Astell & Kern A&ultima SP1000M

GUI and Open APP Service.

The GUI of SPKM is identical to the original SPK, thus I refer you to read my original SP1000 SS/CU review where I already covered it in depth here.  The SPKM interface is as fast and responsive as the original SPK, and yes, the Parametric EQ is still an eye candy with a very subtle sound adjustment since, according to A&K, they put a lot emphasis into the tuning of the original sound signature of their DAPs.

I’m sure there are some other tweaks behind the curtains, perhaps optimizing some performance, but the first noticeable change is the Floating Back button which can be easily disabled by dragging it to the middle of the display or enabled/disabled in the Settings menu under Input Method.  The button itself is floating and could be moved to anywhere along the left/right sides of the screen.  You still have a Home touch button in the center under the visible part of the display, and when browsing A&K menus and settings you will find Back button at the top to go to the previous screen.  So, why do we need a Floating Back button?

The answer to the question could be found here, where Astell & Kern goes into details about their new Open APP Service feature which is going to be implemented in all of their Android 6.0 based DAPs, such as SP1000 SS/CU, SP1000M, SE100, and SR15.  While SP1000M introduced it as a teaser with a new DAP release, a week later the firmware update was pushed to SP1000 to enable Floating Back button and Open APP Service which currently supports: Amazon Music, Spotify, Tidal, Sound Cloud, Pandora, Melon, Bugs, Music Mate, AWA, QQ Music, KK Box, and more supported services coming soon.

Now, back to the question of the Back button.  When you start dealing with Android apps, in many cases you do need a Back button for navigation, and now you have one which going to come in handy when dealing with streaming apps.  While Astell & Kern offers a built-in Tidal and Groovers+ services (without off-line storage support), for a long time their customers been asking to add Spotify and other streaming services.  A&K latest DAPs do run on Android, but it’s a heavily modified closed OS without access to Google Play.  In a way, it’s a blessing for a manufacturer to keep DAP performance optimized since you don’t have to worry about customers installing and running other unstable apps.

Now with Open APP Service you have more freedom, but the list of allowed apps is reasonably limited.  And when you decide to install a non-blacklisted app, you need to download APK file (use a site like, copy it to Open Service Folder located on internal storage, go to Services on the DAP, and when you see the app being recognized and listed in there – click to install it.  Keep in mind, you will have to install Tidal apk if you want off-line downloads.  Also, installed apps will not be updated automatically since you are not running Google Play.  You will have to keep track of app updates and manually download and install new versions.

Since both SPK and SPKM will have access to Open APP Service, neither one has an advantage when it comes to streaming apps.  Even the difference in internal storage doesn’t matter since off-line downloads can be stored on external microSD.


Sound comparison.

Without a doubt, many will be curious how does SPKM sounds in comparison to SPK.  In this test I had both DAPs side-by-side playing the same song, using the same SE or BAL output (depending on cable termination), volume matched for consistency with the same pair of IEMs.

I took notes when listening out of the box and after a few hours, and then let SPKM play in a loop for about a week before making the final judgment about the sound comparison.  A lot of manufacturers recommend burn in, especially for the benefit of capacitors, and I’m glad I did it here because there was a noticeable change in the treble tonality before and after.  Before the burn in, out of the box, the treble was a lot smoother, still extended but with less sparkle, giving the overall tonality a warmer and smoother feeling.  I also heard similar impressions from people who attended RMAF’18 where SPKM was introduced to the public with fresh units on the display.  After the burn in, treble opened up, nearly matching the controlled sparkle of the original SPK.


Here is how I hear SPKM vs SPK.  SPK has a more holographic soundstage with a wider expansion.  Bass is nearly identical, from sub-bass rumble to mid-bass slam.  Lower mids are just a little slimmer in SPK, while SPKM has a slightly fuller body, though the difference is subtle.  Treble is also nearly identical after the burn in.  When it comes to sound performance, these are nearly identical with the same resolution, sound layering, retrieval of details, bass impact, and upper mids/treble presentation and tonality.  The most noticeable difference is in soundstage expansion (SPK is more holographic), and lower mids thickness (SPKM has a slightly fuller body).

In this testing I was using CFA Andromeda, UM Mason V3, Oriolus Mellianus, and 64 Audio U18t IEMs with a variety of instrumental, classical, pop/rock/EDM/acoustic lossy and lossless tracks.  In every case I had to volume match since SPKM balanced output has a little more power, making it more efficient where I had to adjust volume by 3 clicks down.  In every case I found SPK soundstage to be more holographic/wider, and only in case of Mason V3 I found SPKM treble to be a little smoother.

