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Hors sujet : Hakim, VH a dit "le son, c'est du bruit qui pense" bon la musique c'est aussi du bruit qui pense

Hors sujet : Tu me mets le gros doute pour VH car sur la toile effectivement tous les blogs parle de "musique". J'avais en fait un livre de proverbe où il y avait cette phrase où "son" remplaçait "musique".
Je vais faire des recherches approfondies et je te dis

Citation : "I went ahead and took a leap of faith and bought a MOTU 828mk3, with some reserve about being a public beta tester, but feeling brave nevertheless. The fellow at Guitar Center was happy to extend my return policy from 14 days to 30 days due to the possibility of dissatisfaction, which sealed the deal for me. I've spent some time playing with it and I feel qualified to do something of an in-depth review as a full time audio professional, so that prospective buyers can make a well informed buying decision. I am using it with a brand new iMac Intel 2.4GHz 24" computer and Logic Studio, Adam A7 monitors in a well treated room. I am using driver version 1.4.7 with firmware 1.05 and boot-loader 1.01.

All in all, the 828mk3 is a remarkable piece of engineering. There are a lot of features crammed into this one unit rack space device, and it takes quite a few hours of tinkering to understand how they all work. The new DDS clock gives the A/D and D/A conversion a serious upgrade from the previous generation of multiple I/O rackmount devices in this price range, and is comparable with the new JETpll clock on the converters of the M-Audio Profire 2626 and PreSonus Firestudio. These new advancements in converter clock technology finally make great A/D and D/A conversion a standard feature in the sub $1000 price range, which is cause for much rejoicing in the audio community. You will hardly believe your ears when you hear the difference on truly great quality monitors or headphones!

Finally, we can all afford to have converters with jitter less than 250 picoseconds peak-to-peak. This is still not real 20-bit performance with 120dB of dynamic range (that would require less than 25ps peak-to-peak!), but is very, very good sounding for digital audio nevertheless and worlds beyond any built-in computer audio output. The sound quality in terms of jitter is comparable with and in some ways better than the jitter present in the well-respected TC Electronic System 6000. The difference in sound quality between units like the 828 and the Apogee Ensemble or RME interfaces is now much, much smaller than it used to be, and for most people on anything of a budget will not be reason enough to shell out the extra $500-$1000. The main difference you see in that extra $500-$1000 is in the quality of the microphone preamplifiers, which does not matter for everyone, particularly those hooking up a few hardware synths to the inputs.

Using high quality headphones and monitors, the difference in clarity and stereo separation between the 828mk3 and my M-Audio Fast Track Pro is quite evident. Most of the outputs (with the exception of the dedicated headphone output, see below) have a noise floor too low for me to hear. The device in general sounds excellent, and while perhaps not quite as good as an Apogee Duet, Ensemble or dedicated rackmount converter, its the best you're going to get with this amount of I/O unless you shell out almost three times as much for an Apogee Ensemble, which has somewhat better-sounding converters, but even then you get a bit less I/O and no DSP. For $750 you get 12-built in inputs and 14 built-in outputs with the expansion capability for 16 more.

The built in DSP EQ, compression and limiting is quite good, finally making it possible to record at high gain levels without riding the gain knobs, and with no artifacts! The compression is much better sounding than your average rackmount analog compressor/limiter used for vocal tracking. The EQ is very transparent and musical, and the reverb is versatile and very useful for sweetening a monitor mix, though not nearly as good as a nice Lexicon or convolution reverb plugin like Logic's Space Designer. The LA-2A modeled leveling amplifier is good enough to use for mastering, which is a godsend, and sounds very close to the UAD card plugin emulation.

No device is perfect however. There are, as was to be expected, a few minor issues with this generally wonderful and high value device.

Outputs are definitely on the hot side, which has been noted by several users. They would no doubt blow out my speakers if I ran the device and my Adam A7 monitors on the "0dB" settings. I experienced output this hot on my Edirol FA-101 card, however, which leads me to think that perhaps this is less of a technical flaw than a simple engineering decision. There is something to be said for making a device of this dynamic range with as hot an output as possible. It maximizes the usability of the outputs for processing, mixing out of the box, and live sound, even if it requires over 30dB of total attenuation when used in the typical studio setting to get it down to safe hearing levels. After all, if a device is capable of over a 100dB of dynamic range with THD taken into account from jitter, it should be able to produce over a 100dB signal! To give you an idea of the output level, I was still getting quite audible sound out of my A7s playing a mastered song with their gain set to -60dB and the output of the MOTU set to 0dB. This makes sense, as the signal I was getting from the monitors was about 40dB. The dynamic range of many other sub $1000 sound cards is only about 80dB, so it makes sense they would be 20dB quieter at maximum volume. Even with fairly weak amplification, this device can produce levels that approach the threshold of pain, so be warned!

Despite the second port on most firewire audio cards and the extra firewire 800 ports on most new Macs, it is not usually a good idea to plug anything else into any other firewire port anywhere, whether via daisy-chain or another port on the computer. Unplugging my bus-powered firewire 800 drive altogether confirmed my suspicions, as the problems quickly vanished. It seems like the unit works fine as long as nothing else is plugged into any other firewire port, which may be of some concern to people with external firewire-only hard drives or other firewire cards. You will not be able to make use of any other firewire devices on your computer at the same time you are using this unit if you want to experience trouble-free operation.

Others have noted that it is impossible to separate the main headphone output volume from the main XLR output. This is true. However, listening to the mix and recording using two sets of headphones without having to turn off the monitors is still possible. Simply connect the monitors to the balanced TRS outputs 1-2, switch the main outs to the XLRs and the default outs to 1-2.

The only incurable annoyance is a high pitched, fairly quiet but definitely audible constant whining noise in the dedicated headphone output. This noise is not present in the (MAIN) headphone output. Checking other devices, I discovered quite a bit more noise coming from the built-in output of my iMac using the same pair of headphones, but no such noise at all coming from my M-Audio Fast Track Pro. I was not able to get rid of it, as the output makes the noise even when it is not connected to a computer. It seems completely unrelated to the level of the output and does not respond to changes in the setting. It is not noticeable when listening to music. I am not sure if others have experienced the same issue, but it is worth looking into. Perhaps it is a flaw with my particular unit, or perhaps it is inherent in the basic design of the output, I am not sure. One way or another I can always us the (MAIN) headphone output. I will try to find another unit and see if the noise is an isolated problem, and if so, will probably return it for an even exchange to see if I have better luck with the next one.

All in all, I am pleasantly surprised by the sheer volume of value in this unit. It is very expandable and seems fully capable of being at the heart of a professional studio.