Let's assume you have a fine PC now and want to add audio hardware.
Don't save money here! For good sounding recordings you'll need a good sounding audio card. And I don't mean a soundblaster here, because those simply don't sound good. Now comes the difficult part. Remember the questions #3 and #4 from part 1? How many ins & outs you would need? You should have an answer for this by now. For example, if you want to record a live drumkit, I'd recommend at least 8 physical inputs. Since the number of outputs is almost for all audio cards equal or greater than the number of inputs, decide the needed inputs first. There are cards available with 2, 4, 8 or even more inputs.
There are different kinds of audio cards. There are complete solutions that offer a number of analog ins and outs, which means that it has its own A/D and D/A converters. Most of them feature digital I/Os, too, which are a must IMHO. These things have the advantage that they're complete systems that usually work well right out of the box. Their disadvantage is that some are hard to upgrade, if you need, say, more ins.
Then there are digital-only audio cards. These have no converters, only a set of different digital interfaces, like SPDIF (most common stereo interface), AES/EBU (stereo), ADAT optical (8 channels per interface, common & recommended), or maybe TDIF (8 channels per interface, rare). The problem with those is you need external converters to hear something. The advantage is that a digital-only card is not as expensive as a complete solution. And they are easier to upgrade - you can start with an existing DAT recorder that you use as a stereo converter, and when you decide you need 8 ins or outs, buy another multichannel converter. And another if you need even more channels. But then you'd need a card like the RME Hammerfall, which offers a LOT of digital interfaces. Get in all cases a PCI card, I don't know if someone still makes ISA cards, but those are to be avoided due to speed issues.
How many bits do you need? The most common format for digital audio is the CD with a resolution of 16 bit and a sampling frequency of 44.1 kHz. Most "consumer" soundcards support this, too, and call this "CD-quality resolution". Now, the perceived sound quality is not alone determined by the number of bits per sample or the sampling frequency of the end product (the CD).
If you want to produce your own CDs (be it for your own listening, for a demo or for a full published CD), you'll end up with 16bit, 44.1 kHz. But how good this will sound depends on how good your recordings sounded in the first place. Now, lots of CDs were recorded on 16bit equipment and sound great. Nowadays, the standard for audio cards are 24bit converters. What benefit do these have? They offer a better resolution for lower level signals - those signals are represented by more bits, so they will have less quantizing errors and distortion. 24bit have a higher dynamic - on the paper at least. Theoretically, with 16 bit converters, you have a maximum dynamic of 96 db (this is the difference in volume between the loudest and quietest signal possible), while 24 bit converters reach 144db. You won't find a soundcard that has real 144db dynamics. The reason for this is the analog electronics that is located before of the AD-converters and after the DA-converters, like input amplifiers or output buffers. Every analog electronic component adds a bit of noise to the signal. This is unavoidable. This noise of the analog circuit limits the dynamics somewhat. If you buy a 24bit-soundcard that has 116-120db of dynamics, this is a very quiet device.
So 24 bit sound smoother with low levels, you don't have to worry that much about input levels (you can stay a bit below the maximum and still don't lose signal information), they capture more dynamics and more nuances, and are generally recommended. A good 20bit device would be running second.
How much kHz do you need? As I have said before, the standard for CDs is 44.1 kHz. This means that the maximum frequency that those systems can record is 1/2 of the sampling frequency, therefore 22.05 kHz. This is a good bit beyond what humans can hear. So why higher sampling frequencies? 48kHz (DAT standard) would allow recording 24kHz audio signals. 96kHz (proposed standard for the new DVD-audio) allows audio frequencies up to 48 kHZ to be recorded. Are we now making music for the bats or what? The answer has two parts. Part one is that having the higher sampling frequency, it is easier to have the signal processed ultra linear and without artifacts in the audible spectrum. Part 2 is that the human ear is not able to hear frequencies above 16-20 kHz, but it seems that it is able to resolve phase differences, that means for example differences in the arrival time of two audio signals, that are shorter than the period of a 22 kHz oscillation. There have been tests to show this. This means that those time difference/phase information cannot be recorded with 44.1 kHz. Now this information plays a part in creating spatial information in our brain, that means it enables us to locate sound sources precisely. That means in short, the stereo imaging of 96kHz recordings is perceived to be better. If you want to read more about high quality digital audio, check out: www.digido.com.
On the other hand, if your final product is a mp3-file with its bead stereo imaging anyway, this is moot. Or if you record mainly digital synths that mostly operate at sampling frequencies of 44.1 or 48 kHz.
