iFi Zen Phono 3 Preamplifier Review

[mike70]

Pretty good argument here for using a SUT instead of the MC gain stage.

Is what I use and what subjectively brings me a tiny difference in favour of MC.
With a standard preamp in MC setting, I can't appreciate any real improvement.

 

[Angsty]

I used to have a Sutherland Insight which I really liked as an upgrade to a Parasound Zphono. Used a Hana SL on it. But when I went to a Bryston phono with an integrated SUT, I didn’t look back.

There can be something different that a SUT adds to the mix versus simply increasing op amp gain.

The problem is that adding a quality SUT to a iFi Zen may not be competitive in total cost and performance to a dedicated MC phono like the MC Pro.

 

[mike70]

I used to have a Sutherland Insight which I really liked as an upgrade to a Parasound Zphono. Used a Hana SL on it. But when I went to a Bryston phono with an integrated SUT, I didn’t look back.

There can be something different that a SUT adds to the mix versus simply increasing op amp gain.

The problem is that adding a quality SUT to a iFi Zen may not be competitive in total cost and performance to a dedicated MC phono like the MC Pro.

If you only use MC, I agree 100% ... but if you use MM and MC (as I do), then a sut and MM pre is the right choice (in my opinion)

 

[musicforcities]

Why would one buy this when the Schiit mani 2 has far better Sinaid and costs less? I believe it even has MC capabilities. Am I missing something?

 

[Bob from Florida]

Why would one buy this when the Schiit mani 2 has far better Sinaid and costs less? I believe it even has MC capabilities. Am I missing something?

Take a look at the below graphs. The Zen’s 60,120, & 180 HZ humps are well masked by the noise baseline, the Mani 2’s 60,120, & 180 HZ humps stand out. During quiet passages at higher volume settings you may hear hum on the Mani that is masked on the Zen. That is the primary issue in my view, most likely the result of the power supply in the Mani.

 

[Sean_S]

I'm surprised at the amount of views of this review. I couldn't care less about phonograph playback.

 

[mike70]

I'm surprised at the amount of views of this review. I couldn't care less about phonograph playback.

if you post that only to show your feelings ... listen to digital and forget about it.
if you post that waiting for some comment, i can say that vinyl is the blockbuster in physical media, so i don't understand your opinion properly ... unless you think your point of view must be valid for everyone else.

 

[Bob from Florida]

if you post that only to show your feelings ... listen to digital and forget about it.
if you post that waiting for some comment, i can say that vinyl is the blockbuster in physical media, so i don't understand your opinion properly ... unless you think your point of view must be valid for everyone else.

Please don't feed the trolls.

 

[musicforcities]

Take a look at the below graphs. The Zen’s 60,120, & 180 HZ humps are well masked by the noise baseline, the Mani 2’s 60,120, & 180 HZ humps stand out. During quiet passages at higher volume settings you may hear hum on the Mani that is masked on the Zen. That is the primary issue in my view, most likely the result of the power supply in the Mani.

View attachment 400451View attachment 400452

Thanks! That is very helpful. I am just learning about the specifics of phono preamps in the ASR way and am a bit lost among the reviews. Pity about the Schiit noise.

I have an old Thorens TD 126 mkii I use occasionally…and I mean seldom…and have been thinking about getting a new phone pre. I had an old Cambridge audio MM phono stage (not the solo or duo, an older model) ) but its electrolytic caps are shot (one filter cap actually blew up… on a phono amp!) and I suspect this caused other issues. right now I am just using the phono stage on a Yamaha AVR. Which works fine I guess. The turntable with a portion 2m red or Denon dl-110 sounds closer than I would expect to a cd or cd quality streamed music through the same avr. Which I guess means it either is a good phono stage OR the AVRs performance limitations (ADC, DAC) and processing sort of evens out the performance of everything passed through it. lol.

(Yeah don’t get me started on using the pure direct setting…I have never had an avr that sounded right without serious eq and room correction.)

