Playing mono records properly without breaking the bank - a phono pre-amp question.


Hi there.. I can use some suggestions for playing mono records properly.I'm about to put together my vinyl system and trying to figure out how to best play mono records without having to either buy a separate TT, have a turntable with two tone arms or have a switchable head-shell, all of which are not an option at the moment.  Someday, I think having two tone arms will be the way, but now I need the most economical way to have a nice experience.
I will have at a minimum, a nice stereo stylus/cartridge, but I'm wondering if I should be focusing my phono-preamp search to those with a dedicated mono switch?  I have a Hegel integrated and there's no mono option. 
Are there  simple ways (contraptions)  other than a phono-preamp with a mono switch, to achieve high quality mono playback with a stereo stylus? My search for the right phono preamp would be much easier if I knew I didn't need to make sure it had mono.

Appreciate any suggestion or direction - would love to hear your person experience playing mono on a generally "stereo" rig.

hrabieh
Excellent stuff Elliot.
Mirrors my experience and possibly surpasses it.
Enjoy!
Mono LP's, Jazz, on my new Grado ME+ Mono cartridge ($150.)

I am VERY GLAD I got this.

Last night I played a collection of Jazz tunes, Chicago South Side Jazz, from 1927-1930.

https://www.discogs.com/Various-Chicago-South-Side-Jazz-Vol-1/release/5104002

Stereo cartridge, preamp in Mono, listening was more like a history lesson. One prominent instrument, everything else low volume, seemed a half mile away.

Very early Louis Armstrong, Earl Hines. I strained to hear them with Stereo Cartridge,

Repeated with Mono Cartridge, bingo, I became INVOLVED with the music, a huge difference! There, a band all together, there's Louis, there's Earl.

I thought perhaps a bit better, and am happy to report, ditch your reservations, get a Mono cartridge, it's a LOT BETTER.

I went for Elliptical at reasonable price, it's the mono wiring that makes the difference. IF I was more involved with Mono LP's I would probably spend more for a Shibata tip, the extra life of the stylus's with greater groove contact makes the increase in price somewhat meaningless if you take the long view.
You are a funny guy Mijo.
Hey maybe take a look at my system some time......
And read my posts where I clearly state I bought a 78 stylus to play , well that's right you guessed it 78,s!
My concern on playing mono records of older origin, so pre 1960,s would not be sound quality or anything along those lines but possible damage to the stylus of any of the carts I tried it with.
I do NOT consider a cheaper mono only cart like the 2m mono or grado me+ to be a huge expense or hassle.

My 2m is now mounted on a headshell and it is minutes work to swap it out on my Garrard and rebalance it and be playing with no worries.

Exactly the scenario I envisaged right from the start and it has worked out to perfection for my needs.
Uberwaltz, who stands to gain from you buying a cartridge, Ortofon and Grado or me. For as many Mono records as most people have it is not worth the money or hassle to have a separate system for playing them. Oh but I forgot. You are concerned about the Imaging. My mistake. 
Hrabieh, try playing the records. I have several new mono records, new pressings of old material and they sound just fine using any stereo cartridge I own. If you have old mono records you might want to clean them before you try playing them. If they play fine, end of story. If they sound noisy then a larger stylus might help, might not. 
I assume they are not 78s. 78's do need a larger stylus.
Uberwaltz, you need to switch to digital. This vinyl sh-t is going to drive you crazy.
I asked for this as a Christmas Gift from my Neice

https://www.ebay.com/itm/Abbey-Lincoln-Straight-Ahead-Jazz-Man-JAZ-5043-SEALED-REISSUE-LP-NEW-OLD-STOCK/382864848599?hash=item592485f6d7:g:wNYAAOSwqxRa398Q

Played it using AT440ML Microline Stylus is great shape sounding fab on Stereo LP's.

McIntosh Mode switch in Mono.

There was no solid center image. Unfocused random low level sounds from left, right, off center.

It's second play will be with my Grado ME+ cartridge that is in transit. I will report back!


Ah forgot, Mijo knows more than Ortofon and Grado et al.

Thanks for the informative post!
Just play the darn record! Forget about all that garbage about needing a special set up for Mono records. Just another way to get your money.
uberwaltz

this, from that ortofon article is what convinced me to get a dedicated mono cartridge.

