[Ynot1]

The package went to Cincinnati, Ohio. DHL hub I suspect, and skipped my state. I've avoided treble hot earphones mainly because I didn't think it was my style. I prefer bass to be plenty good. But then I read XE800 was treble hot, but it sounds balance and treble ok to me. We'll have to see when F9p arrives.
But is it me or this cold front making my earphones more refreshing? Physics wise cold makes things shrink and more dense, and it could be my ears sensing the improved efficiency of the diaphragm movements through the colder air. I guess it wouldn't matter if F9p got here already.

 

[FiiO USA]

Arrived yesterday evening late. With some other things going on for work I didn't unbox until today. First thoughts are they are very much an F9 in all details but the spike is not nearly as pronounced so they are indeed more listenable than the F9 for those of us that struggled with the treble. In putting them side by side with the Magaosi K5, the b400, the Lz a4, and the AKG N40, Initial impressions are N40 > F9P > b400/LZa4 > K5 which in the overall is not surprising except that I thought I would probably like the b400 better than the F9P based on my experience with the F9. This tells me that spike was probably making me miss other details about the F9 due to distraction. So far, I really like this one.

Can not wait to read your review of F9 pro and F9.

 

[Wiljen]

Really blown away with these. One of my all time heros is Van Morrison. I've seen him live any time he has come within 1000 miles of home. Moondance popped up on my N3 this morning with the F9Pro attached and it was the most realistic presentation of Van's voice I have ever heard from an in ear. I'm buying a pair of these if nothing else to listen to Van. just Wow! - Well done Fiio.

Oh, I should mention, I am using the balanced cable with a resistor modded Walnut F1 (Muses Opamp) tied to the Cayin N3 as source.

 

[Ynot1]

It appears F9p don't need burn in to sound good right out. A bonus for tour members.

Looks like no chance in 2017 for DHL delivery.

 

[Brooko]

No IEM will require burn-in.

 

[buonassi]

The supposedly 7k-ish peak is where no real instruments makes sounds. So it depends on the music if this is even detectable.

well, I politely disagree. Musical instruments make sounds up to 15k, after that, it's "air and space", which is good for those who can hear it, but not necessarily fundamental to the tonality/timbre of instruments and vocals. there's a lot happening between 5 and 10k for instrument and vocals. 7K is right in line with the "s" and "t" consonant sounds that come through on poorly mastered tracks. This is also an area where a lot of cymbal action is taking place. Furthermore, it's where ear canals can resonate, increasing the perceived loudness around 7k region (depends on anatomy and insertion depth). So, IMO any spike in this area is detrimental to the timbre and leads to metallic sounding cymbals, "digititus", and fatigue. Of course, the music genre (and quality) you listen to may not present as harshly with a 7k peak as rock or metal where the treble is hot to begin with.

My theory on response graph not showing benefits of balance is ground channel separation happens to improve isolation for all frequency all the time, while the technique to measure response looks at only one point in the spectrum at a time.

Bingo - very well put! There are benefits to balanced that will absolutely not show on a traditional FR graph.

Anyway, a side note: By the time I get these for review, I should have my new amp and DAC in, which will act as another point of reference for these IEMs. new amp is an Arcam rHead, with very low output impedance and near reference quality. My new DAC on the way is iFi iDAC2 with the iFi nano iUSB 3.0 power supply/reclocker in line with it. Along with my x5iii, Shiit Asgard2/Modi Multibit, I should have plenty of sources with which to evaluate the F9Pro. Oh, and I have an army of tips to try on them including the (in)famous spinfits and spiral dots, as well as foams from comply.

 

[Wiljen]

the F9pro comes with an impressive tip selection already - you may not need your army.

 

[Brooko]

Bingo - very well put! There are benefits to balanced that will absolutely not show on a traditional FR graph

What audible benefits are those? The only one I know of which has an audible effect is power, or impedance (if the balanced out has a different impedance).

Impedance doesn’t seem to affect F9 or F9 Pro (I have measured), and neither require or benefit from extra power. So what other audible benefit is there? If you’re thinking crosstalk - then you might want to consider this .....

The FCC minimum channel separation/crosstalk spec for FM Stereo used to be 29.7dB...yes, that's right, 29.7. It had to do with how the signal was generated and handled, but 30 - 40dB wasn't hard to achieve, and 50dB wasn't uncommon.

The bulk of what is perceived as stereo separation happens above 20dB with decreasing detectable improvements above 30dB or so. It's almost impossible to detect separation improvements above 40dB. Localization of a phantom image depends less on channel separation and much more on relative intensity and inter-aural time delay of the sound, and human hearing response at different angles.
So....long answer...separation above 40dB doesn't improve sound quality, below 40dB it slowly degrades, the final separation is equal to the device with the least separation in the system. Once degraded by a device, no device following it can restore separation.

Short answer - unless the SE output is faulty by design, balanced has no audible benefit.

So why do people think it has these magical benefits?

1. Good marketing
2. People not understanding what the numbers mean
3. Most people don't volume match, and we are terrible at volume matching by ear (which is what a lot of people do). Most balanced circuits output a lot more power by design - therefore they are louder. People saying they hear a difference are often simply listening to one louder than the other. And we know louder is perceived as sounding better.

