True Mono from a Stereo cartridge - switchable !

[steve195527]

Hi Steve,

I get out plenty. I also get sarcasm. You probably don't want to get into a sarcasm match with me. My wife is constantly on me to curb it so I will be fit to be around civilized people.

I question if you get sarcasm or tolerate it well as you seemed to take offense at the amount I dumped on you.

Examples:

To your - Electronics Bad! I asked how you were connecting your phono cartridge to your speakers without the benefit of electronics.

To your - EQ Bad! I questioned if you knew what a phono stage is.

To your - Gain Bad! I pointed out that most of us realize that you need a fair bit of it to get from the level out of your cartridge to line level.

Now you may say that you didn't realize that my phono stage was a stand alone phono stage to be used instead of the stereo phono stage as opposed to in front of it. I did put up the schematic of it and a description. If you didn't understand what it is you could ask before coming up with statements like the Stanton engineers have forgotten more stuff than I am likely to ever know.

Your apology is accepted.

Phil

H Steve,


"Oh yes,don't use any EQ or even any gain! don't be so touchy and I still think Stanton will know,probably forgotten!, more about reproducing mono and stereo than you,just saying they advised a far simpler solution,how many records play mono vertically??"

A good many of us here are aware that most MM (and MI and variable reluctance) cartridges require ~30 dB of gain at 1 kHz to get to line level and equalization to complement the record EQ and convert the velocity response of the mag cartridge to an amplitude response.

All designs are a compromise to optimize the goals of the designer. If I were working for Stanton (or any other cartridge manufacturer) and my boss came to me and said I need a circuit which can be implemented on our existing products by our customers at little cost or effort there is little doubt that I would say just put the channels in parallel. Does it work? Fairly well. Is it optimum? Not really, for the reasons ld outlined.

ld put his coils in series to address the issues he stated in the parallel approach. He is not the first to do that or the only one. The person who provided a 3 mill stylus for my Sonus cartridge is a big proponent of the series connection.
Joe pointed out how the series connection will raise the output impedance of the cartridge and cause capacitive loading of the cables and preamp to be an issue. ld then pointed how he mitigated that issue.

Now my goals.

1. accurate summing of the channels for mono
2. ease of switching from lateral to vertical
3. load on each channel of cartridge the same as the stereo phono stage it was designed for
4. Choice of play back EQ
5. Easy switching from mono to existing stereo phono stage.
6. Ability to switch from left channel, right channel, or the sum when in mono

I think my design addressed all of the above goals.

Am I as smart as the Stanton Engineers? Who knows.

Am I a reasonably competent engineer? Well I hope so. I do have a BSEE and now have for the most part retired after a career of designing RF and analog circuits. I have been an audiophile for most of my life and have designed several amplifiers and preamps for my use.

Phil


[

Phil
If you can't tell that I was being sarcastic perhaps you need to get out more?sorry if I offended you,I din't mean to but seems you're going to take whatever I write the wrong way,no probs carry on fiddling with things

Decided its not worth effort

[Ldg]

Steve195527, for whatever reason it seems to me you set out to trash a perfectly good and interesting thread here, trolling and posting nonsense on a topic it turns out you're not even interested in.

There's no question that CP's preamp is of enduring interest, and that CP is skilled in the art and worth listening to.

JaS, if you feel inclined and have a few minutes, any chance of a tidy up please ?

[hi_torq]

Excellent post and very neat switching arrangement. But I have to ask: Why not parallel the coils? (I once used a Shure SC35 with coarse-groove tip to transcribe some 78s, with its outputs strapped together). Since both coils are operating in the same magnetic field, they would not be subject to the same mutual loading that would otherwise be the case.

I would be a little uneasy about having any extra set of contacts in that part of the chain.

In my case I can simply derive a mono feed on my vintage console, but I appreciate that not everyone has that facility.

On (old-school) professional audio equipment, with transformer-balanced outputs, it was quite acceptable to derive mono (or combine outputs of machines) by series-wiring their transformer secondaries.

[steve195527]

Steve195527, for whatever reason it seems to me you set out to trash a perfectly good and interesting thread here, trolling and posting nonsense on a topic it turns out you're not even interested in.

There's no question that CP's preamp is of enduring interest, and that CP is skilled in the art and worth listening to.

JaS, if you feel inclined and have a few minutes, any chance of a tidy up please ?

trolling in what way
I would have thought anybody who wanted to listen to any records,mono or stereo,would have already had a phono-stage(inc equalisation! albeit todays standard)so listening in mono only really takes the adjustments stanton advice to the terminals,that is why I originally asked why so complicated,is that nonsense? it is very easy and used to be the method used years ago,I must have imagined that it works?

[Ldg]

Excellent post and very neat switching arrangement. But I have to ask: Why not parallel the coils?

