[x RELIC x]

Allow me to quote myself to ask a point-blank question: which has more power, the X5ii or my JDS C5 portable?

Here are their published specs:
(they are not the same units as so I don't know how to compare)

C5
Max Output at 600 ohm: 4.146 VRMS
Max Output at 150 ohm: 3.580 VRMS
Max Output at 32 ohm: 1.182 VRMS
Power Supply: 14.0 Vpp
Output Impedance: 0.62 ohm

X5ii
Output Power 3: >27 mW at 300 ohm
Output Power 1: >245 mW at 32 ohm
Output Power 2: >436 mW at 16 ohm
Max Output Voltage: 8.2 Vpp
Max Output Current: 250 mA
Output Impedance: 0.2 ohm (32 ohm)

I'm pretty sure the C5 strictly has more power. But in the big picture, is this a meaningful difference compared to, say, my JDS Atom or any other desktop amp? And what does this mean for my three sets of headphones?

Power = Voltage*Current so you aren't really looking at comparable specs. All the C5 spec is showing with the different VRMS specs is that as the impedance drops so does the Voltage requirement, but the Current requirement will increase. This is the biggest thing that 99% of people on Head Fi miss... The impedance is more an indicator of the ratio between Current and Voltage used, not a full indicator of drive ability.

Look for the sensitivity spec on the headphones you own. This will be MUCH more meaningful regarding how much power they need. The only caution is that some amps are Current limited below a certain load (resistance) so the ability to drive very low impedance transducers will dramatically fall off if the amp is Current limited (some tube amps for example).

Use this link to give you an idea of how much power your headphones need, you will be surprised at how low the number is because, unlike speakers, the distance calculation is not needed and the mass for the transducer is much lower than speakers. Just plug in the sensitivity and the impedance and then click the calculate button:

http://www.digizoid.com/headphones-power.html

Vmode XS

For the Vmoda XS this is what you need for power, broken down by Voltage and Current as well (you can see it's very little to blow your ears out):



Sennheiser Amperion

The Sennheiser Amperion specifies 120dB sensivity but I can't find if it's per dB SPL/V or per dB SPL/mW (there's a difference) so I didn't calculate it for you. However, either way they are extremely sensitive and can be driven from pretty much anything.


Sennheiser HD600

Here is the Senn HD600. You can see that at 300 Ohms you need more power than the X5ii can output for 115dB peaks, but... 110dB is still LOUD. Personally I don't like wincing when I hear peaks that loud in my music.



The relationship between power output and the transducer (headphone) is such that as more power is applied then more volume is produced. Extra power 'available' isn't being used unless the volume is increased. Simple as that. You'll read all over Head Fi the many debates that a user has enough volume but not enough power. This is a complete misunderstanding of how transducers work. The design, implementation, tuning, synergy with amps is more important than just power amount. Also, when comparing gear make sure you volume match devices as accurately as possible. As little as 1dB difference can lead one to think that the louder source is more spacious, better separated, more impact, etc., it's just the way the human brain/hearing is wired to prefer a relatively louder sound.

The whole point is that for the MAJORITY of headphones either device will serve you well. Use the calculator I linked as a ballpark but also realize that the overall design and implementation of the device is arguably more important that just the power spec. ONCE THERE IS ENOUGH power, and add a little headroom for different mastering levels, etc.. Look for synergy with your headphones as well. The more neutral and lower distortion from the headphone then the better you can discern the differences from the source gear if that's what floats your boat, vs enjoying the tuning of the headphone which can mask the potential qualities of the source gear (like the Vmoda). Either way, hopefully this will send you on the right path instead of just looking at the power spec.

 

[bzippy]

Thanks for that very generous post. That is very helpful.

There is one thing I still don't understand though. I take you at your word re this statement: "You'll read all over Head Fi the many debates that a user has enough volume but not enough power. This is a complete misunderstanding of how transducers work". But we've all experienced the effect of more demanding HP's getting plenty loud yet still seeming thin & unsatisfying (HD 600's driven by a phone's headphone jack for example). So what is that about? I know you said "synergy" between drivers and amp is important, but what factors are behind that synergy?

