AudiogoN Forums: What Makes a Good RIAA or Line Stage?

What Makes a Good RIAA or Line Stage?

Hi Doug,

In a currently running thread on a certain RIAA / Line stage beginning with the letter "E", some very provocative comments were made that are of a general nature.

I fear that this conversation will be lost on the many individuals who have soured on the direction which that particular thread has taken. For the purpose of future searches of this archive, those interested in the "E" thread can click this link.

For the rest of us who are interested in some of the meta concepts involved in RIAA and Line Level circuits, I've kicked this thread off - rather than to hijack that other one. In that thread, you (Doug) mused about the differences between your Alap and Dan's Rhea/Calypso:

... the Alaap has the best power supplies I've heard in any tube preamp. This is (in my admittedly unqualified opinion) a major reason why it outplayed Dan's Rhea/Calypso, which sounded starved at dynamic peaks by comparison.

Knowing only a bit more than you, Doug, I too would bet the farm on Nick's p-s design being "better", but know here that "better" is a very open ended term. I'd love to hear Nick's comments (or Jim Hagerman's - who surfs this forum) on this topic, so I'll instigate a bit with some thoughts of my own. Perhaps we can gain some insight.

----

Power supplies are a lot like automobile engines - you have two basic categories:

1. The low revving, high torque variety, characteristic of the American muscle car and espoused by many s-s designers in the world of audio.

2. The high revving, low torque variety characteristic of double overhead cam, 4 valves per cylinder - typically espoused by the single-ended / horn crowd.

Now, just as in autos, each architecture has its own particular advantage, and we truly have a continuum from one extreme to the other..

Large, high-capacitance supplies (category 1) tend to go on forever, but when they run out of gas, it's a sorry sight. Smaller capacitance supplies (category 2) recharge more quickly - being more responsive to musical transients, but will run out of steam during extended, peak demands.

In my humble opinion, your Alap convinced Dan to get out his checkbook in part because of the balance that Nick struck between these two competing goals (an elegant balance), but also because of a design philosophy that actually took music into account.

Too many engineers lose sight of music.

Take this as one man's opinion and nothing more, but when I opened the lid on the dual mono p-s chassis of my friend's Aesthetix Io, my eyes popped out. I could scarcely believe the site of all of those 12AX7 tubes serving as voltage regulators - each one of them having their own 3-pin regulators (e.g. LM317, etc.) to run their filaments.

Please understand that my mention of the Aesthetix is anecdotal, as there are quite a few designs highly regarded designs which embody this approach. It's not my intent to single them out, but is rather a data point in the matrix of my experience.

I was fairly much an electronics design newbie at the time, and I was still piecing my reality together - specifically that design challenges become exponentially more difficult when you introduce too many variables (parts). Another thing I was in the process of learning is that you can over-filter a power supply.

Too much "muscle" in a power supply (as with people), means too little grace, speed, and flexibility.

If I had the skill that Jim Hagerman, Nick Doshi, or John Atwood have, then my design goal would be the athletic equivalent of a Bruce Lee - nimble, lightning quick and unfazed by any musical passage you could throw at it.

In contrast, many of the designs from the big boys remind me of offensive linemen in the National Football League. They do fine with heavy loads, and that's about it.

One has to wonder why someone would complicate matters to such an extent. Surely, they consider the results to be worth it, and many people whom I like and respect consider the results of designs espousing this philosophy of complexity to be an effort that achieves musical goals.

I would be the last person to dictate tastes in hi-fi - other than ask them to focus on the following two considerations:

1. Does this component give me insight into the musical intent of the performer? Does it help me make more "sense" out of things?

2. Will this component help me to enjoy EVERY SINGLE ONE of my recordings, and not just my audiophile recordings?

All other considerations are about sound effects and not music.

Cheers,
Thom @ Galibier

Thom_mackris (Threads | Answers | This Thread)

02-24-07

Responses (1-50 of 98)

Click title to read one, or click date to read all below it.

02-25-07 Thom, sheesh, i'm glad you didn't title your thread "h ... Dougdeacon

02-25-07: Rauliruegas
Dear Thom: IMHO the audio device whole design is what determine which kind of PS do you need.