Thanks ! Parallel wiring's not bad, it's just not optimal. And doesn't sound or measure anything like as good/well as series wiring to me..... Because in parallel wiring, unless L&R channels have exactly identical signal, then one coil will load the other in an odd and undefined way. Consider the extreme case of pure L signal with zero R signal. With parallel wiring the R coil loads the L coil, in series wiring it doesn't. This is obviously relevent for stereo summed to mono, but is also relevent for true mono when non-ideals aren't identical.

In series wiring, the cartridge is always loaded properly and in a defined way. The output is always a simple voltage sum, not a shunted undefined.

Not only does this sound right playing true mono recordings to me, but the noise improvement on stereo summed to mono is useful for those stereo records where one is unlikely to find another copy, but surface noise is a distraction. Then the noise reduction and overall sound improvement can sometimes be worth losing the stereo image, IME.

I would be a little uneasy about having any extra set of contacts in that part of the chain.

I used a sub-min toggle switch under the armboard near the pivot, where the tonearm wiring terminates anyway. Nothing I'd attribute to contact noise, hum etc.

[Coffee Phil]

Steve,

Do you still not get it? You did not simply stop at asking for the rationale of the other approaches presented. Actually each poster gave the rational of his method but if you did not understand you could always ask. You instead implied the those of us who dared depart from what you are seeing as Stanton's edict are either stupid or blasphemous for violating the sacred Stanton Rule.

If you want to show that paralleling the outputs of the cartridge is the equivalent or even superior then go ahead and draw an equivalent circuit and using Kirchhoff's laws come up with the equations and prove it. Just don't be giving us this "The gods of Stanton say so, therefore you guys are stupid" crap.

Phil

Steve195527, for whatever reason it seems to me you set out to trash a perfectly good and interesting thread here, trolling and posting nonsense on a topic it turns out you're not even interested in.

There's no question that CP's preamp is of enduring interest, and that CP is skilled in the art and worth listening to.

JaS, if you feel inclined and have a few minutes, any chance of a tidy up please ?

trolling in what way
I would have thought anybody who wanted to listen to any records,mono or stereo,would have already had a phono-stage(inc equalisation! albeit todays standard)so listening in mono only really takes the adjustments stanton advice to the terminals,that is why I originally asked why so complicated,is that nonsense? it is very easy and used to be the method used years ago,I must have imagined that it works?

[steve195527]

[quote="Coffee Phil"]Steve,

Do you still not get it? You did not simply stop at asking for the rationale of the other approaches presented. Actually each poster gave the rational of his method but if you did not understand you could always ask. You instead implied the those of us who dared depart from what you are seeing as Stanton's edict are either stupid or blasphemous for violating the sacred Stanton Rule.

If you want to show that paralleling the outputs of the cartridge is the equivalent or even superior then go ahead and draw an equivalent circuit and using Kirchhoff's laws come up with the equations and prove it. Just don't be giving us this "The gods of Stanton say so, therefore you guys are stupid" crap.

Phil

there you go being touchy again,doubt you can find anywhere that I have said or even implied that?Simpler still is just a Mono-button,but some pre's don't have those do they,the signal quality on mono records isn't worth all the trouble IN MY OPINION

[Coffee Phil]

Well Steve, I think not many here would see much daylight between my version of what you said and this:

"Oh yes,don't use any EQ or even any gain! don't be so touchy and I still think Stanton will know,probably forgotten!, more about reproducing mon and stereo than you,just saying they advised a far simpler solution,how many records play mono vertically??"

other than I attempt to come closer to using correct punctuation and use complete non run-on sentences.

If you think optimising mono playback is "worth all the trouble" or not is up to you, however it is a sub-hobby of the audio and vinyl thing for some of us here.

Yes many preamps have a mono switch (my Hafler does not) but it is designed to work on all of the preamps functions therefore it is located after the phono stage. If the gain match and phase match in the channels is very good the vertical cancellation will be good. The insistence by the devotees of "real mono" cartridges that their mono switches with a stereo cartridges do not rival their mono cartridges is testomony to the notion that the mono switch is not always optimum.

Phil

Steve,

Do you still not get it? You did not simply stop at asking for the rationale of the other approaches presented. Actually each poster gave the rational of his method but if you did not understand you could always ask. You instead implied the those of us who dared depart from what you are seeing as Stanton's edict are either stupid or blasphemous for violating the sacred Stanton Rule.

If you want to show that paralleling the outputs of the cartridge is the equivalent or even superior then go ahead and draw an equivalent circuit and using Kirchhoff's laws come up with the equations and prove it. Just don't be giving us this "The gods of Stanton say so, therefore you guys are stupid" crap.

Phil

there you go being touchy again,doubt you can find anywhere that I have said or even implied that?Simpler still is just a Mono-button,but some pre's don't have those do they,the signal quality on mono records isn't worth all the trouble IN MY OPINION

[Ldg]

If you think optimising mono playback is "worth all the trouble" or not is up to you, however it is a sub-hobby of the audio and vinyl thing for some of us here.

