Choosing & Installing PC Soundcards

If you're considering buying a new soundcard, you ought to check its compatibility with your motherboard chipset first. Visit the motherboard manufacturer's web site to found out which one your PC uses.

Martin Walker offers some practical advice on choosing soundcards that will work in modern PCs without falling foul of chipset or driver compatibility problems.

Way back in SOS February 1999 I wrote a PC Musician feature explaining how to install and run multiple soundcards in a single PC to add more audio channels, built‑in sampling or MIDI synths to your sonic arsenal. It also covered driver restrictions, starting and stopping them in unison, and how to lock multiple cards together to keep them in perfect audio sync. However, a lot of water has passed under the bridge since then, and the range of soundcards available has changed almost beyond recognition, with even entry‑level soundcards now offering 24‑bit/96kHz capability, so the time is ripe for another look at these issues.

Sadly, the biggest new problem area to discuss this time round is fairly fundamental: the fact that some soundcards refuse to work in certain PCs. So, let's get straight down to a discussion of one of the most frustrating, annoying, and confusing aspects of buying a new soundcard.

Chipset Incompatibility

Musicians would have a far easier time if only all soundcard manufacturers would provide simple, clear, details of any known incompatibility, as Soundscape do here for their Mixtreme card.

There have always been some soundcards that have been fussy about what else you had in the computer. However, over the last couple of years a huge number of musicians have run into compatibility problems relating to one specific area — AMD processors. Now before a lynch mob of Athlon evangelists descends on me, let me reassure you that I'm not saying anything against AMD processors per se, or that they are the direct cause of soundcard problems. In fact these problems are nearly always due to incompatibilities between the soundcard and the motherboard chipset. It's just unfortunate that the majority of soundcard incompatibilities relate to motherboards with AMD processors, since Athlon floating‑point performance — which is very important for audio plug‑ins in particular — is now generally acknowledged to be excellent.

Every soundcard manufacturer will, of necessity, test that their products are fully compatible with PCs containing an Intel Pentium or Celeron processor and an Intel‑designed motherboard chipset — this is still the most common configuration worldwide, and thus the lowest common denominator. However, a much bigger range of chipsets is available for AMD‑based motherboards, which makes it far more difficult for soundcard manufacturers to provide cast‑iron guarantees of compatibility across the board with Athlon/Duron systems. Many current soundcard designs were also on the drawing board long before the Athlon appeared, so you simply can't expect them to have taken it into account. There are also a few third‑party chipsets from such companies as Via for motherboards featuring Intel processors, and these have had teething troubles too.

Some soundcard manufacturers do test both new and existing models with at least one AMD‑based chipset, but others stick to recommending Intel products only, meaning that Athlon owners may get little or no technical support if they do get problems. With at least eight chipsets currently available for the Athlon, and new ones being launched every few months, it would be almost impossible for many manufacturers to keep up with all the options — but while researching this feature I was surprised at how many still don't mention anything about AMD on their web sites at all. Even if information is provided, you may also have to ferret about a bit: when I did find information it was variously in FAQs, Tech Support, on a separate Compatibility page (possibly the best approach), and in driver release notes for specific soundcards.

Consequently, many Athlon/Duron‑owning musicians buy soundcards blind, either because they don't know a possible problem even exists, or because they can't get a definite answer from the soundcard manufacturer. The only answer in many cases is to ask other musicians who've already taken the plunge, so this is quite a common request on the SOS forum.

Athlon Motherboard Chipsets

Sharing interrupts between expansion cards can be a great help in a well‑stuffed PC, as shown here, but it will only work when all the devices using a particular interrupt support sharing.

The first step in anticipating possible compatibility problems is to find out which chipset your PC uses. To do this, open Control Panel and then System, and look in its Device Manager; under the System Devices section you will find the names of each chip of the chipset. Alternatively you can open up your PC and look on the chips themselves for a manufacturer's name and part number. However, both of these methods can be confusing, since there are normally two or three chips in a specific set, each with different numbers, so probably the easiest way is to look in your motherboard manual if you have one, or determine the make and model of your motherboard and then find the information on the manufacturer's web site.

