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XPlosion: Real-time DTS Encoding Sound Card! - Page 6

post #151 of 1054
That HL2 patch was issued a while back. Some DDLive solutions needed it to work correctly, but the X-Mystique never had the problem. The X-Mystique did have problems with Far Cry, but that was later fixed (same issue as HL2). Supposedly the game developers didn't follow spec with the DirectSound filter.
post #152 of 1054
Thread Starter 
Hi, Jerry!

The replacement Burr-Brown OPA2604AP opamps arrived - thank you very, very much! I popped them into the X-Mystique, fired everything back up, and was blown away! Remember the poor analog frequency response curve for the stock op-amps? As a reminder, here it is again:



Well, you're not going to believe what an enormous difference replacing the op-amps makes. Check this out!



I'm absolutely blown away by this! It's very obvious that the compensation on the board is wildly incorrect for this part. Whoever in operations decided to cost-reduce the board by swapping the opamps out for cheap parts apparently chose not only a real POS, it's also clear that it isn't in any way a direct substitute, other than being pin-compatible. As a result, the message is quite clear: changing the opamps to the recommended part makes a huge difference in frequency response!

What's particularly intriguing to me is the "60 Hz notch filter", which doesn't even exist! My earlier conjecture about it was obviously completely wrong, for I'd never expected that the notches we saw could be caused by swapping out a different opamp. Please accept my apologies for this mistake!

Now, unfortunately, the news isn't all good. Despite the huge improvement in frequency response, the distortion doesn't change significantly. Here's the original THD results from the stock opamps:



...and here's the THD with the Burr-Brown OPA2604AP opamps:



As you can see, the distortion levels are quite similar. Also, while I didn't bother posting it, the EFQPSK plots are essentially identical. While these results indicate that the digital outputs are in fact superior (at least with a good receiver), the results also indicate that if you're interested in the analog outputs, it's really important to upgrade the opamps!

Thanks, Jerry, for giving me the opportunity to test this! Your perseverance certainly payed off, and the results were very surprising, indeed. Well done! Thank you again for the opportunity to test the updated parts - it really does make a big difference!

By the way, are you sure that you don't need these back?

Cheers!
MarKF
post #153 of 1054
Thread Starter 
Hi, Gang!

Well, I started my first tests with the X-Fi, and the results are truly strange. It's basic parameters are incredible, with amazingly good THD and frequency response, but once we move to the EFQPSK dynamic response test, things look poor, indeed. I've posted the details in an X-Fi thread here.

FYI!
MarkF
post #154 of 1054
Quote:
Originally Posted by Mark J. Foster View Post

Hi, Jerry!

The replacement Burr-Brown OPA2604AP opamps arrived - thank you very, very much! I popped them into the X-Mystique, fired everything back up, and was blown away! Remember the poor analog frequency response curve for the stock op-amps? As a reminder, here it is again:



Well, you're not going to believe what an enormous difference replacing the op-amps makes. Check this out!



I'm absolutely blown away by this! It's very obvious that the compensation on the board is wildly incorrect for this part. Whoever in operations decided to cost-reduce the board by swapping the opamps out for cheap parts apparently chose not only a real POS, it's also clear that it isn't in any way a direct substitute, other than being pin-compatible. As a result, the message is quite clear: changing the opamps to the recommended part makes a huge difference in frequency response!

What's particularly intriguing to me is the "60 Hz notch filter", which doesn't even exist! My earlier conjecture about it was obviously completely wrong, for I'd never expected that the notches we saw could be caused by swapping out a different opamp. Please accept my apologies for this mistake!

Now, unfortunately, the news isn't all good. Despite the huge improvement in frequency response, the distortion doesn't change significantly. Here's the original THD results from the stock opamps:



...and here's the THD with the Burr-Brown OPA2604AP opamps:



As you can see, the distortion levels are quite similar. Also, while I didn't bother posting it, the EFQPSK plots are essentially identical. While these results indicate that the digital outputs are in fact superior (at least with a good receiver), the results also indicate that if you're interested in the analog outputs, it's really important to upgrade the opamps!

Thanks, Jerry, for giving me the opportunity to test this! Your perseverance certainly payed off, and the results were very surprising, indeed. Well done! Thank you again for the opportunity to test the updated parts - it really does make a big difference!

By the way, are you sure that you don't need these back?

