»

[save2600]

Wondering how Deneb would handle this card:

USB sound card

...or this one:

another USB Soundblaster linky

Could these be used as an alternative to the mp364 doo-dad or ahi.device, allowing better fidelity for mp3's, etc? Does Poseidon (I have the latest version) already support these? I suppose a game or demo would have to be written specially for 5.1 surround, but for $10 more, that card does have better audio specs as well.

[beller]

It appears that the current version of Poseidon supports this via the usbaudio.class driver. Chris describes this as supporting audio streaming for USB soundcards, headphones etc.

Given the description, I think the Soundblaster should work...but then I've been surprised before!

Bob

[save2600]

Cool, kinda figured Deneb would perform the basics at least, so thought I'd give one of 'em a try. The $60 model has a "state of the art" 24-bit 96khz converter in it, but can't find the D/A details on the simpler one. Our local and small-concept Best Buy is out of it though, so will give it a try some other time. Thanks for the input.

[beller]

Let me know how it works. I might want to get one myself!

Bob

[platon42]

save2600 wrote:
Could these be used as an alternative to the mp364 doo-dad or ahi.device, allowing better fidelity for mp3's, etc? Does Poseidon (I have the latest version) already support these? I suppose a game or demo would have to be written specially for 5.1 surround, but for $10 more, that card does have better audio specs as well.

The usbaudio.class only supports mono and stereo (playback and recording), but it does it for 99% of the soundcards out there.

There are no 7.1 channel applications, hence the class does not try to use multichannel modes like 5.1 or 7.1. AHI has a limit of 65KHz (16-bit word) sample rate, so the usbaudio.class will filter higher supported frequencies.

Only PCM is supported, a potentially existing hardware decoding function for MP3 is not supported.

The usbaudio.class only works with the Deneb, not with any other USB card (because the driver needs to support realtime ISO transfers).

[save2600]

Once again Chris - thank you for the tech specs here. Glad to know usbaudio.device has a 16-bit wordlength limit. No need to fuss trying to get 24-bit SACD quality in and out of one then :-)

[terminator4]

@save2600
Let us know how you make out with your Sound Card, pls.

[platon42]

save2600 wrote:
Once again Chris - thank you for the tech specs here. Glad to know usbaudio.device has a 16-bit wordlength limit. No need to fuss trying to get 24-bit SACD quality in and out of one then :-)

Don't get this wrong. AHI supports sample bit depth of 16 and 32 bits and the usbaudio.class will automatically support up to 32 bit sample resolution, too (although I only had a soundcard to test with 20 bits instead of 16 bits). You usually will encounter different modes for every resolution the sound card provides. Of course, 17-24 bit will use 50% more USB bandwidth and 25-32 bit will use 100% more bandwidth than the standard 16 bit modes.

The sample resolution is independend of AHI's inability to provide a 32 bit sample frequency and thus is limited to frequencies between 1 and 65535 Hz.

Recording in AHI is limited to 16 bit stereo.

[save2600]

Okay... just brought home a shiny new Soundblaster X-fi USB soundcard. Plug and play on my Mac of course and sounds like a dream. Sigh... can't seem to get it to work on my Amiga :-(

Poseidon 4.2 correctly identifies this as a SB:X-Fi card with 4 options in AHI:

SB X-Fi Surround 5.1: 16bit Stereo++ (4bpf)
Ditto
SB X-Fi Surround 5.1: Hi-Fi 24-bit Stereo++ (6bpf)
Ditto

Great. But I cannot get AMPlifier to work with it. Have tried inputting all the right specs to no avail. In the configuration settings for AMPlifie under MPEG... I've tried both software and hardware decoding (and pointed it to usbaudio.device & paulaaudio.device). Nothing.

In Audio config, have selected X-Audio and pointed it to both .devices. Nothing. Changed Unit numbers. No change. Selected AHI too. Always comes up with the error:

'Couldn't open usbaudio.device unit X' or 'Couldn't open AHI device V4!'

What gives??

[Matt_H]

You don't access usbaudio.device or .class directly. Just configure AHI to use the new audiomodes and then tell your audio programs to use AHI unit x.

EDIT: So to clarify a bit more with AMPlifier, the software vs. hardware decoding configuration switches between decoding MP3s with mpega.library or a hardware device, like delinfampeg.device. As mentioned above, USB audio doesn't support hardware decoding, so leave that page alone (set it to software).

Ignore X-Audio as well. I'm not exactly sure what X-Audio is, but it seems like another retargetable audio standard that never caught on the way AHI did. Set that gadget to AHI unit x.

[save2600]

Eureka and thank you Matt,

The trick was changing the AHI preferences from Music Unit to Unit X - which in my case, I just put '0'. Now, the USB soundcard has awakened, but the song skips all over the place. Time to adjust some settings, huh? But as soon as I say that, the cheap-O_rip-off_phoney "16GB" flash I bought off ePay came up with an error that said it's a dead device (but it still works). LOL! Oh boy. So maybe I have a different problem now. lol

Update: Switched back to Paulaaudio and the music does NOT skip around. It only does that when piped through the SB card and cranking the buffers and prebuffering sliders all the way right DOES help - but only for a few seconds. I'm guessing the stoopid flash drive I was duped on is at fault? I say this because after 1/3 of the song... I get a lovely error in German that looks to say that UMSD flash drive has a checksum error. And then I get a requester that states my OS3.9 Flash drive (separate and hooked into the internal Deneb card) has a bad checksum too! Gosh... I'm about ready to grab a cold one here in a minute!

Is audio streamed via USB Flash and then piping it back out USB sound generally NOT a good idea?

[Matt_H]

Try playing the sample back from RAM:, a regular hard disk, or a different Flash disk. Maybe there's a problem running data in and out of USB simultaneously, but I think it's more likely your Flash disk is trash-worthy.

Also check the AHI prefs to make sure you're not using some overkill quality settings. 16bit, 44100Hz, 8 channels usually covers things for me.

[save2600]

Yep, it's the fact I'm streaming from USB back out to USB. Plays flawlessly when from RAM. I'm harddriveless on my A2500 right now, but I suspect there wouldn't be a problem that way either. Well, still... it's very cool the darn thing works and sounds pretty good in any event!

While not totally necessary, the equaliser still does not function. I was kinda hoping that would have been activated magically with this new hardware. lol