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Metric Halo LIO-8

Metric Halo LIO-8

4.6 4.6 out of 5, based on 3 Reviews

High definition professional Firewire 400 audio interface for the Mac.

17th December 2011

Metric Halo LIO-8 by asenna

  • Sound Quality 5 out of 5
  • Ease of use 4 out of 5
  • Features 5 out of 5
  • Bang for buck 5 out of 5
  • Overall: 4.75
Metric Halo LIO-8


The Metric Halo LIO-8 is a scalable, upgradable and professional Firewire based audio interface. When looking for a true upgrade from my Apogee Duet and Digidesign 002R, I eventually settled on the LIO-8 as the true winner in feature set, build quality, sound quality and truly remarkable capability. It is a high definition unit with record settings from 16 bit 44.1 kHz all the way to 24 bit 192 kHz. Also equipped with on board DSP capabilities and software functionality, the LIO-8 hits on all cylinders.

The Box

Light and only 1 rack space, the LIO-8 is deceptively deep. It is something like 14 inches deep. The electronics are housed in a super rigid shell which dismantles with very few screws. The LIO-8 can be powered by industry standard camera batteries or via an included power supply. It connects and can daisy chain Firewire 400. It can operate with or without a computer.

The unit has 8 inputs and 8 outputs wired to Tascam spec'd DB25 connectors. It has 3rd generation AD/DACs on all I/O and an additional set of 3rd generation converters on the headphones output (lovingly labeled "Cans"). It also sports a DB25 connector for balanced sends for further flexibility. There are two DI connections on the front of the unit that automatically route to line in 1 and 2. If you have another source going in through the DB25 connector into 1 or 2, it will actually mix both signals together. Kind of an interesting choice given that most companies make it an either or kind of choice. There is also a DB25 connector for AES/EBU digital connections in addition to the MIDI, Woodclock and SMPTE I/O.


Looking at the back panel one notices a blank slot labeled "Mic In" where the optional mic preamp upgrades begin. You can install up to 8 preamps, or 4 at a time, in the LIO-8 if you find that mere line level conversion isn't going to do it for you. The installation of the mic preamps is very simple and can be done at home with a couple of tools anyone who even think about buying this should already have.

The LIO-8 is also +DSP enabled with a small bundle of plug-ins that are processed with Metric Halo's +DSP chip. The +DSP license unlocks dozens of useful plug-ins, the processing power of which, are handled in the unit with near zero latency. So, for example, if you wanted to throw a little reverb into a cue mix for a vocalist, you can do it with the LIO-8 before the audio even routes through your DAW.


Unique in the interface world in Metric Halo's MIO Console software. Unlike other DSP mixers, MIO Console does nothing for you in the way of routing other than create some templates to get started with. This is a good thing. Imagine buying a console and having the whole thing already wired up by someone else who didn't have your work flow in mind at all. Would you rather just work within some kind of pre-imagined framework, or would want to completely customize your work flow? Any professional user may find templates or presets useful places to begin or to experiment with, but by and large we want to customize, we want to dictate to the hardware how it should be routed, not be dictated to. In MIO Console you can basically route anything, anywhere and monitor it all before it travels through your DAW. This means extremely low latency.

MIO Console also gives you access to MH's Monitor Controller, which is a software based monitor controller. It is fully customizable and you can even calibrate different sets of output paths to particular monitor levels. Say you have one set of monitors that turning up to -12 is way loud but another set that it is too quiet. You can tweak the virtual output knob to calibrate to a level you set. This means the virtual output knob will behave as a coherent level adjuster across monitors sets without having to worry about jumps in levels.

This software even records! If you are one of those folks that would prefer just to turn on and hit record, you can basically use your computer as a hard drive to capture audio and let MIO Console and the record function do the rest. There is so much more to MIO Console that it would take up entirely too much virtual ink here so let's just say, you can pretty much do anything with it. Not to mention that in practical use, it is rock solid, that is, in my personal use, it has not crashed once.

