admin: First posted on 2006 09 11
The good soundcard is also a must for home recording. Standard soundcards that come with contemporary computers are not great. They do not have a good frequency response. They are not shielded. They do not have the necessary inputs. Unless you are recording only simple demos you should look for a better soundcard. There are many good soundcards and they all have various characteristics. Some characteristics are easy to explain and some are more complex. I will list some of the obvious ones: number and type of inputs, mixing consoles, and so on. I will skip esoteric ones such as signal-to-noise (S/N) ratio and analog-to-digital (A/D) conversion accuracy, as those will not help you in choosing the best sound – it is difficult to understand how those affect sound quality anyway.
Choosing a soundcard should depend on your particular situation. I rarely record more than one track at a time (which creates problems with song dynamics, but anyway). Hence, I do not need many inputs for most sessions. I do want additional inputs for the drums, but luckily my drummer has a mixing board and so I still record only one (stereo) signal. I usually carry a PC from a place to a place, so I want portability. Since I do not care about many inputs and I want to move around, I would probably want a small external USB breakout box. Your situation may be completely different.
Below are some of the simple characteristics of soundcards. First, here are the two main types (at least at the time of this article): an internal card (e.g., one that works on a PCI slot) or an external breakout box (e.g., USB or FireWire). This is a bit confusing, as there are PCI cards that extend into breakout boxes with inputs and outputs. For all practical purposes those are PCI soundcard. I personally like USB boxes, because it is easy to move them from a laptop to a laptop, but PCI cards can draw more power and are faster, which means that they can provide more connections and processing power (at this point, for example, there are no USB cards with more than 4 inputs). PCI cards have also been around longer and offer more variety. FireWire is also faster than USB, but there are not too many PCs with FireWire. If you are а Mac user then you may just want to use FireWire, but judging from the latest commercial magazines (as of early September 2006), the USB format appears to be the most popular one on the market.
Now here are some useful questions about soundcards, starting with - is the soundcard a full duplex? This is almost a useful question. Most contemporary cards are full duplex. A soundcard is full duplex it is if it can perform simultaneous recording and playback. If you are working with a card that is not full duplex, you can record your guitar along with pre-recorded drums, but when you play back the result the two may not come in at the same time, making recording all but useless.
How many analog inputs do I need? Drummers could go crazy on that one with a kick, snare, and hi-hat mike, alongside potential mikes on the ride, toms, overheads for the cymbals, and yet still other arrangements. Be wary of the advertised inputs and outputs. The soundcard inputs and outputs in most cases are not what they seem. A soundcard that advertises two inputs may really have only one, but with a left and a right channel. This is OK for two guitars, but takes only one stereo output of a mixing board. Watch out also for the number of 1/4” and XLR inputs. A soundcard with two 1/4” and one XLR input may in practice have only one input. The two 1/4” inputs are just the two channels of the same input and the XLR may override the 1/4”, so that you can only use one or the other, but not both. Sometimes the design is such that the XLR and 1/4” are combined so you can really only plug in one component at a time.
What type of analog inputs do I want? In general, you will have 1/4” TRS or TS and XLR inputs, which can be balanced or unbalanced (usually at -10dBv balanced or +4dBu balanced). A balanced signal sort of requires three cables or pins, so TS is usually unbalanced. The TS has only two pins one of which carries the signal and the other one carries the shield or ground. The XLR and TRS inputs can be balanced, which means that two pins/cables carry the signal (out of phase) and the third is the ground or shield. In some designs soundcards may have an XLR input but the internal circuitry makes this balanced input function exactly like unbalanced, but this is impossible to tell from looking at the soundcard. Balanced cables and connectors carry a stronger signal (carry the signal twice) and are usually preferred. True balanced designs are more expensive as they require more circuitry/hardware to implement. But check what you will plug in there. You can get a balanced output from a guitar amplifier, but you cannot get one from your guitar.
I can describe soundcard inputs and outputs forever. There are many types and standards, but the point is to concentrate on the simple stuff that is most common across soundcards.
