Hey all, my first time posting here.

I am currently moving from a hobbyist home studio to a semi-professional working environment, as I am starting to regularly work with clients or collaborators. I currently run with a (at the very least) 6 year old Steinberg UR22 mkII. It's served me well over the years, but now that I want to upgrade the rest of my gear I feel like it would be best to improve on conversion quality first.

In my research I've settled on two options: The new SSL18 or the time-proven UCX II by RME (The Audient id48 is also on my mind every so often). I'm mainly looking to invest in outboard gear and "better" microphones, so the more I/O that come with teh SSL 18 straight out of the box are appealing to me. I also simply enjoy the idea of having a piece of SSL gear in my studio.

On the other hand, RMEs Totalmix is said to be a pain to get into, but a big advantage once you understand it. Anyone who has experience with SSL 360?

By the way, this is all still very much in a home recording setting, so I won't be tracking e.g. a full live band on this setup.

Any thoughts?

buy both with a 100% return policy. do a shootout, keep the winner.

the 8 preamps in the SSL add a lot of value. you can put that savings toward buying quality microphones, which is a priority. you can buy external preamps for the rme. but will you? that adds to the cost and complexity.

the ssl gives you two headphone outputs, each with their own front-panel dedicated volume control. the rme gives you only one headphone output, with no dedicated volume control. the rme also gives you no dedicated control for monitor output. the rme doesn't even give you dedicated preamp gain knobs, which is ridiculous.

the ssl gives you one knob per function on anything pertaining to signal level, which is what you want. the rme gives you one knob per interface, which is as stingy as it gets. you will pay the price for this stinginess, as you will have to constantly push buttons and menu dive to perform basic, essential tasks. rme is charging you hundreds of dollars more, and you are getting so much less in areas of high concern.

the feature set is definitely better on the ssl, and the interface layout is much more intuitive. but to convince yourself, buy both and keep the winner.

Totally depends on whether you need mic preamps or not. One interface (SSL 18) has eight mic pre's with polarity. The other interface has 2 mic pre's and 8 line inputs. They couldn't be more different.

Also, the RME is $500 more.

If you're gonna be tracking drums, etc...where you need the features of the SSL...the answer should be pretty clear.

If you need lots of routing and monitoring go RME for the TotalMix flexibility.

If its just you and some overdubs SSL be fine.

Neither a bad choice.

1. Total Mix looks more scary than actually it is. Earlier I used all kinds of interfaces but at home my last interface was a very old school designed, software free, "hands on" SPL Crimson which I loved for it's "each function has got a dedicated knob or button" design. So if even I managed to get comfortable with Total Mix in a few days than anyone else can learn it easily. I wouldn't say that Total Mix became my favourite mixer platform, but it's totally mad how capable and flexible it is. (And with ARC it's also pretty comfortable to use, but more about that later.)

a.) First I watched this video:
https://www.youtube.com/watch?v=q647JUtop1A

b.) than RMEs official youtube tutorials:
https://www.youtube.com/watch?v=Zkxz...JSIBZC7_en5rck

https://www.youtube.com/watch?v=IdIxQkiV7H4

c.) and finally I read the manual.
After these steps it's GUI started to make a lot of sense, never felt lost or confused again.

(Sadly I've got zero experience with SSL 360, so I can't help you with that.)


2. If very low latency is important to you, than most probably the UCX ii is the much better choice. Other than RME your only other proper low latency option that I know of is the Presonus HD8. Just like RME, - to achieve as low latency as possible - the HD8 runs on in house developed drivers. This is from the recent SoundOnSound April 2025 Quantum HD8 review:
"Nearly all USB interfaces nowadays use Apple’s built-in Core Audio driver; with a 32-sample buffer, this usually delivers round-trip figures of around 7ms at 44.1kHz, plus whatever is added by the internal mixer. That’s unproblematic in most circumstances, at least as long as your DAW session leaves enough CPU resources free to handle the processing overhead of running with the lowest buffer size, but it’s still significantly less good. I was expecting the new Quantums to offer comparable performance, but I was pleasantly surprised to discover that Reaper reported input and output latencies of just 1.4 and 1.8 milliseconds respectively for a 32-sample buffer. Re-recording an audio click showed that although this reported 3.2ms round trip latency was not perfectly accurate, it was only out by about 14 samples, this presumably representing the delay through the mixer. A round-trip latency of about 3.5ms is thus achievable on macOS even at base sample rates. This may not be quite as good as the Thunderbolt Quantums, but it equals or betters pretty much every other interface I’ve tested, including other Thunderbolt models. Full marks to PreSonus’ engineers for not being content with ‘good enough’ on this front."

