Comparison – SP1000 CU (fw 1.06) vs WM1Z (fw 2.0).

No discussion of SP1000 SS or CU would be complete without comparison to Sony WM1Z DAP since these are top choices for many audiophiles looking for the summit-fi portable source. But besides a difference in chassis material and the weight (SP1k SS: 388g, SP1k CU: 418g, WM1Z: 452g), there are also noticeable sound differences.

Based on my testing, I hear a very similar soundstage expansion between these two. Also, WM1Z has a little more warmth in tonality, deeper and beefier sub-bass with more rumble, and a stronger mids bass impact.

SP1000 CU bass is a little tighter, has a little less sub-bass quantity, and a little shorter decay in mid-bass. Furthermore, CU has a little smoother treble, while WM1Z has a little more sparkle in treble. Keep in mind, this is all based on a relative comparison, doesn’t mean that CU treble response is rolled off, just that in comparison to WM1Z while playing the same hi-res track and using the same pair of hi-res IEMs, I hear a little less treble sparkle with CU.

Both have a warmer tonality, but WM1Z just a little warmer. And, as already mentioned, they have some differences in bass presentation with WM1Z sub-bass having a little more rumble and mid-bass hitting a little harder, while SP1000 CU having a little less sub-bass and overall bass being tighter and a touch leaner. Also, WM1Z lower mids are a touch leaner in comparison to CU, making it less congested.

Comparison – SP1000 SS (fw 1.07) vs WM1Z (fw 2.0).

Considering tonality changes of SS1.07 update, I think that it also makes sense to compare it to WM1Z.

The first thing I noticed right away is a very similar soundstage of SS1.07 which is on par with WM1Z. Per my previous comments, SS1.06 was wider.

Also, their tonality is not too far off, with WM1Z being just a little smoother with a fuller body. Maybe I’m splitting hairs here, but even with subtle differences I find the scale of smoothness to go up from SS1.07 < CU1.06 < WM1Z. And as before, WM1Z has more sub-bass rumble and a little stronger mid-bass. Plus, WM1Z still has a little more sparkle in treble.

SS1.07 has an excellent sub-bass extension and fast mid-bass slam, but the quantity is a little more neutral in comparison to WM1Z. Also, I hear SS1.07 treble a touch smoother. Upper mids are very similar while lower mids of SS1.07 are a little more neutral in comparison to WM1Z.

Here, the main difference is in bass and treble presentation. 1.07 update made SS to sound a little smoother, with more body, but still less in comparison to WM1Z. WM1Z has more emphasis on sub-bass and mid-bass and a little more sparkle in treble when compared to SP1000SS, while both have an excellent bass and treble extension.

Conclusion.

Astell & Kern A&ultima SP1000 is not a new DAP, and it was already covered by many reporters a year ago when it was first introduced. But even to this day I still can’t find as many in-depth reviews going over the sound details, including lack of comparison between SS and CU versions. More people talk about chassis material, trying to justify how conductivity property of stainless steel and copper frames (connected to the circuit ground) will affect the sound. Also, some speculate how firmware updates with optimization of background processes could have an indirect effect on sound quality. I approached this mini-review by treating each DAP as a black box, only focusing and describing what I hear.

Just like with premium headphone cables, I don’t expect everybody to hear the same level of sound difference between SS and CU or between firmware updates. Obviously, it’s a subjective opinion. But I do hear SS and CU models to have their own unique sound characteristics, as I described it in my write up above. And especially with fw updates, unlike WM1Z where you can go back’n’forth between fw1.2 and 2.0, once you update to fw1.07 you can’t roll back to the previous version, so please be aware of the changes. In reality, you can’t go wrong with either of these DAPs, but if you are trying to decide which one to pick – I hope my review will help you narrow it down to your DAP of preference.