I ask this question because for years I happily drove my 600's with the C5 amp and almost always used it's Bass Boost feature after concluding that the 600's were just too rolled off at the bottom. I was happy to conclude that this was as good as they could sound and rejected/ignored all the stuff I read about them needing more power to perform their best (people just love to spend more & more, convince themselves that they hear a night & day difference, then try to convince the rest of us too). But my curiosity eventually got the best of me and I decided to try an entry level desktop amp: the JDS Atom, even though I did not expect much noticeable difference. But I was simply shocked at the improvements I heard, especially: (1) fuller low end, such that I found much less need for EQing on the bottom, and (2) greater space & instrument/voice separation. I thought both the C5 and the Atom have been found to have dead flat response and sub-audible distortion levels, so then to what do we attribute such significant differences in performance? Or are you saying that it is just so complex a system of factors that we can't simply point to any one thing to explain (or predict) the result?



I'm sorry I think I've pulled us significantly off thread topic here (perhaps this should be continued in the Amp or Science forum). Bottom line: I'm expecting to leave my portable amp home once I get up & running with the X5ii, even when I travel with my 600's. Reasonable?

 

[x RELIC x]

This thread has been asleep for a long period of time so hopefully others won’t mind yet another long post.

I haven’t heard the HD600 with the X5ii and I don’t know your exact preferences so I can’t say if it’s reasonable to expect the pairing to be ‘good’. Looking at your other headphones though I suspect the HD600 might sound a little bit ‘thin’ to you paired with the X5ii. Thankfully there’s an EQ on the X5ii. Hopefully this won’t be the case though and I would encourage you to report what you hear when the X5ii arrives. I know there are others that really like the pairing so take what I just said with a giant bucket of salt.

Regarding your portable phone question, remember that power is Current and Voltage together and most phones likely won’t be designed to deliver a wide range of delivery for various loads at various frequencies. Implementation. Here’s yet another car analogy on Head Fi. Both a compact hatchback and a sports car use gas to accelerate and both can get to 100mph, but the sports car will do it better and more enjoyably. That’s similar to implementation and tuning in audio gear. A smartphone isn’t a dedicated audio device so the overall implementation won’t hold a candle to a dedicated audio device (typically) as far as being designed to reliably deliver quality sound with a variety of transducer designs. There’s output impedance, slew rate, cross talk, SNR, distortion, power rails, and much more to consider. Yes, it’s a complex system of design and we really can’t say that just power output is the determining factor for quality. That’s simply the point I was making.

Regarding the difference from one amp to another. Does the Atom sound relatively warmer with every headphone/IEM you use it with compared to other sources? That’s tuning. It may be difficult to determine with the Vmoda and Amperion given their bass emphasis. The HD600 may sound better from the Atom compared to the C5 without bass boost simply because the Atom has a warm tilt (I haven’t heard it so I can’t make any conclusions here, just spit-balling). The HD600 is not really a headphone for me given what I'd consider flaws in the bass region, in today’s market, yet it has a strong following. To quote Tyll from Innerfidelity:

"In the compensated frequency response, you'll notice bass response falling off below 100Hz on all three cans. Additionally, the 30Hz square waves have a clear downward bend and the THD+noise plot shows rising THD below 100Hz. All three indicate a diaphragm that just doesn't have enough poop to continue to pressurize the ear chamber at the lowest frequencies, and yielding bass response that isn't well extended and lacks tightness."
Read more at https://www.innerfidelity.com/conte...0-and-hd-650-measurements#aU83IoVRbziJ1pGp.99

Too many times I read that people are compensating for shortcomings in the headphone (for their tastes) when they really should be considering different headphones IMO. I can’t tell you how many posts I’ve read that blame power for everything when the real issue is the headphone, or synergy. Example, I would never pair an HD800 with the bright Schiit Jotunheim amp despite the amp’s excessive power output, unless one really loves treble emphasis. One persons preference often does not equal another’s.

To speak to the opposite, when the ALO CDM was released it was applauded for being a very powerful portable tube amp that could drive full sized headphones with ease including the HD800. It only delivers max 145mW@50 Ohms with the balanced output, which is less than the X5ii. However, Ken Ball designs fantastic gear and knows how to implement a very rich and dynamic sound in his amps. Yet another assumption that it was a powerful source but it’s really based on its tuning and implementation. Perpetuated myths and ill informed conclusions at play. Second order harmonic distortion may not show up on a frequency response plot for an amp but it can easily warm up the sound, which is often the case with tube amps.