"Another significant advantage of using a mono cartridge to play mono records is the absence of response to vertical movement. This means that a mono cartridge is essentially impervious to the pinching effect which comes into action when the stylus is pushed vertically upward in very narrow grooves. In addition, the response to dust, dirt and wear will be reduced substantially as the vertical component will not be heard. The final result will be a much more clean and noiseless reproduction of the mono record. These effects simply cannot be achieved merely by the use of a mono switch."

paying more attention since reading that, I realize there is definitely room for improvement even when using my McIntosh Mono Mode.

I picked the Grado ME+

https://gradolabs.com/cartridges/prestige-series-specialty-cartridges/item/79-mono-phono

High Output, Elliptical, their description of their innards is convincing. And the price beats Ortofon Shibata Stylus.

I'll know in about a week when it all comes together.
uberwaltz, if you are not aware, the Denon 102 has extra long connector pins so that two wires can be attached to each one. A Y adaptor is not needed. And the same (mono) signal will be sent through each stereo channel. Guess you could call that dual-mono.

Or you could connect it to only a single channel in your system.
A Shibata stylus works very well on mono records.  I use one, and a Counterpoint SA-1000 with no mono switch, and I get great, focused mono.  I did not get this with an earlier MM/eliptical setup.
I don't know if this has been covered already but the best way I found to play mono without a mono cartridge or mono switch is to add a double Y-adapter to the tape loop on your preamp if it has one. Simply press tape when playing mono LPs.
Uber, The 2-pin Denon is no problem, if you are content with driving only one of the two stereo channels, without a Y-adapter.  If you used a Y-adapter (so as to be able to drive two channels in mono), there are possible issues with impedance, but the question is equipment-specific.  You could try it.  I'd go with the AT33MONO, if it were my choice.
The mono switch solution allows you (or anyone) to compare the very same stereo cartridge used in either stereo or mono mode on the very same mono LP.  That way, there is no issue with the inherent quality of the cartridge, as opposed to the situation where you compare stereo cartridge A to mono cartridge B.  There you are doing more than just comparing stereo to mono; you obviously have the confounding factor of the SQ differences between one cartridge vs another.  But this must be at least the third time I've pointed this out.  So I'm done.

I have no experience with the Denon but have owned both the AT-MONO3/LP and the AT 33 Mono. 

While the AT-MONO 3 is a real bargain, it is a bit quirky in terms of its output at 1.2 mV, also with relatively high internal impedance. 

The AT 33 Mono, for not much more money (and only a couple of bucks more than the Denon) is an unbelievably good cartridge and not just for the money. 

It is admittedly a better match with my phono stage than the lesser 3/LP but the AT 33 Mono is really a great cartridge. 

Personally, I feel that a Mono cartridge is the way to go if you can, having experimented a bit with strapping stereo cartridges. 

I like my AT 33 Mono (on an inferior tonearm but on the same table and using the same phono stage with gain adjusted for output) much better playing both vintage and reissue Mono than playing them with my retipped stereo Accuphase AC2. 
Lewm
I was considering a Japan market Denon dl102 as a cheapish mono cartridge, plenty on ebay right now.
This is a 2 pin cartridge so a y adapter would be needed I assume.

Or if went with the also Japan market AT-MONO3/LP this has the usual 4 pins so must be bridged for mono internal in the cartridge. In this instance nothing else would be needed.

Ye it causes the head to spin!
This thread has become a dog's breakfast of conflicting and/or redundant suggestions.  (I just wanted the chance to use the "dog's breakfast" metaphor.)  Anyway, get something with a mono switch to start with, and then decide for yourself if you like listening to mono LPs in mono mode, or not.  I predict you will prefer it.  By the way, a mono mode selector switch is typically in the linestage or high level circuitry, so stand alone phono stages will not usually have such a switch, but there are exceptions to every rule.


