[stellarelephant]

Nraymond says Penon Audio stocks them.

So I have some good news, Penon Audio is a source for a replacement battery! I wasn't entirely happy that the best I'd been able to find was that 1200mAh battery from Adafruit (which wasn't designed specifically for the XDuoo X3, but happened to physically fit and have some of the specs match, but the capacity was lower, the cable connector would have to be re-terminated, and it wasn't clear to me if there'd be a charging issue when supplying greater than 500mAh of charging current).

I had first sent an email to service@xduoo.com about a replacement battery but I didn't get a response. I had also emailed info@rtwhifihouse.com (the listed USA Sales Agent on the XDuoo website) but they said they didn't carry the battery. I had remembered Penon Audio (which is based in Hong Kong) as a reseller that had been mentioned here at Head-Fi before, so I contacted them through their website:

http://penonaudio.com/index.php?route=information/contact

They said they do stock the XDuoo X3 battery for $13, and shipping to where I am in the USA was $4.60. They created an invoice for the purchase via Paypal, and hopefully I'll have a battery soon! I wanted to mention it here for anyone else looking for a replacement.

 

[Slater]

Yet another reason why Penon is

 

[Bob A (SD)]

Nraymond says Penon Audio stocks them.

Has he reported on it after receiving it?

Appreciate the lead here to Penon!

 

[JayceOoi]

Great news, XDUOO X3 is selling at $75.99 with this code - RXDUOO
http://www.gearbest.com/mp3-mp4-players/pp_440370.html

 

[yangian]

Had an opportunity to A/B X3 with Fiio X5iii. To be honest, I can barely tell the difference. X5iii seems more neutral and bit more quiet. Tested with IE800.

 

[Slater]

In case anyone is interested, the XDUOO X10 on sale right now at Gearbest for $117.99 (code X10HDS).

http://www.gearbest.com/mp3-mp4-players/pp_609109.html

 

[Bob A (SD)]

Has he reported on it after receiving it?

Well over a week and no response to a PM to mraymond about this replacement battery

 

[artnoi]

well I think my unit is a bit strange.
First I got it for $88 on Aliexpress plus a 32GB mSD. Second it didnt come with warranty card. And third, with stated 250mW @32 Ohm shouldnt it be a hell more powerful than iPhone? But I find myself playing files at 60-70 when using earbuds, and around 50-60 when using IEMs, which is at the SAME LEVEL of my iPhone!! Is it POSSIBLE that my X3 is a fake one? Or is this device power output can just drive cans to the same level of loudness? (when at the same volume level)

 

[Slater]

well I think my unit is a bit strange.
First I got it for $88 on Aliexpress plus a 32GB mSD. Second it didnt come with warranty card. And third, with stated 250mW @32 Ohm shouldnt it be a hell more powerful than iPhone? But I find myself playing files at 60-70 when using earbuds, and around 50-60 when using IEMs, which is at the SAME LEVEL of my iPhone!! Is it POSSIBLE that my X3 is a fake one? Or is this device power output can just drive cans to the same level of loudness? (when at the same volume level)

Nah, there's been zero reports of any fake xduoo products.

It's 'power' is inversely proportional to the impedance of your headphones. Using 16ohm headphones, they should make your ears bleed. With 300ohm headphones, the X3 will choke.

Also, are you using the stock firmware or Rockbox?

What iPhone model?

 

[davedm]

Volume level is not indicative of power as different products might employ different volume curves. The ideal way to check power is at full volume. Therefore you could do one of the two things.

1. Find a pair of headphones from your collection that you can safely play at full volume on X3. Then with help of your ear or spl meter apps on your phone measure the spl. Then connection the same headphones to your iPhone at full volume and repeat the process and compare the results.
2. With help of a multimeter and a junk cable /jack, measure voltage at full volume for both devices and compare.

Needless to say, you need to use same track, ideally white noise to get better results. Do keep us posted.

 

[Igor Ruzaev]

Kinda sad to pay 17 bucks each time your battery is dead. That's nearly 1/4 of player cost. Moreover, it's hard to find the replacement. ahaha.

I realy love my X2 but will definitely stay away from xDuoo products in the future. No support from the manufacturer after release.