Do I want a headphone output jack? The answer must be a "yes" for a couple of reasons. First, mixing the same song repeatedly over the monitor speakers in the wee hours of the morning can get annoying quickly. Second, it is cheaper to buy good headphones than to buy good monitor speakers. For my best mixes I used $140 Grado headphones. I could have spent over $1,000 getting monitor speakers that provide the same quality, and those would not have worked well in a small apartment. We recently went through a long process of mixing a song over my monitor speakers only to discover that the left-right balance turned out wrong. One of the speakers was too close to the wall. The rule-of-thumb ratio for cost-to-benefit for headphones to speakers is eight to one - headphones should cost 8 times less than a comparable loudspeaker.
What is the quality of the headphone out? That is a difficult question and is not anything I can help with. I can only say that I have so far been happy with the quality coming out of the Aardvarks and not happy with the MBox. Isosceles (one of our bloggers) on the other hand is of the opinion that most headphone outs are bad: "This again is a function of cost. Most headphones outputs are cheap "add-ons" to the design and are not properly thought out circuit designs with the associated higher costs (check out www.headroom.com)."
How many analog outputs and what type? That is another difficult question. As with inputs the types of outputs vary. Speaker outs help. As much as I like mixing on headphones it is sometimes good when more than one person can hear the mix at the same time. Also, from a practical or historical standpoint most people will listen to your music through loudspeakers and so you may want to target the mix for those. The advent of personal music devices reduces this concern, but you should have at least one left-right pair of analog outputs. What I always found interesting are cards that have more outputs than inputs. I guess that makes sense if you want monitors for the engineer, the drummer in a separate room, and the rest of the band, but that is not useful for my apartment.
So far we covered analog inputs and outputs. MIDI (Musical Instrument Digital Interface) inputs and outputs are nice if you have MIDI equipment (e.g., a keyboard) and MIDI editing software. You could record the keyboard output to a MIDI file and edit it later. We have not done this yet, but then we did not have MIDI editing software until recently. Other than MIDI inputs and outputs, you could have a variety of other outputs for who knows what reason. I am guessing that one reason is that companies cannot agree on a common format and push proprietary designs.
Is my soundcard shielded? It would be good if it is shielded to reduce noise from unwanted interference. All electrical devices in your apartment emit interference, including televisions, refrigerators, lamps, etc. I went through two Aardvarks, one nice and expensive for that time, and one small and cheap. The first one used a shielded breakout box and connecting cable. The other one connects through a USB but the unshielded breakout box picks up noise. I will sometimes move it away from a desktop monitor or turn the monitor off to prevent noise.
What does the soundcard mixing console look like? Soundcards come with a mixing console, which can be a software console similar to a computer software application that allows you to control levels and other things, or it can be a bunch of knobs on your breakout box. I find knobs easier to deal with for level control, but software could be easier for a patch bay. The mixing console is important. Only after looking at the console on one soundcard I learned that it was a "true" mixing board with compression, reverb, auxiliary channels and so on. Then I decided I would not like two large control consoles for my recording – one on the soundcard and one on the recording software. It requires too much attention. So I sold the nice mixing console soundcard and bought a cheap one with one knob (for the input) and one lever (for the output).
Does the soundcard come with any recording software? My first Aardvark came with Samplitude. My friend’s Darla came with a limited version of CoolEdit Pro. My other friend’s MBox came with ProTools. My Lexicon came with the Lexicon reverbs, which people like. Software is a nice addition, but you have to be careful whether the soundcard can use only this software (e.g., MBox) or other software as well.
There are other software issues. If you buy a complex piece of equipment you are bound to have issues with its software. I had issues with the Windows XP drivers for my Aardvark DirectPro, my friend had issues with his MAudio until the company updated the drivers, the Lexicon drivers seem to work well, but I was not paying attention and installed it on Windows 2000 (it works only on XP) and ended up almost destroying my machine (in retrospect the installation should have stopped me, but you can never make software idiot-proof). About the only card I have not had problems with is the Aardvark DirectMix USB 3, because it does not require drivers. It is a simple USB sound device and that is all. About the only advice I can give here is – buy from a company that has a proven track record. If it continues to exist it can at least update its drivers.