Uber, On the perfectionist level, you ask a good question.  The result of using a mono cartridge into a stereo LP begs a few more such questions.  For all intents and purposes, if the mono cartridge provides 4 pins, 2 each for a left and right channel, then the result should be similar to using a mono switch.  For a 2-pinout mono cartridge, you'd have to make an effort to deliver signal to both channels of a stereo input, like a Y-adapter.  If you use a Y-adapter, then each channel of the phono stage looks back at the output Z of the cartridge in parallel with the output Z of the other channel.  That could have a small effect on tonal balance. I'm getting a headache thinking about this.
My record collection is mono only so I'm not burdened with the need to switch between stereo and mono. hrebieh, if I were in your situation, I'd buy a second turntable (used and possibly vintage) as a dedicated mono table with a mono cartridge.
What would be the result of using a real Mono cartridge with a stereo phono pre?
In other words no mono switch on the phono.
assuming, but not said, the MODE which includes MONO, exists on many but not all McIntosh models.
McIntosh MODE Switch detailed in this manual of mx110z tube tuner/preamp

http://www.berners.ch/McIntosh/Downloads/MX110_own.pdf

tone and loudness circuits, filters described also
hrabieh, your 12/10 summary seems like a "sound" solution.  ;^)

Hope you then enjoy those mono treasures.  For the future, keep in mind the differences with older (pre mid-60s) mono releases.
Setting aside whether or not there is a technical advantage to a true mono cartridge over a stereo one the real point here is that if you are going to the trouble of creating a second dedicated mono setup then this is a real chance to choose the flavour of cartridge that best fits with mono recordings. Maybe you prefer the sound of 50s mono played back through a cutting edge MC -- if so great. But for me listening to the Chordettes through my Zero despite it's ridiculous tracking force (3.5g) and far from svelte body has a magic, a fullness, tone and amazing sense of depth that somehow is missing on my far more expensive stereo rig.

And yes the same recording owned in both mono and stereo mixes is often preferable in the mono. Generally 50s and early 60s cutting setups delivered better frequency range (more HF) in mono than stereo (per my conversations on this topic with Tim de Paravicini) so that may be part of the reason. Anyway there's so much to offer and find in mono -- a mono switch is absolutely a good place to start (and helpful for hum cancelling even if you get a mono cart -- that's another topic) but don't give up on the dedicated mono search too soon.
I might disagree here.  Going mono does a lot to cancel out scratches and pops.
Just use a good stereo cartridge with good channel separation. 

Lots of garbage being spewed out trying to sound knowledgeable or scientific. 

You dont need to disable the stereo cart. The ever-so-slight differences in channels will be cancelled or helps to add depth to the playback. Disabling causes a very lifeless, dead, flat quality to playback. Save yourself the trouble and expense.
Thanks everyone for chiming in. Personal experience is always helpful from others specially at different price points. What I'm gathering from the comments are:

a) best to have the "mono switch" within the phono preamp to minimize any added signal loss and/or distortion.  I'm planning on getting a used phono stage so the KAB mono at $200 feels money best spent on a phono with mono switch. And don't see any KAB mono in the used market.  Thanks elliottbnewcombjr  for the suggestion.

b)Stereo cart may sound as good /better than a Mono cart, but as anything in this hobby feels like it depends on the implementation of the product, cost difference, etc. The example of the  $1k mono cart having more soul than a higher priced stereo cart certainly shows that there is room for experimentation once/if one goes deeper into this hobby.

c)Not being able to have a mono cart, separate rig, separate tone-arm, but having a mono switch may buy some time before the upgrade-itis kicks in.
As a picky perfection seeking engineer, looking for the highest resolution and imaging in my current digital rig, I'm sensing that I won't sleep soundly without a mono switch on my future phono preamp.


Elliott, have you used the KAB mono switch? Looks like an interesting solution, although another device in the chain could result in some distortion.

Folkfreak and Lubachl, The better experiment, to work around Folkfreak's valid point that when comparing stereo cartridge A to mono cartridge B, you have to guess at the differences due solely to the basic goodness of the two cartridges, is to compare, for this example, your expensive MC cartridge in stereo mode to the very same cartridge with the mono switch engaged.  This is what I do all the time, and I cannot think of an example where I liked the stereo mode better than the mono mode, using a preamp with a mono switch to amplify the signal from a mono LP.  (Of course, I am only talking about "modern" mono LPs, not 78s, which are not LPs at all by definition, or late 1940s/early 50s oddball recordings.)
Audio-Technica VM610MONO Phono Cartridge Grado ME+ Mono Cartridge Ortofon 2M Mono Phono CartridgeParasound Zphono XRM3 good mono cartridges that won't break the bank and a phono preamp with a a stereo/mono switch
phono pre for $599.00 and 3 cartridges from $125.00 to $375.00
@folkfreak, yes that is what I concluded.  The more expensive MC stereo cartridge was giving me more information and dynamic bloom than the lesser MM mono cart.  However, I remain baffled that many of my RCA monos have a bigger sound and slightly higher volume (same amplifier setting) than their stereo siblings. That is what prompted my somewhat expensive foray into the world of mono playback set ups.

