One More Time: "True Mono" Carts vs. Mono Buttons/Y-Cables

About a year ago I got into mono vinyl, and I did some A-B testing on entry-level "mono" carts and some stereo carts utilized with the mono button on my amp:

Shure M44-7 and M44G (stereo .7 mil conical)
Grado MC+ ("mono" .7 mil conical; not a "true mono" cart I guess but wired different internally than the effect of a mono button or Y-cable to produce less noise...in theory)
Ortofon D25M (stereo 1 mil conical)
Shure M97xE (stereo elliptical)
Audio Technica AT440MLa (stereo elliptical)

To my ears, the differences between these carts regarding signal-to-noise ratio and inner groove distortion (not frequency response), with mono records and the mono button on my amp pressed, were extremely minimal. However, I understand that none of these are "true mono" carts, as with a true mono cart (correct me if I'm wrong) there is a single coil inside the cartridge which ignores the vertical movement of the stylus (opposed to the dual coils in stereo carts). I also understand that vintage mono carts have minimal vertical compliance while all modern carts have vertical compliance to handle stereo grooves. But the important thing seems to be the coils inside the cartridge when it comes to noise...is this all sounding right? (I also understand that pressing the mono button on an amp or using a Y-cable dramatically reduces noise when using a stereo cartridge with mono records.)

So in theory, with one of these "true mono" carts (Denon DL-102, Miyajima Spirit, Dynavector DRT XV-1s) do you actually get even less noise than pressing the mono button on an amp, and if so, does it have to do with there being less vertical compliance, the coils, a combination of both? I'm not really concerned with whether or not the difference is "substantial" or audible at this point, just the theoretical aspect of it. I'll leave all that to my ears later when I have enough money to do my own A-B testing.

 

I'm surprised you haven't gotten a response yet. I'm not an expert and may be talking out of my rear but the difference is that a mono cartridge will only track the side to side movement and will ignore the up and down.

 

Yes, which is why all but a small handful of them are not recommended for playing any post 1968 mono or mono reissues cut with Stereo cutting heads.

 

It seems that during the period 1958-1968 there was a gradual conversion from Mono to Stereo cutting heads for Mono records. I've gotten pretty good [I think] at detecting when my 1mil conical stylus is riding in a narrower groove cut with a stereo cutting head. I find that up until about 1964 I can safely use my 1mil stylus for optimal playback. After '64 it's hit or miss. When my 1mil stylus hits a groove cut with a Mono cutting head everything sounds balanced and "right", a perfect fit if you will. But if I play later Monos with the 1mil stylus I can detect a specific type of distortion that immediately tells me the groove was cut with a Stereo cutter. And I find this with quite a few Mono LPs after 1964 and I've even noticed this as early as 1962.

 

Although it makes sense to me that a mono stylus should not be used on a mono record cut by a stereo cutterhead, I've been told by a mastering engineer that it shouldn't be a problem since the groove would be identical to one cut by a mono-cutterhead, because there would still be only 1 channel of sound being cut, thus only lateral movement.
This too makes sense, so I'm not sure what to think, as it directly contradicts the other train of thought.

I think it's important to distinguish between mono records cut on stereo cutterheads, and mono records cut from stereo TAPEheads - using a mono cart on these would be a huge no-no, since there would be vertical modulation in the groove, however slight. Damage is a probable worst case scenario. Sound would also suffer cyclic phase cancellation in a best case scenario.

I've also heard from the same engineer that it's standard practice to cut mono from stereo tapeheads these days, so take that as you may. I would have thought that more high end mastering facilities would be equipped with the proper full-track head to do the job, but what do I know.

 

True but the size of the groove cut by a stereo cutter head is smaller. So a larger mono stylus is not going to trace the groove as well as a smaller stylus of comparable size to the stereo cutter head. You've got the top portion of the stylus extending out of and above the grooves. I have read that this shouldn't really make a difference but I find that it does. Later monos sound better with a .07 mil conical than with a 1mil.

 

Plus, you also have the vertical compliance issue which many mono carts are not safe for. Which is also a strong reason why my mono playback is generally with .7 mil broadcast conical styli capable of doing both.

