Hi Dodgealum,
I think you got my point right on. We all know there are SO MANY phono-stage that ALSO do MM, like BIG DEAL.
It is the TOP effort that becomes of interest. My ML326S modules are doing pretty fine -- BUT I think there can be better to be had, and I think in terms of a tube design. But not another one yet that "sounds really good for the money".
Arthur Salvatore (may he be mentioned here?) insists the best has to be (happens to be e.g. Jadis) inside the pre-amp in any event. So if we take it outside it better be the best --- what ever THAT would be.
Axel
PS: Next we'll be crucified being elitist, I hope not! |
Hi All,
has anyone experience with an Allen Wright 'Vacuum State' phono-stage at all?
Axel |
Hi Lewm,
sorry for having nicked your question, not that I knew. It just becomes the next relavant issue after you get 'closer' with the 'MM prered' thing.
>>> Ideally, I would build an MM phono stage myself, based on a single-ended LCR type of RIAA equalization or based on a true balanced circuit design. There are several schematics available for either topology <<<
Now you nicked MY question, it's actually behind the 'Allen Wright' inquiery. He apparently has some VERY well thought out designs. I think your point is a good one, and that's what I'm planning to do. Build my own and meanwhile listen to my 326 phono-boards (and use them as a referance to improve on)
Thanks,
Axel |
Lewm
>>> Does he sell it as a kit? <<<
I have actually send him an email.
I'll see what comes back.
Thanks for the feedback also.
Axel |
Hi Lewm,
following FYI, (in answer to my query to A.W.):
>>> The balanced phono stage with "floating" RIAA is not usable as a stand alone unit, as it cannot drive a interconnect cable, and requires a fixed 50k ohm loading to have correct RIAA eq. <<<
And:>>> What is your favorite MM cartridge? <<<
Well, I tried to answer that, and even with the few MMs I have it is not so easy to tell. Right now I've switched to a 'Townshend Elite EEI 500 (parabolic)' and it immediately shows, it can do punchy bass and pretty clean treble.
So now, what's your favourite MM cart?
It'd be just interesting to hear, since I've buried the SUT for the moment :-)
Axel |
Lewm
>>> probably a Sumiko BluePoint, originally <<< oh, oh, :-) but that's also an MC?
about time if you get a bit restless to check on MMs, I say...
I have listened to A&R P77, Empire S1000 ZE/X, Shure V15 III VN35MR, Elite EEI 500, AT-140LC, and some bottom of the line AT with conical stylus (not actually much more than the $20 you pay for it).
All this has confirmed for me in my system everything that Raul is on about.
I have also had in my system, DV 20X-L, DV 10x5, Kontra-Punkt A, Jubilee, Windfeld, Dorian, Transfiguration Axia, Orpheus what I recall.
I mention this as I can not lay claim to some 100 plus carts MC and MM, Raul is working with.
Yet, other than that el cheapo $20 AT basic --- every MM was more fluid, musical, and had more 'magic' (for lack of a better word) in my system than ANY of the mentioned MCs.
This obviously made me wonder why?!
Raul, thinks it's just by the nature of the different construction that, given a decent phono-pre, make that difference.
What I'm learning also, there seem NO 'special' MM phono-pres in today's offerings, as all are -can do MM too-.
What I was looking for is a MM stage, differential, floating RIAA, tube, 100, 75 50 (47)k ohm input impedance, 100, 200, 300, 400, 500pF C loading. XLR outputs, Differential (wired) RCA inputs.
No such a thing for only up to 40dB for all I can see.
My current boards are, differential, SS (op-amps 2x) 1 for 40dB plus on for 69dB, no C loading (OK two parallel binding posts), 47k ohm only impedance. It sound pretty good, as it uses the clean power of the ML326S' power supply and is INSIDE the pre-amp.
So, I guess all there is, is to find some 'oldie' pre-amp? Not so sure I actually want to change my 326S (to darn convenient :-)
--- End of enquiry? Could well be...
