Amp Up: Give The MSI Five Channel Card A Shot
Jschoorl weighed in with his own positive experiences using the MS-4140 sound card, and indeed, there is an entire 75-page thread on AVS Forum dedicated to using Maui with the onboard D2 chip. I took a lot of heat in the first story for not testing the Maui platform’s amp. After all, as that same AVS Forum thread pointed out, this is the whole point of paying extra for this board is the D2/MS-4140 combination.
Admittedly, this isn’t something I really cared to do—after all, I had a capable receiver in place, and the speaker block on the back of the MS-4140 is, in my opinion, a mess. With no support for banana clips, you’re left clipping the ends of your speaker wire, cramming it into the end of the block, and hoping you’re not using anything larger than 14 gauge wire (maybe 12 gauge). Nevertheless, it was an oversight to think I could build the box up without testing that component as an option and not get some negative feedback as a result.
AMD’s Jay Taylor weighs in here with an observation and a suggestion. First, that high-density speaker block is actually an industry standard, allowing MSI to cram all of that connectivity onto a low-profile card if necessary. It’d take an OEM to design something more elegant at this point. And, for those who want to work around the quasi-nightmare of cabling, it’s completely feasible that you might run wires from the block to a wall-mount speaker bracket, preserving the use of banana clips from your passive speakers and cutting back on the mess.
Laying A Foundation On The DAE-3 Amp
The D2Audio DAE-3 has been lauded over and over for its programmability, flexibility, and quality. But up until now we haven’t seen Intersil really do anything to enable the goodness AMD’s home theater team has evangelized. But it’s a work-in-progress and AMD’s Taylor tells us that the platform is going to soon see its first major update. A little background first, though.
Why is this planned update so significant? Well, to begin, the Media Live Diva motherboard is being offered (with the 5.1-channel amp card) as a substitute for your home stereo receiver, so it really needs to enable functionality similar to what you’d expect from a $300 or $400 consumer electronics component (AMD actually thinks the value is closer to a $700 receiver). “But that’s ludicrous,” you say. “My receiver is a 50-pound beast loaded with huge caps and even larger heatsinks. There’s no way a PCI Express card and an onboard IC are going to match that.”
In fact, you’re actually talking about two different technologies there. Many stereo receivers employ analog Class A or Class AB (most common) amplifiers, which offer various levels of power efficiency versus sound quality, but most often, represent the large, heavy receivers to which you’re accustomed. They amplify the entire analog waveform, and are consequently favored by enthusiasts who claim they deliver warmer, richer sound.
D2Audio’s DAE-3 is a Class D switching amp that reproduces the audio waveform by sampling it digitally at a very high frequency. Because the technology has advanced far enough, you can get sound quality that rivals some of the best Class AB amps using Class D hardware now—this is what AMD, MSI, and D2Audio are trying to demonstrate here. According to D2Audio, the DAE-3 is 93%+ efficient compared to the typically 50%-ish efficiency of an AB amp. Consequently, less of the power it draws from the wall is dissipated as heat (purportedly about 10W under load), and that’s why it’s able to fit on a PCI Express card. Instead of the massive transformer and capacitors typical of most AB amps, D2Audio’s design uses a switched mode DC-DC converter for its power supply.
Interestingly, the 5.1-channel card with all of the amplification circuitry on it is spec’ed to deliver 5 x 100W of output, which you might find interesting given the 450W Corsair power supply we featured in Part 1 of this exploration. D2Audio makes it a point to emphasize the real-time power supply monitoring that goes on in its DSP. In essence, this feature keeps tabs on input voltages and, if draw from the amplifier appears to be on the verge of inducing a brownout or reset state, it’ll gracefully scale back draw (and output) from the amp until safe conditions are re-established. This is particularly important with a PSU rated for less output than the amp’s potential. However, I didn’t run into any trouble during testing—a testament to the quality of Corsair’s 450W offering.