Also consider output impedance from the amp. For many dynamic driver headphones a high output impedance will alter the headphone’s frequency response and therefor alter the sound, even though on test equipment the amp measures flat. For example, Sennheiser’s HDV820 amp has a very high output impedance and is tuned warm specifically for the HD800 series headphones to compensate for their bright tuning. FYI, the theoretical ideal output impedance for an amp is zero, but that’s impossible.

Lastly, I would encourage others not to fall in to the trap of dismissing things as ‘not audible’ but also not to obsess over the idea. Of course there’s a threshold where audibility will come in to play but we really don’t know exactly where that is currently. The ear itself is actually a poor mechanical sound capturing device and the brain compensates extensively but we don’t yet know the exact mechanism for this. There are many studies ongoing with the ear/brain hearing system that indicate we do indeed perceive more than what was presumed in the past, especially regarding distortions (not heard as blatant distortion). Trust your ears when demoing gear and if you hear a difference then you hear a difference (after volume matching of course). If you don’t then you don’t, lucky you.

Sure, Sound Science forums will easily be able to ‘prove’ in abx testing that differences can’t be heard between gear, but abx tests often use too short of samples to be meaningful and our brains are simply terrible at quick comparisons, especially in a stress induced abx test. I wouldn’t dismiss abx testing entirely but it isn’t cut and dry regarding human perception. I find for perceiving subtle differences that a long demo of gear before switching for comparisons (around 1 week) is best to adjust to various nuances with a wide range of music that we need to acclimate to. Frankly, I stopped reading the Sound Science forums due to their dogma. From my perspective we listen to music for the experience and not to prove anything to anyone.

 

[Brooko]

If I may - I'll come at it from the opposite end (the sciency stuff), which can often tell us more about what is required. I respectfully disagree with Relic's comment :

Sure, Sound Science forums will easily be able to ‘prove’ in abx testing that differences can’t be heard between gear, but abx tests often use too short of samples to be meaningful and our brains are simply terrible at quick comparisons, especially in a stress induced abx test. I wouldn’t dismiss abx testing entirely but it isn’t cut and dry regarding human perception. I find for perceiving subtle differences that a long demo of gear before switching for comparisons (around 1 week) is best to adjust to various nuances with a wide range of music that we need to acclimate to. Frankly, I stopped reading the Sound Science forums due to their dogma. From my perspective we listen to music for the experience and not to prove anything to anyone.

The idea of an abx test is to use only our hearing to decide whether there is a difference. Not our sight. Not any other factors. Only our hearing. We do this by isolating all other factors. You can perform an abx test over hours, days, weeks - as long as you want. Its up to you. The importance is for it not to be sighted. Then only what you hear matters. Our ears are pretty good instruments - its our brains which are the culprit when it comes to interpretation on what we are hearing. The reason most people rely on short abx tests is because our aural memory is typically very short (in terms of accuracy). Past about 30 seconds, you can't do an accurate assessment of two sounds anyway. Its how our brains are wired.

I do agree somewhat on the comment on dogma - but if you spend some time on SS, you get to know who is worth taking notice of, and we do have some very knowledgeable people indeed. At least two I know of are both engineers and producers - so that creates an interesting paradox with the whole trust your ears, and not the measurements thing. These guys do both - but also acknowledge the issues with psycho-acoustic bias - which we can't avoid in sighted tests. This is a brilliant video to be aware of issues when we don't use abx.



The people in the video are experts in their fields. Poppy Crum for instance is the chief scientist at Dolby.

 

[Brooko]

Thanks for that very generous post. That is very helpful.

There is one thing I still don't understand though. I take you at your word re this statement: "You'll read all over Head Fi the many debates that a user has enough volume but not enough power. This is a complete misunderstanding of how transducers work". But we've all experienced the effect of more demanding HP's getting plenty loud yet still seeming thin & unsatisfying (HD 600's driven by a phone's headphone jack for example). So what is that about? I know you said "synergy" between drivers and amp is important, but what factors are behind that synergy?