What about supported sampling rates and bit resolution? Soundcards will support a variety of sampling rates (22 kHz, 44.1 kHz, etc.) and a variety of bit rates (8-bit, 16-bit, etc.). I am guessing they would all support a CD-quality sound, which is 44.1 kHz 16-bit sound, but you may want more. At some point I should write a post describing what all this means, as there is actually a lot more to sampling rates and bit resolutions, but for now I will repeat what I said in a previous post: We do not produce our sound much and we mix and master for a CD, so I am happy with the CD-quality sound. Most listeners do not have the equipment to reproduce a 24/96 sound and will basically listen to a 16-bit, 44.1 kHz CD. It is also not clear whether the human ear can actually pick up the 24/96 quality. This means that the 24/96 quality may only be useful during the mixing and mastering stages.
Do you need phantom power? Some microphones require additional power to work. Our Rode NT does, and most large condenser mikes seem to require phantom power. If we were to plug it straight into a soundcard that does not supply phantom power, it will not work. Other mikes do not need phantom power and some mikes, especially older ones, may be damaged if it is supplied to them. Also if you have a separate mike preamp with phantom power, then the phantom power of the soundcard is useless.
Latencies, buffers? A good question would be whether you can control buffer sizes. I would not even know how to properly describe this without much more space. In short, larger buffers mean slower response times but provide more real-time processing power.
And finally there is the question of sound quality. Hopefully somebody you know is using the soundcard you are about to buy, and so you can check it out. Or hopefully the store has a return policy. You could check is the card’s frequency response, signal to noise ratio, analog to digital and vice versa conversion accuracy, timing accuracy of digital samples, accuracy of through circuit, and related concerns. Sometimes these would be printed or published on the internet. Those are useful criteria to compare across soundcards, but for the most part you never really know what they mean. I can see frequency responses published as a range and I know that within this range the response is probably not flat, but I do not know how many decibels it deviates here and there and I do not really know how much deviation is acceptable or the industry standard. Not to mention that the frequency response is probably measured with a clean sine wave sweep and chances are your soundcard will never record a clean sine wave sound. Advertisers got savvy in the 1970s and produced/created a number of confusing and mostly useless statistics (total harmonic distortion, being the classic example). But you can at least compare across soundcards.
So what do we use? Here are some of the cards that we use or have used:
Aardvark DirectMix USB 3 – USB. One 1/4” mike input, one 1/4” headphone out, one line input (two 1/4” channels - left and right), one line output (1/4” left and right). No XLR inputs or outputs. I bought this for $200 two-three years ago and I think they run for $100 now. Plus nowadays there are a lot more and probably cheaper USB cards. The best thing about it is that it does not require drivers and basically works on any computer. Two knobs for the input levels - one for the mike in and one for the line in. One output level lever controlling the output and the headphone out. No software mixing consoles. No 24-bit resolution or 96 kHz sampling rate support. No phantom power.
MBox – USB. 1/8” headphone out, 1/4” headphone out. Two 1/4” inputs. Two XLR inputs. One two channel output. Comes with ProTools LE for about $350 for both Mac and Windows. Works well. The ProTools LE mixing screens are basically the soundcards mixing console, but there are also buttons on the card itself.
MAudio MobilePre - USB. One (two channel) 1/4” output. Strange inputs: Two 1/4” TRS input, two XLR inputs, one 1/8” TRS input. 1/8” headphone out. Knob controls, one of which is a separate headphone out, and a simple software mixing console with gain controls. Phantom power. No 24-bit or 96 kHz support that I can find. No MIDI inputs or outputs. It runs for a little over $100.
We used the Aardvark DirectPro 24/96 - good internal PCI card with a shielded breakout box. 4 XLR and 4 TRS 1/4” inputs (but it is one or the other), 3 1/4” two channel outputs, 1/4” headphone out, internal reverb, compression, and equalizer. I bought that one for $600 years ago and sold it recently for about $300. MIDI in and out. 24-bit and 96 kHz support. Phantom power. Nice mixing console but with a confusing patch bay.
We also used Echo's Darla - smaller, internal PCI with a breakout box, now definitely dated, but Echo have made other good soundcards (Gina, Layla, etc.). Good soundcard since we never had glitches using it. If I remember correctly it had one or two two-channel 1/4” inputs and one or two two-channel 1/4” outputs, plus a 1/4” headphone out. Simple software mixing console.