Driver Issue

Just musing on the differences

Hi there,

We are constantly bandying around the various driver acronyms … MME, WDM, ASIO etc. … and even after 3 and a half years of recording with n-Track I’m still not sure I have a handle on what the differences are.

Sure, I know that MME are the oldest type, WDM was introduced by Microsoft as part of its OSs, and ASIO is another Steinberg standard, like VST, but what does it all mean?

My PC has an onboad soundchip using the classic AC’97 codec, and I record using a Yamaha UW500 USB device - works really well and eliminates the excessive noise inherent in my onboard.

The UW500 has ASIO drivers that have never really worked for me at all, WDM has until now always worked pretty well, and MME has provided a reliable backup if something goes wrong.

However, having reinstalled my OS (WinXP Home) and all the software, and upgraded to N-Track 4 (never having installed v3 on the re-installed setup), I find that the only one I can get to work reliably is MME.

It works great, so the system is useable, and everything works the way it should, but I am somewhat intrigued as to what has happened, or what could be going on, and I realise that I probably don’t know enough about the workings of these things to get a handle on it.

Anyone prepared to offer some comments on what it is all about?


This is a good question, IMHO, and it makes me want to go dig up a precise, technical, detailed, answer! :D It’d be nice to really understand the limitations, strengths, weaknesses, etc. of each driver type–could make troubleshooting easier…

For starters, here’s some cut-n-paste from a Google cache of a page (which seems to be down right now due to unpaid bills or something):


MME stands for MultiMedia Extension that is a part of Windows that sets the rules for recording and playing back audio. It is typically used since the 1st Windows 3.0 systems as a default. It’s slower because it is controlled by the operating system. Each soundcard maker had to write a .DLL file for the card to use the MME. These varied quite a bit in performance. Today, rule of thumb is not to us MME drivers in audio applications, unless the soundcard maker took the pains to develop and excellent driver. They usually don’t.

ASIO is short for Audio Streaming Input/Output This is an “open standard” developed by Steinberg for minimizing latency with virtual studio applications. where multiple streams of audio are processed. It has been adopted by Emagic and other software makers. There are 2 versions. ASIO 1.0 and 2.0. 2.0 adds the ability to monitor several audio inputs at once.

WDM stands for Windows Driver Model with Kernal Streaming This is a newer, lower latency driver that allows the application direct access to the “kernal” without going through the Windows OS. This results in latency figure that is fast like ASIO. It was introduced in Cakewalk’s Sonar. So if you want to run Sonar, a card with a good WDM driver helps. However, today cakewalk does support asio drivers.

Direct Sound came about around the time of Windows 95. It has the advantage of being able to playback softsynths with faster latency. However, Direct sound cannot record audio, it can only play it back, So if you plan to to audio recording, it is not a good choice. So, you dudes that write me and say “Can’t (explicative) (explicative) RECORD!” Check to see if DS is ticked. Don’t use it.

That statement about WDM being “introduced in Cakewalk’s Sonar” must be referring to music apps only, because Microsoft created WDM.