OLLO S5X Headphone Review

[IAtaman]

Reply from OLLO Audio.

Exploring the Target Curve Design for Spatial Audio on Headphones

Hey there! In this video, I wanted to provide some context and insights into the target curve design for spatial audio on headphones. I've noticed some interesting debates and concerns, particularly regarding harmonic distortion and the need for inspection. Our target curve was specifically...

www.loom.com

Interesting. He says in the video that they focused on spatial localization and that 1k-2k range looks a lot like the Hifiman headphones' FR in the same range as well as that of HD800S. Is that a coincidence?

On a related note, is he using MS Edge on Mac? That makes no sense

 

[Swtoby]

For Rok, quality is important and if something is really wrong he really wants to know.

This is something I think has been completely glossed over in the review. It seems clear Rok is passionate and committed to his products and not intending them to be throw away at all. Not many audio companies in my experience that really back what they sell and want the customer to be satisfied. Ollo looks to be one.

 

[Robbo99999]

I would not bother simulating the tonality of the S5X. Headphone sound (IMO) is not only tonal balance.
If that were the case we would only need to buy a HD201, EQ it to HD800 tonal balance and enjoy great sound for peanuts. It simply does not work that way.

I agree that headphone sound is not only tonal balance (measured frequency response), there's distortion measurements, the currently unmeasurable soundstage element, and also the portion above say 8kHz that can't really be accurately characterised (certainly not from Amir's measurements that are just single measurements, I'd probably use Oratory's for this exercise if he'd measured it), and also the element of unpredictable variation on different heads. But if you use a headphone for the emulation that can remove the variables of frequency response (the unit has been measured), distortion measurements (if it measures low enough at your listening levels), and removal of "unpredictable variation on different heads" (choosing a headphone that is quite predictable on different heads) then you're just left with the variables being: soundstage element, can't really be certain above 8kHz. I think when you're just left with those 2 remaining variables then you can at least ascertain if the target is any good for you, especially if it were to sound obviously wrong for instance. So I think you can gain something from the exercise, but yes you can't ever EQ one headphone to another (if they have an obviously different physical design) and expect them to be the exact same experience. However for headphones that have pretty much the same physical design, say for instance HD600/650/6XX/660S then EQ'ing one of the those headphones to another one of those headphones should work well as long as you've competently measured both units that you're comparing (as long as distortion is kept below thresholds).

EDIT: so yes, you can't turn an HD201 into an HD800.

 

[Mulder]

The OLLO S5X is a studio tool, and just like Rok says in the video @solderdude linked to, the goal has not been to create a headphone for audiophile listening experiences.

Now, however, this with headphones seems to be very personal, and I myself have realized that I am not entirely fond of headphones whose sound is based on the harman curve. For example, I have a pair of DC Aeon Closed, which is a distinct HiFi headphone, which is closer to the harman curve, but I prefer the OLLO S5X.

I therefore think it is misleading and a bad idea to describe a headphone as almost ”deficient” as a consequence of it having a different target curve than the Harman, as is the case in this review. It ought to be evaluated on it’s own merits so to say, and not for something it do not try to be. Of course, you can have harman as a reference, but when the manufacturer does not aim at this reference, in my opinion, you end up in the wrong conclusion if you do not take this under consideration. Especially as this is presented as a "flaw" that can be fixed with EQ. If you want a headphon that is based on the harman curve, you should of course not buy an OLLO S5X.

In the video, Rok also says that the distortion shown by amirms measurement is clearly an issue, and it should not be there. I think it would be good if @khensu could get in touch with Rok about this so the cause can be sorted out. (If nothing else so that @khensu will get a pair of flawless headphones, i.e. without this distortion.)

 

[khensu]

In the video, Rok also says that the distortion shown by amirms measurement is clearly an issue, and it should not be there. I think it would be good if @khensu could get in touch with Rok about this so the cause can be sorted out. (If nothing else so that @khensu will get a pair of flawless headphones, i.e. without this distortion.)

I totally agree with all you said. The S5X is just another proof point that Harman is not my preference. I get what and why it is what it is, and I’m all for it in concept.

Despite the issues measured by Amir, I still love these headphones and would be perfectly happy with them regardless. However, I will be contacting Rok and I’ll update the thread with the results.

