Parasound Zphono Phono Preamplifier Review

[LTig]

seeing these measurements, I have a question:

could vinyl be better that cd audio in any way?

all I can think of is that for example there are vinyl rips with wider frequency range (with sound over 22khz).

are there any other vinyl benefits considering most phono preamps seem to have worse performance that an average DACs (in terms of SINAD at least)?

No. And I still have >1000 LPs and an expensive TT.

 

[Kachda]

I’ve never understood the attraction of Vinyl. If you want to have a physical collection, why not buy CDs? Do people really enjoy all that noise by calling it warmth?

 

[napilopez]

I’ve never understood the attraction of Vinyl. If you want to have a physical collection, why not buy CDs? Do people really enjoy all that noise by calling it warmth?

It's an aesthetic experience. Personally, CDs make even less sense than vinyl to me, and I grew up with CDs, not vinyl.

The way I see it, CDs provide no acoustic benefit over decent streaming services either and aren't aesthetically interesting enough to make me want to build a collection. The cases are small and plasticky.

Vinyl collections legitimately double as artwork, and there's something much more satisfying (to me) about placing a big ol' piece of vinyl on a platter than inserting a little CD into a player.

In my case at least, I don't know if I necessarily enjoy the extra noise, but frankly speaking, it doesn't bother me all that much either.

It's also different, and the process is a bit of a ritual, so those things make me pay attention. If there's one thing I've learned in testing audio gear over the past decade its that the single biggest improvement to sound quality you can make is simply paying attention.

I do the bulk of my listening via streaming, but I've come to realize I often enjoy some of my favorite music more with vinyl. For whatever reason, I find it easier to just focus on the music. Perhaps because I had to make the conscious choice to get up off the couch, look at the artwork, and place the needle on the disc.

I then need to be sure to listen, because I can't just play and pause with a remote. Then midway I need to get back up and flip the platter around. All inconveniences, but they somehow add to the experience sometimes.

Not saying that CDs can't do that for some people, but I suspect vinyl just makes a bigger aesthetic impact, and ultimately that ends up being worth it over the cleaner sound of CD. Probably less than 10 percent of my listening is on vinyl, but I really do appreciate that 10 percent.

 

[milosz]

There are people who believe that vinyl, being analog, is inherently better than digital because it doesn't chop the audio into samples. There's plenty of math to show that this is a fallacy, but demonstrable truth seems to have lost it's value these days.

I have no doubt that there are quite a few who LIKE the coloration inevitably introduced by vinyl playback. I believe that many vinylphiles also like the things that have to be done to recordings during mastering of an LP: certain EQ curves have to applied at certain points in the recording to prevent groove amplitude from being too high, both in terms of keeping the stylus from jumping out of the groove and also in terms of fitting enough audio on an LP side. There's also reduction of dynamic range during LP mastering to fit within the antique S/N profile of a record. Track mix might also be different in a recording on a vinyl platter than a digital form- to bring certain things out that would be otherwise buried by noise and distortion.

And let's not neglect considering the impact that nostalgia has on audio preference. I remember listening to my first Mississippi Fred McDowell LP back in the 1960's, and the veil of hiss and light crackling is part of that memory. I'm not the only one with memories of vinyl music, and I think to many vinylphiles this distorted sound that is nearly buried by noise seems "right" or "musical."

Then you take propaganda- Michael Fremer says vinyl beats digital (he is waiting for digital to disappear; he once asked the head of Rega why he was "still making CD players") and he has followers. Never mind that most LPs are made from digital studio recordings these days, he says vinyl is better and his subjective edict is taken as "proof" by those incapable of critical analysis and without understanding of how human sound perception actually works. The same people who "don't believe" in blind listening tests.

And there is a certain amount of conspiracy aficionado in many analog diehards. There is a belief that the record industry invented digital not as a better way of storing and playing back music, but as a cynical tactic to get everyone to abandon their LP collections and buy new copies of everything on CD. Thus, digital was likely part of the sinister plot by evil illuminati to establish a new world order.

To be fair, there is much that is enjoyable about vinyl. The albums are nice objects, the ritual of carefully sliding one from it's sleeve, reverently placing it on the turntable, cleaning it, placing the arm for playback- all for a mere 20 minutes of music- there is an appeal to this, almost scratching an OCD itch in some sense. Big fancy expensive turntables are amazing to see, spending huge sums on turntables, arms, motor power supplies, expensive cartridges made from unicorn hooves, over-the-top phono stages - it's all impressive. A Mississippi Fred McDowell record spinning on my VPI Scout is much more interesting to see than a FLAC file playing off my NAS. Playing a record is a more intentional, in-the-moment act than starting digital playback with a click or button push. napilopez is absolutely right about the almost yogic cognitive experience that listening to a record entails.

