Philips Fidelio S1 and S2 In-Ear Headphones

Philips Fidelio S1 ($99) & S2 ($149)
Philips is far from the first brand that comes to mind when I think "headphone Hi-Fi," but the Dutch electronics giant has been designing and manufacturing headphones since the 1960s - longer than many of its current competitors have been in business. In the past several years Philips has released some real gems, along with a few stinkers, leading up to the 2012 introduction of the Fidelio line of performance-oriented audio products.

The S1 and S2---the first in-ears to bear the Fidelio badge---are modestly-priced by flagship earphone standards, with the S1 set to retail for $99.99 and the higher-end S2 running $149.99. Such aggressive pricing indicates that Philips is serious about the portable audio market, and listening to the two sets makes it clear that they are serious about sound quality as well.


Exploded view of the Fidelio S1

The Fidelio S1 and S2 are both built around 13.5mm dynamic drivers---large for IEMs, but definitely not unheard of. Philips chose a half in-ear form factor for the earphones, a design popular with a few other IEM makers such as Japan-based Audio-Technica. This housing style places the driver enclosure in the outer ear with an angled nozzle fitting into the ear canal, and is commonly considered to sacrifice some noise isolation for the comfort of a shallow seal.

The build quality of the S1 and S2 earphones is extremely similar but whereas the S1 features a cheap-looking plastic baffle at the front and plain shells, the pricier S2 is all-metal and boasts a fancy-looking glossy finish reminiscent of ceramic earphones such as Sennheiser's $1000 IE 800. Both earphones utilize flat cables, though the one on the S2 is textured for a fancier look and feel. Both feature in-line microphones and single-button remotes for use with smartphones and tablets.

Accessories include a hard-shell carrying case and various eartips---four sets for the S1 and seven sets for the S2, including a pair of the super-comfortable Comply Ts-series foam tips. Isolation from outside noise is average and cable noise (microphonics) is very low.

All in all, the Philips S1 and S2 are well-designed, user-friendly, and have good fit and finish. There is only one component still needed to make these earphones great---sound.

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JRAudio's picture

Philips sold his consumer section including the rights for the name to Funai. What will be with the support of those products? Is this the last sold out of Philips ear- and head-phone. Who has interest in buying such products, that are already sold, without knowing about the future of it. I have heard that in the meantime, the support for Philips CD Drives and repair parts has stopped already.


Impulse's picture

I'm pretty sure Funai stated they wanted to continue operating most divisions, otherwise they wouldn't have signed a contract for the rights to use the Philips brands (with the option to renew it no less). Where'd you read about them discontinuing support for certain products? Not doubting it, just curious.

JRAudio's picture

I know if from contacts to the manufacturing plants. They have stopped production already and you can not get any sufficient numbers of their CD drives or any spare parts. And this was all of a sudden.


Martygord's picture

Hi JR --

On behalf of Philips I just wanted to clarify and address your comment.  Philips in the U.S. has signed a distribution agreement with Philips-Funai to distribute our Lifestyle Entertainment products – including headphones, audio products, accessories and other CE products – in the U.S.  This means that in the U.S., Philips-Funai distributes these products on Philips’ behalf and we expect this to continue in the future, with full product support.  Consumers looking for support on our products, including CD Drives, can find it at ( or by calling the general support line at 888-744-5477.


Long time listener's picture

I notice from the measurements that both of these have peaks in the treble at around 5 Khz. In my experience, this is not good, so I was surprised, given your comments about the treble quality (though I note the measurements are good in all other respects). Most IEMs--and over the ear headphones--that are typically considered to measure well, such as the Shure SE535s and the V-Sonics, tend to have broad dips here instead, followed by a rise to a peak in the 9-10Khz region. I once had a multi-armature Sony IEM that sounded quite good overall, except for a strong peak in this same region. The result was harsh, aggressive sounding treble when the music had strong content in this region (e.g., electric guitars). Do you think most people will really find the treble on these free of problems? Thanks.

ljokerl's picture

I will defer the measurement discussion to Tyll but can talk about my listening experience against the VSonics. I have a VSonic GR07BE (based on the 2nd-gen GR07) and a regular GR07 of the 1st-gen variety. The GR07s (the old one more so than the new one) sound sibilant and a little harsh to me compared to Philips. The same is true for the VSonic GR06, GR02BE, and even the new VC02 (though to a lesser extent). With a proper seal in the ear and good recordings, I don't think the treble of the Philips is problematic. 