I ask this question because for years I happily drove my 600's with the C5 amp and almost always used it's Bass Boost feature after concluding that the 600's were just too rolled off at the bottom. I was happy to conclude that this was as good as they could sound and rejected/ignored all the stuff I read about them needing more power to perform their best (people just love to spend more & more, convince themselves that they hear a night & day difference, then try to convince the rest of us too). But my curiosity eventually got the best of me and I decided to try an entry level desktop amp: the JDS Atom, even though I did not expect much noticeable difference. But I was simply shocked at the improvements I heard, especially: (1) fuller low end, such that I found much less need for EQing on the bottom, and (2) greater space & instrument/voice separation. I thought both the C5 and the Atom have been found to have dead flat response and sub-audible distortion levels, so then to what do we attribute such significant differences in performance? Or are you saying that it is just so complex a system of factors that we can't simply point to any one thing to explain (or predict) the result?



I'm sorry I think I've pulled us significantly off thread topic here (perhaps this should be continued in the Amp or Science forum). Bottom line: I'm expecting to leave my portable amp home once I get up & running with the X5ii, even when I travel with my 600's. Reasonable?

Bzippy - you've posed some good questions. I understand some of it but not all. Suggest first reading this article:
https://www.innerfidelity.com/conte...ents-explained-electrical-impedance-and-phase

The HD600 has extremely similar measurements to HD580 - in frequency response, phase and impedance.

While the HD600 has a 300ohm nominal impedance, this actually rises to over 500 ohms at the drivers natural resonant frequency (which exists at approx 90-110Hz). My understanding is that despite the higher impedance at this point, its actually the easiest frequency to drive. But because of the relative height of this spike, as you move away from the resonant frequency it starts taking more voltage to drive current to the drivers. Most high impedance dynamic drivers are like this. They don't require gobs of current (unless they have low sensitivity), but do require higher than normal voltage.

It's difficult to ascertain the output on the C5 because they give very few specs they give. Looking up the chipsets and comparing to the very similar FiiO A5 (power output almost identical), we can make a reasonable assumption that the max voltage output should be around 15Vp-p. Comparatively the X5ii's max voltage output is ~ 8.2Vp-p. The C5 is capable of putting close to double the voltage into a higher impedance load.

With the HD600 requiring higher voltage to drive current, we can expect that there may be issues with sub-bass from a source which does not have sufficient voltage output - even though the current output (overall volume) is high enough.

Don't get me wrong, the HD600 actually sounds pretty decent on the X5ii (I have both), and it gets to a good overall volume. But you may find it sounds subjectively better on the C5 plus you also have the bass boost if you need it. Typically with the HD600 (or HD800S), I always use a dedicated amp, or higher output amp module (X7ii/Q5) if going portable.

 

[x RELIC x]

I thought you’d chime in Paul, and I appreciate your insights. We may disagree with certain aspects of what we perceive and the root of such, but that’s not to say we are mutually ‘wrong’. You speak of our brains being influenced subjectively rather than objectively, and I agree with this. However that’s not what I was referring to. For example, our ears are poor at capturing bass with bass roll off and distortion and it’s our brains that use transient information to help define bass pitch and timbre better. Experiments have been done where leading edge transients have been removed from piano and trumpet recordings and the test subjects had a very difficult time telling the instruments apart. There’s more than just our mechanical ear system that interprets what we hear. Not all engineers / scientists look in the same places or come to the same conclusions.

Yes, eliminating sighted comparisons are helpful to eliminate expectation bias. No argument from me there and it can be a very useful tool. However there is a conundrum in that our aural memory is poor and yet quick comparisons don’t usually have enough variation to pick up every difference that may be heard. Abx may be good to eliminate expectation bias but doesn’t prove what may or may not be audible in every situation.

Anyway, my Sound Science paragraph wasn’t the main point of my post and I’d hate to go down that rabbit hole here so please don’t cherry pick the point for debate (I know you are just clarifying points though). I was basically trying to express (likely poorly expressed) that IMO personal enjoyment is the most important factor rather than listening to others dictate what one enjoys or not.

 

[Brooko]

Oh I agree that the one measure should always be the pleasure the machine gives you.

