How are you playing your precious MONO Vinyl?

Pertinent topic for me.

I use2 TT: a Linn LP12 for stereo, and Technics SP15 for mono.  I have 2 dedicated mono cartridges, and I will send a Fairchild 225a to a rebuilder for restoration.  My current mono cartridges are a Ortofon CG25 DI MKIII- this is a current version of Ortofon's original mono MC cartridge introduced in the late 40's,  The other cartridge is a VAS modified Denon 103- one set of coils is removed, and the other set is reoriented for horizontal content.  Both cartridges sound a lot different than an adapted stereo cartridge, or pressing the mono button.   The Denon sounds better to my ears and in my system.  It provides an extremely solid mono image with all of the improvements noted for mono cartridges, along with the extended frequency response of a current cartridge.  Solo instruments and small ensembles sound shockingly real and "in the room".  It is uncanny to listen to a 70yr old LP that has a silent background and music explodes from the grooves !

Others have noted that most "mono" cartridges are in fact stereo cartridges internally bridged to sum L/R channels to create mono output.  These cartridges STILL respond to vertical groove content.  A true mono LP does  NOT have any vertical content, all signal is cut in the horizontal plane IE side to side.  What is left in the vertical plane is noise, dirt etc.   A stereo adapted cartridge still reads vertical content, and still includes vertical content in what is summed to create mono output.  Some believe that the presence of vertical content that is then summed introduces distortion and phase anomalies that are audible.  A TRUE mono cartridge (single coil plane) only responds to horizontal content, and does not reproduce any vertical content- it is immune to the distortion and phase anomalies mentioned earlier.  Most listeners note a shocking difference when hearing a true mono cartridge for the first time.   

Mono LPs pressed from 1948 until the early-mid 60's have a groove width of 1mil.  Mono LPs pressed after the mid 60's and including current mono reissue LPs have a groove width of .07mil...a smaller groove width.   True mono cartridges from the golden age have 1mil conical stylus profiles, and some believe this larger stylus can damage an LP cut with a modern/smaller groove width.   For this reason, many believe that the best compromise is to use a single coil true mono cartridge, with a modern .07mil stylus.  Opinion is about equally divided regarding stylus shape, with many supporting conical shapes, and just as many preferring more exotic shapes (elliptical, hyper-elliptical, shibatta etc).

Regarding cartridges, phono stages and preamps, it seems that the most preferred and best sounding true mono cartridges are moving coil, that require additional amplification of signal.  Some use SUT / step up transformers, some use head amps/active phono stages etc.   In my experience the choice of preamp is not as important as making sure you have a true mono cartridge.  What is important is to be sure that your preamp has adjustable cartridge loading.   

Phono EQ is another contentious issue.  Some believe that non RIAA EQ coexisted until the early 60s and many report a more satisfying listening experience when playing an LP from the 50's and using a NON RIAA playback curve.  So it may be beneficial to consider a preamp that includes adjustable EQ playback curves.  There are several preamps that include selectable EQ along with cartridge loading.  

The OP probably did not realize there was so much to consider regarding mono cartridges and mono LP playback !

Good Luck.

If anyone is mono curious, I have a turnkey mono phono front end for sell on the ‘ ‘other site’… Miyajima Zero, Miyajima mono ETR SUT, Tektron mono phono (single Tele 12AU7 and 12AX7, and a single Cardas Clear Beyond phono cable (between the SUT and mono phono.

iopscrl

thanks for sharing your extensive knowledge.

I think your Technics SP-15 is a great TT. Many years ago, Wayne, my friend at Harveys, 45th st, nyc called me whenever something great was coming out of trade-in/repair to their used shelf. (my office was on 44th st, 1 long and 1 short block away)

I bought an SP-15, with a Grace Arm and Grace Cartridge. I gave it to my good friend, and recently installed the B500 arm base on it, and we got a replaceable stylus from Soundsmith for the Grace Cartridge. Changing headshells and/or armwands, tool free arm height adjustment, it is a great way to have alternates in a compact setup, WITH a dust cover, one of my pet peeves.

He ended up with this

What is your SP-15 in?

There are some mono cartridges that will destroy a stereo record. Which ones I don’t know. Which mono cartridges are not strapped but true mono cartridges; the mono cartridges that house two separate mono coils or a single mono coil cartridge. The stylus is a factor where it pertains to the groove width. Those new remastered mono repressings are cut with the same groove as stereo records. But what I find perplexing about the original post is the idea of using a mono cartridge and a mono phono stage. So would you use two different mono phono stages ( left & right) with a stereo cartridge? That could possibly prove advantages, just like using two separate mono blocks as your power amps. But as was mentioned previously, with a mono cartridge, the signal is equally mono in both channels before it reaches the phono amp. So I would just focus on getting the best phono amp possible. The ASR Basis is my recommendation. 

”what I find perplexing about the original post is the idea of using a mono cartridge and a mono phono stage. So would you use two different mono phono stages ( left & right) with a stereo cartridge? ”

@goofyfoot 

My original post is about a true mono playback. Two arms in the works, one for true mono cart and 2nd one for a stereo cart with dedicated phono’s. 

A true Mono cartridge has only one coil (or two coils wired in parallel) and outputs the same signal from both channels. You can use any normal stereo phono stage and you’ll just get identical signals in both left and right channels.

As far as ‘mono switch” on a preamp or phono stage, I don’t have any direct experience. Can it be further use to collapse any remaining noise artifacts, or completely redundant with a truly mono cartridge, we will see! 

The EQ-100 is designed with a monaural configuration with a L/R output for easier connection to a stereo system. The output signal from EQ-100 remains true mono or monaural. I am hoping to compare EQ100 in my system to see if mono vinyl sounds better with a purpose built phono, 

➡️ True mono cart + EQ 100 

➡️ True mono cart + AD60 (phono board in my Integrated).