Also, if you think that treble curve doesn't dip enough, you should see the Audio-Technica CKM500 - it's pretty much flat after compensation and the treble has this strange brittle quality despite not being harsh in the conventional sense. Very strange earphones that are nonetheless popular on Head-Fi. 

Long time listener's picture

Thanks for clearing that up. I guess because the peak at 5Khz is lower than the bass levels, and at about the same or just slightly below the midrange levels, it won't be heard as intrusive. On top of which the distortion levels are very low, which will also help. It's just that I've had bad experiences with peaks in the low treble. Tyll himself once said "Just no..." to the Sennheiser HD700 for a peak in this same region (just slightly higher actually). And there's the JVC HA-S500-Z, which measures and sounds beautiful...until you hit that peak at 7Khz, which really ruins it. So I was rightfully wary of these, but now I will likely want to give them a try.

Majestic91's picture

"The result was harsh, aggressive sounding treble when the music had strong content in this region (e.g., electric guitars)." - I've just got the S1 and I must say that this statement is 100% correct. When I listen to the music with the loud guitars or vocals the S1 starts to sound very aggresive and you can hear what can be described as the annoying "sss" noises.

Guitarist9273's picture

How do they compare to the Shure SE215, which is still up on the Wall of Fame & is exactly the same price as the Fidelio S1?

Is it just me, or do their measurements look very similar? (Though, the S1 appears to be smoother & cleaner, overall.)

By the way --- Any plans for an Innerfidelity review the newish HifiMan RE-400? Would love to see their measurements. At the same price as the S1, I'd be curious to know which one sounds better & represents a better value, in the opinions of Joker & Tyll. Had a chance to hear the RE-400 yet & form any opinions on it, Tyll?

ljokerl's picture

I thought the SE215 was worth keeping on the Wall of Fame as it does some things that the S1 doesn't - it isolates a lot, fits over-the-ear, and has detachable cables. Plus, it sounds warmer and bassier overall so it may actually work better for the average consumer. 

On the point of sound - the SE215 was a touch too warm for me while the S1/S2 are not. The treble is more present and extended but at the same time cleaner and more free of grain compared to the Shures, and the bass seems cleaner as well. I think the S1 is definitely more "Hi-Fi" overall and actually competes with the RE-400. When I compared the two I slightly preferred the S1 for bass depth and midrange clarity but was very impressed by both as far as $99 earphones go.

Regarding the RE-400 - I am not sure if Tyll is getting one from HiFiMan to measure. I can always send in mine but I would like to cover the Senn IE 800 first. It's a statement product, after all, and an interesting one. 

Three Toes of Fury's picture

It appears we headphones enthusiasts share the same thoughts....i was just about to ask the same thing as Guitarist9273,,,,S1 vs SE215.     I picked up the SE215's a few months ago per the wall-o-fame recommendation.   I like them bunches.  Sooooo i was wondering if you think the S1's are as good as, or, moreso,  substantially better?  If so i'll snag a pair. 

Thanks for the great write ups

Peace & Living in Stereo


neo's picture

These might certainly be better than the Shures, but not worth to buy a pair if you just got your Shures. Enjoy your IEMs, and most importantly your MUSIC..

The Fidelios are tempting though. I'd be curious to see how they compare to some TDK BA200s or TDK IE800?

Three Toes of Fury's picture

i appreciate the feedback, follow-up, and thoughts.    This site is a great place for open discussion and information sharing between headphone fans.