 

Thanks for the input Bubbamike, though that doesn't quite answer my question. As far as I know, some modern "mono" carts not only have vertical compliance but they also have coils similar to comparable stereo models made by the same company, but I guess the coils are wired differently than in the stereo cart so the vertical signal is "cancelled". My question is basically, with carts like these, is that canceling of the vertical signal somehow less effective than have a "true single-coil" mono design, i.e. is there less noise with a "true" mono cart...? Please note that I realize that my terminology might not be quite right, as I understand that this is an intricate technical issue I'm curious about

 

I think that the difference between a true mono cart and flipping a mono switch is pretty subtle, and money might be better spent elsewhere. In my own situation, I had two tables, and both mono and stereo LPs, so I figured why not have a dedicated mono setup. I went with a DL-102, which is true mono, .7, has verticle compliance, good reviews, and is reasonably priced. That way, I don't have to stop and think about what year or lathe was used on an LP. Heck, I have at least one album marked mono on the label that has stereo tracks on it, so am never comfortable on issues like that. I have read that it was originally made for Japanese AM stations so they could play stereo LPs. Anyway, no switches to throw, no cartridge swaps, no studying record lables, no wondering if a mono cart would sound better or have less noise.

 

so is bridging the channels the preferred method for stereo cut mono played back with a stereo cart?

 

For the vintage mono records of mine which I used for my A-B testing, I could not really hear any difference between the 1-mil Ortofon D25 and the other .7-mil stereo carts (with the mono button pushed in on my amp), and I'd say I'm a fairly experienced listener who compared these carts excruciatingly. I have recorded the comparisons, and I may release them on a blog at some point, but to each his or her own.

Additionally, from what I understand, not only will a .7-mil stylus will ride the groove of a vintage mono record just as well as a 1-mil but it will "sit" further down in the groove, avoiding the potentially damaged top edges of the groove wall while reaching a previously untouched part of the groove (it makes sense that it's more important that the record is cleaned in this case since a .7-mil stylus is more likely to touch dirt or gunk at the bottom of the groove). This is all in theory, of course. My real-world experience is that I really didn't hear much of a difference overall, though there were differences from time to time. If I'm oversimplifying, please feel free to correct me people.

What kind of 1-mil stylus do you have?

 

Let's be clear that the important trait of a "true" mono stylus here is that it has minimal vertical compliance (as far as I understand).

I hear what you're saying about there not being "stereo fluctuations" in the groove with a mono record cut with a stereo head so there shouldn't be a problem, but as far as I know, the shape and width of the groove is different, so I'm assuming that causes problems. But sure, the amount of vertical variation (error) in the groove of a mono record cut with a stereo head shouldn't be any greater than with a mono record cut by a mono head...right??

At first I didn't understand what you meant by stereo tapehead, but then I was like "OHHHHHH". Modern mastering engineers are using two-track mastering reel-to-reels to play back full-track mono tape, is that right?? (I feel like I read this in a older post and I never knew that was possible.) So that causes phase problems when the channels are summed with a "faux-mono" cart, a mono button on an amp or a Y-cable since subtle vertical modulations are created in the groove??

 

Ortofon Concorde from KAB. When I play older mono LPs with a .07mil conical they sound good but the overall image is thinner. With the 1mil the sound is fuller, beefier with less surface noise. This holds true with beat up LPs as well. I'm assuming this is because the larger stylus is reading more of the groove walls.

From KAB's website;

Cartridge features 1.1mil ProS stylus ideal for mono microgroove. Do not be lured by mono cartridges alone. The cartridge should be stereo. Our better preamps let you mix the 2 groovewalls for best overall fidelity. You cannot do that once you commit to a mono cartridge!

The 1 mil tip is larger than the standard 0.7 stereo tip and in many cases will trace a fresh unworn path producing cleaner transients and dynamics.

 

I think what's being suggested here is that lack of vertical compliance is not an issue if a mono record cut with a stereo head is made from a full-track tape machine--the problem is the groove shape and size. Though it seems a lack of vertical compliance can be a (slight?) problem with a mono record cut with a stereo head made from a two-track tape machine...honestly I still can't see the lack of vertical compliance being a huge issue even in this case, though it makes sense that a vintage mono cart could straight up damage a stereo record with all kinds of crazy vertical modulations in the groove.