 

[musicforcities]

I am still waiting for an ASR analysis of actual LP playback SINAD. If Amirm needs a test LP with test tones on it, I will send him one, just let me know.

I'm surprised at the amount of views of this review. I couldn't care less about phonograph playback.

I’m not. For those with a vinyl collection for some reason, it is not all that easy to find proper objective testing of phono stages. especially if it’s either ones passion OR like me, a very occasional use/indulgence so I want decent performance at a reasonable price.

 

[mike70]

Please don't feed the trolls.

You're right, I'm sorry

 

[ryanmh1]

I'm not entirely convinced I've got this figured out right yet on high frequencies. When they refer to high frequency overload margins in decibels, should that or should that not include RIAA? This goes on to say that 28dB is desirable in the audio band, rising to 36dB ultrasonic. That just doesn't make sense at all if you calculate the required margin in dB after tending to RIAA. @sergeackland went on to say in that thread that, "with, say, a 20dB overload margin at 1kHz, that should be near enough 40dB at 20kHz". Well, that's just how Soundstage was specifying it in decibels, so maybe they are right to do that after all.

So, I have to think they're suggesting 16dB in the ultrasonic region (subtracting out the 20dB RIAA), when measured as ASR measures it. I think this must be the right answer, since maintaining 38dB at ultrasonic would otherwise be impossible. If we call 20kHz "ultrasonic", this is only 31mV at 20kHz as ASR measures it, since the RIAA curve is applied (310mV off the cartridge). If we call 20kHz "audio band" it's an itty bitty 12mV (which I believe is still 120 off the cartridge). If so, that would put overload requirements much lower, and a lot of these declines wouldn't be very concerning at all. The performance would actually be just fine.

That said, almost nothing but the iFi Zen that has been measured actually hits this quite optimistic 28dB at 1kHz, ref 5mV. So, I'm more impressed with this than I was. I think. I hate pre-emphasis curves.

tl;dr: Thsi was bugging me a bit, so I sat down and figured it out a bit better. Since the measurements here are with preemphasis, you're going to be looking for 70mV or more at 1kHZ and 10kHz, and 50mV at 20kHz, and have no concerns about any record you ought to be playing. Less than this is also almost certainly perfectly fine at 20kHz, particularly if the DUT doesn't latch or start spewing IMD on clicks. That the numbers decline is not problematic in and of itself, but rather a symptom of how the RIAA preemphasis was done. They just can't decline too much. By any reasonable measure, the Zen is probably fine, and should play any reasonable record without overloading.

More:

I'm going to have to stand partially corrected on my first post, and note that the above is closer to correct, but not quite there. I think in the quote above they may have been mixing terms, and actually shooting for 28dB at audio, and 16dB ultrasonic. I don't really know what to make of it. If they were actually calling for a higher margin at ultrasonic frequencies, there doesn't appear to have been much if any justification given for it in the passage. Who knows. I can't reason why that would make sense for a moving magnet cartridge or actual records at all, given how they work and how they are recorded. And so far as I can tell, no one has ever bothered to decode the spectral content of a record click or pop. Except, it seems we ought to be able to take studies of "content recorded from records" as a decent guide, since they had to get that off a record with a phono cartridge. And those don't show huge 20kHz pulses. In any event, we can derive targets from those who have at least done some study here and put it more plainly.

The discussion is wide ranging, but there's a good overload discussion here: https://www.audiosciencereview.com/.../phono-preamp-headroom-why.56265/post-2062371. According to Michael Fidler in the linked post, "Based on my own experience and various articles I've read upon the subject, it's my view that overload margin should be at least 10 times the nominal cartridge output level, preferably plus 3dB all the way to 23dB or so. I aim for at least 75mV at 1kHz, and 350mV at 10kHz in my own MM designs, and make sure that no further HF constraints appear against an RIAA-pre-emphasised signal appear until at least 25kHz." That's not unreasonable, albeit quite conservative.