And there is no denying that good music is good music, whether on a vinyl slab or being routed along thousands of miles of fiber optic cable as an Internet stream.

Finally, when you consider the Rube Goldberg process that is carried out to go from a recording made in a studio or concert hall to a shrink-wrapped LP in a shop, it is a wonder it doesn't sound even worse.

 

[KMN]

@amirm Do you have other choices for generator output impedances (you used 20R) closer to a typical MM and MC cartridge respectively?

Since most electronics can out perform, noise wise, the noise output of moving magnet cartridges, testing at typical moving magnet cartridge impedance would swamp the measurement with thermal noise. If you swamp the measurement with thermal noise, greater than the electronics noise , how can you compare the performance of one manufacturers preamp to another?. Low Rs is obviously not representative of the real world but at least it you to see the difference between the electronics.

 

[Labjr]

"Budget phono stage?"

Topping: "Hold my beer!"

 

[hello_there]

seeing these measurements, I have a question:

could vinyl be better that cd audio in any way?

all I can think of is that for example there are vinyl rips with wider frequency range (with sound over 22khz).

are there any other vinyl benefits considering most phono preamps seem to have worse performance that an average DACs (in terms of SINAD at least)?

I imagine that the mastering of the CD and LP of the same title may differ greatly, and different releases of the same CD title may have different mastering. This could be a valid reason to prefer a particular LP (or LP rip) over a CD of the same title.

It's reasonable and understandable to assume that a recording with a preferred mastering might be more pleasurable to listen to, even if the SINAD suffered.

While I don't really listen to AC/DC all that much, I have a digital copy of a Robert Ludwig mastered LP of Back in Black. The sound is phenomenal. Is it objectively better than a CD? Don't know. I do know it sounds absolutely perfect and incredibly balanced and better than any other version I have ever listened to. Sometimes I will listen to a track just to hear such well recorded, perfectly balanced sound. And I've been 'over' AC/DC for years.

 

[fricc]

No. And I still have >1000 LPs and an expensive TT.

It is complicated.
From the fidelity point of view, vinyl has no advantage whatsoever, noise is high, dynamic range is limited, and even the best cartridges have tons of resonances and distortion (10%-15% in treble is norm). Anything above 18kHz is usually pure harmonic distortion.
What makes the difference is the mastering.
Modern (say, after 2005) digital recordings are in most cases pretty good, but the early digital "remasters" (1990s-2000s) of older records can be quite poor: often they're sloppy jobs, with tons of compression and equalization that doesn't sound that great. Or maybe they sound really flat (see early Beatles CD reissues).
Take for instance the case of the various CD reissues of Pink Floyd's The Dark Side of The Moon, there is lots of them, the one that sounds OK if the Toshiba Black Triangle (very rare, go find one), most others are quite atrocious. If you own the original LP you will find it better sounding than most CD renditions. The SACD HD remix is nice, but the CD version has lots of clipping. This is just a notable example. It took over 30 years (2009) to get the Beatles CDs to sound right.
"Modern" vinyl reissues are often kind of pointless, but sometimes they provide an alternative mastering that is less bright and compressed and it can sounds much better than the CD counterpart (Muse's The Resistance is a good example, and Madonna's Ray of Light LP is awesome). I have had many bad experiences with modern LP pressings though (lots of surface noise and crackling), IMHO they have much lower quality than the average 70s-80s pressings.

 

[SegaCD]

I’ve never understood the attraction of Vinyl. If you want to have a physical collection, why not buy CDs? Do people really enjoy all that noise by calling it warmth?