I suspect relatively few realise how well recorded much of the mono stuff is, how good many performances are, and why it's worth the effort to optimise.

If nothing else, there are a lot of 'essential' mono recordings, much of the Beatles classic albums stuff for example. When listened to with bona fide mono playback, it is ultimately how those versions were monitored in production and intended to sound. And it is a different experience, and very very good.

For a large part of the 50s/60s, mono was the mass hifi media, producers seemed to think 'mono' first, and stereo was a new toy in pop at least, where the art had not emerged. For example, lots of hard pans, and weird instrument locations. Personally, I think this is illustrated well in Beatles material, where I find many mono versions simply artistically preferable, and where playback on bona fide equipment makes the whole sound intention fall into place.

That's without getting onto the merits of Decca's excellent FFRR recordings and masterings, many performances captured by which remain unsurpassed and definitive. What is one to do, play them sub-optimally or not at all ? Should be illegal

Although I acknowledge proper mono playback seems a bit 'minority interest', if one cares about sound and music i think it obviously warrants a place in one's vinyl system. And without it, any setup is definitely the poorer, as I see it. And there's no mistake, it can be true hifi by the classic definition.

[Ldg]

The insistence by the devotees of "real mono" cartridges that their mono switches with a stereo cartridges do not rival their mono cartridges is testomony to the notion that the mono switch is not always optimum.

Series wiring, or well devised voltage summing, marks a significant step forward, and toward convergent opinions.

Proper true mono carts have restricted vertical compliance. Whether this is a good or bad thing is debatable, but they are then bona fide. You then can't play stereo pressings on them, for obvious reasons ! If one does buy a true mono cart, this is a crux issue, not all implement this feature. I think the DL-102 is still in production, though I've not tried it, that has crossed my mind.

Personally, series wiring/proper voltage summing gets it done.

[Coffee Phil]

Hi ld,

What you said about mono cartridges is well to note.

If I have a question if a record is stereo or mono it does not go under my RPX without first being tried with a stereo cartridge played in the vertical mode. If I hear much, it does not get played with the RPX.

Phil

The insistence by the devotees of "real mono" cartridges that their mono switches with a stereo cartridges do not rival their mono cartridges is testomony to the notion that the mono switch is not always optimum.

Series wiring, or well devised voltage summing, marks a significant step forward, and toward convergent opinions.

Proper true mono carts have restricted vertical compliance. Whether this is a good or bad thing is debatable, but they are then bona fide. You then can't play stereo pressings on them, for obvious reasons ! If one does buy a true mono cart, this is a crux issue, not all implement this feature. I think the DL-102 is still in production, though I've not tried it, that has crossed my mind.

Personally, series wiring/proper voltage summing gets it done.

[steve195527]

Mr Coffee(polite enough?)
Firstly I have never said or implied that you are stupid,crap or anything along those lines and I don't recall saying(writing if you feel like being pedantic!) a a mono switch was optimum,if I did can you point out where?I think I said simple??I will have to check later,now you start criticizing me for run on sentences,didn't realise you'd moved on to wanting things written grammatically correct,I am beginning to realise what some comics mean when they say Americans don't seem to "get" sarcasm(which apparently you claim you're an expert at!)or irony
Steve

[Coffee Phil]

Steve, I really don't care if you can put a sentence together or not. Like it or not you just may be taken more seriously if you would make some effort to put a sentence together. An added benefit might be that readers would be able to actually figure out what you are talking about.

By the way what have you been talking about in this string?

You seemed to point out that mono records can be played by invoking the mono switch on a stereo system. OK, don't most (nearly all) of us here know this? You can play them in stereo as well. So what. The point of this string is to investigate methods to play mono records with stereo cartridges with the performance of mono cartridges. Have you brought anything relevant to that discussion or just added clutter to reduce the signal to noise ratio.

If you really don't think that the subject of this string is a worthwhile pursuit (it is hard to tell with the gibberish which you write) why are you bothering us with your prattle?

Phil

Mr Coffee(polite enough?)
Firstly I have never said or implied that you are stupid,crap or anything along those lines and I don't recall saying(writing if you feel like being pedantic!) a a mono switch was optimum,if I did can you point out where?I think I said simple??I will have to check later,now you start criticizing me for run on sentences,didn't realise you'd moved on to wanting things written grammatically correct,I am beginning to realise what some comics mean when they say Americans don't seem to "get" sarcasm(which apparently you claim you're an expert at!)or irony
Steve

[steve195527]

what is actually your problem? all I said basically that there was a simpler way of playing mono records,and you in various posts have resorted to kind of veiled personal attacks on me,if anybody already has a phono stage the method I suggested is simpler than going ahead and building your pre(well I think it is)and has you have said riaa eq is adequate.
If a thread is started is nobody allowed to have a different point of view or suggest anything alternative to your or lds ideas?Its as though all expect from any poster is adoration and if that isn't forthcoming you take offence,why?