Peace & "If music be the food of love, play on;  give me excess of it"  duke orsino, shakespear, 12th Night,   1602



ljokerl's picture

Added a reply above. I do like the S1 better than the Shures but that doesn't mean you will. It also doesn't mean you should toss your new Shures and drop another $100 on the Philips. 

neo's picture

What about the TDKs mate? ClieOS seems to love them..

ljokerl's picture

on the TDKs. Maybe Tyll can get a set for us to try.

lushkin's picture

Very impressed both from the comparative view against refenrce models and the measurments. Even the isolation seems above decent for a semi-closed design.

Joker, How good you think the S1 would be as a an active heaset? Do they stay secure with wet ears?

ljokerl's picture

I suppose the more lightweight S1 could work - you would probably want to use the Comply foam tips for more secure fit. If they (the tips) are sized right for your ears, they don't slip out with sweat. 

I am not sure about the longevity of the earphones, though - they are probably not designed to cope with sweat. The housings have vents both front and rear that moisture could seep into. 

Personally I would go for a sealed-back, over-the-ear design like the Shure SE215 or the (way cheaper) MEElectronics M6. 

Impulse's picture

I had been thinking about getting custom tips for my Ety hf but now I'm pondering putting those $100 towards a pair of these instead, just for a different sound and for when I don't want/need as much isolation as the Etys provide... Although that's also what my M-80 are for. Improved long term comfort with the Etys vs new toy, decisions decisions. :p

ljokerl's picture

As an owner of custom Ety tips, I have to admit that's not an easy decision. The isolation of the FIdelios really isn't that poor, especially with the Comply tips. The M-80 still isolates less for me.

Impulse's picture

Yeah I wouldn't expect the S1 to be terrible at isolation, but it does seem like they'd be easier to take out and put on... I still have to do that whole two-hand tugging on my upper ear maneuver to get the Etys in, then again, I hear the custom tips help with that too heh...

ljokerl's picture

You still need to straighten out the ear canal when inserting custom tips, or at least I do (unless I use the supplied ear lubricant beforehand). The S1 is defintely easier to insert and remove in a hurry.

Audioaddict's picture

|Joker|, you said that the midrange clarity in the S1 compares to the RE-262. Would you say that the S1 is a good alternative if i wanted a touch more bass impact, a clear midrange, and slightly more present treble? And if you can say how does the soundstage of the two compare?? 

ljokerl's picture

That's spot on. More bass impact and more treble presence without sounding notably v-shaped. Mids are less forward than with the RE262, as expected.  

I prefer the presentation of the RE262/RE272 by a small margin - they seem to have slightly better layering. If you like wide soundstages, you'll be fine with the Philips. If you prefer more intimate/enveloping, you might miss the RE262 a bit. 

Audioaddict's picture

Thank you! i'm debating on picking up a cheaper alternative for when i dont want to worry about babying the RE-262 and for a little more fun. That and a Grado SR-80 for rock. I do like my soundstage though so i'll miss the intamacy but if it's fairly wide i should be good. The RE-262's presentation is magical the first time you hear it or try a new song. 

LuisCypher's picture

Joker, from the FR I would say that the S1 is quite bassy. However you describe the bass as just a bit enhanced. How does that match up?

Also, is the distortion at 5 kHz audible on the S1?

ljokerl's picture

It really depends on where you draw the line for calling something "bassy". The bass quantity of the Philips is similar to that of the GR07s from VSonic and I have never heard anyone complain about getting too much bass out of those - I consider them bass-enhanced but still leaning towards an accurate sound compared to most dynamic-driver earphones on the market. It is nowhere near the bass quantity of stuff like the Monster Turbine series or the Bowers&Wilkins C5, which are truly bassy (and annoying in that respect). 

The distortion was not audible to me. 

poleepkwa's picture

ljokerl, would these (fidelio S1) be a good replacement for my now defunct Phonaks Golds or are there better alternatives?

poleepkwa's picture

ljokerl, would these (fidelio S1) be a good replacement for my now defunct Phonaks Golds or are there better alternatives?

ljokerl's picture

I am not familiar with the Phonak Gold. Is that a limited edition of one of their other models? If so, which?