Thanks, @solderdude for all your “priming the pump”, as it were.

 

[markanini]

I prefer something slightly different to Harman, although I do agree with the general bass to treble balance of Harman, so the stock response of this set would probably be too lean for me. It's just preference and doesn't need to be rationalized too much.

Specifically I will be annoyed If I have to track bass guitar in a recording session, wearing a bass lean headphone. That's why I'm viewing this set as being better for content enjoyment, after finding the right bass EQ. Reason enough IMO for manufacturers to swallow their pride and start standing behind providing a optional bass EQ for leans sets like this, either written out filter values in product literature, or built-in DSP on a provided digital connector.

In that way my preference is closer to to Amir, except he prefers more 3kHz than me. That brings a larger than life quality to the the playback, that's unique for headphones, but IMO it gets tiring for longer sessions, unless you want to limit your SPL.

For example, I have a pair of DC Aeon Closed, which is a distinct HiFi headphone, which is closer to the harman curve, but I prefer the OLLO S5X.

Which Specific Aeon Closed do you have? There's 3-4 different ones.

 

[Mulder]

Which Specific Aeon Closed do you have? There's 3-4 different ones.

I have the first version.

 

[markanini]

I have the first version.

The first ones weren't that Harman, A bit of a warm titled mid characteristic, similar to this Ollo.

 

[Mulder]

The first ones weren't that Harman, A bit of a warm titled mid characteristic, similar to this Ollo.
View attachment 298615

I have the DC Aeon Closed X.

 

[khensu]

(Edit: Fixed a spelling mistake)

To finally put this saga to rest, here is Rok's response about the S5X (he gave me the OK to post this):

"Hi David,

I checked your unit personally and they sound ok. Maybe slightly darker than expected. Measurements showed nothing wrong at normal volume. When boosting volume up, the harmonics start to show in the way it was explored on the forum. That happens on almost every unit. It's a harmonic distortion that comes from speaker's heavy load, acoustics bouncing of sound in the cups and vibration being transferred to the chassis. Also cross talk or basically leakage of audio out of the cups and back in. A free field measurements room should show significantly less harmonic distortion at higher volume. We only have a quiet room, not a certified free field. So we can't really measure at high volume beyond fundamental response. It shouldn't hurt the performance until getting close or above 100dbSPL. We won't continue to explore this further at this stage.

We exchanged your unit as we'd like to keep this in the lab for later, when we'll start working on updates of the model. Maybe there really is something that can be improved.

Thank you for your support.
Rok Gulič"

 

[Robbo99999]

(Edit: Fixed a spelling mistake)

To finally put this saga to rest, here is Rok's response about the S5X (he gave me the OK to post this):

"Hi David,

I checked your unit personally and they sound ok. Maybe slightly darker than expected. Measurements showed nothing wrong at normal volume. When boosting volume up, the harmonics start to show in the way it was explored on the forum. That happens on almost every unit. It's a harmonic distortion that comes from speaker's heavy load, acoustics bouncing of sound in the cups and vibration being transferred to the chassis. Also cross talk or basically leakage of audio out of the cups and back in. A free field measurements room should show significantly less harmonic distortion at higher volume. We only have a quiet room, not a certified free field. So we can't really measure at high volume beyond fundamental response. It shouldn't hurt the performance until getting close or above 100dbSPL. We won't continue to explore this further at this stage.

We exchanged your unit as we'd like to keep this in the lab for later, when we'll start working on updates of the model. Maybe there really is something that can be improved.

Thank you for your support.
Rok Gulič"

Don't know why he said the unit was measuring outside of spec earlier when he viewed Amir's measurements particularly in reference to the 230Hz distortion peak:

OLLO S5X Headphone Review

So we can clearly see that even if S4R are closed back, they have less bass than two open back construction:) Opposite than typical situation. Thats why after testing of S5x I did step back, to analise FS characteristic before testing xx numbers of HP. BTW S5x in my opinion are easier to adjust...

www.audiosciencereview.com

Because now he's saying those measurements are within spec of the product, so he's contradicted himself, not the best look.

