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OC-Master
11-13-04, 04:13 PM
M-Audio Revolution 7.1 X1 Express
Creative Sound Blaster Zenith
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If your planning on upgrading your motherboard, make sure you got at least one X1 PCI Express slot so that you can expand to higher end sound cards in the near feature.

Both M-Audio and Creative are launching PCI Express sound cards that have DSP's that are five times more powerful than that in the Revolution 7.1 and AudigyII ZS.

Although Creative Labs refuses to comment on unannouced products, its very likely that we'll see a large FPS boost in our favorite games when running HD 24-bit sound in 5.1 or 7.1 with an X1 Express card over the legacy PCI sound cards.

If you can remember back to the days of ISA, PCI sound cards gave massive boosts in performance to PCs for all multimedia. People say that PCI (133MB/s) is enough to fill the needs of the sound department of the PC but to what degree? Is it fast enough to transfer a 20MB sound file instantly without a hickup in audio quality?

So I decided to do some math in the bandwidth department.

Bits / Eight = Bites X Frequency = 1 Sound Channel X no. of channels = Total Bandwidth Needed Minimum

Streaming audio directly to your sound card takes up...

Standard CD's need roughly 176.4KB/s (16/8=2X44.1=88.2KB/s Mono X 2 = 176.4KB/s) (150~200KB/s)(1X CDROM) to play CD Quality music. Doesnt sound like much but lets add six more channels at CD Quality. So that 16/2=2X44.1=88.2KB/s Mono X 8 = 706KB/s to play CD Quality 7.1 sound.

OK, lets add 24-bit 44.1kHz 7.1 into the mix..
24/8=3X44.1=132.3KB/s Mono X 8 = 1059KB/s to play 24-bit 7.1 sound.

Now lets add in 96kHz to the mix to make the sound a little crisper. All the Audigy cards can do 96kHz playback for reference sake..
24/8=3X96=288KB/s Mono X 8 = 2.3MB/s to play 24-bit 96kHz 7.1 sound.

Finally, lets do what no one has done before, lets use 24-bit 192kHz 7.1 . To date, no cards can do this reason being because it simply takes too much processing power for the DSP to handle.
24/8=3X192=576KB/s Mono X 8 = 4.6MB/s

4.6MB/s for the ultimate (BASIC) sound quality. So why doesnt this standard exist yet? Probally because most people probally cannot hear the difference and or Sound Card manufacturers have not gotten DSP's fast enough to process sound at this quality level.

EAX, Dolby and DTS all play big roles in amount of bandwidth consumed. Dolby uses about five times the memory to run its format. Being that, per channel you'd be looking at about 23MB/s for 7.1 24-bit 192kHz Dolby sound. DTS uses even more bandwidth, about twice that of Dolby according to Mpeg-2 specifications.

Thanks to compression, a 46MB/s DTS stream becomes 20x less in Mpeg2 making it only 2.3MB/s for 192kHz or 1.15MB/s for 96kHz.

EAX on the other hand uses little or no bandwidth because all sound is processed in the DSP of the sound card in realtime. With PCI Express, instead of having to uncompress the DTS/Dolby sound with the processor, the signal can by pass the CPU and go directly to the sound card. Rumors have it that PCI Express sound cards will come with onboard cache memory whether cached into the DSP or onboard. This would allow for a complete dump of an operation in one task and give oodles of space directly from the ram allowing the whole stream to play flawlessly.

PCI-Express allows your sound card to access your RAM without even having to pass through your CPU unlike PCI sound cards. This is where you see your FPS gain in almost any task relating to sound be it gaming or for studio use.

To make all this jiberish simple, think of PCI Express sound cards as an AGP port. You can cache with your ram on your machine for any sound related materials.

But untill these cards exist, we are all fine with today's PCI cards. BTW, Express cards should be cheaper because the boards are alot smaller which in turn means less circurtry.

I'd like to thank my dad for lending me his Sony Dolby Digital sound guide and for his advice in the studio department. I my self am a PC DJ and I love mixin on the PC.


