MOTU 828 mk3 digital noise on Mac

[MikeMiller]

Hello, guys!

These days I bought my first brand new MOTU 828 mk3 and I was very dissapointed with the results.

I experienced the worst I could expect from this audio interface - a loud hiss or "white noise" coming from the inputs. I plug it to my Mac Mini with 10.7 Lion OS through FireWire cable.

So here's my problem described in several points:

1) The 1-2 front mic preamps produce a huge hiss even when nothing is connected to them and when unmuting them in cue mix and using a "trim" knob.

If trim is 0 db everything is OK! Then I start rotating trim knob right and increase the value and I start to hear a slight hiss even at +10db. When turning it more (+20, +30 or +40 and more) the hiss becomes incredible and the input gets useless for recording. So my first questions is what's wrong with the front inputs and why making a trim knob and +53db value if it starts hissing even at +10? How to record a high-quality signal when the input is hissing?

2) Rear analog inputs are even worse. The input level is very low. When "trim" in cue mix for analog 1-8 is set to 0db there's no hiss. BUT! This value doesn't provide the adequate recording level for outboard gear such as rack synths or samplers (AKAI, Yamaha etc.). I tried to plug my AKAI s1100 directly to the rear input. But actually the input level was very low. Ok, then I started rotating trim up to +20db and the signal from the sampler became louder but is was still not enough to fit in my record demands (Peak RMS at +24 trim can hardly reach -10 db level with the max (!) output set in the sampler). Also, it is insane to set up the max volume on sampler as AKAI recommends to set the volume at half.

In a few words: I plug any gear to the rear analog input - it is very quiet - i start to turn the knob at max on gear - it doesn't help - then I start to trim the input on MOTU from 0db to +24db to get a proper input recording level and I finally get the noise! Because the inputs trimmed at +24 in cuemix produce incredible hiss and noises! Is it a construction feature of MOTU 828 mk3? Why the inputs are so weak? In the manual (A typical 828mk3 setup) it is said that I can plug "synths, samplers, effect units" directly to rear analog inputs! In fact i probably have to use an external additional amplifier in chain to provide a proper recording level.

You might say that there's something wrong with my gear, but actually my previous cheap audio interface (Creative X-fi elite pro) which isn't even adapted for a professional studio usage has louder and cleaner analog inputs!! I may plug any gear to it, turn the input volume knob on a half and get a clean noiseless and loud input which is very good for recording!

And now the funny thing. I thought that the fault was in my outboard gear (synths, samplers). I even wanted to bring them to a service center but when I disconnected all the cables from MOTU 828 mk3 and still got that hiss and noise at the high trim values I was discouraged!

Please, give me an advice: should I get this MOTU back and buy another audio interface or there's another solution? Also explain me why the analog inputs on the cheap non-professional Creative X-Fi Elite Pro are less noisy than on MOTU? Or in other words, what should I do? This audio interface wasn't cheap but the way it works doesn't justify the money i've spent on it.

If some information or sound samples needed to identify the problem I'm ready to provide them.

Thanks!

[MikeMiller]

Guys! I'm sure there are many of you who uses MOTU 828 mk3. Is there nothing to comment on preamps and input quality and issues? I'm starting to thing that I'm the only one who have noticed this problem.

[monkey man]

Mike, I've been waiting on a unit for months; the wholesaler here in Aus typically doesn't hold much stock. It's only for my (first!) home stereo setup, to be hooked up to a lappie with Lion. I'll make a point of checking the line and mic inputs as soon as it's hooked up and get back to you.

Sorry to hear this. Hang in there. With any luck, all it'll require is a reset, driver update/ reinstallation or something...

[FutureLegends]

Hmmm... I've never noticed any of what you describe.
The gain in CueMix I generally avoid. This is not preamps. It's digital gain.

Sounds like you have a bad unit.

Or your gear is -10 sending to the 828's inputs which ae +4, I believe.

What are you connecting to the front mic pres?

[NazRat]

The only thing you haven't mentioned is your fader setting in CueMix FX. Do you have the faders up on the mix bus - 0db? OTT you're always going to get some hiss from any preamp when you push them hard. What you're describing may be a little excessive and you shouldn't have to push them that hard. I'd put in a call to Tech support - it may be defective. Noise on my unit is not an issue.

[bayswater]

When I got mine, it took a while to get all the gain levels in and out of the unit set up to a good balance between level and noise. I'd have to say the input levels showing up in DP were lower than I thought they'd be, but it's all clean and usable now.

Any chance you are monitoring the wrong outputs? I notice some applications output to Analog 1+2 even though I have the system set up to use Main Outs, and have my monitors connected to the Main Outs. When this happens, you can hear the output from Analog 1+2 bleed through to the Main Outs, but the sound is noisy and the output levels are low. You'd think that if the wrong outs are selected you'd hear nothing, but that does not seem to be the case with the 828.

