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Metric Halo ULN-2 2d Expanded +DSP

Metric Halo ULN-2 2d Expanded +DSP

4.25 4.25 out of 5, based on 1 Review

The Metric Halo ULN-2 is a wolf in sheep's clothing. Its modest appearance, age and price can make it seem like perhaps not the best deal around, but dig in and you will realise that this box not only will make your life easier but that it is a DEEP piece of gear.

4th October 2016

Metric Halo ULN-2 2d Expanded +DSP by thermal

  • Sound Quality 5 out of 5
  • Ease of use 3 out of 5
  • Features 5 out of 5
  • Bang for buck 4 out of 5
  • Overall: 4.25
Metric Halo ULN-2 2d Expanded +DSP

First I would like to emphasise that I do not have much experience with high end audio interfaces - I am a hobbyist producer/mixer (although I do spend a lot of time on this hobby) and have been for 20 years. I upgraded from a modest Presonus Firebox which had been my companion for about 10 years. Did a huge amount of research before I ended up buying the ULN-2 - was planning on getting an Audient iD22 before a second hand ULN-2 showed up on my local "craigslist" for $800 or so. I jumped on it and am glad I did.

Now for some tech specs:


*2x analogue ins on separate XLR and TRS inputs (XLRs go to the mic pres and TRSes go to the DIs) - both types of inputs can accept line signals as well. Good dented gain knobs on the front in 6 dB steps up to 72 dB of gain, with additional trim knob for fine tuning. Separate +48V phantom power switch on both channels

*4x analogue outs, perfect for driving two sets of monitors. The "monitor" outputs have a dedicated volume control on the front of the hardware unit.

*Headphone output (duplicates the "monitor" outs but thankfully has its own volume control on the front of the hardware)

*2x Analogue sends and returns, enabling e.g. patching a stereo compressor into the signal path

*S/PDIF stereo I/O, optical or coaxial

*AES/EBU stereo I/O (although I believe you have to select either AES/EBU or S/PDIF, can't have them both at once)

*ADAT 8-channel I/O (if this is selected as the optical i/o, you lose S/PDIF via TOSLINK as physically there is only one optical in and one out, but you could still use coaxial S/PDIF in addition to ADAT. Also you can choose to have TOSLINK on the input and ADAT on the output or vice versa.)

*Nice input and output meters on the front of the unit

*Snapshot buttons on the front let you change the software settings (mixer routing, plugin chains etc) without touching a computer. There are 10 snapshot slots. This box can do a whole lot without being connected to a computer.


Oh dear, it is too much to list. Some highlights:

*The most important parts of the software (MIO Console) are the the MIO Mixer, its plugins, the Monitor Controller and the Recording Panel.

*MIO Mixer is a totally customisable digital mixer operating at 80-bit resolution, which is awesome because:

-You have 18 FireWire sends and returns which appear in the DAW as inputs and outputs - fantastic for summing in the MIO Mixer with Character (analogue circuit modelling) processing and returning to DAW to record the stereo mix. I get a better sound this way than bouncing within my DAW (Logic) - not sure if it is because my gain staging in Logic is off, which I do not believe it should be as I pay a lot of attention to avoid overloading plugins and busses - results are clearer and with better spatial imaging.

-You can route anything anywhere, you have inserts and aux sends, make as many mults as you want, parallel compression, jump out of a signal chain in your DAW to process with +DSP plugins in the MIO Mixer and return to DAW for further processing.

*The plugins generally have poor user interfaces (too small for my eyes!), but the sound is GREAT. MIOstrip is delicious on all counts - gate, EQ, compressor. MIOlimiter is also very nice, and if you need the flexibility of 12 type-switchable EQ bands, the MIOeq12 will give you that. HaloVerb is a good reverb and the Transient Control gives you possibilities reminescent of SPL's Transient Designer. As I have the +DSP licence I have access to a shedload of building blocks to build my own plugins (AKA "Graphs"). Have not gotten to this yet myself, but Metric Halo have included a few good examples of what can be done, such as the M/S compressor, M/S EQ and and parallel limiter. I have noticed there are some tasty distortion/saturation building blocks, so one day I will make some sort of parallel compressor/saturation graph...Did I mention the plugins run off the hardware and place no strain on the CPU of my computer? You can easily run a large number of MIOstrips before the DSP can't handle anymore. Reverb and delays are much more demanding, though.

I have to admit I use MIO plugins mainly when tracking (which is superb) - for workflow reasons I prefer to do all my producing and mixing in one place (Logic). Also a bit afraid of what could happen if I at some point do not have an MH interface anymore. I use the Character insert a lot though - when I am bouncing down tracks to save CPU I often do it through the MIO Mixer so I can stick a Transformer or something on there to add a bit of flavour. Works nicely even on the 2-buss.

*Monitor Controller: LOVE IT! You can set up key commands to switch between speakers, turn volume up and down, dim, etc...if needed you can also attenuate your outputs so that your levels stay consistent when switching between speakers (or between speakers and headphones), for instance. I am seriously digging this part of the package.

*Recording Panel: Records separate files based on which channels in the MIO mixer are armed for recording. I don't use it as I find it annoying to have to interleave mono files after recording, but apparently the recorder is extremely stable, so if you record live shows it is probably great to have.

Sound quality:
I certainly cannot blame the audio interface for poor mixes anymore! The Firebox was not good in the low end, which I did not realise until I upgraded to the ULN-2. It was like getting a new set of speakers with much tighter and more defined bass response. Mid and highs were also improved, as was the stereo imaging. I am simply loving making music and mixing with this interface. The quality of the onboard mixer and plugins is also outstanding.

Ease of use:
Gave it a 3 as the possibilities are so vast it's easy to get a little confused at first. However, now that I have "settled in" I am very satisfied. Tiny GUIs on the plugins are a major bummer, though. And if it were possible to instantiate the plugins from the DAW as well as from the MIO Mixer, the DSP processing would be much more useful.

Have you read the above? 'Nuff said!

Bang for buck:
It does cost a lot, but then again you get a lot. And the customer support is amazing! WORTH IT.

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