 

[Mulder]

(Edit: Fixed a spelling mistake)

To finally put this saga to rest, here is Rok's response about the S5X (he gave me the OK to post this):

"Hi David,

I checked your unit personally and they sound ok. Maybe slightly darker than expected. Measurements showed nothing wrong at normal volume. When boosting volume up, the harmonics start to show in the way it was explored on the forum. That happens on almost every unit. It's a harmonic distortion that comes from speaker's heavy load, acoustics bouncing of sound in the cups and vibration being transferred to the chassis. Also cross talk or basically leakage of audio out of the cups and back in. A free field measurements room should show significantly less harmonic distortion at higher volume. We only have a quiet room, not a certified free field. So we can't really measure at high volume beyond fundamental response. It shouldn't hurt the performance until getting close or above 100dbSPL. We won't continue to explore this further at this stage.

We exchanged your unit as we'd like to keep this in the lab for later, when we'll start working on updates of the model. Maybe there really is something that can be improved.

Thank you for your support.
Rok Gulič"

I don’t understand this. Rok says performance would not be hurt until it reaches 100db SPL or above. But amirms measurements indicate problems as early as 94 db SPL, and clearly the performance seems to be somewhat hurt well before 100 db SPL. What is Rok saying? He says there is no problem utill about 100 db SPL, but that is also what amirms measurements show. So, if I understand Rok correctly, amrims measurements are correct, but Rok do not think this is a problem? Or do I missunderstand something compleatly?

 

[GM3]

I don’t understand this. Rok says performance would not be hurt until it reaches 100db SPL or above. But amirms measurements are at 94 db SPL, so clearly the performance is hurt well before 100 db SPL. What is Rok saying? His answer contradicts amirmns measurements, but as far as I can understand, with no explanation why. Is the difference a result of different measurement methods?

Solderdude's measurements didn't show the distortion <100dB either; measured at 90dB though:

https://diyaudioheaven.wordpress.com/headphones/measurements/ollo/s5x-1-0/

Below the distortion measurements of the S5X

(Right channel). The measurements are made at 90 dB SPL. The plot above shows the level differences between the signal (upper trace) and the harmonics. Most people prefer to see percentages instead of level differences so below the exact same plot except ‘normalized’ to the actual signal and level differences given in percentages.

Distortion levels are very low and is exemplary and rivals that of planar headphones and closed headphones. It remains distortion free even at quite loud levels.

The actual 2nd harmonic distortion may well be much lower than shown. A shortcoming of my measurement rig. Also ignore the 50Hz peak (mains hum).

vs say HFM Edition XS
https://diyaudioheaven.wordpress.com/headphones/measurements/hifiman/edition-xs-2023/

Below the distortion measurementsof the Edition XS (Left channel).

Below the same distortion plot but displayed in percentages.

The left channel also had increased distortion in the same frequency area but not same in shape and severity. Below the left channel.

There is a rise in distortion in both channels around 4kHz. This happens to be a part of the frequency range where the hearing is most sensitive. The distortion reaches over 5% which are potentially audible levels. At lower listening levels (normal listening levels are not reaching 90dB SPL at 4kHz) the distortion is lower. The higher distortion is indicative of a driver (resonance) issue though.

If you compare to Armin's, the distortion is missing, so it could be related to measuring jig, head shape, placement, etc.? Maybe 90 vs 94dB also makes a difference?

The XS isn't on ASR yet, but the Ananda is on both, and we can also see a disparity in distortion levels;
https://www.audiosciencereview.com/forum/index.php?threads/hifiman-ananda-review-headphone.22281/
https://diyaudioheaven.wordpress.com/headphones/measurements/hifiman/ananda/

I don’t understand this. Rok says performance would not be hurt until it reaches 100db SPL or above. But amirms measurements are at 94 db SPL, so clearly the performance is hurt well before 100 db SPL. What is Rok saying? His answer contradicts amirmns measurements, but as far as I can understand, with no explanation why. Is the difference a result of different measurement methods?

So up to interpretation, but don't think he's saying that at 99.99dB it will be 100% perfect, I mean, any headphone will have some distortion, and if we compare to the Edition XS above, yeah the Ollo does seem distort 1% ~200-300Hz, but others will also distort at other frequencies... I don't think it is like a glaring defect that will be easily heard; what is it, a distortion peak between about 210-260Hz? How easily audible is it? Armin: "if you have to use it without EQ in some other secondary situations, the sound is not bad.". Many online reviews haven't mentioned it either, very positive reviews... *shrug*

Another set of measurements here, which also highlights high bass distortion, which indeed increases with SPL, some comments mention that some people might hear it more than others... 90-100 is "very loud" too, so to get to Armin's 104 to 114dB.... Not sure how great the person's hearing will be if they listen to that loud music often!