So which chipsets cause the problems, and what can you expect? Well, one of the most common incompatibilities is between the early AMD 750 chipset for Athlon processors, and the Motorola DSP chip used on soundcards like Soundscape's Mixtreme, the Echo range, and the Lexicon Core 2. Aardvark soundcards won't work with this chipset either, so I suspect they also use Motorola DSP chips. Some musicians suffered loads of clicks and pops, while others couldn't boot up their PCs at all once the soundcard had been installed. There is no cure, but only early Athlon motherboards used this chipset, and in general AMD's more recent AMD 760 range has been declared compatible with all these soundcards.

Via have quite a few different chipsets available, including the Apollo KX133, KT133, KT133A, and KT266 for Socket A/Slot A motherboards used with Athlon/Duron processors. The KX133 appeared shortly after AMD's first 750 chipset, and also proved problematic, although Soundscape have publicly declared it compatible with their Mixtreme card, and Aardvark with their range. During my researches I came across reports of M Audio cards getting stuck in infinite loops during playback with AMD‑Via combinations, particularly when playing Windows sounds — this can apparently be resolved by running a small patch file. MOTU also report that they have been able to get some more recent Via chipsets to work with their soundcards after downloading the 'four in one update' from www.via.com.tw, while Echo have reported that their cards have problems with IRQ routing in Windows 98 with Via chipsets, although many of their customers have solved these by downloading the 'IRQ routing miniport driver' from the Via web site.

If you want to 'go Athlon' then buying a motherboard using the Via KT133A chipset (an update of the earlier KT133) is thought to be the safest bet for musicians, but it's also important to buy a well‑known motherboard make and model — cutting corners to save a few pounds off the price can backfire on you. However, a new scare appeared in April 2001, when it was discovered that various Via chipsets caused audio crackling during large file transfers between two hard drives connected to different IDE channels. Soundblaster Live! owners seem to have been particularly affected, and the crackling was apparently caused by a problem with the Via 686B Southbridge controller chip. Unfortunately this chip is not only used with Via's own KT133 and KT133A chipsets, but may also be used with other chipsets including the Apollo Pro 133, KX133A, and AMD 76x chipsets too.

There have been a few temporary BIOS fixes for this involving adjusting various PCI settings, and you can download a third‑party patch that performs these adjustments automatically (see Further Reading box). However, as I finished this column Via announced that they will be posting a new IDE driver for users of the Soundblaster Live!, and that they haven't found any other configuration that suffers from the same problem. Mind you, users of other consumer soundcards have also reported the same symptoms, so the problem doesn't seem to have been completely solved as yet.

If your Athlon motherboard uses chipsets from other, less well‑known manufacturers like ALi and SiS then you're even less likely to get a definitive answer from a soundcard manufacturer. That's not to say that you'll get problems, just that few people will know the answer. SiS have recently released a new 735 chipset for Athlon/Duron motherboards which seems to be outperforming AMD's 760 and VIA's Apollo KT266 and KT133A, but it's just not been out long enough for many real‑world soundcard tests to have taken place.

Those with older PCs don't escape either — a few manufacturers have also posted details on Socket 7 chipsets supporting the original Pentium and AMD K6/K7 processors. MOTU state that older SiS and Via MVP3 Socket 7 chipsets are incompatible with their PCI 324 card, and Yamaha have also pronounced some older sets such as the SiS 5596/5598 and Opti Viper incompatible with their SW1000XG, but I doubt that this will worry many musicians nowadays unless they are intending to buy a new soundcard and install it in a PC more than three or four years old.

Intel Motherboard Chipsets

It's essential to check that your motherboard chipset is compatible when buying a soundcard, particularly if you're using an AMD processor.

If you have an Intel Pentium II or III processor, or an Intel Celeron, then fewer chipset options are available. Most musicians are still likely to have motherboards either featuring the older but very reliable Intel 440BX chipset introduced in 1998, or the newer Via Apollo Pro series for Socket 370 and Slot 1 motherboards, which includes the Apollo Pro 133, 133A, and 266. These had clear advantages over the older 440BX in some areas of specification (see 'Solid Foundations' in SOS January 2000 for further details), but in practice the Intel 440BX held its own in performance terms, and is far more likely to be compatible with every soundcard. In my researches I came across a few users claiming compatibility problems between Echo Layla and Gina 24 models and the Apollo Pro 133A chipset, but nothing concrete.