"At least nobody can say I haven't tried"
Axel |
Well Lewm,
thank you for sharing. Now with 3 'tables why not give a NICE MM a try and let us hear what would be your finding.
It could be most interesting (didn't say rewarding... :-) to have another take by someone of your long standing anlogue background. If only to have some more prespective, and for under $1000 it be just as well :-)
Thanks,
Axel |
Hi Tketcham
>>> To what level of "top" phono stage are you referring? <<<
Simply the best, - second best I already have.
>>> ... is the Jadis the "top" level you were originally asking about? <<<
Raul got this, he is thinking "Essential 3160"...
The Jadis is a still current, just as an example, that's why I mentioned it.
There 'where' other great 40dB stages but ALL gone by now.
I'm really NOT asking about any 'wall-wart' power supply pre's. I thought that was implied. Why even bother to ask then? Like: "Go get one (any one) and call it a day..." :-)
Greetings,
Axel
PS: There are squat (current) 'top' 40dB tube phono-pres out there, and that is already something useful to know. Makes it a proposition to build one's own... a new market gap? |
Hi Fap, Tketcham
>>> ..this quite simple to build design is amazing! <<<
OP-Amps, not part of the spec I'm thinking of.
I realize it's maybe time to go into more detail.
Also, the 'Jadis' would be single-ended also not part of the idea, good as it my be.
Rough spec. would be:
- 40dB
- tube gain stage (max. to gain stages)
- 1 JFET gain-stage? Maybe, to get minimum tube-rush/noise
- or e.g. Lundal trannies to get the first 20dB?
- shunt regulated power supply
- differential circuit (XLR out-puts, differential wired RCA inputs)
- no volume control
- floating RIAA (between + and - of the differential circuit)
- one box design (if at all possible, by use of good screening)
- No PCBs, screened silver wire for internal wiring.
- Good,e.g. WBT connectors
That should cover the basics. What tubes to use, trannie, resistors (Tantalum, or?) is dependent on the circuit design and implementation.
Greetings,
Axel
|
Hi Tom
you ask:
>>> Do you think that a high quality SUT or headamp could provide the gain and loading needed to turn a high end MM stage into a high end MC stage? Or does the use of external transformers or headamps degrade the signal too much to be considered acceptable for a high end phono stage? <<<
To start, a head-amp will be (generally) providing the lesser quality, compared to a good SUT.
(That's why they fell out of favour, years back already --- and today? ~ No need...)
Now to the SUT, and here I guess it will..., become controversial once again?
It is my current experience that a top MM into a good MM(MC?) phono-pre will beat an MC with an SUT into that phono-pre. Given, that we have a top class match between MC and SUT, and a subject all on its own.
Only, and only, if for various reasons of your own, you love that MC, and that low gain phono-pre (and particularly if its a good one!), would I consider the SUT option.
It will not be a bad mix by any means. You'll have more dynamic depth, more bass punch, a bit more harmonic completeness, compared to MC only... so, nothing to scoff at.
Yet a good MM will very likely do it all with a bit more 'EASE', so far what I have found.
I still think, that most (if not all phono-pres just have to try too hard to get most 'everything' from that puny ~ 0.3mV cart voltage into a harmonically complete reproduction OF WHAT IS ON THE VINYL.
Now offer that phono-pre ~ 5.0mV it is just simply easier to get it right, as close as can be. And that in turn applies to the MC plus SUT match, ... with maybe a little less ease.
What will go missing with the MC / SUT setup is some micro detail swallowed up by the SUT's leakage inductance, parasitic capacitance, etc. it can be noticed by a less sharply carved out image presentation -- some would argue is unnatural anyhow (like stuck with your head in the microphone).
Yet, plenty people find that's what's needed, else it does not qualify for 'Hi-End' and I'm not going to argue...
Now all the electronic fundies are gonna jump up, but counting ELECTRONS (in a phono-pre) literally, if you consider micro-information coming from the vinyl by 0.3mV, 5cm/sec @ 1k Hz is actually one MIGHTY tall order, 'cause a lot is a the 'single electron' level before it is 'pumped up' and equlised. One electron gone missing = information lost.
