what is the gain afforded via your phono stage in order to decide whether you need a step-up transformer (SUT). If the use of a SUT can be avoided, so much the better for both your wallet and your results. On the other hand, some would say that the net result of using a SUT with a phono stage of modest gain capability is to be preferred vs using a hi-gain phono stage that may not otherwise sound as good. There is endless debate on this subject; I have no dog in that fight. You don't HAVE to use a SUT if you don't need it. This is basic stuff.