Bubble Levels for TT.

I have several, and I bought over a dozen recently to include with an amp stand I designed. They are not as accurate as you expect. I now check them with other levels, return the one(s) that are no good.

My Thorens TD124 had a built in level, I trusted it without ever checking it against another.

Thorens had a built in speed control (a magnetic force/shield, pretty cool if you ever looked inside). You definitely needed to adjust the speed control as it warmed up, every time. I never need to adjust other TT speeds.
OP writes:

"not planning on getting a turntable with interchangeable headshell and
(c) don’t see myself wanting to get a cartridge with a removable stylus where I would switch out the stylus each time I want to play a mono record..(d) will not be playing any 78’s on this turntable".

That is why I mentioned the already setup TT. It is fully adjustable, but no need to adjust anything (except level via it's adjustable feet) (perhaps OP might want to try a different cartridge later).

The low quantity of Mono records he describes do not warrant the advanced considerations he mentions.

The remote controlled stereo/mono switch can be tried, kept, returned, about the same price as a different cartridge, but no skills/work involved.

I do have Stereo/Mono circuit in my McIntosh mx110z tuner/preamp (wonderful tube phono eq) as I mentioned.

I never tried a Mono cartridge. That is a specific alternate. Perhaps I will buy one I can return, try it, see if it bests the Stereo Cartridge/McIntosh Mode switch, keep or return it.
@lubachl regarding your experience comparing playback on your existing stereo MC with a cheaper mono cart. I suspect a lot of what you are hearing is the differences in carts. 

In my setup I have a pretty expensive stereo cart (AS Palladian) and an much cheaper mono (Miyajima Zero). Arguably the Palladian is more detailed, more accurate etc but the Zero has an ineffable sense of wholeness and soul that really brings out the best in mono (especially on the wood armed Durand Talea I mount it on). 

Suffice it to say listening to Martzy on the Palladian is a bit of an exercise in analysis whereas with the Zero one relaxes in pleasure. I do have to say that going mono can be spendy once you start getting a taste for ERC pressings (never mind the originals) and the like.

All in all I’d recommend you keep up your search for the mono cartridge that sings for you!
Because I have a lot of mono records in mint condition I thought it would be worth the effort to do just what you are considering, which is to get a dedicated mono set up with mono cartridge and separate arm for my TT.  Having gone that route, I felt as though the sound quality through my rather expensive stereo rig sounded better on mono records than the mono set-up.

I cannot explain why given the explanations noted above, which seem scientifically plausible. It should be noted that I did not have a mono switch on my phono pre or on my preamplifier.  Perhaps that is why there may have been some sound degradation.  I suspect the other reason may be that the stereo cartridge on my stereo set up is rather expensive compared to the mono cartridge I purchased and thus has better all around resolution and micro dynamics.

Most of the mono cartridges I auditioned before buying were moving magnet monos.  My experience has been that the best low to medium output moving coil cartridges are significantly superior to moving magnet/iron designs and that is perhaps why the stereo set up outperformed the mono set up.

My advice having gone this route, is as others have said, play the monos with your stereo set up and enjoy their rather unique characteristics.

Somewhat off topic, there are some cases where I felt my mono RCA "shaded dog" pressings of classical music were sonically superior to the stereo versions.  Oddly, perhaps others can comment on this, the front to back depth (imaging) and dynamic punch were greater on the monos than on the identical stereo pressings making them more enjoyable to listen to than their stereo counterparts.
hrabieh, optimizing mono playback can become complex, but basic enjoyment doesn't need to be.  Yes, there can be considerations for when the record was issued, groove width, even EQ.  But I believe the first consideration is which mono records will you listen to?

There are multiple reissues now of older mono LPs.  Since mono cutter heads are no longer available (so far as I know) these are cut with stereo cutter heads.  This simplifies matters as a stereo cartridge stylus should be just fine.  A mono switch may still be beneficial, such as Elliott suggested, to reduce background noise.

