iBasso AMP14 Review
iBasso AMP14 Review
The review sample was kindly provided free of charge in exchange for an honest review.
I didn’t receive monetary or any other kind of compensation and I don’t use affiliate links.
The price of the AMP14 is $279 and you can order it from iBasso shop.
The iBasso AMP card system
If you are new to the iBasso ecosystem then you are probably not familiar with the replaceable amplifier module system of their DAPs, the DX240, the DX300 and DX320
All these DAPs feature a replaceable AMP card design where the user can easily install one of the available amplifier modules to slightly modify the sound signature of the player with each card.
Their flagship player, the DX320 comes with the AMP11 MK2s installed as a standard and there are three other modules available.
The class A discrete balanced AMP12, the Nutube single ended AMP13 and the brand new iBasso AMP14.
All these amp cards are also backwards compatible with their previous flagship player the DX300.
The iBasso AMP14 uses one 6th generation triode Nutube 6P1, also found in the AMP13, as a voltage amplifier but now is followed by a JFET differential converter to realize a differential output.
iBasso AMP14 adopts two JRC volume control chips which form a total of 4 channel true balanced volume control.
The signal then passes through the 4 channel balanced output buffer stage to give 5.2V RMS from the 4.4mm headphone socket while there is also a dedicated balanced line output with 1.8V RMS, which is much lower than the 4V industry standard.
In case that you need a full scale 4V balanced line output then you should consider AMP12.
Additionally, the iBasso AMP14 adopts a cathode input with an impedance lower than the grid, resulting in reduced signal interference from external sources.
iBasso AMP14 is designed to have excellent noise floor control and low WiFi interference, which brings a better online streaming experience.
The tube microphonic effect is also well controlled.
The AMP section of the DX320/DX300 has its own battery power, which is perfect for the iBasso AMP14, as it is an AMP card with strict power supply requirements.
The iBasso AMP14 utilizes two pieces of high performance DC-DC chips from Linear Technology, with a total of 4 DC-DC power supplies.
One DC-DC is 3.6V for the cathode through a low-noise LDO, and one is 14V for the anode of Nutube, one is +8V and one is -8V, which constitutes the 16V voltage swing that feeds the op-amps.
You can read more here
The iBasso AMP14 comes well packed in an ESD protection bag and you must be careful not to touch the internal components during the installation.
Together with the AMP14 you will find a hard carrying case for storing the card that is not used, a hex screwdriver, an extra set of screws, adhesive foam tape and a clear TPU case for your DAP.
The DX320 comes with a leather protective case as a standard but with AMP14 and AMP13 you can use the transparent so you can enjoy the glowing effect at the back side of the player.
Noise floor and associated equipment
The iBasso AMP14 was burned for more than 100 hours as suggested by the manufacturer and the evaluation was done with the DX320.
During the evaluation period I used various headphones, ranging from the Meze Elite to the Focal Clear Mg and more sensitive earphones like the FiiO FH9 and FDX or the Unique Melody MEXT.
One notable difference between the AMP13 and the AMP14 is that the latter is considerably more noise free, almost dead silent, it doesn’t get affected by WiFi interference and it has extremely low microphonic noise.
You have to tap the chassis with force in order to hear microphonic noise while I didn’t experience any wireless interference whatsoever although I did all the evaluation listening exclusively to streaming services.
Power output is definitely sufficient for all the regular sensitivity headphones but while 5.2V is definitely more than the 4.1V of the AMP13, it can’t reach the whopping 8.3V (2000mA) of the AMP12 or the 7.1V of the stock AMP11 MK2s.
Exactly like the AMP13, the iBasso AMP14 benefits from some warming time and sounds at its best after about half an hour of music playing.
The following section includes comparison references to all the other three AMP cards that are available for the DX320.
Coming from the AMP13 I was expecting the same kind of a “tubey – warmish” sound signature with more power, added dynamics and better overall technicalities, due to the balanced circuit, but I have proven quite wrong.
Well at least regarding the first part of the above sentence, because the iBasso AMP14 is indeed considerably more dynamic and impactful than the AMP13 and definitely technically superior.
Not as hard hitting and rumbling as the AMP12 or the stock but close enough and certainly more than satisfying when large dynamic swings are needed or extra bass impact is desired.