I've watched some videos and read the specs sheets of both the SSL18 and the HD8, and I couldn't find many reasons why I would pick the (way more expensive) SSL18 over the HD8 (other than the sexy look of the SSL ).
Plus as a huge bonus, compared to the UCXii and the SSL18, the HD8 is also much cheaper: at $800 it looks like a bargain. (Regular price is $1000 but at the moment it's on a $200 sale at Sweetwater.) It also comes with a Studio One Pro 7 perpetual license + 12 months Studio One Pro+ etc.

One potential negative about the HD8: I've read a few complaints about dropouts on early production HD8's so I suggest you to do some research whether that's already sorted or not.


3. If low latency is not such a priority for you than I wouldn't rule out the MOTU 828 (2024) and the new Audient ID 48 you mentioned.
Sam Inglis reviewed both the Quantum HD8 and the Audient ID48 in the recent April 2025 SoundOnSound magazine. He makes quiet a few comparisons there, I think it's worth you reading both.


4. Two more thing perhaps worth mentioning about the UCXii:
- the UCXii can be surprisingly hot. I'm sure it's because all of it's sophisticated functions need some serious processing and everything is cramped together inside it's tiny half-rack housing.
+ it's headphone output sound quality is much much better than any interface built-in headphone outs I've recently heard. It drives all my cans (Hi-X60, DT880, HD600, HD280, HD800) loud enough without any audible distortion. So unless you
a.) use some madly hard to drive cans;
b.) like to work at volume levels where your ears bleed;
c.) want more than one headphone outs
than you won't benefit much from an external headphone amp.


5. Your "constantly push buttons and menu dive to perform basic, essential tasks" critique is 100% valid, these problems you mentioned are real, but can be solved by the ARC:
adding an RME ARC USB Remote Control to the UCX ii is a must! In fact, without the ARC I would not have picked the UCXii, It is an incomparably better experience with the ARC controller. Yes, the UCX ii + ARC combo is a good 350 EUR more expensive than the SSL18, but it's Total Mix routing sophistication, it's Monitor/Room correction EQ function, it's exceptionally low latency, it's small size/portability etc. makes it a totally unique product. I would even argue that if you need and benefit from all these features than it's pretty great value.

https://www.youtube.com/watch?v=MQm-...tG0lI8G8PqzQl4

+ I also agree that the UCXii should have 2 headphone outs as standard. For now I had to sacrifice output 5/6 for a headphone amp to have 2 headphone outs.

I would add that Totalmix has a simpler mode (iirc it is called DAW mode) that hides most of the complexity for normal use cases. But I’d also say that if one decides to get an RME, it is well worth the few hours to wrap your head around Totalmix to make the most out of it.
And while the front panel is the opposite of “one knob per function” and rather useless, there is a Totalmix app for iPad which acts as a remote control.
Another thing with RME is that while the obvious feature/price ratio doesn’t always look good, I guess that one reason for the higher price is the long term driver support. You can still get current drivers for products that were released 20 years ago. With other vendors, you might need to invest in a new interface just because it doesn’t work anymore on your new computer in say ten years time, which negates the cheaper initial cost (not saying that will be the case with the SSL, but they haven’t been that long in the interface market either).
(But I agree that the UCX sorely needs a second headphone out…)
But as already said, best to test both if possible.

Great point. (As an example: the SPL Crimson 3 interface/monitor controller was released in 2017, already discontinued and is without any further driver support.)

You mentioned the ID48 - really good for the price…Pres are top notch, conversion excellent, and having inserts on all of the Pres is really a nice thing to have.

Three important points.

1. Buy RME because their drivers are class leading and you’re unit will be supported so that you’re great grandchildren can use it.

2. Buy RME because the build quality and sound quality are superb.

3. Point one again.

I currently have an RME RayDAT in my studio PC system and a Babyface Pro FS on my M4 Max MBP system - both superb interfaces. Total mix is brilliant.

I just sold a 20 year old RME Multiface. It looked like the day I took it out of its box (after 20 years of use) and I got back 50% of what I payed for it 20 years ago …. how many interfaces can achieve that.

and rival unit being considered by the OP uses the Theyscon worst in class driver under Windows.

Which is that, and what's the problem?

Thanks in advance.

I use RME and SSL in my studio.

