If I want to use a pair of A3X and a sub, I just need to buy Focusrite Scarlett 2i4 and connect the speakers and sub to it and to my computer, is that right?
That's correct KC but I'm glad of your question. It allows me to expand on what I have previously written and hopefully help others. In the last few weeks I have answered several queries from HF members uncertain how to best integrate active monitors and subs into their existing systems. I could have done the same with many more.
In recent years many audiophiles have begun to see great benefits in using active desktop loudspeaker systems similar to those used by audio professionals for decades. It's been a noticeable trend in an otherwise moribund market. Some of these smart buyers have not yet fully realised that such monitors were originally designed to be used with a mixer. Which these days almost always means a pro grade multichannel audio interface. Individually active monitors and audio interfaces are great but combined they are brilliant. Like Strawberries and Cream or Fish and Chips. Made for one another. In heaven.
Partly this is because you can control gain on all inputs and outputs, inc headphones, with a handy physical knob. Partly it's because you can use balanced inputs and outputs thus gaining 6dB and guaranteed immunity to interference and ground loops. Partly it's down to the quality and range of the included mixing, routing, EQ and effects suites. Software is a major part of most pro audio suppliers business so they employ skilled programmers as a matter of course.
Mostly though it's due to the incredible flexibility and expandability. The audio interface becomes the control centre of your entire audio system. Weaving all your diverse components into one cohesive whole. It connects anything and verything together. Seamlessly and with total user control at all times.
I'll try to explain using the example of a MOTU Ultralite. It's a unit I know well. There are many excellent alternatives. 500 Euros in EU or 550 Dollars in US.
http://www.motu.com/products/motuaudio/ultralite-mk3
It will I/O to digital via USB 2.0, Firewire or S/PDIF. 8 analogue inputs including 2 microphone preamps and Hi Z instrument jacks. All balanced if required. 10 analogue outputs. All balanced if required. Plus headphone out. 14 bus (7 stereo) mixer with trim, 7 band parametric EQ, Reverb and 2 compressors available on all inputs, outputs and mixes.
Now you might say 'Ron that's fantastic but I don't need 10 ins and 14 outs'. Except you do. You just haven't realised yet.
It changes all the time but right now I've got the following inputs more or less permanently connected. Turntables and mixer, for vinyl. Receiver, mainly for radio. A HD Bluetooth receiver, mainly for guest 'phones and laptops. A desktop condenser microphone, for talking. Guitar pickup. Return from recorder. Output Mains to desktop speakers/sub, 1-2 > Amp for Big Speakers used for parties, 3-4 into the kitchen, S/PDIF/7-8 to recorder. One stereo pair going spare atm. 8 analogue outs is a good number because you could drive a 7.1 system. I don't have a MIDI instrument but a control surface would be cool at some point. Headphones can monitor any or all channels. Useful for cueing.
All this can operate at the same time. Radio to the kitchen, Music on the speakers, Speech on the mic. Cueing on headphones. Record TV, Backup data. Record anything with the push of a button. An incredibly versatile switching system. All controlled by front panel knobs if need be. It's even portable.
Audio quality? Clean and transparent. Pristine. When I first got it I was surprised to find I couldn't distinguish between direct and A/D > D/A routed signals. So I looped the output back to an input 4 times. D > A > D > A > D > A > D > A. Still couldn't tell which was which. Nether could anyone else I tested it on. Someone posted an example on the Internet of a file looped 30x and asked people to ABX them. No one could afaik.
So that's why I would recommend active multimedia monitors and an interface rather than direct USB atm. It will not cost you much, if any, more money and it's far, far more versatile. You might not think you need multichannel audio right now but once you have access to it you will soon wonder how you ever managed without.
ed spl
If you get stuck there are always people here to help.