Think the bottom line is; most headphones aren't perfect, if you inquired about hifiman, focal, sennheiser, etc., and confronted them with their own distortion figures, don't think you'd get very different answers; there wouldn't be massive recalls and complete redesigns, it's just how things are! YMMV is very likely the best answer here; whether you'll hear it or not, which would largely depend on the tracks and volume you're listening to.

But yeah, having read/watched quite a few posts/reviews of the S5X, people haven't really complained about this particular distortion; or mabe I just missed it... IMHO, just not that easily audible given the 'pike' and high bass frequency; maybe you could hear if it you tried, but likely not something that really jump out at you?

 

[Mulder]

Solderdude's measurements didn't show the distortion <100dB either; measured at 90dB though:

https://diyaudioheaven.wordpress.com/headphones/measurements/ollo/s5x-1-0/


vs say HFM Edition XS
https://diyaudioheaven.wordpress.com/headphones/measurements/hifiman/edition-xs-2023/


If you compare to Armin's, the distortion is missing, so it could be related to measuring jig, head shape, placement, etc.? Maybe 90 vs 94dB also makes a difference?

The XS isn't on ASR yet, but the Ananda is on both, and we can also see a disparity in distortion levels also;
https://www.audiosciencereview.com/forum/index.php?threads/hifiman-ananda-review-headphone.22281/
https://diyaudioheaven.wordpress.com/headphones/measurements/hifiman/ananda/


So up to interpretation, but don't think he's saying that at 99.99dB it will be 100% perfect, I mean, any headphone will have some distortion, and if we compare to the Edition XS above, yeah the Ollo does seem distort 1% ~200-300Hz, but others will also distort at other frequencies... I don't think it is like a glaring defect that will be easily heard; what is it, a peak between about 210-260Hz? How easily audible is it? Armin: "if you have to use it without EQ in some other secondary situations, the sound is not bad.". Many online reviews haven't mentioned it either, very positive reviews... *shrug*

Another set of measurements here, which also highlights high bass distortion, which indeed increases with SPL, some comments mention that some people might hear it more than others... 90-100 is "very loud" too, so to get to Armin's 104 to 114dB.... Not sure how great the person's hearing will be if they listen to that loud music often!

Think the bottom line is; most headphones aren't perfect, if you inquired about hifiman, focal, sennheiser, etc., and confronted them with their own distortion figures, don't think you'd get very different answers; there wouldn't be massive recalls and complete redesigns, it's just how things are! YMMV is very likely the best answer here; whether you'll hear it or not, which would largely depend on the tracks and volume you're listening to.

But yeah, having read/watched quite a few posts/reviews of the S5X, people haven't really complained about this particular distortion; or mabe I just missed it... IMHO, just not that easily audible given the 'pike' and high bass frequency; maybe you could hear if it you tried, but likely not something that really jump out at you?

Thank you for taking the time to explain this. My interpretation is, what amirm describe as a ”problem”, is not really a problem if you do not crank the volume to very high levels. I have the S5X and I have not experienced any distortion at all. But, I keep the volume at rather low levels. Over 100 db SPL for an extenden period is not a very healthy level for sure. It makes me wonder what value measurments at 104 db SPL do have from a practical point of view.

 

[khensu]

Only as a basis for comparison, I assume.

I received my new S5X today, and they sound exactly the same as the ones I sent back to Rok. I'm inclined to say that weirdness around 230Hz is inaudible at normal listening levels. I doubt I ever push beyond 85dB during most listening.

 

[Robbo99999]

Only as a basis for comparison, I assume.

I received my new S5X today, and they sound exactly the same as the ones I sent back to Rok. I'm inclined to say that weirdness around 230Hz is inaudible at normal listening levels. I doubt I ever push beyond 85dB during most listening.

If you're curious about these things, you could buy a miniDSP EARS measurement rig to measure your various headphones for things like distortion & channel matching. They cost $299. Then if so inclined you can create channel matching EQ's so that the channels are perfectly matched throughout the frequency range.