Besides the physical fun/art of it all, I have a vinyl (& general analog audio) collection for two reasons:

1. I like analog recordings in to remain in the analog domain. If this website has taught us anything, it's that there are lots of inherent problems with audiophile/studio grade electronics that a lot of folks will argue for to their grave. If you have a analog master that was converted to digital, you'd better hope that the ADC was well designed and hope the engineer in charge of the transfer knew what he was doing and that he didn't screw up the transfer. What are the quality of the original masters the digital copy came from? Are there drop-outs that required interpolation? There are a lot of unknowns when it comes to the digital conversion process that is abstracted out. Is it EQ'd? Loudness-war-ed? That's why you see a lot of debates (like on the Steve Hoffman forums) on not only the quality of a recording themselves but between each release/remaster. Of course, whether or not these issues override the issues between vinyl pressings, analog noise floor, your own system's inherent flaws, etc is debatable but it gets you closer to how the recording was when it was fresh. (On a side note, I miss the early days of CDs and how they had the SPARS code system; much easier to figure these things out.)
2. There are a lot...and I mean A LOT of music that was never rereleased digitally. I have a decent amount of music from nearly all eras that were never rereleased on other formats...and don't get me started on some of the weird and wonderful things that are mostly forgotten and unique to the analog days. Two such examples are the whole (matrix & CD-4) quadraphonic fiasco & multisided records.

 

[Vuki]

I’ve never understood the attraction of Vinyl. If you want to have a physical collection, why not buy CDs? Do people really enjoy all that noise by calling it warmth?

Thera are (still alive) people who were collecting music before cd era.

 

[Deleted member 2348]

Low Rs is obviously not representative of the real world but at least it you to see the difference between the electronics.

No. It hides potential differences. See #17 and #18. For MM inputs these low Rs measurements are meaningless.

To make things (hopefully …) a bit clearer I made a quick and dirty noise simulation with LTSpice and the two OP amps I mentioned earlier (AD797 and NE5534). AD797 has very low voltage noise (~1nV/sqrt(Hz) and relatively high (2pA/sqrt(Hz) current noise. NE5534 (which, by the way, is used in the Parasound Zphono if I read the photos on the net correctly) has reasonably low voltage noise (~3.5nV/sqrt(Hz) and reasonably low current noise (0.4pA/sqrt(Hz)). For the sake of simplicity I simulated a linear amplifier with a gain of +40dB (100) and 5mV input voltage.

In the image attached you see (from left to right):

Summary:
In this test AD797 is much better than the NE5534 a low source impedance.
With a real world (MM-like) source impedance the result is reversed and the NE5534 is better than the AD797.

You can do the same test with the standard 47k input resistor of MM inputs:

Here the results are:

(1) AD797 with a source resistance of 20 ohms. SNR (unweighted, 20Hz … 20kHz) is excellent at 88dB.
(2) AD797 with a typical MM as source impedance (500 ohms, 0.5H): SNR is low at 53.3dB.
(3) NE5534 with a source resistance of 20 ohms. SNR is very good at 74.7dB.
(4) NE5534 with a typical MM as source impedance: SNR is good at 62.1dB. That's more than 4dB worse than without the 47k resistor!

Again the MM source impedance reverses the result obtained with the 20 ohms source.

 

[restorer-john]

No. It hides potential differences. See #17 and #18. For MM inputs these low Rs measurements are meaningless.

To make things (hopefully …) a bit clearer I made a quick and dirty noise simulation with LTSpice and the two OP amps I mentioned earlier (AD797 and NE5534). AD797 has very low voltage noise (~1nV/sqrt(Hz) and relatively high (2pA/sqrt(Hz) current noise. NE5534 (which, by the way, is used in the Parasound Zphono if I read the photos on the net correctly) has reasonably low voltage noise (~3.5nV/sqrt(Hz) and reasonably low current noise (0.4pA/sqrt(Hz)). For the sake of simplicity I simulated a linear amplifier with a gain of +40dB (100) and 5mV input voltage.

In the image attached you see (from left to right):


View attachment 82096

Summary:
In this test AD797 is much better than the NE5534 a low source impedance.
With a real world (MM-like) source impedance the result is reversed and the NE5534 is better than the AD797.

You can do the same test with the standard 47k input resistor of MM inputs:

View attachment 82098

Here the results are:

(1) AD797 with a source resistance of 20 ohms. SNR (unweighted, 20Hz … 20kHz) is excellent at 88dB.
(2) AD797 with a typical MM as source impedance (500 ohms, 0.5H): SNR is low at 53.3dB.
(3) NE5534 with a source resistance of 20 ohms. SNR is very good at 74.7dB.
(4) NE5534 with a typical MM as source impedance: SNR is good at 62.1dB. That's more than 4dB worse than without the 47k resistor!

Again the MM source impedance reverses the result with the 20 ohms source.

In the real world however, you are most likely to have a MC stage up front, followed by an MM w/RIAA stage, with each optimised to suit their respective input impedances and overall expected levels. They are switchable & often simply series cascaded for MC. It's rare to see a dedicated MC stage right through to line/tape out level without leveraging the MM stage with RIAA.