[MikeMiller]

Guys, thanks for your replies!

I plug Yamaha TX802, AKAI s1100 and others. The fact is that I get a proper input level only from 2 front mic preamps. But I agree that "trim" is digital, so when you raise it you automatically raise the noise floor. Maybe it was made for live performance where noise is not so crucial. But for recording I have to leave it to 0.

Also I'm monitoring "Main Outs" so it's ok. There's no hiss itself. It only appears when unmuting inputs and trimming them.

As for rear inputs... well. To get the same input level as from the front mic preamps I have to trim rear at max. So the difference is about +24db.


I've made a test. I plugged AKAI s1100 to the front mic preamps and got -4.5db peak on bass drum. To get -4.5db peak from rear inputs I had to trim them up to +24db and add about +6db gain in DAW. Is it normal?

By the way! When trimming front mic preamps at +53db the noise floor is about -40db.

[bayswater]

I agree that "trim" is digital,

Not so. They are analog with digital controls.

http://www.motu.com/products/motuaudio/828mk3/i-o.html" onclick="window.open(this.href);return false;

In any case, as I said before, trim levels have to be higher than I expected, but yours seem extreme. Something's not right.

[MikeMiller]

If something was wrong I think there would be a problem with drivers or smth. Can anybody tell me, is there a different input signal level when plugging the same device in front or rear inputs?

I.e. you plug the guitar in the front preams and it sounds normal. Then you plug it in the rear input and it sounds quiet. Or you have the same input level from both front and rear inputs?

[NazRat]

Yes, the front are different from the rear. The front are mic/instrument level and the rear are line level. The front are designed for devices/instruments that have little or no output of their own and the rear are designed for devices with higher/hotter output levels of electronic gear, i.e. +4/-10 effects, outboard pre amps, etc. If you plug a guitar directly into the rear inputs the level will be much lower than the front. The way you would use the rear is to plug the guitar into an effects processor and then use the 'line level out' of the effects processor to the rear inputs of the 828.

[Parkol]

I have Motu 828mk3 hybrid and also hear a white noise when I add hardware synth in Logic Pro.

I have Nord Modular G2 engine and 4 outputs of Nord connected to 4 outputs of Motu 828mk3 hybrid and... when I add any software instrument, for example NI Pro 53 or smth., it sounds without any noise, perfect, also when I play Itunes and there's no any white noise. But when I add Nord Modular I hear that noise.

I've just bought this interface and it sounds amazing, but could you give me some detail advises how to stop that noise? Can I hear the clear sound of Nord Modular G2 in logic?

Thank you.

[masterlehand]

I had that too when i use the mics preamps of the 828 mk3, but not in the instr preamps. I changed drivers I changed firewire card and its the same. Pretty desapointing

[terrybritton]

Do you hear the hiss through the headphone jack while wearing good headphones?

I monitor both my Ultralite mk3 hybrid and 828 mk3 hybrid using Shure SE846 IEM's (which are very hiss sensitive) and never hear any hiss from any of my inputs that does not emanate from the source plugged into it.

Mics, of course, pick up the noise from moving molecules of air which our brains normally screen out, but in the isolated environment of the monitors, the brain does not screen it out in that case, so we hear it. I hope you are not hearing "air" in motion.

I also hope you do not have a defective unit!

Terry

[HCMarkus]

Sort of a necro thread here...

Unless one actually has a defective interface, excessive noise issues typically stem from poor gain staging or level mismatches. Consider these thoughts:

Make sure synth outputs are set to high levels when plugging into Line inputs;many synths allow one to set the instrument's overall gain. Go for +4 or higher, but watch out for distortion when playing lots of notes/parts on a multitimbral instrument.

Mic inputs at full gain will tend to be noisy. Use a good condenser mic, especially for low-level sources, to avoid using excessive gain on mic pre. (Yes, the MOTU mic pres may not be the quietest, but they function fine for most applications.) Larger diaphragm mics tend to be provide a more robust but less accurate signal than those with smaller diaphragms.

Always use balanced inputs and outputs when available.

Don't forget to gain stage your interface output>power amp/powered speaker input, too.

On a related note, make sure you record 24 bit files and leave ample headroom in DP. The take you save may be your own.

[mikehalloran]

When a synth is plugged into an input and you hear white noise, that's analog. If it's just one unit that does it, the 828 is not your culprit.

This is what everything did to some degre in the analog days. As has been suggested, carefull gain staging, shielding etc. are the keys to reducing it. Nothing makes it go away completely.

Little bits of noise are not an issue. Large amounts of it are. There are tools that can eliminate residual noise after the fact but it's much better to make as much go away as possible before hitting Record.