Firewire vs USB

[aquanaut]

Happy new year to everybody.

I don't have an audio interface yet and i'm looking at all those little unit under 500$. There's a big difference in price for usb unit vs firewire ones. Anybody know why. Audio quality? I don't have a big set-up here. I only need to plug 2 instruments. Also on a device like the Firebox from Presonus when you monitor with the headphone jack are you hearing what is going in the device or what's going out after it went thru the audio channel in logic.

Thanks

Nicholas

[mosc]

Spec wise the two are pretty much equal but there are arguments that firewire is a bit better even though it's specs are not quite as good. See for example: http://www.firewire-1394.com/firewire-vs-usb.htm You can find lots more info here http://www.google.com/search?hl=en&q=firewire+vs+usb&btnG=Google+Search

My take on it is go with Firewire unless you find a USB2 device you really like for price and features. Either interface will work well. Most new computers come with both interfaces, although USB is most prevalent.

[elektro80]

USB 2 is OK. I agree with Howard, but you should also be aware that the prices for firewire gear is falling. This is only natural, and there is absoluteley nothing that makes a USB2 interface noticably less expensive to make than a firewire interface. Firewire and USB2 interfaces should cost exactly the same.


Most vendors have kinda decided on firewire to have a better reputation and it is deemed mor "pro" than USB. That is why many are throwing a lot of more fetaures into firwire interfaces than their USB2 interfaces.
However, USB2 in itself is great and apart from protocol issues and port/bus issues than can be quite silly on certain budget PCs, audio interfaces using USB2 are absolutely OK. The problems you might experience are mostly about OTHER device drivers looing for passive/active gear on USB ports are behaving and NOT about how a well made USB2 interface works with well made drivers on a well configured PC.

Because firewire interfaces are now kinda "pro", some vendors are taking extra care to make the analog circuitry better and even though the digital secion of firewire /USB2 interfaces are pretty much the same, the analog section CAN be better on Firewire interfaces. Another issue is that you might want special features like adat lightpipe, spdif, word clock etc. so you should do some research on how you might want to use the interface if you get more gear later on.

If you are using a mac, get a firewire interface unless you really want a device with very few features at rockbottom prices. If you are using a PC and has a lot of USB paraphernalia attached already, go get a firewire PCI card and a firewire audio interface.

[vijayan]

Hiya !

Most of the firewire interfaces have a mixer knob that will allow you to set how much of the return signal from the computer you will hear in the monitors/headphones. Usually if you set it fully counterclockwise (atleast on the presous and edirol interfaces) you'll hear only the input signal and if you set it fully clockwise, you'll hear only the processed sound from the computer. You can adjust the knob to get a desired mix.

Make sure you are only looking at USB2 interfaces ! The USB 1.1 interfaces will definitely be much cheaper than firewire, but they have low bandwidth and usually high latency. (for only two inputs, USB1.1 might just work, but I'd still go for firewire). There is only one USB2 interface that is commonly available in the US, Edirol UA-1000, and it is quite expensive (~$800 or so). For under $500 fiewire, Presonus firebox/firepod is definitely a good option. The M-Audio 18/14 is also available for under $500 if you can find a good retail store in your area. I use the Edirol FA-101, and it is quite good, though lacking in software/hardware routing flexibility compared to the M-Audio's. The edirol A/ D/A converters are very very nice. Preamps wise, Presonus and M-Audio have good preamps (though i have found the M-Audio ones to be a little 'hot') The Edirol preamps suck (too quiet), but you can offset it by inceasing gain on your recording software. The noise floor is low enough that the edirol will end up sounding better than the other two.

Hope this helped

Swamy

[vijayan]

Just a quick addition : some of the recent firewire interfaces can be bus powered ! No external power needed to run the interface ! but they will work only if your computer has a 6 pin firewire connector. 4 pin firewire does not provide power. Interestingly, a 6 pin firewire hub (connected to a USB2 or firewire 4 pin port, which will unfortunately be the case if you have a dell laptop will not work either ! (unless you power the hub itself

[aquanaut]

[elektro80]

[aquanaut]

[elektro80]

Hmm.. what about the Edirol, the Motu or the RME?
That blurb sounds intentionally vague. Scary!!!!!!!
You are aware that the consensus over at recording.org is that the firepod is a child of Satan..? That said, it seems like if you don´t buy a pre or a compressor that costs at least 2000 USD you are one xxxx xxxx xxxx... so.. well.. perhaps this says more about that community than the actual quality of the gear..?

[mosc]

[elektro80]

The Presonus Firepod can hardly be bad, but in order to get your questions answered I guess you will have to ask a guy who actually owns one.