However, if you intend to play original monos from the late '40s to early '60s, by which time initial mono releases ended, then there may be no simple playback solution if you are concerned about sonics.  A modern stereo cartridge can be used but will not be optimized for stylus size, pickup type (no vertical groove information, only noise).  Also multiple EQs were utilized by different labels (requiring selectable settings).  So the best answer there is a second cartridge and specialized phono stage, which you want to avoid, at least to begin with.
Elliott, Your experience is slightly different from mine.  I played all LPs, mono or stereo, with a stereo cartridge for the first ~35 years of my audiophilia.  And I agree with you partly, I never felt a crying need for a mono switch or a mono cartridge.  However, the recent interest in mono LPs and mono playback induced me to acquire preamplifiers with a mono switch (I have two systems) and also a mono cartridge.  Since then, using these devices, I have been impressed with the positives of playing mono LPs in mono mode (either by using a mono cartridge or by switching or both). There is less high frequency "hash", for sure, but also there is enhanced clarity and a closer approach to the live sound.  I wouldn't go without at least a preamplifier with a mono switch, these days.  For certain LPs produced in both stereo and mono during the transition phase from mono to stereo, I can even say I prefer the mono version. On the other hand, I wouldn't argue that a casual listener could not be happy in stereo.
I play a lot of Mono Jazz LP's from the late 40's early 50's.

Most cartridges will play Stereo and Mono well. For your described use, TT with Stereo cartridge is all you need. 

Last night I listened to mostly Mono Jazz LPs for 3 hrs with an audiophile friend. They all sounded quite involving (you will find, stereo or mono, it depends on the recording engineer's skills as much as the artists).

I moved my McIntosh MODE switch to Mono, back to Stereo, both sound very good, some might be slightly better in Mono mode, but Mono played by Stereo cartridge is still quite involving.

LP Stereo playback began in 1958. Some engineers anticipated that and recorded with two or more mics to be ready. Those masters can be re-engineered to Stereo successfully. Avoid 'mono reprocessed to stereo', they generally sound worse than the mono original.
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I do advise that you get a TT with the possibility of adjustments.

I use this fully adjustable TT  which fits your budget

https://www.amazon.com/Audio-Technica-AT-LP120XUSB-Direct-Drive-Hi-Fidelity-Anti-Skate/dp/B07N3S4X3P/ref=asc_df_B07N3S4X3P/?tag=hyprod-20&linkCode=df0&hvadid=312150547590&hvpos=1o2&hvnetw=g&hvrand=8381325411824345964&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9003512&hvtargid=pla-681677883325&psc=1&tag=&ref=&adgrpid=70581793108&hvpone=&hvptwo=&hvadid=312150547590&hvpos=1o2&hvnetw=g&hvrand=8381325411824345964&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9003512&hvtargid=pla-681677883325

The supplied cartridge is factory aligned, just level the TT and off you go. You may never change anything, but, then again, you might.

I changed the cartridge to this one (so I could lower the tracking weight). 

https://hifiheaven.net/shop/Shure-M97xE-Audiophile-Phono-Cartridge?language=en&currency=USD&gclid=Cj0KCQiA_rfvBRCPARIsANlV66MTfCEX1XGRPd6RY8AFCDxTaPR1TXzZgw3rNCawEV6Nlr320_5Wfw4aAs4iEALw_wcB
....................................

McIntosh MODE Switch has a MONO mode. (some, not all models).  

Stereo; Mono; Reverse Stereo; L or R hither and thither separately or together.

Mode Switch is a great help when balancing your system. Stereo Reverse is very revealing of any imbalance. My speakers have two rheostats for brilliance and Presence. They need to match each other, the Mode Dial is a big help with that. IF you change a cartridge, or check your existing one, Stereo Reverse is very helpful refining anti-skating for proper l/r groove tracking. L to R, ... all help get it right, I wouldn't live without it. 
What Lewm said in the last two sentences. The phenomena is just a little more pronounced if you have a true mono cartridge like Miyajima.
FWIW, if you are looking used for a phono preamp, I have a PS Audio GCPH that has a mono switch. It's a great preamp and very versatile with lots of loading options. I use a different preamp now, but kept the GCPH for a back up.
No, there is really no "good" external switch for this purpose, because the signal voltage from a cartridge, even a high output one, is very low compared to line level signals, and passing that signal through a switch will inevitably do harm.  Some similarly recommend a Y-adapter placed in the line from cartridge to phono input.  That's not a good idea, because of the impedance anomalies that will result.  (It's too complicated to explain here.)  However, it might "work" to place a Y-adapter in the line between the phono stage output and the linestage input, if you are using separates. Because impedances will also be affected in this topology, you'd have to experiment on a case by case basis (phono stage/linestage combos).