For instance, I use the upscaling tool in Media Center to always send the digital file to my iDSD dac in DSD format. It lights a pretty teal light on the iDSD, and it somehow makes it sound better. Now I’ve already abx’d the difference and it’s inaudible to me - so the pleasure I’m getting (sounding better/different) is actually imaginary. I know this - but it makes no difference to the experience.

The difference is that you won’t ever hear me claiming the DSD output is better. I know it’s psycho-acoustic. I know it’s brain taking other factors into account. But I’ll keep doing it - because it gives me pleasure

 

[bzippy]

I'm just jumping in to quickly to ask if anyone has any X5ii cases that they don't need or wouldn't mind getting rid of. I got mine yesterday and it came with the Tuff-Luv leather case. It's really nice but it's just too bulky for my needs. The Dignis one or the FiiO leatherette one look much better. I'd even be interested in FiiO's silicone one. (there's literally nothing left online, not even ebay)


AND Holy Effing OMG -- look at all this great stuff to read and watch! I don't have time right now, but tonight I hope. Thanks so much you guys.

 

[trivium911]

For those of you thinking about buying an X5ii, I wouldn't bother. I really get the impression they don't stand by behind their products and I will never buy one of their DAPs again. My X1 charge port melted after 2 years of ownership almost causing a fire, my X3ii still works but is in need of a battery and the sleep mode works only half the time leaving my battery dead the next day. First off you can't get replacement batteries, apparently they don't ship to Canada which is not true...I buy batteries all the time for devices from china. I've emailed them a dozen times but they never respond about the battery. Furthermore, on my X5ii there is an inherent issue with the firmware which was never fixed, I researched and I'm not the only one. When you long press to skip through the track... the sleep mode will not work in the now playing screen. You have to either restart the device or hit the back button to go back to the menu to get the standby mode. Furthermore an issue just popped up where it keeps entering dock mode and stops the music, basically rendering the device useless. It happens at random...either way you might spend a bit more up from with an ibasso or cayin, however they make up for it by having a complete product and the unit lasting longer. Besides the battery, is anyone else having these issues? I mean I've had cell phones last long than this has...and I have always been able to get replacement batteries from China. So at this point I'm done with their Dap's

 

[Pewterlocks]

For those of you thinking about buying an X5ii, I wouldn't bother. I really get the impression they don't stand by behind their products and I will never buy one of their DAPs again. My X1 charge port melted after 2 years of ownership almost causing a fire, my X3ii still works but is in need of a battery and the sleep mode works only half the time leaving my battery dead the next day. First off you can't get replacement batteries, apparently they don't ship to Canada which is not true...I buy batteries all the time for devices from china. I've emailed them a dozen times but they never respond about the battery. Furthermore, on my X5ii there is an inherent issue with the firmware which was never fixed, I researched and I'm not the only one. When you long press to skip through the track... the sleep mode will not work in the now playing screen. You have to either restart the device or hit the back button to go back to the menu to get the standby mode. Furthermore an issue just popped up where it keeps entering dock mode and stops the music, basically rendering the device useless. It happens at random...either way you might spend a bit more up from with an ibasso or cayin, however they make up for it by having a complete product and the unit lasting longer. Besides the battery, is anyone else having these issues? I mean I've had cell phones last long than this has...and I have always been able to get replacement batteries from China. So at this point I'm done with their Dap's

The thing with Fiio and others, is that once a X??? Is out, it starts to be redundant as the " next one" is coming down the pipeline. You may get a FW upgrade or two if you are lucky. More often then not you WILL get a incomplete FW as resources are not readily available. Fiio which in terms of sales and marketing's seems to be the larger of the companies not names Sony so maybe a little less slack when it comes to them. Here in Canada it is pretty easy to get Fiio products, whereas others such as Shanling, Cayin, Ibasso are limited. I have owned my X5 2 from the beginning and it still works like new. I still love the sound and have had only minor issues with it that weren't user error.

Just my 2 cents

With all this been said, I really do have issues with putting out my cash at any price for an incomplete item and then being a product tester as most companies all do it to some degree, but it seems everything now is a buggy product ( software, games). We are all testers now for everything, damn this is getting scary. Lol

 

[trivium911]

The thing with Fiio and others, is that once a X??? Is out, it starts to be redundant as the " next one" is coming down the pipeline. You may get a FW upgrade or two if you are lucky. More often then not you WILL get a incomplete FW as resources are not readily available. Fiio which in terms of sales and marketing's seems to be the larger of the companies not names Sony so maybe a little less slack when it comes to them. Here in Canada it is pretty easy to get Fiio products, whereas others such as Shanling, Cayin, Ibasso are limited. I have owned my X5 2 from the beginning and it still works like new. I still love the sound and have had only minor issues with it that weren't user error.

