After the initial listening to L6, I wasn’t too impressed because I found the sound to be thinner and brighter and the bass was too neutral for my taste. I gave it a week of burn in, thinking maybe it will fix the problem. The sound improved, but I was still on the fence when listening to L6 with U18t, which is a low impedance iem I use during my sound analysis. I set L6 aside and came back to it a few months later after I was done with a round of my recent reviews. It was puzzling, especially when I tried a few other iems, all with balanced terminated cable, and found a common trend of attenuated bass and thinner upper mids with a brighter treble. Only after I saw the spec on Penon Audio I realized that L6 balanced output has 4.4ohm impedance!!! High output impedance, which is fine with most of the 32ohm and higher iems and full-size headphones, was messing up the tonality of my low impedance balanced cable terminated IEMs. Once I switched to SE output, which has 2.2ohm OI, I got back everything in sound I was missing.
After trying a dozen of IEMs and full-size headphones, I can conclude that L6 has a very neutral signature with a highly resolving sound and a tonality tilted more toward a brighter and more revealing side. It has a deep low-end extension and an overall bass with more focus on accuracy and layering, rather than texture or warmth. And the same with a treble extension, where the only limiting factor is the tuning of headphone drivers.
But I think the strongest part of its performance is in mids, with a very delicate layering and separation of every instrument and vocals, as well as vertical expansion of sound dynamics. The focus here is more on precision rather than naturalness.
The same goes for soundstage expansion, which is wide and deep, and has a very accurate imaging with a precise placement of instruments and vocals. There are a few other DAPs where the soundstage width was a bit wider, but in terms of imaging and layering/separation of every sound – it was on par with the likes of SP1000, WM1Z and DX200Ti.
When comparing 2.5mm SE vs 3.5mm BAL, aside from the obvious difference of 2.2ohm (SE) and 4.4ohm (BAL) output impedance, you can hear BAL output having more power, requiring to lower the volume by about 5-6 clicks when switching from SE to BAL, but the tonality and the soundstage expansion were identical. I was more surprised about the soundstage being nearly identical, meaning the BAL output only contributes to additional power. Considering output impedance difference, I would suggest using SE output with lower impedance multi-BA and hybrid IEMs, while using BAL output with higher impedance iems/earbuds and full size headphones.
I was using U18t w/Horus with 3.5mm adapter from L6 SE port, volume matched in every case for a consistent comparison. Also, used Andromeda with each DAP volume down to zero to see if I can hear a hissing. Due to Andro sensitivity I find this pair up test to be useful, but please keep in mind that just because I can hear some level of hissing under these test conditions, doesn’t mean the source has a noisy background.
L6 vs A&K SP1000 SS – soundstage depth is nearly identical, while SPK width is more expanded. Relative to SPK, L6 bass has just a little less sub-bass rumble and a touch less mid-bass impact. Mids and treble are nearly the same, especially a lot of resemblance in treble where I found both to have a more neutral organic tonality. Just keep in mind, I’m comparing to SPK SS with the latest fw which has a smoother tremble. Also, both have a very similar layering and separation of the sounds, and a similar vertical dynamics expansion. On a technical level, there are a lot of similarities between these two. With Andro at volume down to zero, both have a little bit of hissing, but SPK is a touch lower.
You can use both DAPs as USB DAC, connect both through LO to external amp, use as transport to drive external DAC/amp. Internal storage varies with L6 (32GB) and SPK (256GB), but both could be expanded with uSD card. Also, both have a touch screen, though L6 is limited. Both have a mechanical volume wheel and hw transport buttons. L6 uses micro-USB while SPK uses a faster usb-c. SPK also adds Bluetooth w/aptX HD and soon will support streaming apps (though wifi and sideloading), while L6 only limited to audio playback. Also, both have 3.5mm SE and 2.5mm BAL headphone outputs, but L6 OI is a lot higher (that’s a negative point for BAL out). SPK has nice looking EQ which doesn’t adjust sound much, while L6 only has EQ presets but not adjustable EQ.