Another thing: for better sound quality, the converters should not be located inside the PC. The inside of a PC is very noisy regarding electrical interference. So if the converters are in an external breakout box which is connected digitally with the PC card, you will get less noise and it's much easier to plug things into a box that is located in your rack on the table than having to crawl with a torch behind your PC :-)
Some cards even offer microphone preamps (like the Echo Mona), that could be a consideration if you don't plan on buying a mixer or external mic preamp. Regarding my experiences with Echo products (I own a Layla), I'd say those mic preamps won't sound half bad.
If you want to plug a guitar into your soundcard directly (that means even without any preamps, direct boxes or PODs), you will need a card that is able to live with the low input of a guitar signal. The guitar signal is in power somewhere between a microphone and a line level. Most line level inputs will have trouble with a guitar signal, causing high noise levels (because the guitar signal is too weak). If you want to do this (because you want to record ultra clean guitars or you want to add distortion in the software), look for a soundcard that says it has instrument-compatible inputs.
there are lots of others...
I can't go into reviewing lots of audio cards here since I don't own enough different ones and this would take too much space. So I won't give you a specific recommendation. Read the reviews, go for online forums like www.audioforums.com or the ones found at www.cubase.net to ask specific questions about a soundcard, someone who owns one will surely help you out!
Before you buy a card, make sure it will work with your PC. eMail the manufacturer the configuration of your PC (or what you want to buy) and ask them if the components you have work together with their card. Or search their website for a FAQ. I practiced this with Echo once, and if the manufacturer doesn't answer or don't have a FAQ, ask the online community about the manufacturer's reputiation and customer support quality.
And yet another thing: you should get a low latency card. Basically, latency is the time that the signal needs inside your computer to get processed and output again. Three factors determine latency: the processor speed, the cards driver/architecture and the host software. The problem with latency will be discussed in a later article. I give you only two key phrases: "low latency drivers" and "ASIO 2.0 drivers". Look out for those, discussion will follow later. Also, check if the card has drivers for the OS you want to work with. Win95/98 drivers are common, but if you want to work with Win NT or Win 2000, you have to look for a card with drivers for those...
Buy a 24 bit soundcard. Those are the standard nowadays, and having more bits is IMHO always better. Probably, this card will be able to work with 96 kHz. You have to decide for yourself if you need this, but all those cards can effortlessly work at 48 kHz or 44.1 khz as well. You should get one with an external breakout box, that has balanced connections if possible, and a digital I/O. Get a card for the PCI bus. Look for a brand card that gets good reviews in music magazines (be it paper or online). Don't save money on your audio card, save it elsewhere if you have to. With a good audio card you can achieve results that are in the same league as commercial CD productions. Notice that I have said "can", not "will".
If you want to do midi sequencing or if you generally want to work with midi gear (synthesizers, drum machines, samplers etc.), you'll need a midi interface. Most "consumer sound cards" like the soundblaster have one onboard already, so if you have one of those cards as a secondary soundcard (apart from your audio card), you can use its midi interface.
You'll need a midi interface for example if you want to plug your POD into your PC to deep-edit it's parameters with the POD-software-editor.
Some of the audio cards on the market come with a midi interface, too (like some of the Echo products).
How big a midi interface do you need? Midi interfaces come with different numbers of inputs and outputs, too. The soundcards usually have one in and one out. Now, for midi timing issues, it is always better if each midi device has its own input and output to and from the host PC. Midi is a slooow (31000 baud or so) serial port after all. So count your midi devices that you will use and you have the number of ins and outs needed for an *optimal* setup. Of course, you can chain devices together (via the midi thru ports), but this is regarded as sub-optimal, especially for multi-timbral devices (that's synths or samplers that are able to play more than one different sound at a time).
There are midi interfaces with one pair of ins and outs, 2 pairs, 4 pairs or even 8. Those come as internal cards (not recommended), serial port versions, parallel port versions and USB interfaces.
Parallel port interfaces *can* cause trouble when used on the same port as a printer, a zip drive or a dongle. Some Mark of the Unicorn (MOTU) interfaces are known to exhibit such bad behaviour. I'd say, USB is the future for this anyhow.
For more details on what midi is and how it works, see a later article (this is worth of an article of it's own).
Count your synths to determine the number of ports you will need. Nowadays I recommend USB midi interfaces (provided your PC has an USB port). The USB bus is fast, pretty much trouble-free (plug'n'play works!) and able to host a lot of devices plugged together to one port. Midiman (www.midiman.com) for example makes fine, affordable midi interfaces. Emagic (www.emagic.de) has good devices too, so do a lot of other manufacturers. As always, buy a brand name device with good driver support.
OK, that's it for the PC and directly related hardware. In part IIc I'll talk about other peripherals like monitors (for sound, not visuals), a mixer, microphones, outboard gear etc.
Stay tuned for:
Back to Part IIa
Part IIc: Chosing Hardware: other gear that you might need
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