Which are the voltages/current where the active parts run optimal for the best quality performance, overload margins, we can run those active devices full or at 30% of their specs ( like in the Essential 3150 ), what are the current/voltage needs in the worst stage, cascode source/fountain or not, type of regulation and filtering, how many ps stages, gain stages, needs on output level, distortion/noise levels, chokes or not, whole needs of the whole circuits, separate ps for each " stage " or not, circuit running in class A or what?, ps " power on " all the time or not, etc, etc.

As you can see there are more a lot more subjects than only capacitance. A good ps has to take in count those subjects and many more ( including the ideal capacitance number ) and the " secret " in a good ps design is to optimize any single ps area.

A good audio device design with a bad ps design will sounds bad and a good audio device design with a good ps design will be sound superb.

regards and enjoy the music.
Raul.
Rauliruegas (System | Reviews | Threads | Answers | This Thread)

02-25-07 Hi doug, do you have any pictures of your system? i think it ... Acoustat6

02-25-07 Hi raul, indeed, holistic thinking is required - both in li ... Thom_mackris

02-25-07 Hey doug, what kind of car should i drive??? o o . Nrchy

02-25-07 Atmasphere recently shared some interesting thoughts on the ... Unsound

02-25-07 Bob, thanks for your interest. i've been promising to post ... Dougdeacon

02-25-07 Nrchy, i didn't know you owned a car. once you've driven a ... Dougdeacon

02-25-07 Other designer's comments? well, i think you guys got it ri ... Hagtech

02-25-07 Hi doug, thanks for the response. i am looking forward to se ... Acoustat6

02-25-07 I have been smitten by tom evan's work for several years. hi ... G_m_c

02-26-07 Hello, my .02 1- there are no perfect supplies or audio ampl ... Ndoshi

02-26-07 . thom, great thread. . doug, nice acceptance speech. . nic ... Cello

02-26-07 Thanks to you designers for posting your thoughts. good one, ... Dan_ed

02-26-07 The idea that power supplies somehow compare to engines fall ... Atmasphere

02-26-07 I cannot contribute to a technical discussion here, but can ... Whart

02-27-07 Whoah, thom! look what you started here. i have to disagre ... Hagtech

02-27-07 A line or riaa stage could be characterized as "good&qu ... Jmaldonado

02-27-07 Jose, or anyone else, have you correlated riaa error to colo ... Dan_ed

02-27-07: Rauliruegas
Dear Dan: Absolutely and José and I already tested about, the colorations/distortions/degradation are differents depending where in the frequency range are those inverse RIAA eq deviations.
Almost all phonolinepreamps have its own " colorations " other than the RIAA eq but the ones in the RIAA are more " be present at " because any single frequency deviation affects almost three octaves and this three octaves deviation we noted like a coloration, this special coloration is really a degradation to the cartridge signal because those frequency deviation does not exist in the cartridge signal.

One of the first critical and important task in any phonolinepreamp ( is one of the reasons why they exist ) is to mimic in accurate way the RIAA eq, this inverse RIAA eq must be that " mimic/accurate " to be ( at least in this stage ) truer to the recording .

A good phonolinepreamp IMHO has to have a inverse RIAA eq. deviation no more than 0.05db from 20 to 20kHz.

Our Phonolinepreamp RIAA eq deviation spec is: 0.015db but normally we are below that figure. Obviously that this spec not tell us how the audio device will sound, José already explain other very important subjects to have a good quality performance in a Phonolinepreamp device.

Hagtech, I agree with you about the misunderstood when we name " balanced " to a phono cartridge, it is not, our design is fully differential input to output and the connection is " floating ".

Regards and enjoy the music.
Raul.
Rauliruegas (System | Reviews | Threads | Answers | This Thread)

02-27-07 riaa eq deviation no more than 0.05db why? just how many c ... Hagtech

02-27-07: Rauliruegas
Dear Thom: About the line stage and specially in an analog audio system the whole design has to be very carefully and almost perfect in every single block on the line stage.

