Preference for separate phono stages?


Yes, this is a heavily 'theoretical' topic and has (probably) been discussed here ad nauseum.

So, to get on with it: who feels that a single-chassis line/phono stage is a compromise? Do the advantages of a dedicated power supply mechanical and electromagnetic separation outweigh the disadvantage of another pair of interconnects?
paulfolbrecht
Paul, don't you own a Shindo preamp? If that is the case you answered your own
question - it's all about the design and the implementation (and maybe some
added flexibility for separates).

Most external phono stages are better than internal ones just because more
development effort is spent on the phono stage. However, there are excellent
internal phono stages that are well designed and that are difficult to beat with
external ones (for example Shindo and Vacuumstate preamps).
Post removed 
Old AR pre-amps with phono are amazing (ie 6C). However, that is from the true old vinyl days. In the 80's & 90's most phono stages were just an afterthought. The phono stage in a cambridge 640 phono is way better than the internal phono stage on a $3000 sunfire IV pre/pro/tuner.
I do own a Shindo Monbrison - yes. Yes, I know it is possible to make a really excellent one-box line/phono unit, and in a small package at that!

It is, as I said, 'theoretical'. There are too many variables to make apples-to-apples comparisons. (I suppose you could do that if you took the same line/phono design and implemented it both as two-box/two-power-supply and one-box designs.)
the internal phono stage on my entry level Mac 6300 integrated is as good as my Graham Slee Era Gold external.
What about the Aesthetix Janus? I hear good things about it but have no first hand experience. Anybody who does?
Life is full of compromises. Otherwise we all would have four chassis monoblock amps and four chassis line stages and phono stages. The only one who can answer this is you. Yes, isolation offers a better advantage. The questions are: How much better? Can you hear it? How much are you willing to spend for it?

Some will spend hundreds of thousands to get that last 0.5% of sonic purity. Others will spend much less to get most of the way there. As with all things in the audio world, the law of diminishing returns kicks in early and hard.

Cheers,
John
To contribute some more to this topic:

The best people to ask are designers of full function preamps on why they choose a single box solution. Talking to Allen Wright, he thought the main advantage was that one could avoid one more gain/buffer stage and the interconnect when combining pre and phono. According to Allen the problem with separate phono stage solutions is that they should be able to work with a variety of different preamps, requiring different driving and impedance-matching capabilities.

Finally from a noise perspective, I don't quite see the advantage of a separate case. One could always separate out the phono stage in a different shielded section of the preamp and keep paths to a minimum. The only thing that may be worth putting outboard seems to be the power supply IMO. I don't think that putting everything into separate cases is ideal, simplicity and shorter signal paths can have their own advantages, thus a single box solution doesn't necessarily mean a compromise.

Of course, the biggest advantage in separate phono stages IMO is the flexibility. Not only do you have more flexibility in matching pre and phono separately, but most external phono stages have more loading options too.
I find it depends on the phono cartridge. In many cases a separate phono stage w. the obvious benefits will lead to some sonic advantages. In my case, this includes a purity of signal that readibly apparent. I think some from the Doshi crowd could chime in, having owned both full function preamps and them having the separates.
Dear friends: This subject is an almost misunderstood one for many of us, well this is only a simple opinion.

Like in the cartridges that we usually see it like a stand alone performer and now we know that at least the tonearm is an intimate part of it and form a stand alone UNIT the phono stage IMHO it is not a stand alone audio link but part of a UNIT along the line stage ( I'm not talking here in commercial/marketing point of view. ).

It does not matters how good is your phono stage the cartridge signal must pass through a line stage ( before the amplifier ) too so the line stage must be at least at the same level quality performance of the phono stage doing no degradation to the cartridge signal.

The relationship between the phono stage and line stage is so intimate that both units must be " transparent " ( at the same quality level ) to the cartridge signal, it must be synergy between the phono stage and line stage and by synergy I'm reffering to same quality level and the synergy in electrical terms, not the usualy and wrong synergy that many people talk about where the errors in one audio item help to " cover "/compensate for the errors on the other unit: this is not synergy but a mistmatch.

Now, IMHO it is not easy to have a Phonolinepreamp ( integral unit ) because the designer must be a good one in line stage and in phono stage too where both designs has its own and unique challenges.

I can't see advantages on separate units and everything the same a Phonolinepreamp ( integral unit ) IMHO is the best way to go. I think that the " key " is on the phono-line stages quality design and certainly IMHO it does not depends on the phono cartridge like Dgad posted.

I know that everyone has its own opinion in the subject and it will be interesting to hear it.

Regards and enjoy the music.
Raul.
I would expect the Doshi folks to say it's the best there is. It might be - would it be better or worse with two boxes and two power supplies?