Cheers!
MarKF

Hi Mark,

No need to apologized thats the great thing about this forum that we all contribute to this hobby and I really appreciated your time and effort to test the OP amps that I sent you, the result of the test that you shown us is very good news to all those out here that uses analog out. By the way you can have the OP amp that I sent you, I replaced my OP amps to Burr Brown OPA2134PA. The Bluegears recommend to use Burr Brown OPA2134PA since its design for audio applications with Sound Plus audio performance. I checked the data sheet on OPA2134PA and OPA2604AP and its look like the specs for OPA2134PA has better improvement on THD. See link of the Texas Instruments datasheet below.

Now I have my wallet ready for Bluegears XPlosion that is coming out next year

http://focus.ti.com/lit/ds/symlink/opa2134.pdf

http://focus.ti.com/lit/ds/sbos006/sbos006.pdf

Have a great holiday.
Jerry
post #155 of 1054
Do OPAMPS affect the SPDIF output as well? I'll be using the DDL/DTSC via SPDIF only so I'm curious if the extra $$$ for the X-Plosion over the X-Raider will be worth it for me.

Thanks.
post #156 of 1054
Thread Starter 
Hi, Stoked!

Nope, the opamps won't have any effect at all on the quality of the S/PDIF output, which is a simple digital signal. Now, it's possible that the opamps will have an impact on your ability to monitor the analog Line-In signal for testing, but as we've seen, the analog inputs are already good enough to determine the output quality - at least with the X-Mystique. Replacing the opamps is really only necessary for folks that are running with analog outputs to their receiver.

Cheers!
MarkF
post #157 of 1054
Is replacing the op-amps a complicated thing to do?
I checked the price and it seems that it would only cost a few dollars worth of chips...

Thanks,
Arno
post #158 of 1054
Quote:
Originally Posted by cooltalkingfrog View Post

Is replacing the op-amps a complicated thing to do?
I checked the price and it seems that it would only cost a few dollars worth of chips...

Thanks,
Arno

Its not hard at all you need an IC puller to take the old one just be carefull this OP amps are sensitive to static discharge also make sure to check pinouts that you dont reverse inserting them.

Jerry
post #159 of 1054
Thank you for the info.
Not ready to do anything at this time, but I was just curious.

Arno
post #160 of 1054
Thread Starter 
Hi, Guys!

It looks like Bluegears isn't the only one that's using this chip. Search e*bay for "C-Media 8768", and you'll find a once-a-day auction for a little cheapie card that uses the chip. Since I'm so anxious to find out how DTS Connect's going to perform, I bought the one yesterday. Once it's here, I'll post my test results!

Have Fun!
MarkF
post #161 of 1054
Quote:
Originally Posted by Mark J. Foster View Post

Hi, Guys!

It looks like Bluegears isn't the only one that's using this chip. Search e*bay for "C-Media 8768", and you'll find a once-a-day auction for a little cheapie card that uses the chip. Since I'm so anxious to find out how DTS Connect's going to perform, I bought the one yesterday. Once it's here, I'll post my test results!

Have Fun!
MarkF

Interesting. That card it pretty damn cheap, even with the expensive shipping. When do you expect it to arrive Mark?
post #162 of 1054
Thread Starter 
Hi, Stoked!

With the Christmas holiday, it's honestly hard to tell, but I did spring for 2nd day air shipping. If they get it out today, as they should, I ought to have it sometime this week.

Cheers!
MarkF
post #163 of 1054
The title says 7.1 but the description says:
"Package includes"
6-Channel PCI Sound Card...

I hope that this is just a typo...

Arno
post #164 of 1054
Quote:
Originally Posted by Mark J. Foster View Post

Hi, Stoked!

With the Christmas holiday, it's honestly hard to tell, but I did spring for 2nd day air shipping. If they get it out today, as they should, I ought to have it sometime this week.

Cheers!
MarkF

Sounds good Mark. Looking forward to your review. If it's a decent card I think I'll just pick this up. I noticed ST Labs doesn't have it listed on their website yet, I emailed them for more info though. No driver's listed either.
post #165 of 1054
Quote:
Originally Posted by stoked View Post

No driver's listed either.

That is what bothers me the most...
Of course, as soon as Mark gets it and tells us how incredible the card is, it will sell for $129 on ebay...

Arno
post #166 of 1054
Thread Starter 
Hi, Folks!

To be clear, I don't have particularly high expectations for this card, but it should be sufficient to test the DTS Connect feature. Among other errors, the website lists optical S/PDIF inputs and outputs, neither of which appears on the card. In addition, the analog circuitry doesn't look particularly impressive, at least from the photo on e*bay. Heh, it's just a cheap experiment. Still, it ought to be fun to play with it!