In Use

There is a learning process to the way the hardware and software interact. As I mentioned, they really don't do anything for you. That said, if you have had your hands on a console and know your signal routing, it isn't difficult at all. I had output coming out of speakers mere minutes from turning the thing on and installing the software. The drivers and software are rock solid, no hiccups, no slow screen redraws, nothing. The hardware is very responsive to the software as well. The only thing more fun than creating your own personalized mixer and routing, would be to do the patching yourself on a real console (sorry, I kind of like patching things).

I only use the LIO-8 with Pro Tools 9 but again, there was no mystery here. I am used to new gear and especially a new interface, to kind of throw up ro*******s and confuse me and generally not work as expected at the beginning (and especially with PT 9). Other than hardware related issues (read below in "Customer Service") nothing got in my way using the LIO-8. I had more trouble with my Duet and getting Pro Tools to "see" it. Same goes for the Audio MIDI Setup as well. Even when my Duet was plugged into the power and connected via USB, it almost always needed to be reset for the OS to "see" it. Never an issue with the LIO-8... ever.

Patching this baby up is problematic for those who don't already have DB25 snakes, but really once you get over this aspect, it is actually quite nice to reduce cable clutter. Again, it is more fun to patch TRS snakes in my opinion, or at least not as satisfying but I tell you, when I look at the back of my rack it is nice to see it a little more clean and easier to navigate. Anyone need some cheap 8 X 8 TRS snakes? Ha! I am looking into getting an XLR patchbay once I purchase the ULN-4 part two to eventually get all 8 mic pres.

Honestly, I have some out board mic pres that I am primarily using at the moment so perhaps I will post a follow up to this gigantic review to comment more on that. Also, some hiccups as of late have made it difficult to do more testing at this time, read on...

Customer Service

It seemed that a better portion of the 90s and 2000s were racked with truly terrible tech support. It was almost as if companies were reeling with the complexity of computers interfacing with audio and it seemed almost Sisyphean to hope to get someone on the phone or return an email. One would typically get either an incredibly impersonal and indecipherable engineer who might be nice enough but could never explain to a regular Joe how to troubleshoot something. Or you would get a "God's-gift-to-IT" type who you could tell was getting some kind of bitter amusement to your problem, which to them probably had some obvious fix.

These facts have led me to do most of my own troubleshooting with computers and therefore, I actually know a lot more about the way my Apple computers work with interfaces than most. That said, my first LIO-8 unit did not arrive well. It had issues from the beginning and simply was not operating as it was supposed to. The issue I was having was so esoteric and completely unlike any they had experienced before that the amount of troubleshooting was quite exhaustive. I wont go into details because ultimately the issue has been settled but needless to say, it was not a common issue their engineers were aware of. We finally decided the unit was messed up and they replaced my unit with a new one within a week! Now, all of this might sound like, "well, duh, of course they are supposed to do that!" It isn't why they did it or even that they were supposed to, it was the way they encouraged me to troubleshoot and in such a way that I actually learned something about the way their product works. I felt as though I had a true technical partner in solving the issue.


One's expectations ought to be high for company that commands such a high premium for their products. Mine were and I was not disappointed. Metric Halo runs a truly remarkable business run by even more remarkable people.

13th March 2014

Metric Halo LIO-8 by elan

  • Sound Quality 5 out of 5
  • Ease of use 4 out of 5
  • Features 5 out of 5
  • Bang for buck 5 out of 5
  • Overall: 4.75
Metric Halo LIO-8


I bought this audio interface almost 2 years ago... I took some time to know it because the first impact was WOW exponentially, so I thought..."well.. give it some time, it will surely have something you'll hate"

People know I'm kind of picky, point is to me is really important to get back the value of the money I've spent.

Meaning, if I spend 1000$ I want to have back something that makes my life simpler as much as the money I spent

Well, that's a very expensive interface if someone looks exclusively at the price tag... and to me is REALLY FREAKING EXPENSIVE because I'm broke

Well, I also hated a bit seeing a lot of people pushing MH interfaces, like all the people who bought MH interfaces felt the need to tell how happy those interfaces made 'em

Well again... +1, me...