How often is a single opamp used for MC with RIAA in the NFB loop? Can't say I've seen one in a successful commercial product. You'd be looking for ~60dB for 100uV LOMC in any case.

 

[analogSurviver]

seeing these measurements, I have a question:

could vinyl be better that cd audio in any way?

all I can think of is that for example there are vinyl rips with wider frequency range (with sound over 22khz).

are there any other vinyl benefits considering most phono preamps seem to have worse performance that an average DACs (in terms of SINAD at least)?

The prime reason why analog record will forever remain superior to CD is frequency response.
The frequency response of analog records is flat to approx 25-27kHz ( depending on the cutterhead used ) when analog master disc is cut in real time. It is NOT brickwall filtered above that frequency as most PCM is. When less than real time speed for analog master disc cutting is used, that frequency gets correspondingly up - for half speed mastering that means 50-54kHz flat response. That exceeds whatever is possible with 96 kHz sampling - as far as frequency response fidelity is concerned.
There are - unfortunately WERE - phono cartridges capable of essentially flat response up to 50 kHz; all while staying within reasonably affordable price limits.
In that sense, the last 40 or so years have been the opposite of progress.

Analog records can be better than anything digital - with the only possible exception being latest gen ADC/DACs with sampling frequency of at least in 350 kHz range and above. The only well documented and verified by a third party digital device capable of such performance is to my knowledge RME ADI-2 Pro FS.
The reason for the above is quite simple. It is the quantization noise above 20 kHz in digital. Unless the digital is advanced enough not to introduce any noise/artefacts that exceed say -100dB UP TO WHATEVER THE HIGHEST FREQUENCY that digital device can have any measurable output. In direct comparison while making a digital recording of analog record, I have yet to hear/see one that does not introduce some additional noise above 20 kHz that manages to become audible.
And, unfortunately, I have yet to try the RME menioned above.

For that reason, I would like to see measurements of digital gear up to and beyond frequency any meaningful output from DUT. Essentially almost perfect ( and certainly inaudible ) performance just to 20 kHz is totally and utterly meaningless - if it is allowed to misbehave above 20 kHz at anything exceeding approx -100 dB.

 

[analogSurviver]

Regarding the overall noise of phono playback devices I guess the present method of testing is not good enough to represent the real world results well enough.

Above are great posts regarding the noise of various phono input configurations. Not much meaningful to be added.

Back in the day analog was the only game in town, the S/N figures obtainable in above posts have been deemed as sufficient. But, given that digital kept ever improving, S/N figures from back in the day seem today to be lacking.

Today, amplifiers can well have whatever the noise they introduce well below the noise of the signal source - that is to say below the thermal noise of the transducer. And the only way to reduce that thermal noise is by reducing the impedance of the transducer.

I will illustrate this with two MC cartridges coupled to the MM input level phono input using step up transformer ( SUT in further text ).

#1: Denon DL-103 40 ohms DCR, L low enough to be next to insignificant as far as noise is concerned, output voltage 0.3mV

Idealy, a 40 ohm input resistance/impedance SUT should be used. SUT will not transform only the voltage, but also the impedance as seen by the MM phono input. And, the output impedance of SUT will be input imedance SQUARED - and that brings 1600 ohm - a VERY high impedance, decreasing the S/N of whatever MM input used considerably.

#2 Benz TR 1 ohm DCR, L low enough to be insignificant as to noise, output 0.1 mV

Ideally, a 1 ohm resistance/impedance SUT should be used. And since output resistance/impedance squared will remain 1 ohm, that is what the MM input will see - allowing S/N almost equal to the short circuited input !

We could nitpick about exact voltages, step up ratios, MMphono preamp noise, etc - but the net effect will always remain the same; at least 20 dB better S/N in case #2 than in #1. Or, in other words, noise ceases to be a factor for all practical purposes.

Carts have progressed in this direction even further - BELOW 1 ohm impedance. And when paired by the appropriate current preamp, can have crazy high S/N without having to use SUTs. At the time, Haniwa ( 0.4 ohms, 0.3uH ) seems to be on this frontier; at a cost...

 

[lloyd84]

I'd be very interested to see measurements for one of their "Halo" amps. They're one of the only products I've ever seen get a poor review in the big glossy hifi mags.