OC-Master

JeffP
11-13-04, 04:20 PM
Good info. Thanks for the heads up.

eduncan911
11-13-04, 04:50 PM
Humm. WHere can I get one of these cards? I see the Creative Labs you commented on isn't out yet.

My new handy dandy Asus P5AD2 Premium with 7.1 surround onboard, litterly sucks donkey *$#%@. I'm sure it's a good onboard sound, as it has optical out and all. But the drivers are an absolute nightmare. It seems the WAV drive is single threaded only, and the drivers don't remember my selection to 5.1 audio on reboot.

Not to mention the pops and creeks from EMI interference (reseated the board three times, used shielding between HD and mobo for testing, nada).

I'm sick of it. WOuld rather have a good sound card. I'm limited in space, so I was thinking about the USB 2.0 versions from Create Labs with surround sound.

Maybe I should live with what I got for now until the PCIx versions come out soon.

Maxvla
11-13-04, 05:33 PM
x1 is the little slot right? pretty much any pci express board is going to have several.

eduncan911
11-13-04, 06:05 PM
x1 is the little slot right? pretty much any pci express board is going to have several.
Yep, my mobo has two 1x PCI-E slots (see post above about what board I have), along with the one 16x PCI-E slot. :D

Problem is, this mobo wants to take up 4 additional expansion slots in your case for the additional items that can't fit on the back mobo panel (it's a heck of a full-featured mobo). Right now, my PCI-E 1X slots are covered by the only 2 case slots I have left. This is going to get tricky!

OC-Master
11-13-04, 06:14 PM
Humm. WHere can I get one of these cards? I see the Creative Labs you commented on isn't out yet. eduncan911

http://www.vr-zone.com/?i=1430&s=1

According to VR-Zone, CreativeLabs is launching the Zenith series in March next year. I feel this is about the right time to launch a new product based upon this next connectivity hence most people who have new PCs will be able to upgrade to the futuristic sound device.

M-Audio is supposed to have X1 version's of their already popular card by early January.


OC-Master

eduncan911
11-13-04, 06:16 PM
So who's the cutie in your avatar? :D

Voodoo Rufus
11-13-04, 08:54 PM
Interesting. I'm curious as to what features are going to be in these new DSPs that make them "5x more powerful".

Now all we need is ram on sound cards....

OC-Master
11-14-04, 09:44 AM
Interesting. I'm curious as to what features are going to be in these new DSPs that make them "5x more powerful".

Now all we need is ram on sound cards....

I'm gonna take a wild guess, alot more MHz on the DSP (Audigy II ZS was 250MHz) so I'm gonna guess 750MHz or higher, internal cache, faster interconnects, higher dacs which produce crisper sound and most importantly more accurate hardware acceleration.

Creative also mentioned something a long time ago that they wanted to implement full hardware encoding of sound streams from all Mpeg standards (MP1,MP2,MP3 & MP4) which would cut compression times by 80% in some cases.

Compressing a 80min wave file to MP3 with my PC takes 10 Minutes at 256KBPS. The Zenith cards should cut that time down to 2 minutes or so.

What actually happens is the sound card takes wave file and encodes it directly to MP3 in your system ram, something today's sound cards cannot do directly, offloading most of the workload from your PC.

Lastly, the ability for the sound card to encode MP2 audio and MP4 audio means a huge cut in compression times for people that video edit and work with Mpeg video.


OC-Master

9mmCensor
11-14-04, 02:43 PM
So who's the cutie in your avatar? :D
i think he changed his avatar... :beer:

SK8
11-14-04, 02:47 PM
Do i smell glue...Sticky!

JeffP
11-14-04, 02:57 PM
i think he changed his avatar... :beer:

bahahaha. I certainly hope so or we have a tuty fruity on here.

eduncan911
11-14-04, 03:24 PM
bahahaha. I certainly hope so or we have a tuty fruity on here.Yes, he did change it. :P It was a pic of a "girl" thank you much. LOL