L6 vs Sony WM1Z – soundstage expansion is nearly the same, with 1Z reaching out just a touch further out, and width being not too far off, though 1Z is a little bit wider. With bass, 1Z has more sub-bass rumble and a little stronger mid-bass impact, and its bass feels more analog and textured, while L6 bass is little a faster and tighter. When it comes to mids, L6 is more neutral and a little more revealing while 1Z is smoother and a touch warmer. Also, with treble I hear a little more sparkle with 1Z. Their technical performance is almost on par, maybe with L6 having a touch better sound layering. With Andro and volume down to zero, both have a slight hissing, with L6 having a touch more.
1Z has 256GB of internal storage, Bluetooth w/LDAC support, but it lacks Line Out which L6 does support. L6 has only 32GB of internal storage and no BT. Also, there is nothing that could be done about limited L6 touch screen functionality, while no issue with 1Z. Furthermore, 1Z has a full EQ and a handful of DSP effects, while L6 only has EQ presets. L6 uses 2.5mm BAL while 1Z is 4.4mm and has a lower OI.
L6 vs Lotoo PAW Gold LPG – soundstage expansion is nearly the same, in both width and depth. L6 bass is less aggressive in comparison to LPG deeper sub-bass rumble and stronger mid-bass punch. Also, in comparison to LPG, L6 mids have a little more forward presentation, while LPG has more sparkle in treble. Both exhibit great dynamics expansion, and excellent layering and separation between the sounds where you can almost “hear” the air between the layers. With Andro and volume down to zero, there is slight hissing, with LPG being stronger.
LPG has no internal storage, only SD card, while L6 has 32GB of internal and uSD card. L6 also has USB DAC functionality, LO, and digital out, while LPG has only LO. Plus, LPG has small non-touch screen and all-button controls, while L6 does have a touch screen with a partial touch swipe functionality. One big advantage of LPG is its Parametric EQ, while L6 only has EQ presets.
L6 vs iBasso DX200Ti w/amp8 – while soundstage depth is very similar, Ti with AMP8 has a wider soundstage expansion. Starting with bass, Ti has a deeper sub-bass rumble and stronger mid-bass punch, with a more analog quality bass, while L6 bass sound more neutral in comparison, though got to keep in mind AMP8 which has extra low-end emphasis. With mids, I hear Ti being a touch smoother and more balanced while L6 has a slightly more forward presentation with brighter and a little more revealing tonality. Treble is the same. You can hear Ti having a fuller body while L6 is more neutral and a little brighter in tonality. With Andro, both have a little bit of hissing, with L6 being just a touch stronger.
Both have touch screen, though L6 is limited, both can be used as USB DAC, have LO, SPDIF out. The big difference is iBasso modular design and full Android interface with BT, WiFi, and access to streaming and other apps. Plus, 64GB of internal storage (Ti) vs L6 with 32GB.
L6 vs L5Pro – nearly identical soundstage expansion, maybe with L6 being a touch wider, but overall, it’s very similar. With tonality, I hear L5Pro being smoother while L6 is a little more revealing. Upon closer listening, I hear L6 bass being a little faster and tighter, L6 mids being a lot more resolving and with a better layering and separation of sounds (making L5Pro sound flatter and more congested in comparison), and treble being similar in tonality, just more refined in L6. With Andro at volume zero, L5Pro has a noticeably higher level of hissing in comparison to a milder hissing with L6. L5Pro is not very friendly with sensitive IEMs.
Regarding functionality, these are nearly identical, except L6 now adds vertical up/down swiping, balanced output, and working USB DAC (though need to check if L5Pro had any fw updates). The only thing I do miss from L5Pro are assignable C1 and C2 custom shortcut buttons. But at the same time, now the headphone ports are at the top, so you can place L6 in a pocket and connect headphone cable at the top while controlling the volume next to it.
L6 vs LP5 Gold – very similar soundstage expansion, with LP6 being just a little bit wider. Also, nearly the same signature and tonality, just with LP5 bass going a little deeper and being more analog/textured in comparison to L6 bass being a little bit more neutral and tighter. Mids and treble are identical. Also, very similar technical performance with both having a very resolving dynamic sound and excellent layering and separation. I always enjoyed LP5 sound performance, just wished it would be more pocket and user-interface friendly, and L6 is the answer to this wish.
In terms of GUI and functionality, it’s night’n’day in comparison to L6 where LP5 is very primitive with a few display lines in a small round non-touch screen, and only 5 buttons with d-pad type of controls. Don’t get me wrong, LP5 is very unique, but in a boutique way with a limited GUI.