Cheers!
MarkF
post #167 of 1054
With all the detailed analysis of the Bluegears card in this thread, I'm suprised that no one mentioned a fairly big performance fault (particularly for audiophiles). When you fire up a stereo source and the card starts to convert it into DD Live, there is a noticable lag before you hear the audio (when using the digital SPDIF output) . The first 1/2 second or so of audio is clipped (not delayed, actually ommited). Perhaps this depends to an extent on the decoder on the A/V receiver you use (mine is old) but I also read about this in a review of the X-Mystique 7.1. I have the X-Mystique and I love it -- but I'm not an audiophile. Just thought I should mention this...

Dan
post #168 of 1054
Here's something from a review about the issue mentioned above:

"3) Sound being cut off with short clips with DDL: When DDL encoding is enabled, users may notice the start of a sound file is missing. This happens as DDL is not "enabled" all the time, it only kicks into gear when music/sound is being played. As a result, the delay in the kicking in may cause the first 0.3 second of the sound to "disappear". Currently, there are no known ways of getting around this bug.

Note: DDL seems to keep "working" for a period of time after playing a sound file. Thus, users generally will not notice this bug. Also, this bug is not noticeable in games or any continuous playing modes."


SOURCE:
http://www.overclockers.co.nz/ocnz/r...00mystic070404
post #169 of 1054
Thread Starter 
Hi, DanC-P!

This is easy to fix. Just enable "Magic Voice", but leave the other controls where they are so it doesn't interfere with the audio quality. That leads to full-time Dolby Digital encoding, and no more sound gaps!

Cheers!
MarkF
post #170 of 1054
Quote:
Originally Posted by Mark J. Foster View Post

Hi, DanC-P!

This is easy to fix. Just enable "Magic Voice", but leave the other controls where they are so it doesn't interfere with the audio quality. That leads to full-time Dolby Digital encoding, and no more sound gaps!

Cheers!
MarkF

Wow! I'm glad I posted my gripe :-). I'll give this a try tonight. Thanks Mark!
post #171 of 1054
I noticed that the C-Media web site says the following:

Dolby Digital Live 5.1 (AC-3) Real-time Encoder (only 8768+)


Notice the "only 8768+" part. The ad on E-bay calls it just the "8768". I wonder if the seller on Ebay screwed up and either forgot the "+", or if the card they are selling actually isn't the one with DDL?
post #172 of 1054
Thread Starter 
Hi, Davin8r!

Good catch, and good question! Since I'm interested in the DTS encoding capabilities, it won't make much difference to me, but other folks should keep their eyes open. Obviously, once mine shows up, I'll let folks know its capabilities!

Cheers!
MarkF
post #173 of 1054
Quote:
Originally Posted by Mark J. Foster View Post

Hi, Boiler11!

There are several reasons that I believe this is done in hardware, primary among them that Dolby Digital encoding on the X-Mystique takes almost zero horsepower (as documented by frame rate testing by a number of different gaming forums), as compared to other "Dolby Digital Live" software encoders. From this, as well as the press releases by DTS, C-Media, and Realtek, I've concluded that the DTS encoding will be in hardware, too.

I'll make sure that I add a performance test, just in case my conclusion isn't correct (I'm willing to bet you $10 it is, though ).

Have Fun!
MarkF

Just wanted to point out that although the mystique is doing the encoding on hardware, and the CPU usage is certainly lower than all onboard sound solutions. The CPU usage during gameplay is still noteably higher than on the Audigy line of sound cards. Not sure why this is, but I would speculate that's it's a driver issue.

I think this increased cpu usage (relative to the audigy) is why everyone thinks the card is doing the encoding in software.
post #174 of 1054
Quote:
Originally Posted by DanC-P View Post

Wow! I'm glad I posted my gripe :-). I'll give this a try tonight. Thanks Mark!

Eureka! It works!
post #175 of 1054
hi every one
i`ve been using creative labs < sound blaster 5.1 platinum > for along time, 2 speakers out to direct 6 on amp HK.
it sound good for long time.because i gave up on going coax out from sound card to reciever DTS, due to the high pitch and drops in sound, i thought it was wireing issue so i changed that, i thought the software i replaced it but the problem still there , then i swaped the motherboads with the one has ac97 realtech cmi chip witch has spdif out composite . then wow its great DTS sound now no high pitch no drop in sound,
so i put all creative labs sound cards in box with black ribon around it.
i know there is no difference in spdif pass throu in sond quality, but i still think is how the sound is routed on sound card specially if it passes through chip will still make a different.

i`m waitting for mark conclusion on DTS from explosion. great thread mark
post #176 of 1054
Thread Starter 
Hi, Gang!