Never been so much happy and proud for something I bought, only things at the same level that came to mind are the MS20, and few other things

With the LIO-8 I got:

- 8 AD/DA channels of astonishing conversion
- 4 preamps with 90 freaking db of gain!!!! That sounds unbelievably good. You can put them side by side with hi end or even boutique preamps. Totally transparent and full of character... how do you explain this? A character that's not a color per se, but something like you say.. that's the MH sound... and it is totally clean and transparent... just everything is perfectly reproduced and you get an authentic feel even playing the guitar or anything else, through it
- 2 D.I. channels with adjustable gain that sounds amazing. I'm not using the Red Eye anymore... just if I need another channel. And the Red Eye alone costs 250 euros or more..ok it has reamp too, but the Radial JDI costs 200 and its only DI and the Red Eye DI is at the JDI level if not better...
- 1 world class headphone converter... never heard my headphones sounding that good, defined, harmonic, full! You hear things you've never heard in recordings you know since you were a baby
- Every channel is ground liftable... just move jumpers. If I'm not mistaken you can also use the outputs with headphones so you can connect up to 9 headphones if you need
- SMPTE... guys... you have a dedicated I/O for SMPTE!!!! No more wasting channel
- I got a mixer inside the LIO which is totally customizable and has its own CPU that takes care of everything, all compensated, hassle free. And there you understand what means parallel compression because in every DAW I tried it, it never sounded so great.. here you don't hear any phase artifacts mixing the dry and the compressed channel... explain me that. Some one has to tell this to Brauer because he doesn't use parallel compression ITB.. well.. he should try this. I can even use channel strip on my guitar, bass, voice, while I'm playing and eq it in real time... yeah you can do it with many thing but none of them sounds like a real EQ outboard does... I can use the mixer as a summing device and it does sum!
- I got a plug in channel strip that made me hate all the other plug ins I own.. so I sold them (losing a lot of money). I just hope to have the money one day to get a Channel Strip 3 native... because that's probably the only thing that can come close to the MIO Strip and isn't hardware.
The compressor in that thing makes you just understand how wrong the other plug in compressors are. Sounds so good, it never smashes the transient unless you deliberately ask it to do that and when it does it... well, it doesn't sound as a plug in...
Usually a plug in introduces certain artifacts, distortions, that sound really harsh.. even the supposed emulators sound harsh, grainy, everything but sweet, cohesive, real... every plug in sound fake in some way.. this... well, no. Even if you squash, I don't know 120db (it can do that, if you put the knee at -1), it sounds real, squashed but nowhere near harsh, hard, digital.. nothing like that.. I even heard some analog hardware sound harsher and even more "digital". Plus it is extremely creative. It can be totally wild or totally transparent even with a lot of db of GR.
The gate then is very fun to work with.. it is a gate where you don't have to find perfection, but performance. Make it swing and it will sound amazing in the mix (even though soloed could be a bit drastic sometimes) and even this can be extremely creative
The EQ... what an EQ... I've tried all the EQ on the market I think... I always go back to this... I prefer commit the audio then using other EQs... I'd love to be able to select -6 -18 -24 and maybe even an ultra steep slope... so sometimes I look for other EQ.. but in the end.. I always prefer the standard -12 slope of the MIO.... even though I'd like che MIO strip to go at -6 -18 or more, or at least just -6, so I can get -18 or -24 using two bands...
The point is I don't find a Q setting or a gain level or a frequency in which the EQ start sounding bad, strange, harsh, nasal, etc...