 

[renaudrenaud]

I’ve never understood the attraction of Vinyl. If you want to have a physical collection, why not buy CDs? Do people really enjoy all that noise by calling it warmth?

Why people smoke? It's dangerous for your health, it smells, expansive... We are not always doing things just responding to pure logic.

 

[restorer-john]

The prime reason why analog record will forever remain superior to CD is frequency response.

The frequency response of digital is ruler flat from DC to fs/2. It is, essentially, a straight line.

There is no cartridge and RIAA stage combination on earth, that is remotely as flat as even 16/44 digital's frequency response. Not only that, each time you play that magical test record that extends up to 50KHz, it wears, and after maybe 10 plays or less, you can forget 50KHz. You can forget 20KHz also, that test track lasts a few plays.

If you want to talk upper limits, sure, a few cartridges could/can hit 50KHz with the right (Denon) test record, in the right circumstances with a phono stage that extends the RIAA curve out to 100KHz (they are rare) and you'll get a response, but frequency limits and deviation from linearity are two different things.

I'm with you in terms of extending the response over 20KHz to get flat response in the audible bandwidth where analogue is concerned, but how far do you go? I (and many others) have amplifers that will hit 500KHz. Is that necessary and what problems does it bring, rather than solve? Do we just revel in the perfect square wave because we can?

We have Class D aficionados extolling in band performance that is flawless, and out of band performance they dont want to talk about. Then we have gurus of the wide bandwidth school where 150KHz is a bare minimum for an entry ticket to the audiophile playground. And we have the guys rooted in what can be heard with human ears and are happy to roll-off the bottom and high end.

It's all about what makes you happy, in your loungeroom, your listening room, or your purpose built, acoustically treated and ridiculously expensive man-cave. It's not what someone else tells you is good, bad or indifferent.

 

[Wombat]

This article covers the possible extended HF performance of vinyl recordings vs CDs. In reality it is unlikely to be an advantage due to practical limitations in the properties of vinyl, production, manufacture and reproduction. Certainly not enough to outweigh the inherent shortcomings of the medium compared to CDs.

https://www.creativeaudioworks.com/2012/02/the-myths-and-reality-of-vinyl-records-vs-cds/

SACD and DVD-A make the pro-LP frequency range argument redundant.

 

[LTig]

Regarding the overall noise of phono playback devices I guess the present method of testing is not good enough to represent the real world results well enough.

Above are great posts regarding the noise of various phono input configurations. Not much meaningful to be added.

Back in the day analog was the only game in town, the S/N figures obtainable in above posts have been deemed as sufficient. But, given that digital kept ever improving, S/N figures from back in the day seem today to be lacking.

Today, amplifiers can well have whatever the noise they introduce well below the noise of the signal source - that is to say below the thermal noise of the transducer. And the only way to reduce that thermal noise is by reducing the impedance of the transducer.

I will illustrate this with two MC cartridges coupled to the MM input level phono input using step up transformer ( SUT in further text ).

#1: Denon DL-103 40 ohms DCR, L low enough to be next to insignificant as far as noise is concerned, output voltage 0.3mV

Idealy, a 40 ohm input resistance/impedance SUT should be used. SUT will not transform only the voltage, but also the impedance as seen by the MM phono input. And, the output impedance of SUT will be input imedance SQUARED - and that brings 1600 ohm - a VERY high impedance, decreasing the S/N of whatever MM input used considerably.

Nope. The input impedance is multiplied by the square of the transformation ratio. A stepup transformer 1:10 multiplies the input impedance by a factor of 100. So you're totally wrong with your 2nd example.

 

[LTig]

The prime reason why analog record will forever remain superior to CD is frequency response.
The frequency response of analog records is flat to approx 25-27kHz ( depending on the cutterhead used ) when analog master disc is cut in real time. It is NOT brickwall filtered above that frequency as most PCM is. When less than real time speed for analog master disc cutting is used, that frequency gets correspondingly up - for half speed mastering that means 50-54kHz flat response. That exceeds whatever is possible with 96 kHz sampling - as far as frequency response fidelity is concerned.
There are - unfortunately WERE - phono cartridges capable of essentially flat response up to 50 kHz; all while staying within reasonably affordable price limits.
In that sense, the last 40 or so years have been the opposite of progress.

The only reason for pickups being able to replay up to 50 kHz was the introduction of the CD4 quadro channel system, where the rear channels were multiplexed into the higher frequencies.

For stereo this was never required as very few microphones can capture significant levels above 20 kHz, neither could the analog tape recorders.