X-Fi and the Elite Pro: SoundBlaster's Return to Greatness
by Derek Wilson on August 30, 2005 11:59 AM EST- Posted in
- Smartphones
- Mobile
The X-Fi Audio Ring: Powerful and Flexible
Putting aside marketing buzz words and the slightly tacky Xtreme Fidelity moniker, the new generation of sound cards from Creative Labs is quite impressive. The technological advancements come from the inclusion of four key new features: the ring based architecture, a high quality sample rate converter, a powerful DSP, and on-board RAM. First on the chopping block is the Audio Ring.
Another reason why Creative may have chosen to support so many internal channels is so that it can handle algorithms that call for splitting or duplicating an audio stream for multiple different types of processing and analysis. This could range from using CMSS-3D (Creative's new surround upmixing feature) to efficient implementations of complicated high order N-tap and feedback filters. Creative doesn't talk much about the uses of these internal channels, but many of their new features include detecting aspects of the audio being played in order to enhance the sound. It seems likely to us that the algorithms that implement their new features would rely on the high number of channels and the flexibility of the ring architecture to get as much done at one time as possible in order to keep from introducing an unacceptable amount of latency.
Now that we know how the ring works, here's what each node on the ring does:
Transport: This handles moving audio streams in and out of local RAM as well as over the PCI bus to system RAM. The Transport engine manages over 1000 DMA channels to both the PCI bus and local SDRAM. Being able to manage so many DMA requests at a time is important for dealing with the latency of PCI and effectively managing the volume of data with which the new solution is capable of working.
Tank: Its name is based on the tanks that held mercury used to create high quality analog delay lines. The tank engine is capable of fractional and modulated delay lines (delays that don't line up with the sample pattern and delays that change over time). The tank engine supports up to 1024 accesses per sample. This means that the tank engine can assist in many types of effects including: chorus, reverb, reflections, and interaural time delays (for positional audio effects). These effects are employed quite a bit in many of the audio processing features of the X-Fi, so avoiding the use of a DSP for the creation of a delay line is very helpful in spreading out processing power.
SRC: The Sample Rate Converter seamlessly transforms any audio stream or channel to any other supported sample rate with very low ripple and THD+N. We will cover this node in detail as it is one of the key features of the new architecture, allowing Creative to convert the sample rate of all audio multiple times independently of any other audio with little to no discernable loss in quality.
Filter: The filter engine implements 512 floating point 2nd order IIR filters. This is the fundamental building block of sound synthesis, 3D spatialization, equalizers, speaker calibration, and a host of other features. There are 13 filter types implemented in hardware from direct and parametric 5 parameter EQs to notch and peak filters. Complex (higher order) filtering and synthesis can be achieved by looping through the filter engine multiple times until the desire result is achieved.
Mixer: Consisting of 256 audio summers, 1024 parameter combiners, and 4096 single segment parameter rampers, the mixer is where internal audio channels come together. Parameter mixing and ramping are used to control effects combining for things like 3D audio effects in game. Instead of single segment, the parameter rampers can also support either 1536 multi segment rampers or 4 multi segment shapes (possible shapes are linear, pseudo exponential, and pseudo logarithmic).
DSP: The X-Fi Quartet DSP is so named because it supports 4 hardware threads. Each thread has access to two SIMD (single instruction, multiple data) units for easy stereo and complex math processing. NVIDIA has called a multiple SIMD processing unit MIMD (multiple instruction multiple data), but Creative has dubbed the overall architecture TIMD (Thread Interleaved Multiple Data) due to the hardware threading support alongside traditional methods. The Quartet DSP is central to many of the X-Fi features and we will cover this hardware at length as with the SRC engine.
Audio I/O: This node handles moving the final processed audio streams to output either digitally or through a DAC, and can also acquire input from each of the source options on the hardware. Audio sources in memory do not enter the path through this node, and likewise for audio written to memory (or a file). This block manages all the physical I/O ports on the X-Fi card.
Having easy access to any of these structures at any time during audio processing will greatly simplify the process and increase the complexity of operations possible on X-Fi hardware. In order to further optimize the architecture, Creative has introduced three distinct modes in X-Fi. These modes outline the basic type of path that audio streams will take through the ring. For instance, professional audio programs require very low latency audio from the sound card when recording. In order to accommodate this, the Creation mode limits the types of processing done to less complex (and faster) algorithms. Creation mode also allows synchronized audio streams for proper integration into a studio setting. These features aren't necessary when in Gaming or Entertainment modes, as the focus of these modes is on generating or heavily processing audio before input or output.
