Is this a "what is the best phono stage" thread or is it a debate on very vintage vs less vintage (because a 25 year old phono stage design does not fit the conventional notion of "new", not that there is anything wrong with that) vs really new?
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I have no dog in the fight, but some would argue that it takes some circuitry to make playback using a strain gauge conform to the RIAA pre-emphasis that is built into every LP during the production process. In other words, without some filtering the strain gauge output won't conform closely to RIAA. Whether you can hear that error or not is a matter for dispute.
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Arnieco, your thesis is the opposite of Pani's.
Any phono stage requires lots of gain, more than any other audio component, and a filter that conforms to the RIAA standard de-emphasis curve. Except for tubes, today's parts (discrete transistors, ICs, capacitors, resistors, inductors, diodes, etc) are simply superior to even the very best available 50 years ago. Furthermore, the RIAA standard has not changed since the 50s, and there are only so many ways you can build that filter into a phono gain stage. In fact, there are on line calculators that would allow anyone to build an RIAA network any of several ways. The designer does not even have to be a genius. So it stands to reason that today's electronics can be superior to anything available 50 years ago, if the manufacturer cares enough. But likewise I think the old gear can be modernized using the superior parts now available. So there is no real issue or certainly no tragedy.
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I think your experience must be limited, and I disagree with your premise. Not to say those vintage units were better than what we have now, but only to say you might be surprised at the similarities between old and new circuit designs. We simply have better parts today and the benefit of hindsight. For one example, the Marantz 7C originally used selenium rectifiers, because that’s what they had available. If you simply upgrade the rectification, the SQ takes a leap forward.
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What Dover said. I can give you some "obvious" advantages of a full function preamplifier vs separate line and phono stages. Provided you allow for the luxury of an outboard PS for the full function preamp, I would argue that is the inherently superior configuration, all other things being equal of course.
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The fact that most audiophiles used a "full function" preamplifier back in the 60s, 70s, and even into the 80s, rather than a dedicated phono stage does not in my book mean that phono was taken for granted or given the short end of the stick. In fact in my view the current trend toward separate linestages and phono stages is to some degree a way of extracting more dollars from audiophiles, on the part of manufacturers. There is no reason why a preamplifier, including both a line and phono stage of the highest quality, cannot exist on one chassis. To get to Nirvana, most such gear uses an outboard power supply. A linestage is a very simple add-on to a great phono stage. When I see $20,000 and up stand alone linestages, I am shocked. Shocked I tell you!
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The reason "NFB" goes hand in hand with "active" gain in a phono stage is that by implementing NFB there is an inevitable loss of overall gain. (With NFB, some of the voltage output of the stage is reverted back to the input or some earlier stage in the circuit. Thus there is less net voltage gain at the output.). So an extra active device is implemented somewhere in the RIAA filter to compensate. But this has nothing to do with what parts one chooses to build the circuit (capacitors, resistors, or inductors).
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Leben is free to invent jargon but a phono stage with NFB uses C and R to effect the NFB. Hence it’s still a “CR” phono stage. But now I see where you got your idea. Like Dover said, you can also implement RIAA using inductors, plus R and C. There are even a very few that use LR.
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So I am trying to define some terms. The only meaning of "CR" as applied to a phono stage is to indicate that the RIAA filter is effected with capacitors and resistors. To say that the phono stage incorporates NFB or does not incorporate NFB is another matter entirely. With or without NFB, a CR stage uses capacitors and resistors to effect an RIAA filter.
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The term “CR filter” as applied to an RIAA network means only that the RIAA curve is achieved using capacitors and resistors (also including the input or output impedance of a tube as part of the filter). Such a circuit can be passive or active and can use NFB or not. NFB and CR are two entirely different descriptors for the phono circuit.
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One could write a thousand words on this subject, but suffice to say that while no one can say that your dissatisfaction with modern phono stages is "wrong" (because you are entitled to that opinion), one might fairly say that your thesis for why there is a dearth of superb phono stages (in your opinion) is skating on thin ice and maybe not worth debating. I wish you good luck in finding something that finally makes you happy, but ask yourself if that is really possible. I personally have found that by first educating myself on the relevant aspects of electronics, I have been able to modify commercial gear that is already very good and bring it up to a level of performance that I find very satisfying and which doesn’t leave me yearning for anything better, though I try to keep an open mind in case something better does come along. So far, current drive (for one example) as represented by the few such units I’ve heard, is not an answer. But then again, I am not about to spend $90,000 on a phono stage.
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Every phono stage in history up to about 10 years ago used CR type RIAA filtering. The Citation IV was pretty nice for an early SS effort. HP loved it, I think.
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I recall driving in the dark in rural northern Virginia with a good friend of mine, also a crazy audiophile, to find the home of a guy who owned the PF C7, so we could have a listen. I think he was a dealer who could also sell us one. And you are correct; it was a cult piece for a while. Once we got to the destination, neither of us was blown away by the SQ, but there were the usual caveats about the downstream equipment including speakers that would make it unfair to judge from this temporal distance.
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It was the Audio Research SP3, 3A, 3B, 3C, etc, that captivated the premier audio journalist of the 70s, Harry Pearson. Not the SP6 so much. I remember when a friend bought an SP3, because he worked in an audio salon and could get a big discount. Lots of 12AX7s in there. And Bill, you are correct; there is no point to this thread.
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It's no secret that tube phono stages tend to have much higher phono overload tolerance compared to SS ones. However, that is rarely a problem when the driving cartridge is a typical LOMC type. It's when you pair a SS phono with an MM or high output MI cartridge that overload problems can arise.
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Pani, I don't know what country you live in, but in the USA, when LOMC cartridges were first introduced in the early to mid 70s, most audiophiles owned phono stages with only MM levels of gain. Everyone needed a gain booster of some kind in order to appreciate the new idea in cartridges. At that point in time, the first products in the US market were not SUTs, as I recall. They were "head amps" or "pre-preamps", most prominently I remember the one marketed by Mark Levinson and designed by John Curl, the JC1. For tube aficionados there was also the Counterpoint SA2, eventually. I owned one; it was noisy but good sounding. SUTs came along later, at least here in the US. Someone mentioned the MFA Luminescence C. I owned two of them (consecutively, not both at the same time). While it was "good", it would not hold a candle to any of the more modern phono stages I have owned and used extensively, to include Raul's 3160 Phonolinepreamp, the Atma-sphere MP1, the Silvaweld SH550, the Manley Steelhead. Not that any of these could be regarded as recent designs, if you define "recent" with a 5-year envelope. Sometimes nostalgia makes us see with rose-colored glasses. But on the other hand, RIAA has not changed and the subject of how to effect the RIAA filter has been done to death (with resistors and capacitors, or with R, C, and inductors, or with inductors and resistors, or in the digital domain, or using an IC which may effect any of the preceding components to get the job done). So, yes, there has to be some me-too-ism in the most modern designs. So why is there a bee in your bonnet?
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From where I sit, it seems that audio components of all types evolve more or less in parallel with each other: in fits and starts. What's new in phono stages is the idea of current drive and the implementation of integrated circuits, not discrete transistors or tubes, to do the job. But current drive has not and probably will never drive out voltage drive as a way of amplifying the meager output of a LOMC cartridge. As for the RIAA curve, it's a darn good thing that standard was adopted nearly universally by the late 50s. Otherwise we would have another thing to argue about. Some agreed upon algorithm for pre-emphasis and de-emphasis was essential owing to the nature of magnetic phono cartridges.
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