How are you playing your precious MONO Vinyl?

I have a dual tonearm, dual cartridge setup for stereo/mono playback. Stereo cartridge is a Lyra Atlas Lambda SL and the mono is a Lyra Atlas Lambda Mono, so essentially stereo and mono versions of the exact same cartridge. Both are mounted on identical tonearms (Clearaudio 12" Universal), and I use a dual phono input Boulder 1108  phono-stage.

This allows me to make a rather equivalent comparison. Playing a mono record using the stereo cartridge and phono-stage mono button engaged sounds great. However, it’s nothing like playing using the dedicated mono cartridge. The latter has a lower noise floor, is more dynamic, more detail, and has vastly improved realism and dimensionality.

[this based on info from the Altas Mono manual]
On mono records, the vertical axis of the groove contains no musical information, but it will frequently have noise, in the form of groove damage and dirt. A true mono cartridge is completely insensitive to the axis, which greatly improves the signal/noise ratio. This is one of the largest benefits to using a mono cartridge and why it sounds so much better than using a stereo cartridge with the mono button engaged on the preamp/phono-stage.

it’s good to know that a standard phono stage with proper mono summing might get you 90% there

I wouldn’t say that is so. The difference using a true mono cartridge is a lot more substantial. Offhand, I would say using mono summing at the phono-stage or preamp with a stereo cartridge gets you more like 70% there, at the most. At least that’s how I would compare the difference in my setup, where I can try it both ways with nearly identical setups for each.

If you’re using a stereo cartridge, I don’t see how a mono phono-stage would matter, versus summing the mono with a switch on a stereo phono-stage (or at the preamp). The real difference for mono playback is in the mono cartridge itself.

I guess it’s something you have to experience before it sinks in. It’s pretty amazing how much better a true mono cartridge can be, especially with well recorded/mastered albums (like some of the Tone Poet reissues).
 

@lewm 

The Lyra mono cartridges (Kleos, Etna, Atlas) are true mono cartridges. They are not strapped versions of the stereo cartridges. Dynavector also makes a true mono version of the XV-1s. 

For about $300 one can dip their toes into using a true mono (not strapped) cartridge with the Audio-Technica AT33MONO.

@lewm 

I think the stereo/mono equivalence for a comparison between my two cartridges is quite valid. They are both Lyra Atlas, i.e. the same design. It’s just that one has stereo coils and the other has mono coils, and if you look at the design diagram on the box of each they are exactly the same. Only the coils differ between them. Otherwise they are the same cartridge (i.e. design and build). I can only tell the difference between them visually by looking at the serial number.

With the Lyra Mono one can also connect the two mono channels in series for additional output when used in a pure mono system.

See here what Lyra (i.e. @jcarr) has to say about it: https://lyraanalog.com/atlas.php (you’ll need to select the Mono link on that page)

@elliottbnewcombjr 

 

• True Mono vs. Stereo Cartridges:

  It's important to note that a "true mono" cartridge has only two pins, while a stereo cartridge has four. Using a stereo cartridge on a mono LP can cause damage to the record. 

That's not always true. My Lyra has four pins but it's a true mono. See my earlier posts. Here's what Lyra says about it:

Two totally separate monaural coils are used in the Atlas Mono, since most monaural cartridges are used with stereo amplifiers and stereo speakers. The separate coils also help avoid possible ground loops and hum problems that could otherwise be caused if a single coil is fed into a stereo two-channel amplification system, thereby tying the two channels together electrically.

In addition to parallel mono connection to a stereo system (two amplifiers and two speakers), it is also possible to leave one set of connections unattached for pure mono playback with a single amplifier and a single speaker. However, it is also possible to connect the two mono channels in series for additional output when used in a pure mono system

I believe most records from 1955 on use RIAA. My phono-stage has additional equalization settings for EMI, Columbia and FFRR (Decca) but I don't have any records (mono or otherwise) that were mastered with those curves. The 1950s OGs I have already use RIAA.

Before I had a mono cartridge, I definitely heard improvement engaging the mono switch on my preamp when playing mono records with my stereo cartridge. It mostly came in the form of noise reduction, but it didn't benefit in other ways like the true mono cartridge does. I never engage the mono switch when playing the mono cartridge since that's pointless to do. Even Boulder in their manual says the mono switch is for playing mono records with stereo cartridges.

@elliottbnewcombjr 

Note that you really only need a mono switch for LPs made before 1968 or so. Mono records made after that are cut with a stereo lathe.

That’s correct but not 100% correct. When mono records are cut with a stereo lathe, the cutting head is reconfigured for cutting mono. It’s not quite the same thing as cutting stereo. Kevin Gray has explained that in one of his interviews or white papers (I can’t remember which).

Use a mono switch for mono records cut since the mid-60s too. It can improve the sound and reduce noise.