When we begin the Essential 3150 Phonolinepreamp design we don't start with the phono stage but with the line stage, one of the reasons was that the signal that comes from the phono cartridge not only has to pass through the phono stage but through the line stage too and at this line stage we have to take care that the signal does not " suffer " any or almost any degradation, from this point of view the line stage is critical at the same phono stage level design and that line stage has to be optimal in all circuit/operation parameters to conserve ( at least ) the same quality performance that comes from the phono stage, very hard to achieve but IMHO this has to be our target about. The people that already hear the Essential 3150 comments that the performance is good not only with analog source but with digital source too.

Regards and enjoy the music.
Raul.
Rauliruegas (System | Reviews | Threads | Answers | This Thread)

02-27-07: Rauliruegas
Dear JH: I respect your point of view and I understand it.

My point of view is a little different: I'm looking for the best don't distorted/colored sound performance, the high deviations in the RIAA ( as you say ) have to be added to many other deviations in the whole audio system and this means that when the sound comes from the speakers what we are hearing is the original signal plus/with a exponential deviations/distortions added.
What happen if any one of us try to remove or at least take to a minimum all those frequency deviations/distortions in any single link in the audio chain?, IMHO all of us will be nearest to the recording and nearest to the live event: this is my target and this is what we try to do in our designs, nothing less: a very hard task btw but with lovely quality sound reproduction rewards for all of us.

We are starting the amplifier and tonearm design and that is our first target in those designs: we don't care if before or after our audio devices the deviations/distortions are bigger, as a fact this subject is what promote in José and I the Essential 3150 Phonolinepreamp self design.

Regards and enjoy the music.
Raul.
Rauliruegas (System | Reviews | Threads | Answers | This Thread)

02-27-07 Hi all, it's great to get some brilliant designers involved ... Thom_mackris

02-27-07 Ok- i have to clear up some misconceptions: the reality is ... Atmasphere

02-27-07: Rauliruegas
Dear Thom: +++++ " I too have to wonder about the necessity of obsessing over small fractions of a dB in RIAA accuracy when in room speaker response varies by such huge amounts... " +++++

The proof is is on the hearing and you can heard it through the Essential 3150, as a fact we heard at your place.

+++++ " experiment and introduce larger and larger RIAA errors ... " +++++

We already do it ( in some ways and not in perfect way ) and that is why I speak in absolute terms about.

Again, your quality sound reproduction targets/priorities ( like JH ) are a little different from ours: we are looking for the perfect sound reproduction, perhaps we never achieve that target but in all ways we will work hard to be the nearest that we can and the inverse RIAA eq. accuracy is one of the targets that help to achieve that very high target.
We can't tolerate distortions/colorations/noises everywhere and we can't accept ( in any way ) that because the speaker/room interaction produce big frequency deviation then we don't take seriously what happen in other links in the audio chain taking in count when we have the control and the knowledge for lower that distoritons/colorations/noises in the Phonolinepreamp and in the future in the amplifier and tonearm.
Thom sorry but I have to disagree with you on that subject: every single " sand grain " is important, the inverse RIAA eq. accuracy in our Essential 3150 is only one way to lower the colorations in our design we have several other subjects that help too to lower those colorations/distortions/noises.

Regards and enjoy the music.
Raul.
Rauliruegas (System | Reviews | Threads | Answers | This Thread)

02-28-07 Thanks ralph (about balanced) ... yours is a different pers ... Thom_mackris

02-28-07 "riaa eq deviation no more than 0.05 db... why?" ... Jmaldonado

02-28-07 The magnitude of riaa error is not particularly useful unles ... Jcarr

02-28-07 Interesting reading, a bit heavy on methodology but the edit ... Ndoshi

02-28-07 Thanks ever so much for visiting this thread, jonathan. you ... Thom_mackris

02-28-07 Hi thom, having been in the business of balanced phono produ ... Atmasphere

02-28-07 again, your quality sound reproduction targets/priorities ar ... Hagtech

02-28-07 Yes, the beauty of the marketplace is that we all have choic ... Thom_mackris

02-28-07: Rauliruegas
Dear Thom: Fortunatelly, like JH told us, there are different " roads " to meet the " border " and the freedom to do it.

Any one has its own " principles and priorities " and music bias in the sound reproduction.

Thom IMHO the best noise is no noise. Now, if we can't dissapear that noise then a good noise is " better " than a bad noise.