Intel next introduced their i820 chipset, but this could only use expensive RDRAM memory, never really took off, and did apparently suffer some compatibility problems. Far more successful have been Intel's i815E and i815EP (a version without the built‑in video support) chipsets for Pentium III and Celeron processors, as used in the Asus CUSL2C motherboard and much praised by musicians. A reliable source who installs different soundcards in PCs on a daily basis told me that the only problems he had found with this were with Lexicon's Core 2 and the Turtle Beach Montego II, so it still pays to be careful, but that the vast majority of soundcards are very happy with this chipset.

This largely brings us up to date with Intel's fairly new 850 chipset, as used by the latest Pentium 4 processor range. Once again this uses RDRAM and is still fairly expensive, but supports the fastest currently available processors — up to 1.7GHz. I've no doubt that a few soundcard incompatibilities may exist, once again because nearly all current soundcards were designed before the Pentium 4 range was released. However, you can bet your bottom dollar that all new soundcards will be tested with the 850 as a matter of course.

Cards Not Recognised

Although most music software lets you address multiple MIDI ports, choosing Microsoft's MIDI Mapper as an output lets you send each MIDI channel to a different port, even with applications that can only select a single MIDI output device.

Having dealt with chipset incompatibilities, let's turn our attention to other soundcard installation problems. Occasionally you may find that your new soundcard hasn't been recognised, and you don't get a 'New Hardware Found' message when you reboot. The chances are, in this case, that your new soundcard simply hasn't been pushed home properly in its slot. However, I have also had this happen in isolated cases where Windows gets confused with an existing soundcard and doesn't spot the new one. Here, temporarily removing the other card's drivers did the trick, allowing it to be correctly spotted. Sometimes installing a new card when you already have another model from the same manufacturer in your PC can cause problems, as can installing driver updates that get only partially recognised, leaving a mixture of old and new driver files. Part of the problem here is that Windows isn't very clever at finding files inside other folders during an install, and this is why most manufacturers still recommend copying driver updates to a floppy disk before installing them, so that all files are in its root directory.

If you download new drivers from the Internet and then place them in a nested folder on your hard drive, even if you point to the first file required when prompted, Windows can sometimes ignore subsequent driver files in this folder if it finds older ones already in the Windows\System folder. The best thing to do in these circumstances is to completely remove the existing soundcard drivers as I described in PC Notes January 2001, or if available follow the step‑by‑step instructions provided by your soundcard manufacturer.

Sharing Interrupts

When your PC is stuffed full of expansion cards it's quite easy to run out of individual interrupts to service them, and this is why Microsoft first introduced Interrupt Sharing in Windows 95 OSR2. I described the process in detail in PC Musician in February 1999, but essentially it allows several expansion cards to poll the same interrupt. However, only PCI cards can share interrupts, so if you still have an elderly ISA card in your system, make sure this gets its own dedicated IRQ.

Since interrupt sharing has now been around for several years, you might expect it to help sort out lots of soundcard installation problems, but it still seems to cause as many problems as it cures. A few have traced these to specific motherboards including for instance Abit's BE6, but they're largely due to the design of individual expansion cards — some will happily share interrupts with others, but others won't, and I suspect this is why there is such confusion out there.

Unfortunately we come back to the same situation as with non‑Intel chipsets: some manufacturers tell you if their expansion cards support interrupt sharing, and others don't. For instance, RME and Soundscape are happy to claim 'complete interrupt sharing' in their spec lists, though of course if your Hamme rfall or Mixtreme card tries to share with another card that isn't happy about cohabiting you could still get problems. Other manufacturers are open about the fact that their products don't support IRQ sharing: Terratec, for instance, say in their on‑line FAQ that the EWS88MT/D models need their own interrupt.

The first advice most manufacturers give in this situation is to try swapping your soundcard to another expansion slot. Not only will this force the hardware to be re‑recognised, but the chances are that even if it still ends up sharing an interrupt, it may well be with another card that is more accommodating. A few words of warning here, though: each time you move a card to a new slot it adds entries to the Registry, and if you're not careful you can also get multiple Registry entries when updating drivers without uninstalling the older ones first. This can eventually cause problems, but I described a thorough solution back in PC Notes June 2000 using Safe Mode. In essence, if you find any multiple entries for the same device inside Device Manager you should delete every one, and then Windows will re‑detect them when you reboot and place a single correct entry in the Registry.