Architecting the card like this isn't useful unless the nodes on the ring are powerful enough to exploit the potential. Creative has spent quite a bit of time in making sure that this is the case. Their components are high quality and introduce as little distortion and noise as possible in order to make heavy processing of audio on a consumer sound card a reality. (Whether this is really a good thing or not is still up to the end user.) Over the next couple of sections, we will cover the most important components of the audio ring, as well as explore what is possible when all of this hardware sings in unison.
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JNo - Thursday, September 1, 2005 - link
In fact, if Anandtech could do a review of the HDA X-Mystique 7.1 it'd be appreciated as I've heard quite a few good things about this card, not least its reasonable price point and dolby digital live output.By the way, on a separate note, for all the people here giving anandtech grief, people should look at more than just one site before making informed purchasing decisions and anandtech did much better than tomshardware which was extremely partisan. Also, I would like to use and trust dedicated sound sites like www.3Dsoundsurge.com but unfortunately they are often too slow in reviewing new hardware...
DerekWilson - Tuesday, August 30, 2005 - link
you can output sound digitally ... dolby sources (DVDs) can be output to a reciever, and audio can be output via SPDIF to a reciver as well ...What you can't do is take a source that's not already dolby (like music, games and the like), encode it to dolby, and then send it to a reciver.
Lwood - Tuesday, August 30, 2005 - link
I found this on the ALSA mailing list (http://www.gossamer-threads.com/lists/linux/kernel...">http://www.gossamer-threads.com/lists/linux/kernel...:"We are not going to get any support from Creative for the X-Fi chip.
We do not get support from Creative for any Creative chip that has a DSP
in it."
It looks like we won't see a Linux driver for the X-Fi anytime soon... :-(
sprockkets - Tuesday, August 30, 2005 - link
Oh well, even nVidia's soundstorm worked in linux, and with the 5.1 encoding out.Reflex - Tuesday, August 30, 2005 - link
I've had these cards in my lab and all I can say is that this is the first time I've ever really doubted Anandtech's credibility. This reads like a spiced up piece of PR from Creative, and subjective listening would not put this as the best consumer audio solution as so prominently stated on the first page of the review.Derek - What the hell is going on here? You don't even include any results from competing products to make such a statement. The war was over before a shot was fired is the impression this review gives. The fact that Creative finally has a card to match the specs that otehr cards have had for three years now makes it a 'revolution'? Sorry, I have been working with these cards for months now and they definatly are nothing special. Just expensive.
flexy - Tuesday, August 30, 2005 - link
100% agree...tried to keep my complaints back, tho.Btw. nice nick :)
DerekWilson - Tuesday, August 30, 2005 - link
Hello,We will be looking at more cards, and including an envy24 based solution is something that we intend to do in the future.
We do include a result from a competing solution -- the Gina 3G is a pro audio card which has excellent audio quality. The Elite Pro is closer to a pro audio product in the component selection and construction.
envy24 based consumer products don't score as well as the Gina 3G from what we have seen. Granted we do have to test this for ourselves, but we would certainly expect the Gina 3G to outperform something from Terratec or M-Audio.
That being said, the X-Fi outperforms the Gina 3G in just about ever test we ran.
It is very difficult to subjectively compare audio between cards. There have been some cases (the audigy line) where there was a very clear problem with the aural experience. With the X-Fi line, we can no longer say that we can hear problems with the audio.
We spent days listening to this card, the Gina, and the Audigy 4. We frankly disagree with the statement that subjective listening does not put this card on par with the best audio solutions out there. We found no reason in our subjective listening tests to conclude otherwise.
On top of that, after simply listening to the card for days, we ran the RMAA tests. These tests showed clearly that not only was the card void of any issues, but that the quality of the output was much closer to the source than any other card we tested. These two points add up to the conclusion you disagree with.
And as we said, if this card performs better than the Gina 3G and the Gina performs better than consumer level envy24 parts, it stands to reason that the X-Fi would outperform just about everything but a LynxTWO ... and even then we would need to run some tests of our own ...
