ATC SCM 25/45, KII Audio Three, Unity Audio Boulder MKIII, or PMC 6-2?

I am currently in the process of upgrading my setup. I wonder if anyone here has had any experience with the models I mentioned in the post title. If so, have you had any good or bad experiences, given the price point of these monitors? And if budget wasn’t an issue, which monitors would you choose?

Thank you for your time!

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Hey Mikey,

That is always fun to be looking at monitors of that level for their intended uses!

I bought into the work and ideas of Unity Audio and Kevin and the team there are just stellar - that I can vouch for. My system is built upon:

Unity Boulder MKII’s +
Remoted amps in the Boulders

It’s incredible - the Boulders alone on their own are jaw dropping to listen to and use for more revealing work. End to end they do not skimp on a thing, and sometimes it feels like you even have a very unique custom system.

Go read on the BABE’s there was a SOS review that was stupefying and it led me to go this route with their approach to DSP and 3.5 way system or whatever it is?!

Personally, I would say so much of this is not subjective as much as its what size room + what amount of cubic volume is your room + how is your room treated + how will it be “tuned” ala what will be tuned.

But -

+1 Unity

Best -


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Thank you, Dayz! I actually currently own the Boulder MKIII. I do like them a lot, I just feel at times they don’t quite do it for me in the low end. I actually purchased a Trinnov ST-2 pro to help with the monitors. It did definitely help in many ways, but, I want to ensure that what I currently own is exactly what works for my ears. At the NAMM show, I heard a pair of Kii Audio Threes. They made me feel quite excited about what they were emitting. However, it is NAMM and not quite the optimal listening environment. I am just reaching out to see if anyone else has had experience with any of these monitors and maybe they could help me lean down a certain path. So far, you are making me reconsider switching it up. haha. So, thank you!

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I owned or tested a couple of the speakers you mentioned. And my personal findings are…unfortunately, it’s the room and your taste (in what you want to hear from a speaker), that decide what will work for you. If you have any chance of getting test pairs for all of them, try them in your room, only then you will know for sure and not keep that ‘what if’ nagging in the back of your head!

For example, I’ve had the Kii for a couple of years and really liked them. My two main problems: I couldn’t get them loud enough in our large room (clients on the couch in the back wouldn’t feel it). In my smaller room (about 25-30m2) that was okay. The second problem were the low mids & the higher low-end. I do mostly acoustic music, drums, bass, guitars, vocals…often lots of low-mids that I need to hear clearly. As great as they are, I always had trouble hearing it they way > I < wanted to hear that area, with lots of low-mids. That’s why I initially said ‘taste in what you want to hear’. For electronic music or rap, that wasn’t as much of an issue, especially if you work with already great sounding VSTi and samples. The solution to both problems may have been the extenders, also to get more low-end out but since they cost crazy money, the Kii went and the ATC came in.

After hearing ATC50s at a friend’s mastering studio, I got active 20s with a JL sub and they work great in my small room. However, as with most ATCs, without a sub, the 20s sound slim (and didn’t work in that large room either). A couple of years ago, I’ve had a chance to test 25s (not the new ones) against the 20s and, in my smaller room, I even prefer those a tad for the low mids, also without the sub. In the large room, it still would have needed a sub but I preferred them over the Kii for sure. The newer 25s are probably even nicer but that’s just a guess. In the end, I didn’t sell the 20s in exchange for the 25s though. They work and, to sell them, raise more money, exchange speakers and get used to them…too much hassle for a very small improvement in that room.
A friend had 25s too and owns the Kii and he sold the 25s but kept the Kii. It’s taste and what you want to hear…

Over the years, I’ve tested about a dozen speakers in my rooms, also new Genelecs, Dynaudio, Amphions, Events, Munroe, NS10s, Auratones etc (we also have Geithain, Quested here in the larger rooms), and by chance, when I wasn’t even looking for speakers, I got to test a pair of Neumann KH150 in my smaller room. They may not look inspiring and might be even expensive for what they are but, in that room, without a sub, they are the only pair I would need (especially with the mic/room treatment).
I don’t recommend that you check them out but, to bring it back to the beginning of this essay, you have to try the speakers you’re interested in, in order to really know what you can get from them in your room. And who knows, maybe an odd-ball will work best for you. Good luck testing!


Hey sorry for delay replying - so what did you end up doing? anything?

Try adding the BABEs in with your Boulders since you got em! That is why Kevin and crew developed them…


Neumann’s are or should be more of a go to then they are despite anyone’s personal preference IMO - they are all that good and crafted amazing, and they have a range price point wise. And I think like the various sizes of Genelec’s they overdeliver full speaker range in small amounts of physical space etc.

Cool write up about rooms and sizes and all that, that surely is a huge aspect - the cubic size volume problem.