I hope this answers your question.
Greetings,
Axel |
Funny that no one has mentioned the new Passlabs XP-15 as yet.
It's SS, but seems to be close in a number of other 'parameters' mentioned. Good price too $3'800...
Any comments?
Axel |
Hello Kirkus,
I've printed you notes, and will study them.
There is some most valuable information based on your long experience as I can see on some quick glancing through.
Thank you for sharing!
Axel |
Hi Tom
you say:
>>> it may necessitate a range of dedicated MC phono stages if someone wants to listen to a variety of LOMC cartridges <<<
I can not support that logic as e.g.: all women are people, there for all people are women? :-)
Loading with MC stages and to some smaller degree loading of SUTs (secondary and primary side) takes care of the variations in MC's DCR and output voltage. Of course a mismatched SUT/cart can not be made to work by loading e.g. if it would overload the phono-stage.
Greetings,
Axel |
Tom,
I guess 'switching' means loading in your context, yes?
Loading an MC with 100, 500, 1k ohm for example makes little difference as to the phono-pre used as such.
The mechanical issues involved will.
Soldered Rs are best, than clamped in some binding posts, then the 'mouse-piano' i.e. the switching you seem to refer to.
The same would apply (to the phono-pre) using 47k, 50k, 75k or 100k phono-pre input impedance 'switching/changing' for MMs only.
The issue with MCs is rather to have a phono-pre that "can count electrons" (if no SUT is used).
Apparently only few designs are THAT good after all. Mostly noticeable in the difference of those parameters I mentioned that are improved, when an SUT is used with a Low MC.
Often a lack of dynamics is noted if an MCs output is on the low side - use an SUT, and THAT problem is GONE.
When using an MM there are different things at work.
Mainly due to the 'high' cart voltage output --- BUT also because they are a more 'reactive' load, usually 600 - 3.5 ohm DCR, 700mH as ~ 20uH with an MC and compared to only ~ 2 - 6 ohm with LOMCs).
That is why a TOP MM stage would ask for a different design if strictly dedicated to MMs.
No SUT can be used, single ended (SE) MIGHT be better. I'm as little sure about this as Lewm is and it might have to do with the 3-6dB lesser noise in SE design --- which then again might just be made worse by using common ground that can be noisy.
Also 'floating RIAA' as in a differential circuit between +/- is not an option either.
Greetings,
Axel |
Hi Lewm,
>>> With an MM phono stage, we should all be using a 100K load <<<
Another reason for this thread's subject.
I mean, WHICH phono-pre, of one-serves-all, has a 70k and/or 100k ohm input impedance option I ask?
I know Raul's Essential 3160 has, but that is a non-main-stream item.
As to 'switching degradation' I had a PS Audio GCPH using some pretty convenient switching, and now a pain-in-the-butt ML phono-module using internal binding posts or some jumpers.
But as you say, how could I have tested the GCPH's performance without the switches for gain and loading?
All I know is, that the ML modules sound better --- but because of the switches?
Raul and Co. might have some contribution in sharing their findings, wouldn't they?
Axel |
Hi Tom,
you say:
>>> Just seemed like a similar question in that having phono stages designed specifically for the type of cartridge engine makes sense. <<<
I have the idea that Raul will be the person to explain to you in his words why he has opted for two **dedicated** phono-pre option in his 3160 and NOT a one-serves-all (just with a jumper to switch from 40 to 60dB).
Having read all my and Kirkus' comments should have made the point, but let's see if Raul can put it into a 'nut-shell' for us.
Greetings,
Axel |
Tom,
>>> ... confused a bit by your comment that the 3160 has a jumper to change from 40 dB to 60 dB of gain.<<<
That is not what I said, neither implied, since the 3160 has dedicated (like two seperate units) MM & MC stage(s) inside the line-pre-amp.
Jumpers are just somewhere in the hierarchy of 'switches' and perhaps a bit preferable (but not for comfort). They are normally very closely placed to where things need to get 'switched', Raul will NOT have any of those either, I'm sure.