[elektro80]

[vijayan]

Yes, I have read on the web that the presonus interface specs are a little vague. I do believe one should be able to record on to 10 tracks simultaneously (8 preamps, stereo SPDIF) for 24 bit 48 KHz recording. Just make sure all channels are activated in the recording software (I have been playing with Nuendo, and you have to go to VST connections and add more input busses so you can access all the audio inputs) I have been able to record simultaneously from all my 8 analog inputs on the Edirol FA 101 (with very very low latency too, I must add). I haven't used the digital in yet.

Important : The number of inputs that will simultaneously record might depend on the sampling rate. You may not be able to record/playback from all inputs/outputs if you use 96 KHz or 192 KHz.

I think Presonus are good for their preamps, I don't know about the other components (converters, drivers etc) From what I have researched, all higher end interfaces (most firewire) are full duplex for lower definition recording. What they differ in is how much flexibility is offered in routing the inputs to the outputs and vice versa. I think the MOTU's are famous for this.. you can do hardware routing, software routing, external clock syncing etc.. RME are supposed to have very good DA AD converters.

Swamy

[elektro80]

The presonus preamps are OK, and the MOTU preamps are decent too.
RME is pretty much the same.

The only thing you should be aware of is that you might want some sort of compressor/lmiter on the analog channel inputs. I am not talking compression in order colour the signal or brickwall it or something.. but rather as tols for making the signal behave well. but this does of course depend a bit on what you are going to record.
Some slight comrpession/limiting is pretty much unproblematic. The whole idea is to smooth the peaks and prevent clipping. You can get great results without having such tools around, but then you simply must try to set the volumes right.

[mosc]

I agree about the the value of the limiting in the audio chain. If your levels are set right, the circuits won't kick in, but if your levels get really hot, you want to avoid clipping at almost all costs.

[elektro80]

I did a little trick years ago by recording a signal split in three components. I was doing some wild resonant filter synth stuff that would
down into continental drift territory and up up and away into hypersonics.
I set up one channel that managed the mid frequencies.. another for the deep and and the last for the highs. I used compresion and limiting seperately on each channel. with some trial and error I ended up with something that made sense ..on tape.. that is. I guess I migh still have DAT transfer of that piece.. so one day I migh try to reassemble that one and record missing parts if needed.

If you are going to record weird signals you will probably pretty fast experience the need to improvise various recording methods.

[jksuperstar]

I use an Echo Layla24. Can't say what the G3 version is like, especially the preamps. They are supposedly releasing a firewire version.

That said, the Echo products are extremely clean in the AD/DA department, and are very transparent to listen to. Inputs are very tolerant (+24db before distorting). The only drawback is that all products are PCI (or PCMCIA which I use with my laptop). This means you need a special adapter, no standard firewire to use them. However, the latency is basically 0, and the adapter does great noise shaping for converting various sample rates & bit widths.

The only reason I'd choose a MOTU over the Echo products is that the Echo can't operate stand-alone, and you can't use a MIDI controller to adjust levels of the Layla's mixer, which means you have to route through the PC, loosing the nice low-latency. Which sucks for live playback. It's not that bad though, I sync MIDI to match the audio delay.

Maybe someone knows of a MIDI -> windows script tool? Be nice to use midi to automate mouse clicks in a program that otherwise has no alternate user interface.


Also: I have heard that USB demands some level of processor intervention on a regular basis, whereas Firewire is more automated via DMAs (the host controller is a bit more advanced). I have no idea if this is true, but it would mean that a slower machine would not like to play with USB2.0 as much.

[mosc]

[tjt]

[zynthetix]

I don't know much about the harware spec differences between USB and FW, but I have been told that USB is fine for a couple audio channels going in/out. If you would be using more than that, I have heard FireWire is supposed to be better (more reliable? I don't know in what way though).

As for the # of tracks, that should be strictly limited to your DAW capacity. (Considering the under $500 units). You could have 80 tracks coming out of channel 1/2 of the audio interface, and a duplicate "mix" of this would be coming out of channel 3/4. Large audio interfaces (deluxe MOTUs) are a little different....it is designed so that each track in the DAW is synched with a specific channel on the audio interface...like track 1 of DAW comes out of Channel 1 of the audio box....This is so they can be routed into a mixer.

[mosc]

192 KHz * 24 bits = 4.6 Mbs (bit rate of one channel)
140 Mbs (approx speed of FW or USB2) / 4.6 Mbs = 30 channels

30 is the theoretical maximum number of channels at 192 Kbs and 24 bits (approximately). Experience with network is that they rarely exceed 60% efficiency at the application level, so a practical number of channels would be about 18.

Cut the sample rate to 96 KHz and you could expect lots more capacity. (36 tracks.)

Those are mono tracks BTW. Want stereo? divide the numbers by 2.

[tjt]

[elektro80]

True, and that pretty much indicates that Firewire has been accepted as the "standard". It also "helps" that Firewire is the de facto standard for videocam/computer integration.

[aquanaut]

Thanks for all the good advice on this immensely boring question. it helped pinpoint my search to 2 or 3 unit. i can't afford anything around 1000$.

Thanks again

n