Flashbacck: I've noticed that in some reviews (combinations of game + sound card), but not in others. Just to take a guess, I wonder if the CPU utilization is higher because the games are attempting to do software "replacements" for the EAX3/EAX4 capability that the Audigy cards offer in hardware, but that the X-Mystique doesn't? That's one area where Creative's got a lock on the market, since they invented it, but as was mentioned earlier in this thread, they're only licensing out the older EAX2.

DanC-P: I'm glad to hear that it's working! To give credit where credit is due, though, it wasn't me that came up with this one - I'm just repeating a message that was delivered by one of the HiTeC folks here on this forum a while back.

Safaa: Your observations do make sense. In your case, it sounds as though the poor DTS pass-through results may not have been caused by the "bits" being bad, but by Radio Frequency Interference being injected into the receiver. Those kinds of high-pitched squeals and aliasing are fairly typical of RFI, which can trash your sound no matter how good the bits are! Fortunately this is getting to be a fairly rare event, but if other folks encounter similar problems, and if you have a choice between optical and coaxial, it's worth giving the optical input a shot, since it will eliminate any possible RFI that the coaxial connection could be introducing. Like you, I can't wait to try out DTS Connect! Thanks!

Have Fun!
MarkF
post #177 of 1054
hello
i forgot to mention that i used optical in\\out to receiver from sound card front panel to no good,
on the net the are some complains in that issue of high pitch and drops.
then again if realtech cmi chip fix this problem , it was creative labs issue .i`ve tried every thing with sound blaster .but i`m set for cmi now.
sound blaster was ok on DD not DTS.which i`m after.
To be at extreme i did not get a coax cable nor composite video cable to connect coax spdif. i used cable box cable coxial with composite adapters at both ends.
its 75 Ohms. it sound great, but i want to see if better chip will enhance the sound.
thank you
post #178 of 1054
Thread Starter 
Hi, Folks!

Shoot! Well, folks, I should have noticed the discrepancy between the chipset I'd mentioned in my first post (the CMI 8770) and the one for the ST Lab card (the CMI 8768). Despite the claims on the e*bay listing, this card offers neither Dolby Digital Live nor DTS Connect. It's just a "dumb" PCM-only card with S/PDIF passthough. Don't waste your money - I've already contacted the vendor asking them why I shouldn't report this as fraudulent to e*bay.

Oh, well, it's at least partially my fault, but they did claim that this supported both Dolby Digital Live and DTS Connect. Darn - live and learn.

Best Regards,
MarkF
post #179 of 1054
Thread Starter 
Hi, Folks!

I'm temporarily using an M-Audio Revolution 7.1 audio card, using Winamp with kernel streaming for bit-perfect playback. After all this technical evaluation, it was finally time to relax a bit on Christmas eve and enjoy some music. So, I fired up a couple of DTS CDs, including Steely Dan's Gaucho, and Sting's Nothing Like the Sun. Winamp reports these discs as having a DTS bitrate of 1440K bps, so they're essentially the same bitrate as the XPlosion and X-Raider cards. Since I'd recently upgraded to a 7.1 system, taking the time to listen to these was an extra-special treat!

What terrific sound! I apologize that I can only offer qualitative assessments, but the sense of envelopment and immersion in the sound field was really amazing (duplicating the side surround outputs to the rear surrounds). However, I then turned on the Audyssey room correction capability, and just about fell out of my chair! I've never experienced sound like this! What Audyssey does is to equalize each speaker individually for flat frequency response, but it also measures the distances to each speaker, and sets up relative delays for proper speaker phasing. The resulting sound field is phenomenal! Listening to Gaucho is like sitting in the middle of the band, with precise 3D locations for each instrument - talk about a sense of reality! But what's truly astonishing is listening to the precise complexity of Sting's Englishman in New York, or the carefully crafted, almost tangible sound field of Fragile. Wow!

As I'd mentioned earlier, I don't claim to be an audiophile, but this sound is superb. It's my opinion, anyway, that DTS at 1.5M bps is capable of delivering truly awesome music quality! Now, whether the implementation in the XPlosion and the X-Raider can match this is a different question, but as a transport, high bitrate DTS rocks!

Merry Christmas!
MarkF
post #180 of 1054
Thread Starter 
Hi, Gang!

I just found a terrific list of Region 1 DTS DVDs that lists audio bit rates, as well as noting those discs which contain DTS-ES 6.1 audio tracks. On top of that, SpannerWorks also has a list of Dolby Digital Surround EX and DTS-ES DVDs. Good stuff for taking advantage of those shiny new 7.1 systems!

Happy Holidays!
MarkF
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