So please - explain (along with example of appropriate source - so I can quote actual specs) where a balanced output would benefit the F9 Pro. Thanks

 

[Wiljen]

I wasn't attempting to suggest that balanced was better for the F9Pro. In fact, my choice of using the balanced cable was based on my personal dislike for microphone/remotes on my cables. The 3.5 SE cable that shipped with the F9Pro has the microphone so while I will use it enough to be sure the controls and microphone work satisfactorily, I much prefer a cable without the mic which led to the choice to go balanced. As far as dumping more power to the F9pro via balanced cable, my op amp on the Walnut has 18K ohm resistors in parallel to reduce the output substantially. The stock F1 would have been way too much to pair with the F9pro or most other in ears. Unmodified the Walnut F1 is best suited for full-size cans or very power hungry cans. Maybe the Havi or other notoriously power hungry in ears would work but with most fairly sensitive in-ears (read F9pro) you would only have 5-10% of the available volume range usable without doing hearing damage. Even with the resistors in parallel, only roughly 35% of the total output power is needed to listen as loud as I can stand without it really getting bothersome. I would suspect 100% would still be damaging to your hearing and the distortion would likely be pretty horrific too.

 

[buonassi]

What audible benefits are those? The only one I know of which has an audible effect is power, or impedance (if the balanced out has a different impedance).

So please - explain (along with example of appropriate source - so I can quote actual specs) where a balanced output would benefit the F9 Pro. Thanks

I tend to agree with you that there aren't audible differences in my chain when I compare balanced to single ended. However, I also don't want to be diminutive to those who do hear audible differences in their fully balanced chains. Much like I wouldn't tell someone there is no audible difference between a minimum phase vs linear phase filter on their DAC - or that their silver plated copper USB cable doesn't help audibly - or that upsampling done in software vs oversampling done in their DAC isn't sonically better. The takeaway from my reply was that any benefits wont show on a FR graph. But there are also objective/measurable benefits to using balanced. And knowing what little I do know about the science behind electrical currents, they seem to make sense:

"Balanced-drive delivers a noted increase in audio performance due to the doubling of the amp's voltage slew rate and voltage swing range, a reduction of THD (Total Harmonic Distortion) components and the avoidance of crosstalk due to the elimination of the common ground plane."
https://www.headphone.com/pages/balanced-headphones-guide

My theory is, and it's just my belief, not proven: If you're better isolating what gets fed to each channel, then each driver has to work slightly less (reproducing less of the information in the original source file's opposite channel). Then again, we're talking about a 15-20db attenuation (vs single ended typically) of the opposing channel's information, so it's not a huge amount. Still, in theory should make for a cleaner signal right? Less distortion perhaps?

What's not my theory and can be shown scientifically to be true, voltage swing and slew rate are directly related to controlling transients. Volts drive the transducers. The amount of voltage that can be ramped up or down is voltage swing, while the rate at which that ramping happens is the slew rate. If you've listened to a very good amp like the violetrics or lakepeople with a Senn HD600 or better, I think you'd be able to agree on the superiority of those amps. So the fact that you are able to send those volts independently to each channel at double the swing and slew will make for a tighter performance generally speaking. But will that have a benefit to the F9 as much as it would a headphone that requires much more voltage? Probably not.

In summary, you can't show the benefits of balanced on a simple FR line graph, but there are objectively proven benefits to this topography. The realized benefits of balanced drive even to the most discerning of enthusiasts, however, is a pretty small increase in SQ that requires a fully balanced chain, very discerning ears, and highly resolving headphones. The benefits of the F9 going balanced probably wont add anything very apparent.

 

[Brooko]

Like I said - power is a given. If your headphone is being underpowered, then the additional voltage may help. However if the amp has the output in single-ended to fully drive the headphone, more power will do nothing. And if the headphone is audibly underpowered - the difference actually should show in frequency response. As to other measurements (eg crosstalk, SNR, and even distortion) I am yet to see any decently designed amp where the difference between single-ended and balanced is audible when the headphone is being powered properly, impedance is virtually the same, and the comparison is properly volume matched.

So again - if the benefits can be shown using other measurements, please provide examples (both the amp and the headphones + measurements) and also how they are audible.

The reason I comment and ask for examples is simple - many people make statements regarding balanced audio output, and for power, or long runs of cables where crosstalk could be an audible issue (eg recording studios) I have zero issues with what you said. For normal playback ....... I’m yet to hear an advantage. When others have made the statement, and have agreed to a proper volume matched blind test, those differences seem to disappear.

If the difference is not audible - how can it be called a benefit?

Sorry - hobby horse of mine. There are enough urban myths in personal audio. I simply like to bring the debate to the fore - so that others won’t be unduly influenced. Expectation bias is very powerful. I’d rather have people note perceived changes as what they actually are most of the time (poor volume matched comparisons).

 

[Brooko]

The benefits of the F9 going balanced probably wont add anything very apparent.

I’d adjust this to:
The benefits of the F9 going balanced wont add anything audibly apparent - once volume matched.

 

[buonassi]

I get it... And appreciate your skepticism of these things. I know that expectation bias is a real thing. I haven't been able to pin down any audible difference myself.

Also to your point , seems all the development effort goes into the ballanced out on most multi out headamps. This could be another reason why the experiences of folks tend to come out positive for balance.

All good points. I'll have to do some extensive a/b/x before I'm convinced it's worth all the money. Rather sink that cost into a new dac, amp, or cans.

 

[buonassi]

Also, I'm a fan of crossfeed so what the heck do I really care anyway! Good dialogue though.

 

[Ynot1]

Happy New Year! And still no DHL.