We are not " specs/number " lovers per se, but in some way we have to reflect what we are hearing through our designs.
We think that our designs not only have to " sounds great " but to measure great too and if we could achieve both targets that's will be great, don't you think?

I agree with JH about the emotional link with the music through and audio system, with out this interaction between the music and us it does not matters specs or design.
We try hard to have that link in the sound reproduction perception and at the same time to meet very low noise/distortions/colorations and accuracy ( like in the RIAA eq ).

Thom, I know that in theory almost all designers have ( between others ) these targets on mind but when we heard at those designs and when we read the specs I almost always ask me where/why some of them loose those targets. I'm not saying that we are perfects, far from that, but maybe we take care more in deep about simple " things " in the design philosophy, like José told us: the technology is there ready to help us, we only have to use it.

Jcarr: +++++ " The magnitude of RIAA error is not particularly useful unless we also consider the range of frequencies that are affected by the error. in practice, a 1dB deviation that only hits one note is not going to be very noticeable, but a 0.1dB error that spans an octave or more can be quite noticeable. " +++++

I agree with this statement if the RIAA was a line instead than a curve where if one " note /discrete frequency " moves all the adjacents moves too usually more than 2 octaves, we perceive these kind of deviations like a colored sound: these colorations belongs to the audio device but not to the original recording.

I agree with Jcarr about: +++++ " The results of using NFB have a lot more to do with the capabilities and sensibiities of the designer than NFB per se ... " +++++

this is something that José and I discuss several times and the conclusion was the same that Jcarr posted: depend of the designer, where to use, how to use it, how much use it.

Btw, JH and Thom we are not marketing oriented ( we don't manipulate the signal to achieve a " marketing signature " or something ), we are on the audio device design because we like it and because almost all the designs out there can't achieve our goals/priorities in the music sound reproduction in the way we like it, as a fact we design to meet our targets not the consumer ones, we think that through our audio/music experiences, honest on the design, open mind and having the live event like reference we could meet ( or ve near ) the consumer priorities. Maybe we are wrong but it is the way we think.

There is no single parameter that define perse the audio device design, usually all designs have to meet several goals to be " listenable ", how different from others?: that's depends on the designers skills, designers goals and execution of the design in a finish product.

There is no perfect designer/design, we all have limitations of different kind and always have limitations on the quality/tolerances of the parts that we use it: all these parts have limitations and in theory those limitations will be our limitations. Other subject about is the cost/retail price that is a important limitation when we want to share/market the audio device between some price range level.

Regards and enjoy the music.
Raul.
Rauliruegas (System | Reviews | Threads | Answers | This Thread)

02-28-07: Rauliruegas
Dear Thom: +++++ " 2. Will this component help me to enjoy EVERY SINGLE ONE of my recordings, and not just my audiophile recordings? " +++++

This is controversial: if the audio device is " colored " and that colorations don't meet your music sound priorities maybe it does not like you even with your audiophile recordings. If those colorations ( faulty ones ) goes with your priorities you will love with all your recordings, this is fine with me but it is not for what I'm looking for.
Certainly I'm looking to enjoy my recordings, enjoy the music sound reproduction but never with " false " colorations/distortions, I can't tolerate this way because my ears/brain tell me that is wrong that it does not " sound " in that way in a live event ( of course that we are too far from the live event ).

The music perception is totally a subjective event and for this point of view every one have a different opinion and I respect all of those opinions. I'm trying to be nearest to the live event through be truer to the recording on our designs.

Some of us are more tolerant to the noise/distortions than others, I'm not ( and José is less tolerant than me ) and like you posted you are. Two different point of view from two different persons, nothing wrong with that these differences make our day fun.

Regards and enjoy the music.
Raul.
Rauliruegas (System | Reviews | Threads | Answers | This Thread)

02-28-07: Rauliruegas
Dear Thom: This is the subject of your thread: +++++ " What Makes a Good RIAA or Line Stage? " +++++

We all already talk about many subjects for a better audio device design and I think that other one is lay-out, two same designs could sound different with different lay-out. Not many people think seriously about but the circuit board layout is of paramount importance for the performance in audio devices.