The bass is very tight and controlled, exemplary layered with precise timing but not as visceral and meaty as in the AMP13 or even the AMP12.
The iBasso AMP14 is surprisingly crystal clear and transparent to the point that you don’t believe that it is a tube amplifier while it is very resolving, it has the most articulated mid-range and offers plenty of micro detail retrieval.
And don’t confuse that detail retrieval with terms like “analytical” because analytical it is not, the AMP14 resolves the finest details in the most natural way offering a joyous interplay between all the small particles of the music that get bonded together to form the whole picture.
Unexpectedly so for a tube amp, the iBasso AMP14 has some tendency to favor and highlight the upper-mids and the treble, there is plenty of energy and luminosity, it is a sparkling and airy presentation that is more reminiscent of the stock AMP rather than the AMP13 or AMP12.
In this regard the latter amps are more natural and realistic sounding in the upper part of the frequency range, especially the AMP13, which is smoother than the AMP14.
With the iBasso AMP14 you don’t get the tube warmness and smoothness of the AMP13 nor the same kind of relaxed and easy going nature of it.
The AMP13 has a more colorful and chromatically varied presentation, it is more analogue sounding, the notes appear to be loosely bonded with a longer decay but the iBasso AMP14 is lighting fast, has better definition and a sharper, fuller attack.
So, what exactly does the Nutube add to the sound that the solid state circuit of the stock amp can’t?
Well, it adds more weight around the notes and makes them sound rounder and fuller, there is also an excellent texture consistency from the top of the bottom, treble is as full sounding as the bass so you get more realism to the overall presentation of the music especially when acoustic instruments are involved.
The iBasso AMP14 excels into micro-dynamics and shading gradients while it is very open sounding and holographic at the same time.
The AMP13 focuses on a center image which then expands to reach out of the listeners head but in an less stereoscopic way than the AMP14 which sounds more diffused and grander while it has the leading edge when it comes to imaging and depth layering.
The iBasso AMP14 is of the rare instances, at least for a portable player, where the Focal Clear Mg sounded so expanded while already open sounding headphones, like the Sennheiser HD8XX, really shined with all kinds of music and especially large scale symphonic works.
The balanced line output
The balanced line output is derived directly after the dual DAC’s I/V stage without further processing.
This is pure undiluted sound from the heart of the chips with unbelievable fidelity and transparency.
And it sounds absolutely stellar with excellent audio quality, someone could argue that this is the true sound of the ROHM chip and it is something that you should definitely try.
From a technical point of view the lack of a voltage gain means that the level of the signal is limited to 1.8V which is lower than the 4V standard of the industry.
Thus said, I have hooked the balanced line output to my Kinki EX-M1 integrated amplifier and the Cayin C9 balanced headphone amplifier and I didn’t have to turn the volume higher for any type of compensation at all.
In the end
The iBasso AMP14 is a welcomed addition to the iBasso amplifier modules family offering the user one more option for fine tuning the sound of the DAP.
With an overall presentation that reminds a lot of the stock amp, the iBasso AMP14 is for all those who like a touch of tube magic without sacrificing absolutely nothing in technicalities, transparency and overall fidelity.
Copyright – Petros Laskis 2023.
Pros: + Same excellent technicalities and fidelity like the stock amp but with a more natural timbre
+ Very expanded and holographic soundstage with pinpoint imaging
+ Shines both in macro and micro dynamics
+ More powerful from the AMP13 with a fully balanced headphone output
+ Exceptionally low noise floor and minimal electromagnetic interference
+ Very low microphonic noise
+ Dedicated balanced line output with stellar audio performance
+ Plenty of accessories
Cons: – Not as dead silent as the stock amp
– Tube implementation is not as effective as someone would expect
I had a different experience with Amp14 compared to the others. First, it would not go nearly as loud as the other amp modules. There was not much difference using the L, M and H gains. Secondly, I found it much more bassy than Amps 11 and 13 and similarly tuned to Amp12 which has more bass presence. I preferred the tuning of Amp13, especially since I don’t stream so interference isn’t an issue. To me the tuning of the 23 is more natural.
The stock Amp maxes at 7.1V, AMP12 at 8.3V, AMP13 at 4.1V and this one at 5.2V so, yes it can’t go as loud as the stock or the AMP12.
If you have carefully read the review then should have noticed that I wrote that the AMP13 is indeed the most natural sounding.