 

Yes, either that or using a modern mono cart with a .7-mil stylus. Surface noise will be dramatically reduced by phase cancellation and "masking" of the music.

 

The direct link to the page doesn't work. Start here;

http://www.kabusa.com/frameset.htm?/

Click "phono cartridges". On the left side click "Ortofon Hi Fi". 2/3 the way down the page on right "KAB/Ortofon ProS".

 

There always seems to be these back-and-forth debates on mono/stereo playback and which cartridge to use. Unless you're playing lots of pre-1960 mono records, a 0.7 stylus tip should be okay, right? And as long as it has some vertical compliance for mono-cut-by-stereo heads, it should play those fine, right?

 

Yes. I play a lot of mono LPs so I'm more picky.

 

My understanding is that a mono cartridge that does not pick up a vertical signal (and thus does not need to be summed) will essentially produce the same signal as a summed stereo cartridge, so I'm not quite sure what they're talking about here.

It would only be a "fresh unworn path" if the record had only been played with .7-mil styli, right? But how likely is that?? What are the chances a vintage mono record never got played at all around the time it was made but then got extensive play in modern times with a.7-mil stylus?? I think it's the other way around, actually, so I must be missing something. My understanding is that a lot of vintage 1-mil setups did damage to records if anything because people didn't replace their styli in a timely manner and tracking forces were extremely high. So a .7-mil will "avoid" all that damage caused by those old 1-mil setups, while a 1-mil stylus will just reiterate that damage...idk. I apologize if it sounds like I'm just defending my preference, I really just want to understand the theory behind this stuff, it's very interesting to me. But the bottom line, of course, is hearing the difference

I wish I could hear what you're describing. If there's less surface noise, that's understandable. I did not find that to be the case.

I can imagine that a wider conical stylus could sound better than a narrower elliptical stylus with records in poor condition because in that case the larger conical is "swooping" over the damage and not picking up all the intricacies of the imperfections in the groove. I like to use a Shure M44G on old 45s and records in poor condition.

This doesn't quite make sense to me. My understanding is that it's all about the stylus reading the lateral "message" of the groove as accurately as possible, whatever it takes. Does a stylus that touches more of the groove's wall read the groove more accurately? Maybe...I'd like to see if anyone else has anything to say about this...??

But when you say that the sound is "fuller" or "beefier", you say it's in contrast to a narrower stylus sounding "thinner", which suggests to me that the sound of a 1-mil stylus is somehow "wider", which doesn't sit well with me. A mono signal is a mono signal, just one straight line dead center, regardless of stylus width. But if you mean something else by "fuller" and "beefier" I'd like to know...maybe it has to do with a more present midrange? Again, my experience with a wider stylus was that there was no "noticeable" difference in frequency response.

 

Indeed, there is always this back-and-forth debate. I personally am not looking to argue that a certain configuration is better here, I just want to understand the differences in the respective sciences of vintage and modern mono carts (ok maybe I'm getting a bit off-track and trying to justify my own personal preferences a bit ). My feeling is that a .7 tip is fine in any case, and I'm not going off theory, I'm going off experience. In general, my understanding is that any modern cart will play any microgroove record fine, stereo or mono, vintage or modern.

 

Anyway, my original question was really about the differences in the coils and the wiring inside all kind of mono cartridges. Can anybody chime in on this?

 

It's sort of like the difference between an mp3 and a CD. I don't know how else to describe it.

 

I wouldn't mind hearing those needle drops if you get a chance to upload them.

I agree with you that a narrower stylus sitting lower in the groove will more often than not mean quieter playing records. Because most damage to a record is superficial. This is why in my experience an MC cartridge with a line contact stylus will pick up less surface noise and tics than an elliptical.

 

I thought a line contact stylus is only narrower than an elliptical in terms of depth, opposed to width, am I wrong? In that case, it wouldn't be getting deeper into the groove, per se, though it would be hugging the tighter higher frequency turns more faithfully...?