Furthermore, since we are talking about the sound and I already mentioned about SPK fw update which aligns it now with SPKM, I also noticed no changes in the sound of SPK after the update.  Obviously, I can’t do a true a/b blind comparison since I don’t have two identical SPK units with different FW loads.  Also, you can’t go back in FW after the update.  The comparison was done by memory where I listened before and after the update.  But in case of FW 1.08 to 1.10, I didn’t hear any drastic changes in SPK.  There could be some subtle differences, but it’s hard to tell.



Lately, going bigger and heavier seems to be a new norm for flagship DAPs, getting to the point where some are starting to feel more transportable than portable.  It’s fine for a home use where you don’t want to be tied up to your desktop, and it’s very convenient when listening to high res music at work, on a business trip or vacation, or during a long commute to/from work.  But walking around with a larger size 350-400g DAP in your pocket will not be comfortable for everybody.  As a result, people look for smaller devices, finding the best compromise between the size/weight and the performance.

Surprisingly, while SP1000M cuts corners in the size and the weight, its sound performance wasn’t compromised too much.  SP1000M size is smaller and more comfortable for one-handed operation.  Its weight is down to almost half of SP1000 SS/CU.  Its screen is smaller, yet still with the same resolution, and large enough to view and to read everything clear.  It still features the same two flagship DACs and fast processor.  Optical output and external amp docking are removed since it’s targeted for a more portable pocket use.  Internal storage is reduced from 256GB to 128GB, which could be under Cons for some.  And there is a sweet reduction in price from $3.5k to $2.4k.  But the most important one, with an exception of a wider soundstage perception in SPK, the rest of SPKM sound performance is very close.

In my humble opinion, if you already have SP1000 SS/CU – I don’t see any reason for an upgrade, unless you are really bothered by the size and the weight of it.  And if you have been eyeballing SP1000 for a while, now you have a chance to save money without sacrificing much of the performance, with an exception of a few differences which some might not even hear.  If you want the top dog, SP1000 SS/CU is still A&K flagship and SP1000M is not taking that crown away.  But SP1000M is pretty damn close, even with additional benefits if you need a more portable DAP.  And of course, both will have the latest FW with Open APP Service.



32 thoughts on “Astell & Kern A&ultima SP1000M

      1. Certainly, but I don’t have access to se100. Also heard from other trusted sources, it’s technical performance is nowhere near SPK. But that’s other peoples opinion 🙂


  1. Personally, I preferred SPM compared to SPK due to the subtle warmness and the extra body on the note. Was always a fan of WM1Z but I find the resolution/clarity is lacking (Without any mod, never tested one with them). SPM will just fit right in my pocket and I think others who has the same dilemma might consider this option 🙂


  2. Hi, I own the SE100 and love it, but I am planning to exchange it for the SPKM in a few days. I am a little surprised to read the SS is not as holographic on the spkm vs spk, all the other reviews I’ve read say the spkm sounds superior. I use it with the Shure SE846, balanced out with Litz silver cable.


    1. Hmm, I did write in my review that SPK (SP1000 SS) has a more holographic soundstage in comparison to SPKM (SP1000M), so you could have misread it? I’m not aware of any official SPKM (SP1000M) reviews, only a few impressions from the show in a noisy environment and from reporters. Keep in mind, we hear things differently and use different headphones, not everybody hears the same. But I did spend a dedicated time with SPKM to give it a good listening over many hours with different headphones. Plus, just think about it, why would A&K make a much cheaper product to sound “superior” and to kill it’s flagship? 😉


      1. hahaha, I knew you gonna quote this article, yeah, we talked about it in SP1000 thread on HF for awhile. Besides my official review/comparison, there are only 2 other references peope bring up. Whathifi posted their impressions specific to SPKM and under a sound description only mentioned how a few songs sound played on SPKM. No comparison or detailed sound analysis, just an impression, right?


    2. I might be late to the discussion but here my unbiased thought on it and shall serve as personal reference only.

      You cannot go wrong with both. Its a matter of preference and music genre. Tested them and they have their own pros and cons. This was done under blind test with the help of 3rd parties. I find that the “holographic” which i presume is “soundstage” is part of the circles as well.