(To the person who implied the only trade-off is cost - that's not true: the extra IC needed, with more connections and more wire, is the potential sonic trade-off.)

Basically I was interested to hear from designers who've experimented with both approaches. Keeping everything constant except one vs. two boxes. Strictly academic.
Raul,

I am a big believer in phono stage/ cartridge compatibility. For a simple example, the Ortofon SPU is designed to have a SUT in line. It sounds better this way. Also, your condemnation of the PC-1 earlier... could very well be reversed using a lean, solid state type phono. But the lean solid state phono would not sound best with Dynavector XV-1s or Lyra Titan I. It is all about system synergy. YOu just want everyone to believe that there are absolute bests, when in fact some items that are less than the best, may very well be the best in the correct system and perform adimarably above what you heard in your system. Now..this does not mean that in your system they might be poor, or that in someone elses system you might not like them. It is what it is. I have realized while some like sound A others like sound B. My bias are pretty simple. No hissy tizzy highs or thinness allowed. But too thick is no good either. In that regard certain speakers will throw me out of the room. And so will certain phono stage/cartridge combinations.

Now - changing subject but relevant; isn't it amazing how VdH can tune a cartridge with a few adjustments to bring it into a different league of sound. Even more so, this tells you that even cartridges don't always sound alike due to slight difference in production etc. and thus there is no absolutes.

Hence, my strong push for system synergies. Anyone saying otherwise is just trying to push an agenda.
Dear darren: I understand you and for the most part I agree with you, let me to explain a little about synergy from my point of view ( that it is only that a point of view and not in any absolute terms. ): I can't comment on your SPU example because I don't know the history behind that design and I don't have yet the opportunity to try it in my today audio system.

When you speak of the PC-1 or XV-1 trying to match to a Phonolinepreamp my point of view is that if one of these cartridges ( or both ) needs a special sound " signature " in a Phonolinepreamp to performs at its best this means to me that something could be wrong around those audio items: if the Phonolinepreamp is an accurate/low distortions ( not analytical ) ( no colorations ) design then the cartridge has a little problem ( assuming good tonearm match and right set-up and loading. ) and that cartridge is not up to the task and of course things can be on reverse too when the Phonolinepreamp is full of distortions/colorations/inaccuracies, in both cases there is no synergy.

Darren, if you take a look to the Agon second hand audio item ads you can make a question: why so many and different ( almost new/mint ) audio items for sale? what's wrong?: well maybe many of those persons are looking for synergy and they don't find it yet and IMHO they don't find it yet because what almost all are doing is to buy/try audio items that are compensating the errors of some audio items in their audio systems and with this compensation they think they can achieve that critical and elusive SYNERGY but sooner or latter this kind of " audio attitude " show the " cooper " because the sum/add of two errors ( IMHO ) in my audio experiences almost never give you the right/correct and precise performances.

Do you know how many years that I don't buy audio items like: speakers, amplifiers, phono stage, line preamp, etc, etc ?, too many to remember and why is this?, very simple: I already achieve TRUE SYNERGY through my different audio items where I was and am looking for that true-synergy where I don't have to compensate for anything anymore.
Stay where I'm take me not only a lot of years but a lot of real time testing/trying/changing/etc but the reward is worth any effort on that direction.

Do you think that you already achieve in your system TRUE/REAL Synergy?, I know the answer because I know every single audio item in your system ( but the phono stage ) and I know that you don't have electrical synergy ( example ) between the Wilsons and the VTLs because of its impedances.

Now, I'm convinced that people like you, me and several other ones agree in 80%-90% what must be the quality performance that we are looking in our home music sound reproduction systems, we almost all have more coincident " attitude " about that differences.

I know that nothing is perfect but beyond your opinion, mine or any one else: my quest is for be near that " perfection " and I have to say that I don't accept ( normally ) nothing less, this is the main reason why we design/build the Essential Phonolinepreamp and that's why I have my " old " system running with out the normal tendency to change it.

Anyway, I think that we are talking almost on the same subject SYNERGY but the point is that I speak on true/real synergy and till you achieve it or be near it it will be difficult to understand at 100%.

Regards and enjoy the music.
raul.
Raul,

The VTL amps are in fact synergistic w. the Maxx IIs which have a fairly benign impedance curve. I have had big SS amps that can go to to below 1 ohm and the performance was similar w. the VTL having a more life like sense of harmonics. I also know there are different sounds that I might like better w. different music but for most listening I love my current setup w. in the constraints. Now back to topic, I truly believe a phono preamp must be looked at w. the cartridge in mind. Also having a full function phono preamp in my system to compare to my separate allowed me to understand the synergies. The differences are subtle to most people but for me are the difference between magic and just good music. I have had 6 different phono stages in my system. Some world class and I can easily state that in certain situations each one excelled. I would state that the Raven Phono is the most neutral I have owned w. its sole limitation being gain for extremely low output cartridges. But... for some cartridges which are less than neutral or a system that is less than neutral there exist wonderful synergies at lower price points. The benefit of a separate phono allows certain obvious advantages in terms of system building and upgrades. Those who can find a full function preamp that meets all their needs with the right cartridge should be happy. There is no absolute in this hobby.