The big problem is that at these incredibly low noise levels, high dynamic range, low distortion, good separation, etc... it is very difficult to hear differences in the audio. To the average person, the audigy 4 Pro, Gina 3G, and X-Fi will sound exactly the same. To a hardcore audiophile, we wouldn't doubt it if the X-Fi won their hearts. The X-Fi (in spite of its features) can provide a very true-to-the-source signal with less coloration than all but the best pro audio cards out there.
For musicians, the high quality provides a better platform for work than the rest of the pack -- unless, of course, balance audio is desired.
Show me a consumer audio card that matches the specs of the X-Fi ... From the tests other people have performed on the LynxTwo B at 16-bit/44.1kHz (the unofficial standard in PC audio quality), the X-Fi posts http://audio.rightmark.org/test/lynx-two-b-1644.ht...">better numbers in every category but frequency response (and it's darn close in that area)...
The high end components used do not make the X-Fi Elite Pro "nothing special" ... They make it nothing most people will need. And certainly, between this and other products that use good quality components, most people won't notice much (if any) difference.
We very much agree that the card is too expensive. And please rest assured that we will be comparing this card to an evny24 based solution -- and hopefully a lynxtwo -- in the future.
Thanks for the feedback,
Derek Wilson
yacoub - Wednesday, August 31, 2005 - link
Look into the BlueGears X-Mystique. It's pretty much the best PC soundcard available at a reasonable price right now - and it's not Creative so there's no assorted bloatware to install.Reflex - Tuesday, August 30, 2005 - link
Derek -I am not trying to bash you here, however you have to understand that when you start an article by proclaiming something the best in its class, but then your test does not include the other solutions in the class at all, that things seem fishy.
I work with audio devices for a living. I've worked with the X-Fi since it was a prototype(as have a couple dozen other people in my lab). Certainly it is an improvement over previous Creative efforts, and at first we were a bit wowed by the paper specs and proposal. However after working closely with it for months, I honestly can say that no one here feels its anything special. Perhaps some of that is the novelty wearing off, but in any ad-hoc test with someone who hadn't heard it before, they could rarely tell the difference between it and an Audigy, and the M-Audio Revolution generally was said to produce clearer sound. Not that our tests were scientific or anything, we weren't trying to write articles for publication.
I'd really suggest some blind tests with a variety of content. I think you may be suprised to find that while for MP3's the X-Fi sounds good, for CD's and especially SACD's the mid-range is poorly reproduced. Make certain you use a wide range of music, and prefferably classical numbers that you know very well.
Something else is you could list what type of speakers/headphones and recievers you are using, if you are testing with something like Klipsch then your credibility would go down considerably for anything but games and action movies, after all the card cannot make up for poor speakers(when measured by reproduction accuracy, not volume).
I would suggest establishing a baseline and going from there. Based on my experience, in the 'consumer' segment the M-Audio Revolution 7.1 is a good baseline, however any baseline that you could compare against would be beneficial to strengthening the credibility of the review. Granted anything audio is subjective, but when you say something is 'better' you need to at least be able to point to some specific reasons as to why.
And finally, the section that read like Creative marketing PR was your explanation of their audio architecture. There is nothing inherantly 'better' about the approach Creative is taking, it is simply different, there are both advantages and drawbacks. Furthermore, while they make the product seem like the 'next generation of audio' no one has managed to get a commitment from them to support the upcoming Windows Audio Architecture that will be a part of Vista, without that support they will be behind several others. Their lack of support for Linux is also a drawback for many.
Thank you for the effort, I hope that this feedback will help you improve your audio reviews in the future. I have read AT since the beginning and rarely doubted what is posted here, there just seemed to be some rather glaring flaws in how this review was handled. At least in my humble opinion.
DerekWilson - Wednesday, August 31, 2005 - link
Thank you very much for the helpful feedback. Some of your suggestions will absolutly make it into future audio reviews.I would tend to disagree with your assesment of Creative's architectural direction. If the intent is to very heavily process many audio streams, then the flexibility and power are helpful. This could be a boon to game designers or electronic musicisans looking for some hefty sample rate or dsp power.
For straight up listening to a single source or recording the architecture is unnecessary.
I agree that windows driver and linux support are drawbacks as well.
We absolutely appreciate and need our readers feedback. Thanks for taking the time.
Derek Wilson