A solder joint, or no joint at all, is still THE BEST (as long as it does not create a diode :-)
A. |
Hi Kirkus
VERY insightful, thank you. I'll have to chew over all of this with my 'consultant engineer':-)
But now one question: Common mode rejection, yes well... everybody points this out on the differential circuits, and nobody is running 20m or more ICs (other then in the professional world).
But it was the OTHER item:
The inevitable and unavoidable 'ground contamination' influences of capacitors etc. that makes the other argument for differential/balanced vs. unbalanced.
It seems this (at least to my current take) is to be weighted against the ~ 'imbalance(s)' in a balanced design.
A lot could be said about some renown reviewers / testers having found, that even in a balanced design (not pseudo) the single-ended still sounded more 'natural'.
Why? It is that the differential circuit also cancels even-order harmonics in the process of common mode rejection, so you wind up with a bias toward odd-order harmonics, and that is not so 'natural' to our ear.
Be nice to have your take on this side of it.
Thanks,
Axel |
Kirkus,
y.s.:
>>> I feel that in a high-quality phono preamplifier, ALL harmonic and IM distortion should be completely and totally buried in the noise floor, which in itself should be very low. Yes, low-order and even-order products are less disconcerting to the ear . . . but who wants any of it at all?"
Some would not agree with this necessarily, since other then in digital designs, harmonic distortion is never buried in the noise floor completely.
It seem current understanding that harmonic distortion should rather RISE evenly (even- and odd-order equally) with increasing output, rather than then decreasing with higher output. (Output rise as from cart input rise)
Two notable designs come to mind by PassLabs (SUSY, Super Symmetry) and the 'cyclotron' (re-invention) by the Thorens TEM-3200 mono blocks have proved that to be correct.
Item: 'ground contamination' as you pointed out is more of a challenge then maybe generally accepted? And we are not talking of major ground loops.
I is VERY difficult if not impossible to prevent some potential differences occurring in components (and amongst each other) during all states of operation. So they best possible directed by use of e.g. star-ground schemes. The point is, there are still caps (to ground) involved and caps have power factors, creating a far less 'clean' signal path then the dedicated (-) in a balanced design.
The noise floor of my ML326S is below 90dB (balanced). I think the issue is the 'tonality', influenced by 'combing out' harmonic distortion selectively. It is why even a MUCH noisier single-ended design often will sound 'better, more natural' then does a balanced one. (I speak from experience)
The trade-off is most always balanced = more dynamic, and 'cleaner' vs. unbalanced = better harmonic completeness, more natural sounding.
As to hum caused by 'unbalanced' MM cart output impedance. Well, I think that the more expensive carts we are speaking of (Raul mostly), those have always excellent channel balance, often better than more main-stream MCs with an e.g. <1.5dB spec.
I run MMs into my (balanced) ML phono-board and have no discernable noise (ear to the speaker)!
This at elevated listing level setting ~ 45 (max = 80, grading in dB steps).
Adding 35dB (level 80, that would destroy my ears first, and speakers next!) I can practically NOT hear noise from the listening position (this @ 60dB 'normal' daytime background noise).
I guess, ML is very good at what they do with their balanced designs ---- however, tonality and 'live like' emotionality is not exactly their forte.
One always seems to find that with 'noisier' and most always single-ended designs.
That's where I see the trade off.
Balanced = Hyper-clean and dynamic vs. unbalanced = naturalness, less clean, and better harmonic completeness.
All is of course subject to some generalisations and subject to levels of degree.
Axel |
Lewm,
of course you are right! We are talking one channel at a time, sorry.
>>> ... he was referring to the generally much higher and more reactive impedance of MMs and the fact that these parameters may not be identical for each phase of the output in a SINGLE channel, using a balanced circuit <<<
I see, but then this would be a GENERAL issue with every kind of MM?!
They ALL have a much higher reactive component than any MC.
Now why do you think, do I have NO hum what so ever with a FULLY opened pre, going balanced into a balanced phono-line-pre?