Regards and enjoy the music.
Raul.
Rauliruegas (System | Reviews | Threads | Answers | This Thread)

03-01-07 Hi raul, yes, layout is indeed important. jim hagerman is ... Thom_mackris

02-28-07 dan, in my experience the term "coloration" invol ... Jmaldonado

03-01-07 Raul, give it a rest. you're making the same points over and ... Audiofeil

03-01-07 Thom, a replay curve that deviates more from the riaa standa ... Jcarr

03-01-07: Rauliruegas
Dear Thom: With this I'm finish:

+++++ " Your "it has to be perfect" mantra is really tiring me out " +++++, that's what I posted: we are different in this subject but I can asure you that we have more in common than differences about sound/music reproduction.

+++++ " I'm sorry, Raul but as good as the Essential is, it is as colored as many of the other fine RIAA/line stages I rank in the top tier (and the Essential is a fine piece). " +++++

Absolutely, I never speak that it is not only that we try to leave those distortions/bad colorations at minimum, that's all.

+++++ " Please get over it and realize that no one can be all things to all people " +++++

Absolutely, I don't think in other way: I agree.

+++++ " Regarding Audio Puritans, " +++++

No. I'm not: I'm only trying to be better.

+++++ " a very lean and modern sound. " +++++

No, it is not ( I don't know what means " modern sound " ): the sound perception depends on the whole system and my point of view about is that our design is very high revealing of what happen in all the audio chain because that design does not hide almost anything out there, of course that the Essential is part of that audio chain and puts its " grain of salt " about.

The diffrences is how you, other people and I perceive the sound reproduction in an audio system and how be related against the live event or at least near to the recording.

Our attitude/philosophy in the electronic audio design is: truer to the recording and you can't blaim me for that, it is only a way to think that is a little different from yours and other people but there are other people that think in the same way that us: our design goes for that people and we will wait that the other people could change ( a little ) in the future, no our design is not for all in the same manner that horns speakers are not for every one.

Thom, thanks to our differences we have some fun and we can learn a lot about those differences, don't you think?

Regards and enjoy the music.
Raul.
Rauliruegas (System | Reviews | Threads | Answers | This Thread)

03-01-07 Raul:you probably mean "truer to the reference riaa de- ... Gregm

03-01-07: Rauliruegas
Dear Greg: You are right.

yes, we added the 3.18us pole. You can choose it with an internal " switch ".

Regards and enjoy the music.
Raul.
Rauliruegas (System | Reviews | Threads | Answers | This Thread)

03-01-07 Thanks, jonathan. you've filled in the blanks better than i ... Thom_mackris

03-01-07: Rauliruegas
Dear Thom: IMHO thanks to our quest of exellence in the audio performance this thread exist. That quest on exellence bring us here.

I know exactly what you like to hear unfortunately you don't know the same about me.

You are a very well respected TT designer and I wonder what is your quest through your great TT design?

IMHO, I think that we have to look for " evolution " and this is what we are trying to do through our designs.
We always think that there are " out there " a better future for all of us and a better way to make " things ", we are on the quest of it.

I know that we have " to fight " not only against limitations in electronic parts, technology limitations but more important than that limitations in the way people think: this is our challenge, 90% or more of the Essential 3150 ( presentations ) were on tube lover audio systems, not an easy task I can tell you.

We try to be " open mind ", many people ask me why don't tubes?, my answer ( till today ) was always the same: we use all kind of technology that could help us to achieve in the best/better way our sound music reproduction targets and unfortunately the tubes can't help us, not yet: maybe in the future?, maybe: who knows?

Btw, my " hat off " to all non comercial mind tube designers because it is a great really great challenge to achieve " decent goals " in the Phonolinepreamp design with that technology: congratulations!!°

Thom, I know that you are the " boss " in this thread but I'm only trying to help to all of us with a little different point of view, at least from yours.

Regards and enjoy the music.
Raul.
Rauliruegas (System | Reviews | Threads | Answers | This Thread)

03-01-07 Hi thom, i thought i ought to point somethings out. a phono ... Atmasphere

03-01-07 "it made perfect sense to compare component colorations ... Cardani

03-01-07 Thom: regarding playback eq deviations, a small width one m ... Jcarr

03-01-07 Hi raul, if i may offer you a bit of friendly advice, and r ... Thom_mackris

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