Oh.. another thing, I've measured the plug in, turning every setting to find it it does introduce aliasing or stuff... well.. no.. you can put it at extreme setting or whatever, it doesn't blink.... the only thing you can see is a full fish spine... of all the harmonics introduced.. and it is perfect, no artifacts, no aliasing, and also the harmonics are very loud compared to other plug ins.. like.. usually they are under -70db or even less.. here they are like -30/50db... as it is on certain HW outboard I own

I have a question: Is it a problem if I find myself using 24db in boost with that EQ? Because that happen quite often... and I feel guilty

- I also got a monitor controller... yes, is digital... so, on paper, you don't actually prevent your speakers..... since I got it my speaker have never been better... there's a way to calibrate the monitor controller... so you never exceed a certain level..... so in the end, add this to the flawless driver stability and I never got any problem of any kind

- I got a knob per channel to set the gain... so if something is too hot or if I want to push a preamp to hell.. I can turn down the line level... if something is too soft.. I can turn it up... not just -10+4 but pretty much everything, so I can use all my equipment better, with better gain staging and everything, leading to a better result

Another thing about the converters... they are true. No hifiness... no "I make it pretty so you like it more"... it is incredible how rich the recordings and the playback of other recordings, is. Comparing it to a smooth converter could almost sound "raw"... but comparing it to the original material sounds the same. The result of this is that if I put my bass on another converter and play it through the speakers... it sounds like a bass coming off an hi fi.. good.. but unnatural, strange, and you can feel it on your fingers... if I put it in the LIO.. it sounds like it is coming from an amp. Not meaning the LIO sounds like a bass amp... but the transient response is totally natural.. and you feel it on your fingers.. and you recognize your instrument as it is, as it sounds unplugged

Oh, you can also calibrate the converters level so you can actually work using k-system standards

Another very important thing, I got many audio interfaces and converters in my life... I've heard many others in studio etc.. I also got the 2882 and the ULN-2 for a short period... well.. the big difference you don't hear with other converters is, actually are:

1 - You understand what means 3D and what are reverbs and which are the good one and the bad ones. You hear the room. Usually you hear the shhhh or you hear the dimension in 2D... there you hear the depth. Certain recordings that had great space, dimensions, on other converters sounded more "in your face"... there you here the depth.. reverbs are less evident as an effect, you hear the room where the recording happened or as the FX was supposed to emulate it

2 - The sound is still. You don't hear any movements... you just hear the instruments moving, the sound moving, the original intended modulations... in other converters I always heard something was not consistent... with bad converters I felt almost seasick and these phase problems caused me a lot of hearing fatigue (now I know it, before I couldn't imagine a converter could cause more hear fatigue than another) now I can listen music for hours and never get tired.
It is a converter that doesn't try to impress you, lets the music impress you.

- Plus you have a very clever metering for every channel, an ASTONISHING reverb, the same as the MIO strip, it really doesn't feel like a plug in, you could put it against hardware and be impressed because you could even prefer it

Well... all that... and I'm surely missing something

With the LIO I feel everything is under control and I don't miss anything

Now, do all that buying all the stuff separated and see how much you spend... I consider this a Low End sound card on the price tag... even though I'm the first who would like it to cost half the price because I want more channels..... I'd love to have 24 channels!!!!!!

Oh.. and latency and stuff.. it is just something of the past.. I feel direct contact with the instrument in every conditions

Oh.. and also the thing "digital sounding" wouldn't be ended up in the AE dictionary if these were the audio interfaces, converters, plug in, on the market

And makes me think how many analog things I got or people get, to get a rid of the "digital sound"... while you just have to get a rid of your interface/converter/plugins... and use something like that

Thank you Metric Halo

I'd just would like to have more money so I can buy you more interfaces and plug ins and also support more your business

You got me a lot of things with that LIO, I almost feel guilty I cannot buy you other stuff
Obviously everything I said is my opinion, considering I'm a human being.
Honest communication is always unique and original. (Bob Olhsson)

I think the growing availability of presets in synths started to make musicians lazy: they were so amazed at what they could use, they stopped thinking if they should.

"Creativity is allowing yourself to make mistakes. Art is knowing which ones to keep"
--Scott Adams

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