Common computer music question - “Where do I plug in my guitar?” Turning your humble computer into a kick ass studio falls at the first hurdle if it doesn’t have something into which you can plug a jack cable. If you want to record live sound into your computer then you’ll need to consider getting hold of the right soundcard.

Most computers come with a soundcard of some sort. If your computer has speakers and makes bleeps and noises then you have a soundcard. The majority of soundcards are designed for games, multimedia and playing CD/DVD’s so not a lot of thought has gone into the ideal of serious studio recording. Nethertheless it is a place to start and we’ll come onto the proper gear in a minute.

Let’s look at the conventional soundcard. On the back of your computer you should find a row of coloured minijack sockets, these may be built into the motherboard next to the printer port or may be on a separate card in the slots to the right.

The picture above shows a Creative Labs Soundblaster Live card, a classic soundcard in the traditional sense. This is where the name “Sound Card” came from in that it’s a card that slots into a motherboard and provides the computer with a sound system. The sort of soundcards we’ll be talking about rarely come in this format these days but the name has remained. A colour coding convention of the soundcard inputs and outputs has developed which makes things a bit easier. Now I know the sockets are minijack’s but you could take your guitar lead, put on an adapter and plug into the pink microphone socket. A slightly better solution would be to come out of a preamp, or effects box and go stereo into the blue line input – this would give a reasonable input into the computer ready for recording. Would you expect the recording to sound any good? Well, if you think about it, you probably spent somewhere between £500 and £1000 on the computer, probably the same on your guitar, and yet your music making hopes and dreams all rest on a minijack socket on a soundcard that probably came included in your system for free. The built in soundcard is a starting point but it’s also a long way from where we want to be. We want something designed for the job, that has the right connections, studio quality sound and rugged enough to be used when drunk.

Taking the basic premise that we want to record a guitar and a microphone, at the same time, here’s a few good entry level examples.

Line6 Tone Port

There are two models, the UX1 and UX2 (pictured). The UX2 has 2 microphone inputs with phantom power, 2 guitar/bass inputs, stereo line inputs, mix and monitor outputs, headphones and cool assignable VU meters on the front.

You've even got footswitch jacks for start/stop control over software - pretty nice. It all comes with the Gearbox effects and modelling software taken from the Pod giving you a stack of great guitar tones. So you’ve got real inputs, real knobs and meters, and it looks nothing like you’d expect a bit of computer gear to look like. It comes with some simple recording software so you can get going and the Gearbox effects cover vocals, bass and guitar are genuinely really very good. Both units are capable of recording at 24bit and 48kHz. They connect to the PC via a USB (Universal Serial Bus) socket on the back on the computer which also provides the power. The UX2 retails for £149, the UX1 (1 microphone, 1 guitar input and no meters) for only £99.

Edirol UA-4FX

A silver box from Edirol that gives stereo or two mono channel recording at 24bit and up to 96kHz. You’ve got a single XLR phantom powered microphone socket and a Hi-Z input for guitar along with a high quality built in effects unit. 14 effects are available on inputs and outputs including COSM tube preamp modelling and multiband dynamics. It may not look as flash as the Tone Port but it makes up for it in connections having both optical S/PDIF in/out and a built in MIDI interface. The UA-4FX connects via USB from which it draws it’s power and comes with some useful recording software to get you started. Retails for £139. It’s as simple to use as it looks. 

Presonus Firebox

Another silver box, but much prettier this time, the Firebox from Presonus packs some serious connectivity into a little box. On the front you have a single microphone (with +48v) and a single guitar input, but on the back they’ve snuck in two more stereo inputs, one analogue and one digital S/PDIF, which are really handy if you have any external gear, like a sound module, keyboard or sampler that you’d like to record as well. Alternatively you could use two of the six outputs as an effects send to an external effects unit and route back in via the extra inputs. Quality is 24bit and up to 96kHz, connection this time via Firewire. The Firebox has a MIDI interface included and comes with some useful recording software to get you going. Retail is a bit more pricey at £199 which is because Presonus make some of the most professional analogue to digital converters in the business and that technology forms part of the Firebox which would give it a quality edge over similar devices.

Let’s make a leap to another recording scenario - the band. For this we’re going to need a number of microphone and instrument inputs as well as line inputs.

Presonus Firepod

A larger version of the Firebox, the Firepod sports 8 discrete mic preamps on the front, two which can be instrument inputs all in a tasty 1U rack box. The quality is fabulous with 24bit and up to 96kHz recording. You’ve got mix and monitor outputs, S/PDIF and MIDI. Could you really record a whole band with such a device? Lets have a look. Figure X, kindly provided by Presonus, shows a possible way of setting it all up. Not quite enough inputs for you then how about buying two and daisy chaining them together giving you 16 microphone inputs over Firewire. At around £500 it’s really not that expensive. 

A Quick Note on Computer connections

If a soundcard is not actually a card slotted into a motherboard then how do they connect to the computer? There are two ports used for connecting these sorts of external soundcard boxes; the Universal Serial Bus (USB) and IEEE1394 also known as Firewire. 