Now, this get's really confusing due to the pre-emphasis curve. So 75mV at 1kHz is indeed just that, since the preemphasis is zero. At 10kHz, we have preemphasis of about 14dB, 20dB margin, then add 3dB, so we get the 350mV referenced as Michael Fidler says is ideal (38dB over input). Knock the preemphasis back out, and you're at about (ta-da!) 70mV as ASR measures it. The Zen delivers it all, and them some. At the more standard "20 dB" margin, instead of 23dB, you need 251mV, or as ASR would measure it and most would recommend, 50mV. But it's debatable whether this is really enough. Sufficient margin at 10kHz is arguable more important than 20kHz for reproducing music. 70mV is a reasonable target.

At 20kHz, again it's not so clear what margin you really need. Recorded content is diminishing (even after accounting for preemphasis) and I haven't been able to find good spectral analysis of pops and clicks. Just summartions of the content that comes off a records, and I have no idea how you would get it off the records without pops and clicks, nor do I know how, when they did this 50 years ago, they would have isolated and eliminated them (or why they would have done that). If you want to be ultraconservative, we take the 20dB preemphasis, add 23dB, and shoot for 710mV, or (ta-da!, again) about 70mV as measured at ASR. Let's call that "Exemplary". But it does seem rather unlikely according to most sources that you need that. Even 20dB ought to be well more than enough for any reasonable recording, so you're once again back at 50mV, and even that is probably more than enough. Let's call that "Great". Odd are, 40mV will probably do just fine. Let's call that "Good". Anything under 30mV I would call "Unacceptable". With a little leeway to permit just over 1% THD, Zen hits Great. Let's call it a Good+. Technically, it seems possible it might clip on the hottest thing you could throw at it., at which point its overload behavior becomes important.

In the course of trying to sort through this, another concern came up: Overload behavior at low frequencies. There's a good paper from Tom Holman circa 1977 that goes into good detail about this, discussed in another thread here. Basically, you also need sufficient margin there and also low cut (particularly in these opamp based designs) to avoid speaker pulsing and IMD at the speakers. That's a brutal oversimpliciation, but oh well. How well iFI's dynamic or intelligent low cut works is less than clear. So, I'm back to the Precision Phono being a safer bet. Sorry, iFi. Show how the magic works or lose my money. That low end issue is also enough to convince me the preamp in my Denon won't cut it, despite the perfectly fine overload margins.

All the separate threads about measurements and what is necessary are well and good, and very interesting. What's important to me, though, is relating that to what is actually measured so it can be better understood whether a particular products has any potential strengths or weaknesses. "20db" doesn't mean anything, if you don't relate it to how the devices are being measured. Hopefully this helps a bit.

 

[NielsMayer]

It's too bad they didn't just make a cheaper, balanced, single-eq-curve version of this https://www.amazon.com/iFi-Phonostage-Preamplifier-Compatible-Cartridges/dp/B088SSSTPD/
"iFi Micro iPhono3 Black Label Phonostage/Preamplifier Compatible with MM and MC Cartridges - Turntable/Home Theater System Audio Upgrade"
From year 2020 at $999.00, currently on sale at -20^ at $799.00

NB: claims to have a 84dB S/N and has a much more useful shape/size

 

[lini]

(...) Now, this get's really confusing due to the pre-emphasis curve. (...)

Might make sense to use Shure's old study result graph as orientation, which they've published in their technical seminar paper - and of which you can see a variant with improved scaling over there: https://pspatialaudio.com/shure velocities_enhanced.png. In that study they've checked quite a lot of records for actual peak velocities, represented by those dots/little circles in that graph. So according to that, worst case peak velocities would appear to be roundabout 50 to 55 cm/s in the region between roundabout 5 and 20 kHz.