 

[artnoi]

I usually boot my X3 to stock fw though it also has Rockbox installed on it. I prefer the original fw because the lossless playback and the hiss with sensitive IEMs is much less audible than with Rockbox.
Today I tried the X3 with my most sensitive cans AK JH Michelle (for my listening volume) and my most tolerable and robust headphones Alessandro MS1i (for max volume test) against my iPhone 6S and 4, playing the exact same files (well, not quite exact since they were resampled to 48kHz on X3 to fix the pitch problem).
I set the volume on X3 to be 60 with +6dB gain. And to drive the IEMs to the same volume, my iPhone 4's volume was set to 60% max as well.
For your recommended method of applying max volume, I first try with iPhones to avoid damage to my cans' drivers if the assumption that its output power is lower than the X3. At full volume, iPhone 4 drives Alessandro MS1i quieter than X3 does at 90 level. And when the volume of X3 approaches 100, MS1i can get even louder, audibly noticeable without having to wear them.
So what are your thoughts?

 

[davedm]

Hi artnoi,

First of all, as @slaterlovesspam has already mentioned chances of your X3 being fake are almost nil as there are no reports to this effect till date. So rest assured that your X3 is original.

Secondly, Xduoo's claim of 250mW power is inflated as the max. actual power is on ~154mw as measures by two independent sources, Headphoniaks and Reference Audio Analyzer.
Still, This power is more than what your phone can provide especially iPhone 4. As reported by phonearena, iPhone 4s has maximum voltage of only 0.34V while iPhone 6s has 0.986V. X3 as reported by above two sources has maximum voltage of nearly 2.4-2.5V.

Xduoo X3 is therefore more capable to drive your headphones well. Now as to why it would sound equally loud at similar volume levels is because of different volume curve adopted by different manufactures. As you can see in the attached graph which indicate volume level on horizontal axis and voltage on vertical axis, to reach the same maximum volume you could take more aggressive route (red). In this case the sound will become loud pretty quick. Some manufacturers may adopt more conservative curve (blue) while ideal curve would be a linear one (green). Keep in mind that this only affects how quickly you achieve desired loudness/voltage, maximum voltage is same in all three cases.

So if your iPhones employ aggressive curves, they could match the loudness levels of a more powerful DAP which employs linear/ conservative curve. However the maximum volume will easily differentiate between the two as it is determined by higher voltage/power. This is why all measurements are done at a maximum volume level which will keep THD+N below a certain level (say <1%).

All said and done your alessandro ms1i at 32 ohms and 100 dB SPL/1mW are not that hard to drive, they probably need something like 0.1V to reach 90dB SPL which is pretty loud. Usually people listen well below that. So for this headphones either of your iPhones or X3 will drive them pretty loud but it is a different matter which you would like best with your headphones.

P.S. I also use stock firmware more than rockbox for simplicity and capability to decode higher res files.

 

[Slater]

Excellent explanation @davedm.

A similar idea is employed on drive-by-wire automobiles.

With cable-driven throttle bodies, the throttle opening had a linear relationship with the and pedal - you press the pedal all the way, the throttle opens all of the way. With the advent of drive-by-wire throttles (most cars nowadays), everything is controlled electronically. You could have the pedal mashed all the way to the floor, but depending on certain conditions (including how the manufacturer 'tuned' the throttle response) the actual throttle body may only be open a small amount.

But just like with volume curves, a linear throttle curve would be the best. Having everything electronically controlled isn't always the best. Anyone remember the runaway Toyota problem of a few years ago? That was an example of when a drive-by-wire system can go haywire (no foot on the pedal at all, yet throttle cranked wide open).

But I digress...

 

[artnoi]

and well to worsen the matter, I just noticed that my X3 has switched channels.. say, the right channel displays left signal.. Because the songs on my SD cards weren't the songs I daily listen to, but once I put my current songs into the mSD card and played them, all of them are played wrongly. Can it be that my unit is a defect one and therefore was sold cheap and the seller took out the warranty card?

EDITED: after I booted it to Rockbox fw it seems to work fine. So I booted to stock again and now the issue is gone. Maybe some bugs?