Just my 2 cents

With all this been said, I really do have issues with putting out my cash at any price for an incomplete item and then being a product tester as most companies all do it to some degree, but it seems everything now is a buggy product ( software, games). We are all testers now for everything, damn this is getting scary. Lol

When the X5ii works it sounds decent no doubt, it's true that other products are hard to come by but no impossible in Canada. It's likely easier for you in fact in Ontario as there are a few suppliers. At any rate I'll likely be looking at a Cayin N5ii in the future...apparently it's it's got the n3 sound quality but with more features... Its hard to go back to a single SD card slot after having two.

 

[Tuneslover]

I used to use my X5ii as a portable device as well as my source device for my home headphone setups. The travel stopped 3 years ago so it is exclusively being used as my source music storage and digital transport into my standalone DACs. It has been used to great extent with some glitchy performance but for the most part it has been reliable. The thing that annoyed me though is that even in firmware updates there were issues and users complained about "premature" updates without sufficient testing. Then once a new player is released FiiO all but abandons existing older models that haven't even had well known glitches resolved leaving their customers in the lurch. That has me re-thinking about my eventual next DAP (because at some point in time my X5ii will give up the ghost). I also love the 2 microSD slots giving me the capability to have my entire music library within a single compact device. I haven't looked too seriously into any other DACs as a potential replacement but at some time it will have to happen. Although I do like the FiiO devices I'm uncertain that I will buy another one (I also owned the X3 briefly and then upgraded to the X5II when it was released) due to the lack of future support.

 

[Pewterlocks]

When the X5ii works it sounds decent no doubt, it's true that other products are hard to come by but no impossible in Canada. It's likely easier for you in fact in Ontario as there are a few suppliers. At any rate I'll likely be looking at a Cayin N5ii in the future...apparently it's it's got the n3 sound quality but with more features... Its hard to go back to a single SD card slot after having two.

Yes you can find other than Fiio, that being said the cost is screw*n stroke inducing crazy. I look quite longingly at yes you Cayin, Shanling and of course Ibasso and I just can not justify the cost ( wife) .
Often when I am weak,which is at a crackhead kind of weak, I check out musictek as when they are on sale, the cost even after the exchange rate is still better then a Canadian price. Lol
I too want dual card slots as I want all my music with me when I am out as I never know what I am in the mood for. If you know any good Canadian places, please share

 

[trivium911]

Yes you can find other than Fiio, that being said the cost is screw*n stroke inducing crazy. I look quite longingly at yes you Cayin, Shanling and of course Ibasso and I just can not justify the cost ( wife) .
Often when I am weak,which is at a crackhead kind of weak, I check out musictek as when they are on sale, the cost even after the exchange rate is still better then a Canadian price. Lol
I too want dual card slots as I want all my music with me when I am out as I never know what I am in the mood for. If you know any good Canadian places, please share

There is an ibasso dx120 going on eBay shipped for just under $500. I'm not looking to spend the money right now but perhaps in the future...headphonebar in Vancouver is usually ok but the prices are not great (shanling m5s is $600 Cad)... Their options are limited aswell. Justifying the cost to the wife is pretty difficult so you're not alone, as its far from my only hobby. Making wine on the side and oak barrels are also expensive

On a side note I also have the new X1ii for the wife and the UI is useless (laggy and slow), a step back in my opinion.

 

[trivium911]

For those that are interested it looks like the battery can be purchased here:

https://www.aliexpress.com/item/Bat...700.html?spm=a2g0s.9042311.0.0.50fc4c4dBw2Yiu

I just bought one to replace my crappy ebay generic one that was likely sitting on the shelf for a year before i installed it which is likely why is has a terrible run time. You need the iphone mini torx removal tool to remove the two screws at the bottom.

https://www.ebay.ca/itm/8-in-1-Repa...s-6-5-5S-SE-/283463549466?hash=item41ffbe821a