For cartridges, that are designed for MM inputs, we can assume a transmission factor range of roundabout between 0.5 and 2.2 mV(eff.) per cm/s (peak) - so with the aformentioned actual peak velocities that would translate to phono stage input voltages of roundabout 27.5 to 121 mV(eff.). If we now assume a medium high gain of factor 100 (or respectively 40 dB), we can see, that this would get problematic, if we'd use opamp-based linear amplification, followed by passive RIAA-(re-)EQ, as in combination with a "loud" DJ cart with 2.2 mV per cm/s (like for example an Ortofon Q.Bert) the opamp would have to provide an output voltage up to 12,1 V(eff.) or respecitvely a tad over +/- 17.1 V(peak). So, assuming a typical phono stage model with an internal supply voltage of ca. +/- 15 V symmetrical, that approach won't work. Whereas if we'd reduce the level by (-) 6 dB, for example by either using a more regular cartridge with ca. 1 mV(eff.) per cm/s or by lowering the gain to a more conservative factor 50 (ca. 34 dB), that should work.

Would be good, if the phono stage would be also be able to cope with "loud" carts, though - and at the same time we might not want to lower the gain, in order not to produce an all too weak output voltage in combination with typical records, not so loud cartridges and some modern receivers and integrated amps with somewhat insensitive line-level inputs (like for example the Yamaha A-S201 and R-S202 or the Sony STR-DH190, all of which having a line-level input sensitivity of 500 mV). Hence one can understand the popularity of "the usual Lipshitz style approach", being supposed to mean a single-stage, opamp-based implementation with the RIAA-(re-)EQ being done in the negative feedback loop - so that the amplification isn't linear anymore, but frequency-dependent instead.

Greetings from Munich!

Manfred / lini


P.S.: Oh, and hello ASR community, btw!


edit: Post scriptum added.

 

[ryanmh1]

Might make sense to use Shure's old study result graph as orientation, which they've published in their technical seminar paper - and of which you can see a variant with improved scaling over there: https://pspatialaudio.com/shure velocities_enhanced.png. In that study they've checked quite a lot of records for actual peak velocities, represented by those dots/little circles in that graph. So according to that, worst case peak velocities would appear to be roundabout 50 to 55 cm/s in the region between roundabout 5 and 20 kHz.

For cartridges, that are designed for MM inputs, we can assume a transmission factor range of roundabout between 0.5 and 2.2 mV(eff.) per cm/s (peak) - so with the aformentioned actual peak velocities that would translate to phono stage input voltages of roundabout 27.5 to 121 mV(eff.). If we now assume a medium high gain of factor 100 (or respectively 40 dB), we can see, that this would get problematic, if we'd use opamp-based linear amplification, followed by passive RIAA-(re-)EQ, as in combination with a "loud" DJ cart with 2.2 mV per cm/s (like for example an Ortofon Q.Bert) the opamp would have to provide an output voltage up to 12,1 V(eff.) or respecitvely a tad over +/- 17.1 V(peak). So, assuming a typical phono stage model with an internal supply voltage of ca. +/- 15 V symmetrical, that approach won't work. Whereas if we'd reduce the level by (-) 6 dB, for example by either using a more regular cartridge with ca. 1 mV(eff.) per cm/s or by lowering the gain to a more conservative factor 50 (ca. 34 dB), that should work.

Would be good, if the phono stage would be also be able to cope with "loud" carts, though - and at the same time we might not want to lower the gain, in order not to produce an all too weak output voltage in combination with typical records, not so loud cartridges and some modern receivers and integrated amps with somewhat insensitive line-level inputs (like for example the Yamaha A-S201 and R-S202 or the Sony STR-DH190, all of which having a line-level input sensitivity of 500 mV). Hence one can understand the popularity of "the usual Lipshitz style approach", being supposed to mean a single-stage, opamp-based implementation with the RIAA-(re-)EQ being done in the negative feedback loop - so that the amplification isn't linear anymore, but frequency-dependent instead.

Greetings from Munich!

Manfred / lini


P.S.: Oh, and hello ASR community, btw!


edit: Post scriptum added.

The Shure chart was one of the references I ended up using. The highest velocity, I believe, is actually around 8kHz. It drops somewhat after that. The real question is whether that includes clicks and pops. If it does, it's quite possible you need slightly less margin at 20kHz. With the usual closer to 1mv per cm/s an audiophile cart is likely to put out, it would seem you rarely need a full 20dB margin, and possibly never at 20kHz which would explain how a lot of high end phono stages get away with less than "ideal" margins.