Maybe the answer lies with ML's balanced design then?
Axel |
Well Raul,
my own findings really concur with Martin Colloms', but so be it :-)
A. |
Thanks Kirkus,
gotta get lucky once in a while in this here Audio game.
But as you mention as well, noise is only one facet of it all.
As I noted - tonality is yet another thing. In fact, funny enough it also seem very high on Raul's list of evaluation criteria too :-)
Axel |
Lewm,
yes, I think this could be right.
It again would explain that even some well noted/quoted phono-stage designer(s) like SE.
There was Lamm's Vladimir Shushurin? that stated his clear and decided preference for SE -- but I think he then uses a trannie to change the output to balanced.
His main argument also was 'noise' and could well be what you just mentioned.
The new PassLabs-X15 seem very well regarded (best ever, etc.) would be most interesting to know what circuit it uses.
Axel |
Hi Kirkus,
during an earlier part of the MM, balanced vs unbalanced and common-mode rejection posting the SUT subject came up shortly.
It may not fully relate to this thread, but let me try.
You mentioned in your example a 50 ohm SUT input impedance with a 5 ohm DCR MC cart. Explaining some advantages with regard to hum rejection, and how this of course can not be realised in an MM specific phono-pre (as a trannie cannot be used etc.)
Would you share your explanation, why with the use of an SUT (in my listening) some other parameters then hum are notably changed/improved i.e.
- more dynamic depth (better hi/low SPL differentiation)
- more powerful bass
- more hall/room information, stage depth
I could add some more, but it should do for this example.
Cart parameters:
3 ohm DCR
0.3mV output @ 5cm/sec
SUT parameters:
1:31.6 ratio (30dB, i.e. natural impedance 47ohm with 47k)
- primary DCR 1.5 ohm
- secondary DCR ~ 65 ohm (as I recall)
- primary loading 13 ohm (paral. with 47 ohm nat. imp.) i.e. 10 ohm that the cart sees.
If nothing else, it could high-light how very different a MC stage might just be as compared to an MM stage. So we'd be back at the subject, of sorts.
Many thanks,
Axel
|
Hi Kirkus,
thank you.
??? >>> ...without re-opening the whole SUT/non-SUT debate. <<<
Not aware of that debate. Is there a thread I can look up you'd recall?
At least as far as MMs are concerned: THERE IS NOT DEBATE ABOUT SUTs :-)
Axel |
Kirkus,
since I was rather too curious, I did some back-tracking on the subject in some related A'gon threads. What I come up with is, for best sound for the $$$:
1) 'affordable' phono-stage with MM
2) good stage with MM
3) good stage with SUT and MC
4) top stage with MC
2) and 3) mybe on par, and MC = LO MC > 0.4mV
Raul has his take on what comprises a 'good' stage (3160)and 0.01dB deviation in RIAA --------- other then the one he uses, I've never as yet seen one measured that could do this.
So I can at best call my own lot 'affordable'. ML claims +/- 1dB deviation, my previous GCPH claimed 0.25dB deviation.
Interestingly, the ML sounds better, and maybe due to using the 326S power supply.
Also some other acclaimed stages do rather poorly in this particular measurement.
More food for thought?
A. |
Tom,
re.: Reflex & Elevator...
>>> But apparently it's not what Axel considered "top end" when he asked the original question.<<<
Actually I'm not really in a position to be the 'judge' on what a "top-end" MM-stage comprises (other than $$$/hear-say/etc...)
But what I did say earlier on is:
- "What I come up with is, for best sound for the $$$:
1) affordable phono-stage with MM (Reflex?)
2) good stage with MM
3) good stage with SUT and MC (Note: not mentioned headamps i.e. Elevator)
4) top stage with MC
2) and 3) maybe on par, and MC = LO MC > 0.4mV " -
This would be in favour, $$$wise, of using MM with MM-only stage.