Another potential problem area is when using Creative's Soundblaster Live! series, which includes a Soundblaster Emulation that looks to your PC like an SB16 soundcard. Since this was an ISA‑based soundcard, it's unable to share IRQs or DMA with other cards, but at least you can disable it from Device Manager if you don't want to use it.

Multiple Cards

Back in 1999, many musicians were being forced to install multiple soundcards to run soft synths, since few multi‑channel soundcards had truly multi‑client drivers that allowed multiple applications to access separate output pairs simultaneously. Thankfully this situation has improved greatly, partly because of updated drivers and new cards like Echo's Mia that support up to four applications on a single output socket, but also because so many soft synths are now integrated with MIDI + Audio sequencers like Cubase VST, Logic Audio, and Sonar. However, many people still want to add a second soundcard, usually to add more audio inputs and outputs.

If you want to add more audio I/O then the ideal solution is to install an identical soundcard to the one you have already, since every input and output will then have exactly the same latency and sound quality, which makes mixing a far easier proposition. However, this will either work very well or not at all, depending on the way the drivers have been written. For instance, given their low prices, many people have been tempted to install more than one Creative Labs Soundblaster Live! card in their PCs to add more audio channels or SoundFont voices. However, this is normally doomed to failure, since Creative's drivers are only designed for a single card — if you try to install a second set of drivers they will simply overwrite the identically named driver files already sitting on your hard drive. Moreover, since you have two identical cards in your PC, and only one set of drivers, the chances are that either one or other of the cards simply won't work, or your PC might not boot up at all until you remove the duplicate.

Installing multiple identical cards in the same PC will only work if the drivers have been specially written to support this situation, and include a means of uniquely identifying each card. Quite a few of these now exist, including models from Echo, M Audio, and Yamaha, all of which will also let you run various combinations of card together from one set of drivers. However, before you buy another card from the same manufacturer, it's wise to check what's possible and what's not, since some restrictions may apply.

If you're going to mix completely different soundcards to add more audio channels, bear in mind that for best results you'll need to be able to set their latencies to the same value so that all the tracks emerge at roughly the same time. However, all converters have their own small latency, of the order of 1mS or so, which means that the inputs and outputs of different soundcards won't ever be perfectly locked together in sample‑accurate sync, even when clocked from the same source. Watch out as well for phase inversion — one make and model of soundcard may not only be slightly time‑shifted from another, but its outputs may emerge inverted. Issues like these are particularly important if you're trying to create a surround sound system. You should be all right as long as you use one soundcard for the front channels and another for the rear. The subwoofer channel isn't as critical, since low frequencies are more forgiving in this context.

Software And Multiple Cards

The final thing to consider before installing several soundcards is software support. Adding a second soundcard doesn't automatically cause your music software to send audio to appear from both simultaneously; you'll need to choose which audio tracks are routed to which soundcard in your MIDI + Audio application. Nearly all applications, apart from consumer Windows programs like Microsoft's Media Player and a few stand‑alone soft synths, offer such facilities nowadays, but there's another important consideration as well.

Multiple cards from one manufacturer all running from a single driver tend to appear inside software as a single larger device, which makes using most music software comparatively easy. However, there may still be limitations. For instance, Nemesys' GigaStudio can only currently access the first card it finds with GSIF‑compatible drivers. More limiting is the fact that Cubase VST still only lets you address a single ASIO device; even if you have multiple soundcards, each with low‑latency ASIO drivers, you'll only be able to use one of them unless you revert to the ASIO Multimedia or ASIO DirectX drivers, which of course will greatly increase latency. Here, Cakewalk's new Sonar scores highly, since you can get latencies down to 15mS or less even using standard MME drivers, and can therefore happily use several different soundcards side by side with low latency. Logic Audio also provides a neat way round this problem, by letting you run one card with ASIO drivers, another with EASI drivers, and even a third Audiowerk card simultaneously.

If you're interested in surround sound mixing then you can use any application that supports the appropriate number of output busses, but dedicated features such as surround pan controls for each audio channel and built‑in low‑pass filtering for the subwoofer channel will make your life a lot easier. Cubase VST doesn't yet offer these (although Steinberg's Nuendo does), but Emagic's Logic Audio Platinum now has them, as does the latest version of Magix's Samplitude 2496.