USB is most popular on PC’s as it’s an Intel technology and most computer peripherals such as printers, scanners, cameras, mice and so on connect via USB. Regular USB1.1 is quite a slow connection capable of moving stereo audio in and out of the computer. USB version 2, found on most modern PC’s, is much faster and can easily cope with shifting multi-track audio.

Firewire is an Apple technology which is also available on the PC but less common. You can add a Firewire card to your PC for about £10. The most common use of Firewire is with digital camcorders and external hard drives. Firewire is very fast and tends to be the choice for most multi-channel soundcards.

Another scenario – the Project Studio, where you want a bit of everything and you’re used to having and using external gear and are a bit unhappy about having to downsize to a mouse.

M Audio Project Mix

Yes it is a digital mixer but this one is designed for use with computer recording. Like the Firepod It connects via Firewire and has 8 microphone preamps, unlike the Firepod is has a control surface attached giving you tactile motorised fader control over your recording software. You’ve got rotary knobs, buttons, an LCD display telling you want each control is controlling, transport controls, scrub wheel, everything you need to control your software studio. If you need more inputs you’ve got 8 more channels over ADAT and S/PDIF digital. The Project Mix I/O also has the ability to run the M-Powered version of Digidesign’s Pro Tools software, the industry standard in studio recording software. Amazing and it’s just a soundcard, in fact you could use it for playing games through if you like. Priced at £949 it’s cheaper than most stand alone digital mixers but obviously not a casual purchase. 

You can climb further up the chain incorporating huge digital mixers or control surfaces. If you want to use an analogue mixer then that’s not problem just bus into the computer via a soundcard with 8, 16 or 24 line inputs – treat it in exactly the same way you would an open reel recorder. What soundcard should you get? The one that has the inputs and outputs on it that you need to connect to - there really is no mystery to it.

Sampling and the dispute over digital quality

Bits and sample rates get thrown around a lot when dealing with soundcards, this is because the soundcard is responsible for the quality or accuracy of the conversion of analogue signal into digital data. The incoming sound wave is “sampled” many times per second, set by the sample rate. Each sample is allocated a whole number from the available values determined by the bit rate. The more times a sample is taken and the more values available the better, or more accurate, the sampling will be. When Sony and Philips invented the CD back in the early ‘80s they decided that 16 bit and 44.1kHz was what was required to perfectly replicate sound – this has become known as “CD Quality”. 16 bits were decided upon because it was probably the best that current technology could manage at the time and it seemed to do the job. The sample rate was based upon the Nyquist theorm. Dr Nyquist (sounds like a Bond villain to me) stated that as sound is made up from sine waves, and any sine wave can be created mathematically from knowing two values on the curve, then any sound can be accurately sampled using a sample rate twice that of the sounds frequency. So a pitch of 10kHz would need a sample rate of 20kHz to sample it with 100% accuracy. Human hearing goes up to about 20kHz (on a good day) and so in order to reproduce everything we can hear with you would need a sample rate of 40kHz. 44.1kHz was chosen to add a little bit of ballast as science is never quite so perfect in reality. The problem is that many people feel that a sampling rate of 96kHz just “sounds better”. They claim that frequencies outside our hearing have an influence on the ones we can hear. In any case the DVD Audio standard has become 24bit at 96kHz to take advantage of the perceived quality gains. There is also a file size issue, in that DVD quality takes up three times the amount of space that CD Quality uses, 30MB per stereo minute compared to 10MB (roughly), and of course DVD Audio will be in six channel surround which is 90MB per minute, and that much more data means the computer is working much harder to process it. At the end of the day I don’t have a posh enough music system to hear the difference, however, I’ve found that working with 24bit audio files gives me a better quality 16bit file at mixdown than working with 16bit in the first place.

Drivers

If you needed another reason why you should think about investing in a more professional soundcard then I’d like to draw your attention to the drivers. A driver is a piece of software that provides communication between the computer and whatever device is plugged into it – in this case the soundcard. For regular games and multimedia cards the drivers are written to be very tolerant and good in any situation, this means that they have large buffers and built in delays to give the computer plenty of time to understand and process the data. These delays are known as “Latency” and you’re talking about anything from half a second upwards. In a game that’s nothing but when playing guitar that’s a lifetime. Soundcards designed for music have special drivers written for them that make them much faster, to the point where latency has ceased to be an issue. Anything under 10ms (milliseconds) is generally regarded as completely playable and to put some kind of perspective on it 3ms is like standing a yard away from your guitar amp.

There are four main driver types to be aware of:

ASIO – Audio System In Out, was developed by Steinberg, the creators of the popular Cubase music production software and has become the standard low latency driver for audio applications.

WDM – Windows Driver Model, is a much enhanced version of the Microsoft Multimedia Driver which can provide very low latencies with specific music applications like Cakewalk’s Sonar studio recording software.

WaveRT - The new audio driver protocol found in Windows Vista. Supposed to be a fabulous improvement on WDM - keep an eye out for this if you are running Vista.

GSIF – GigaSampler InterFace, is a specialised driver for running Tascam’s GigaStudio sampler software.

I hope you can see how central the soundcard is to your computer studio. It provides you with the physical inputs, it dictates the quality of your recording and it determines how well your system will perform. Make the right choice here, from as little as a hundred quid, and you’ll be a happy home recordist.