In that regard, I do find some cartridges benefit from a SUT, some from SS and others from tubes. That should say a lot. Now in terms of convenience factor, tubes can be a hassle if there are too many and SUTs need to be matched to the cartridge and finally, SS phono stages are more sensetive to load matching than the tube ones I have tried. But this is my experience.
Dear Darren: I don't want to follow argue about because for what I read in what you posted I have to say that we are really talking of different issues and in this way is almost impossible to be near an agreement about.

Btw, how can you tell me that this is a beningn speaker electrical impedance curve?:

http://www.stereophile.com/floorloudspeakers/805wilson/index4.html

maybe for a different amplifiers that your VTLs that has a little high output impedance, please read about here:

http://www.stereophile.com/tubepoweramps/152/index8.html

IMHO I think that there is no synergy ( at least electrical that it is critical to avoid excesive colorations like you have in that amplifier/speaker combination. ) between the maxx 2 and VTls, of course that I respect your opinion but like I told you we are not speaking on the same subject, there is a misunderstood somewhere.

Regards and enjoy the music.
Raul.
who feels that a single-chassis line/phono stage is a compromise? Do the advantages of a dedicated power supply mechanical and electromagnetic separation outweigh the disadvantage of another pair of interconnects?
 
Over the past couple years I've covered four standalone phono stages, two linestages, and one full function preamp with comparisons in different combinations. From my experience, it depends on the equipment - how, and how well, the linestage, phono section and power supply circuits are executed, parts quality, chassis, cables, etc, etc. There are too many variables to establish a general principle that is true the majority of the time.
 
As with most gears, there are synergistic combinations, there are always trade-offs, and there are different personal preferences.
 
That said, the full function preamp designer has a bit of an advantage. He know's what linestage will be used. Granted, makers of separates (ARC for instance) will no doubt achieve a nice level of synergy when their own gear is paired together.
 
Remember that over 50% of the gain in an analog rig will come from the phono section. If signal is lost there, it ain't coming back downstream.
 
The ideal result might be described as coming from an unfettered continuum of gain stages, the contributions of each you cannot detect. Posed as your general theoretical question: What is most likely to yield that?
 
Tim
 
I believe a single chassis CAN be compromised. I believe a separate pre and phono CAN also be compromised. It all comes down to implementation. Additional compromises CAN be too many components in the signal path, remote volume control, single volume/attenuation, single power supply, etc.
Dan and I have directly A/B'd his four chassis Doshi Alaap (phono power supplies, phono circuits, line power supplies, line circuits) with my two chassis one (power supplies, integrated phono+line circuits).

Of course the Alaap's phono and line stages are designed to work together. As Raul pointed out, the most careful matching between gain stages is critical and I believe the Alaap's audio circuits are essentially identical whether placed in one chassis or two. I guess that makes our comparison useful for this thread, since the only difference is the room for extra power supplies.

Dan's was being delivered that very day by Nick so, being brand new and sounding it, subtle comparisons weren't possible. With that caveat, Dan's extra power supplies did provide an increase in dynamic headroom and weight. It wasn't a huge improvement but it was certainly audible.

For those who haven't heard an Alaap that marked an impressive achievement, since even a two chassis Alaap has dynamic headroom which meets or exceeds anything else we've heard. After four years the damn thing can still shock me with its startling leaps from silence to a wall shaking first impact - and Dan's is stronger. Kinda scary. :-)

The choice of interconnects can have an effect with separates, obviously, but it wouldn't necessarily be a negative effect. What if a separates owner chooses wire that's better than what's used in the integrated version? The results could actually be better. That may be unlikely at the level of a Doshi or Raul's Essential, where every component including wire is specified to the max, but in lower performing units it could easily happen. Drop a set of Nordost Odins between two $1K separates and watch what happens. Foolish? Maybe, but probably a big improvement.

Summary: for the Doshi design, four separate chassis provides some increase in an already amazing level of headroom with no downside we could hear, at least not through the newness of the separates. For other designs, who knows? Implementation is everything, here as everywhere.

I'm impressed that you can remember details back that far, Doug. I can't remember what I did 5 minutes ago. :-)

See! No dogma from the "Doshi folks".