I have a MadifacePro and two Alpha links with 24 Adda 24 aes i/o and 128 madi

It’s a good setup. Totalmix is easy to use. It’s an incredible digital patchbay and mixer

BUT in that price range

… take look at the Neumann MT-48

https://www.sweetwater.com/store/det...udio-interface


or Apogee Symphony Desktop https://apogeedigital.com/product/ap...phony-desktop/



The Neumann also allows for Dante and Ravenna for down the road.

With both you will have fantastic conversion that will last for decades.

Mostly the extra latency most systems other than RME have, especially with USB.

For people playing VIs it can make a difference.

If you’re not doing that - not so much.

I’m fully ITB and wanted good VI performance for both windows and macOS so I have no other choice but RME. Some manufacturers have double-buffered output latency on Windows but not macOS, for example. I needed something universally good.

I use heavy VIs and FX so if someone says “just use 96KHz and 32 buffer and no matter the driver the latency will be low” - no, that doesn’t work for CPU reasons.

Stability and high latency.

To get any kind of stability a large buffer needed.

Often twice that required for stable operation of comparable interfaces with in house written drivers.
And here I mean in house drivers from the like of Tascam.
Not RME

This is a great discussion, and I am in the same boat, but the twist is that I will be recording multi-channel simultaneous audio. I will demote my Tascam Celesonic and MAudio Profire to ADAT duties and have enough XLRs that way that Mic Pre’s aren’t essential. I can patch my synths to the new interface.

When I started this journey, I was going to go Cranborne with 500 series pres etc., but decided to step into that world with a Heritage HA81EQ rack unit. I haven’t ruled the Cranborne out but after a lot of research am kind of convinced that driver stability and support - with good RTL - are paramount which has boiled it down to the MOTU 828 and UFX II (I need the two ADATs). I had strongly considered the HD8 as well especially for the price and it has some compelling features, and I am using S1 Pro 5. I do like the built in DSP for standalone mode though and have determined that the MOTU just edges out for customer support aspect. I am real close to placing my order. If a used UFX II appeared for $1,800 I would probably jump on it. Still torn. BTW I will also be upgrading to M4 Max Studio.

Thesycon is the most popular generic driver for windows.

Used by many companies who don´t want or can´t write their own.

And yes, the performance is rather underwhelming

Is this problem the same on Mac and PC?

Curious as its never come up before and I use a hell of a lot of different boxes.

No.
There´s no class compliant for PC, hence the need for something like Thesycon.

But on my Mac, I prefer RME drivers over class compliant, too

It depends on what you’re doing, see my post further up.

On Macs, class compliant doesn’t mean all interfaces doing that have the same performance. It just means they need no drivers.

Of course, not everyone needs the lower latency.

Hmm my SSL box does need a driver, is that not one of the dodgy ones then?

I use it for virtual keyboards and no problem with latency.

If it’s OK for you then you’re fine. The same box on a Mac has higher latency, someone tried it in the latency megathread

Hence my need for RME, it doesn’t matter what the OS, it’s fast and reliable.

MOTU on windows has 2x the output latency, on Mac the drivers are way better.

Another example of inconsistency.

Some other vendors are only Mac if you want the best experience - so those were out for me too.

I needed something that works great on both OSes.

But I use it with no issues on both Mac and PC.

Bit confused now...

If you have no issues then you’re fine.

With RME I can set it to a 256 buffer and my latency is OK - which works for heavy on CPU sessions I have.

I have tried other interfaces and I have to drop buffer to 128 to get the same latency, and then my CPU goes haywire.

That’s what I mean.

RME Digiface USB + SSL Alpha 8
(hooked upto RME via ADAT)
Priced between the two options you've listed.
Gives some SSL gear to satisfy GAS.
RME Driver and Totalmix capabilites.

That sounds high. I run RME UFX at 32 on an ancient rubbish laptop.

SSL latency was about 3.5ms average.

You don't get latency with RME just phasing

Yeah if I use 32 buffer on what I do I can’t even play a single note

how many channels of I/O do you need an how many mic pres?

if you want to track drums than an interface like the SSL that comes with 8 pres is a plus cause it gets you going fast.

if you are mostly recording 1-2 channels at a time and want to add a few outboard preamps anyways than you don't need/want 8 pres anyways.

totalmix seems overwhelming at first but its not hard to grasp at all and very powerful and flexible. also it's quite handy that one can use any midi-controller as a monitorcontroller (or their arc-remote) and don't have to reach down/to the side to the rack to the interface.