I think we'll struggle to get an answer to whether a "top-end" MM stage even exists (other than 3160), AND if it makes actually as big a difference in sound, compared to the more affordable ones (e.g. Reflex)
Note: There is absolutely NO DOUBT in my mind, that due to the low output voltage of MCs, only the-best-of-the-best MC-stage will actually be good enough to do justice to an MC's potential.
Maybe, because good MM's, due to the higher output, make for simpler, less costly, yet top performance stage designs?
Like: Single ended, JFET & tube (2 gain stages only), ~ 1dB RIAA error, good clean power supply ---- finito?
If that was so, there'd be plenty to pick from, and it would 'sink' plenty of MC set-ups with only so-so MC-stage. Everyone can get back to vinyl, without another mortgage on the house :-) |
Hi Saudio
EAR 324, a good one in the context of MM - alas it showed some issues with too little head-room in the 20Hz region. Not a lot going on down there mostly, but still.
The 88PB would be more ===> MC targeted I'd guess. |
Hi Kirkus,
as always, a thoughtful and well laid out response.
As far as SUTs go, yes they need to be matched, well matched! But if done, they have some 'magic' of their own and can make an MC something more full of 'live' and vibrant.
As to this RIAA 'ping-pong' you say: "Well, error is error . . . and it's always statistically additive in this case"
Not necessarily since there are errors to the (-) and (+) side of the curve, yes?
And we are actually talking about observed 'tolerances' just not quite the same as ERROR, in my vocab anyway.
Now, tolerances can be additive or subtractive.
This would also mean that some of this 'synergy' so often mentioned, is just one of the things that make one cart sound better in a given set-up then in another. |
Hi Kirkus,
>>> ... assume the "perfect storm" where all the errors just happen to add up in the worst way.<<<
"Monte Carlo" analysis, OK... the inventor must have lost it ALL then - worst case.
BUT he did not consider any form of 'synergy'. The importance of synergy has been pointed out over and over, in fact lots and lots of times by Raul himself :-)
Must be some concession to this 0.075% perfection.
I worked in pcb, and later semiconductor assembly, that gives me that practical bias what can be done if it gets 'commercially' viable.
No way to have much better then 1% components on a tape-fed bonder doing SMDs, as I mentioned earlier.
Also no way to start improving tolerances after the stuff (not only SMDs) are on the pcb. (Note: >3x rework = reject)
I have a pretty good idea, that this is where some realism in terms of tolerances has to prevail, meaning ALL hand build, bespoke, and nothing done 'commercially' will qualify --- seriously, that doesn't float my boat yet.
Why? Because a lot of 'bespoke' products have plenty more hidden QA issues then something more 'commercial', where errors have been weeded out to a much higher degree.
|
Hi,
I'm still looking for a clue, given that MM carts like the 'simpler' single-ended designs, and some that find:
- the fewer components in the signal path the better- it could make for a 'simple' but great MM only design. (Don't forget a tube)
In fact, having mentioned Jadis might just be that, alas too much $$$$ for their flavour of genius...
Next up I'd think of Tim de Paravicini's EAR834P MM only, as some would say the step-up for MC could very easily be bettered. So for MM only - no need.
One thing might be power supply 'simplicity' (no regulation at all?), and some other circuit issues, that sprouted a number of aftermarket mods.
Are there any other such designs we could add to this one?
Axel |
Audion Premier?
anyone can tell us something about it at all? |
Audio*n* Premier Quattro ==> 4 Box Pre-Amp, OK, I see :-) |
Hi,
it looks like I'm sorted with my set-up now.
I'm using a V15 III xMR cart going into the 60dB! (40dB sux!!!!) phono-module input (differential) inside the 326S and use unity gain (0dB) setting.
It also balances OK with my CD (390S) XLR only needs to go to +6dB upped input level, no sweat.
Right now I can not see that this can be bettered without changing to a different phonolinepreamp, tubes and all - with the trade-off in loosing a LOT of ML convenience (which I truly DO appreciate :-)
A. |
>>> ... but I bet it's very good.<<<
Apparently if you like it a little bit more 'warm' ---
http://www.positive-feedback.com/Issue11/vinylreference.htm |