      SPKM = (More personal and intimate with hint of warm) and SPK = (Wider amidst very little and more reference sounding – remind me of hugo 2). Thus if you are a classical person, SPK will be your choice and if you are like me who like warm and intimate feeling (WM1Z fan base), get SPKM.


      1. Thanks for that. Just want to point out that the spkm on balanced out has slightly higher SNR, lower clock jitter and lower THD . Just saying.


  3. Hi Alex.
    I know you don’t own the spk cu, but would you say the sound of the sp1000m leans towards the cu version more so than the ss version?.Is it right to say that sp1000m is just as warm as Cu ?. Would you recommend a warmer monitor to pair with sp1000m, say the EE phantom?


    1. I can’t make the assumption about CU version. Throughout fw updates, SS version got warmer due to smoother treble rendering. I don’t know if CU got warmer or more revealing, or just more resolving… SPKM pairs up great with any signature monitors. It just makes the sound more natural, more organic without taking away from resolution. Not familiar with Phantom, but heard it is on a warmer side. Probably should pair up well with SPKM. I also heard Phantom hisses with man sources, while A&K is known to be hiss free.


  4. Thanks for the review. I read some other ones concerning sp 1000. Thanks for your insight. I was wondering if you could advise in something. I have ordered 64 audio U18 and currently have A&K 300. But I want to upgrade to spk copper or perhaps spkm. I do love a bit warmer ( full bodied sound) but also love the wife stage where you can hear all the instruments what combo would you suggest to complement the u 18 ?

    Thanks a lot


    1. I only heard SPK CU for a short time with early fw releases, and found it to sound warmer in comparison to SPK SS. If you are not trying to save money (SPKM is cheaper, of course), SPK CU will probably be better for sound sig you are after.


      1. Hello , I have last question Some reviews stated that the 64 audio (U18) universal IEM sound noticeably worse that the custom fit. Because of fit ( seal) issues the sound signature was not as good as in the custom fit models. Did you have the same observation with any of the models ? I am thinking of getting custom tips from Custom Arts for the U18 as it is too late to change my order. Would you say that that might be better ? Thanks a lot for your time 🙂


      2. the only difference I observed in the past between 64audio U12 and A12 was the bass impact, with CIEM having a lot more vs universal version having “variable” amount which I can control by switching between different eartips (better seal – more bass).


    1. U18t is my favorite iem. But I do use the largest eartips, went through a number of different ones until I found the right fit for MY ears. The right fit is a key to a perfect sound.


      1. Hello
        Would you mind sharing what tips you found to work best for you ? I have quite small ears so I will have to investigate. Thanks


      2. I reviewed dozens of IEMs, saving eartips from all of them, and also got dozens of eartips from ebay and from, so I go trough everything to find the biggest (large or extra large) pair of eartips to give me a seal. It’s easier with small ears to get a seal. While a struggle with large earcanal opening 😉


  5. Hello,
    I know you had a chance to listen to both u18t and U12. The base in the U 12 is what I really liked the most and there was also more body to the vocals comparing to the U18. I listened to it on my AK300. Would you say that the bass and mids on the U 18 improve on the spk copper ? I am still debating if I did the right thing chosing the U 18. I loved the sound stage and the clarity in really busy recording ( lots of instruments). In those situations I couldn’t listen to those tracs on U12 as they seemed too chaotic. But on U 18 they were enjoyable. But I also loved the base on the U 12. So I wonder with the much better source they would sound Fuller ?
    Thanks a lot for your time. 🙂


  6. Hello. ,
    Thanks a lot. I totally agree with your reviews. Except I felt the U 18t had less bass than U 12t but it may have been due to the seal problems. I had both home for several days it it was so hard for me to decide. Each was good at something. But if seal was a problem than the U18 shouel be the ones. If it will have a similar amount of bass that they should be perfect.


  7. Hello!
    I found your review very informative, however I have one question about your comparison of SPK and SPKM after fw update. I will quote: “I also noticed no changes in the sound of SPK after the update.” This description is double-edged for me, I don’t understand, is SPKM has no changes in comparison to SPK after SPKM’S fw update or is SPKM has no changes in sound before and after the update?

    Thank you!


    1. Sorry for the confusion, it was more of a side-comment specific to SPK only and its own FW update which enabled side-loading of apps (thus aligning it with SPK M in terms of streaming capability). I meant it that I didn’t notice any sound changes in SPK after updating its own fw…


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google+ photo

You are commenting using your Google+ account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s