 

[IAtaman]

Thank you for taking the time to explain this. My interpretation is, what amirm describe as a ”problem”, is not really a problem if you do not crank the volume to very high levels. I have the S5X and I have not experienced any distortion at all. But, I keep the volume at rather low levels. Over 100 db SPL for an extenden period is not a very healthy level for sure. It makes me wonder what value measurments at 104 db SPL do have from a practical point of view.

If you look up equal loudness contour online, you see that 200Hz requires 12-15db higher SPL to be perceived at same loudness compared to a 1000Hz tone, and 20-25db higher compared to a 3000Hz one. My understanding is that music played at a comfortable 80db listening levels might easily have signals going above 105db for lower frequencies.

 

[Robbo99999]

If you look up equal loudness contour online, you see that 200Hz requires 12-15db higher SPL to be perceived at same loudness compared to a 1000Hz tone, and 20-25db higher compared to a 3000Hz one. My understanding is that music played at a comfortable 80db listening levels might easily have signals going above 105db for lower frequencies.

Yep, the bass in tracks is normally at a higher SPL level than the rest of the frequency range, which you can see if you spectrally analyse a few tracks. And you'll also have picks that are even higher, as when you spectrally analyse a track often the graphs are based on average trend (not peaks).

EDIT: I tried to find some screenshots of tracks I'd spectrally analysed to illustrate my point, but I can't find any, sorry, I guess I didn't save them.

 

[Mulder]

Yep, the bass in tracks is normally at a higher SPL level than the rest of the frequency range, which you can see if you spectrally analyse a few tracks. And you'll also have picks that are even higher, as when you spectrally analyse a track often the graphs are based on average trend (not peaks).

EDIT: I tried to find some screenshots of tracks I'd spectrally analysed to illustrate my point, but I can't find any, sorry, I guess I didn't save them.

Yes, but at the same time, tests have shown that human hearing is almost immune to distortion in the lower frequencies. It takes very high levels of distortion in the lower frequencies before it can be perceived.

 

[GM3]

But how audible would it be vs if it didn't have the distortion spike? It's not like from <200hz the entire bass distorted. At 94dB, the frequency which clips (1%) is something like 220-240Hz So thin frequency range. Then if you look at 0.5% THD, then you're around maybe 215 to 260? So about ~50Hz wide band. It's a bit wider in the frequency spectrum, but it's 0.5% distortion...

Again, if you compare to HD600 lets say, the entire spectrum below ~70Hz is MUCH WORSE...!
https://www.audiosciencereview.com/forum/index.php?threads/sennheiser-hd600-review-headphone.23233/

And yet, plenty of people have been listening to the HD600; considered a classic, great sounding, nobody has ever said that these are un-listenable garbage because the bass is above 1% at 94dB... So sure, latest comments above probably all true, but again, in the end; how audible is this distortion?

In this case, not everything under 200Hz, it's a very small frequency range in upper bass. It's not like a +20dB or -20dB frequency boost or cut, that would 100% jump at you if you listened to it, it's 'just' distortion; which at 94dB, is ~<1%. It shouldn't be hugely audible. Sure, at higher SPL, it becomes worse, and music is dynamic, so louder the worse it becomes... But how perceivable would it be on most music if you listen at normal listening volume, or slightly loud; not excessively loud?

Like what particular instrument or sound/note would make it audible? I'm pretty damn sure that if you took 100 random songs, you might be able to spot the distortion only on a few of them, and again, likely only if you were looking for it, especially if you do not listen very loud. Anyway, maybe I'm 100% wrong here, does anyone know of a song that would highlight this issue, given a set of vocals, instruments, sounds, etc.,?

Anyway, not purposely trying to fanboy or defend, (maybe subconsciously? lol), but I'm genuinely curious how audible it would be. As someone owning 400i and others, and being annoyed at flaws and all and hoping for 'best' budget sounds great, with no flaws, no distortion, neutral, etc., S5X seemed one of the better choices. Sure, looks 'bad' on graph, but like so many other headphones or speakers with measured flaws, I'm seriously doubting that this issue would be really audible; significant. Better if it wasn't there. But before measurements, nobody ever seemed to complain about it that I saw; so couldn't be too serious an issue...