Depends upon the design and quality of the switch.
I don't understand the comment that the DV17D3 per se isn't good for mono compared to other modern stereo MC cartridges.  All modern stereo cartridges should be about the same in mono, for good or ill, and assuming a stylus shape that is "modern", i.e., line contact or modified elliptical type.  A stereo cartridge with a conical tip might do mono slightly better than the foregoing, but such a stylus shape is not very good for stereo in the first place.

Finally, you didn't ask this question, but I wanted to comment that having a mono switch on your preamplifier to my ears gives about the same (good) result as using a mono cartridge.  I have both, and that's my opinion.  This thread will go on and on, so I would also mention here that there are both "true" mono cartridges and mono cartridges that are made from stereo cartridges by bridging the channels internally.  In the latter case, that is more or less like using a mono switch.  Also, IMO, there is tremendous benefit to playing mono LPs in mono, no matter how you get it done.  On the other hand, most mono LPs also sound "good" in stereo mode, if you cannot afford the equipment needed to go mono. You'll just hear more noise due to dirt in the grooves and to recorded hf that amounts to noise and is cancelled out in mono mode.



Hi everyone, thanks for your feedback. I fully understand the benefit of having a mono cartridge. I don’t however want to go that route since only a small portion of my collection today and possibly into the future will be mono.. also (a)I’m not quire ready for a turntable with two tone arms and (b) not planning on getting a turntable with interchangeable headshell and
(c) don’t see myself wanting to get a cartridge with a removable stylus where I would switch out the stylus each time I want to play a mono record..(d) will not be playing any 78’s on this turntable.

therefore my options as I see it and based on your comments:


i)playing with everything stereo.. stylus and phono and no mono switch anywhere.ii)playing with stereo stylus with a phono that has a mono switchiii)playing with a stereo stylus with a phono that doesn’t have a mono switch but uses an external device to handle the mono.

So here are my specific questions and hope you can answer them
Q1) Is there a good external switch/box that can be placed between a phono preamp and and a preamp/integrated that allows me to purchase a phono preamp without a mono switch..

Q2) is there a sonic hit between a phono with a mono switch built in and an external one?
Q3) As a newbie, I’m feeling like $500 is my limit for a cartridge.. is there something I should be looking for in a cartridge that plays well both in stereo and mono.. meaning, if the reviews are positive comparatively for their stereo playback, is it a given that it will play well in Mono? yeti42 , according to your experience, the Dynavector 17D3 wasn’t all that good with Mono, which is why I’m asking this question. Wish I had the budget for one of those because I’m looking at the Well Tempered and they apparently favor Dynavector Carts.Thanks everyone.


I believe both AT and Ortofon have Plug n Play mono cartridges if your headshell is removable. If not, unless you really play mono quite a bit, I would just use a mono switch for such. 
If you go on over to SoundSmith.com and check out the info there, or search YouTube where you will find a lot of the same videos, you will find Lederman has some very good info on mono. Its not something I'm into, just love listening to guys who know what they're talking about which Lederman is pretty high up there. Some of what he says about mono is buried in with other subjects, so you may have to watch the Stereophile guy get a tour of SoundSmith for half an hour to catch the 30 seconds mono comment, but if its important to you it'll be worth it. Nobody else I've seen so clearly explains exactly what is going on when you play a record.
If you’re not into antique records (pre 50s or old 78rpm) then an MM cartridge with true mono signal generator like Grace F-14 MONO (just two pins for lead wires) and modern stylus profile (not old conical) - this is all you need for use with conventional phono stage, amps etc
Some mono records were made to be playable with  a stereo pickup but the earlier they are the less likely this will be the case and those that weren’t have a sound like frying eggs in the background, a mono switch (mine’s on the pre) will get rid of that and move any pops and ticks to the centre with the music (not always desirable). I tend to use mine just when necessary as there is a minor dulling of transients that come with it. Choice of stereo cartridge is also a factor, a 17D3 with its micro ridge stylus didn’t play mono that well.