To really nail it down, we would need to analyze what happens on a modern opamp stage on a bad scratch.

 

[lini]

(...) The real question is whether that includes clicks and pops. (...)

Rather not, I'd assume - as the interest behind the study probably was to determine, what a good cartridge should be able to properly track. So I think, that they were only interested in intended signals/actual content rather random, spurious signals.

Which of course might lead us to the question, which extra margin would seem appropriate to also cover unintended signals, caused by scratches, dirt or whatever. That might be a somewhat arbritrary choice. For example, should that margin also include mishaps, like a hard tonearm drop?

Greetings from Munich!

Manfred / lini

 

[Genpattonj]

Interesting review (Thanks Amir) for a multitasking phono preamp. I particularly like the RIAA correction and the sufficient noise performance in MM mode. The headroom is acceptable for an entry/mid-range camera. The inclusion of a subsonic filter is a good idea but it seems too slow. On the other hand, on MC cartridges, the noise penalty is too high. In fact, it should be reserved for MM cartridges (or even high-level MC?). The brand would benefit from offering a phono stage dedicated to MC cartridges, provided that it seriously improves the noise performance.

I’m hoping my reply here gets a response and I’m doing this correctly. “Shrugs and hopes he’s not pi&$ing anyone off” I’ve been looking for a preamp for my Teac TN-3B-SE Turntable. I live in Vancouver and I’m vacillating between these two: Ifi Zen Phono 3 as discussed here, or the Cambridge Audio Duo.
The Zen is $400.00 Canadian. “20 bucks US” ;-) and the Cambridge I can pick up for about $470.00 Canadian.
To recap, I have a Teac TN-3B-SE turntable with an Audio Technica VM750SH moving magnet cartirdge. I do have an Ifi Pro ICAN Signature preamp/headphone amp. It has balanced input but based on Amir’s review that doesn’t seem to make much of a difference in the Zen. I was also going for the Schiit Mani2, however these two seem to do better.
So suggestions for either the Cambridge or the Zen would be much appreciated. I think there very similar in spec other than the Cambridge has a headphone out. Not a deal breaker for me.
Appreciate any feedback, suggestions.

Signed…newbie and confused between the two. “He points to the Zen, points to the Cambridge, repeats…”

 

[fedocable]

I was in the same conundrum, trying to decide between the Mani and the Alva Duo, and following some advices in this very post ended up getting a Spartan 15 by Michael Fidler. Unfortunately I still haven’t tried it, so I can’t give you my impressions, but the measurements and subjective reviews of his phono preamps are quite impressive. The main feature that puts it over the other two, at least on paper, is headroom -that is, less clipping, less noticeable clicks and pops, more indulgent to worn records.
Sorry if this messes up your dilemma even more, but it’s my two cents!

 

[somebodyelse]

The main feature that puts it over the other two, at least on paper, is headroom -that is, less clipping, less noticeable clicks and pops, more indulgent to worn records.

The LF crossfeed helps with warp rejection too. The Puffin and Waxwing (Derumble setting) and probably others also have this. It's a bit different to the more common high pass rumble filter. I haven't seen it mentioned for the Mani or Alva Duo.

 

[Genpattonj]

Thanks much for a couple suggestions. I’m disabled and on a fixed income so the price of the Spartan 15 at $ 670.00 plus shipping which most likely makes it around $ 700.00 is pushing it for me. Both the Alvo Duo and the IFi are on the order of hundreds of dollar less and have been reviewed by Amir. The Ifi has a subsonic filter as well. I don’t see the Sparton being reviewed by him as well. I might be wrong though.
It’s sort of between those two but if there’s something comparable? Around $450.00 or even $ 500.00 I’d be interested. In the meantime I’m going to closely look those two over again.
Has anyone purchased either of these two? Thoughts? Comments?
Thanks for responding in Advance!