1394 Audio from a PC - The Beginning

Very interesting.

iLink audio player? ... I want it! ... and if it is any good, I will want it for sale in my catalog(s) online. Hopefully it will also work on the Mac ... as that's where the mainstream for FireWire audio is.

http://firewirestuff.com

Wow; a forum just for firewire, how could I have missed this before?

I've been hoping for some time to use a PC as a media server, and have it connected to an AV amp by iLink. There didn't seem to be any way to do it, appart from one or two comercial developments like orangeware that weren't interested in domestic applications. I'd liketo pursue this, though.

Thanks for the tip, Krobar. How have you been getting on with i-Link? Did you have a player with iLink? How do you find the audio quality? That's my real motivation.

Nick

I firmly believe that 24bit / 96K or better audio is the only way to obtain decent bandwidth and quality reproduction and playback. Most music professionals and recording engineers who know the difference agree.

USB claims 24bit/96K, but no more and not without a whole lot of jitter and latency questions.

Ethernet (as the music pro equipment makers impliment it) just can't swing the bandwidth without a lot of handshaking grief like jitter, etc. = for back up only.

The SPDIF / TOSLink optical to DAC does work beyond 24bit/96K bandwidth, but this is usually accompanied with FireWire DAC and ADC anyway, so ...

FireWire does get the job done handsomely. Up to 8 channels at 24bit /48k per channel and easily up to 4 channels at 24bit/96K per channel. This makes passing all the various multichannel audio scenarios possible, Dolby 5. thru 7., THX or whatever ... or 4, 6 or 8 full bandwidth discrete channels, in either direction, record or playback, rip or roar.
...
FireWire audio hardware samplings for less than a US$600:
http://www.m-audio.com/products/en_u...e410-main.html (note both SPDIF digital and FW DAC/ADC / 4 channels)
http://rolandus.com/products/product...1&ParentId=114 (note both SPDIF digital and FW DAC/ADC / 6 channels)
http://www.echoaudio.com/Products/Fi...ire4/index.php (note both SPDIF digital and FW DAC/ADC / 4 channels)
http://www.tascam.com/details;9,14,45,16.html (note both SPDIF digital, MIDI and FW DAC/ADC / 8 channels @ 24bit/96K combined)

Reviews needed for and by audiophiles ...

Mercenary announcement: FireWire evangelist on board = http://firewirestuff.com = me

Well, no, 96 kHz is considered overkill by many too. Best estimates are that any conceivable audio issues with 44.1 kHz sampling -- and the audibility of these is questionable in a well-designed, oversampling system -- goes away by the time you get to around 60 kHz. Though with storage and processing power being relatively cheap these days, 96 kHz is more a 'why not' issue than a problem. 192 kHz is absurd.


24 bits during production/processing is de rigeur if your delivery format will be 16-bit, but the inherent need for 24-bit at the playback end is also dubious, given that 16 bit already delivers > 90 dB of dynamic range, which is more than the range available in many recordings, and many home theaters.



But HDMI can do that too, yes?

" ... Some TOSLink implementations can do 24/192 stereo, it is the 24/96 and 24/192 5.1 that is of real interest with Firewire (Driver does not support this... yet). ..."

" ... 96 kHz is considered overkill by many too. Best estimates are that any conceivable audio issues with 44.1 kHz sampling ..."

The above is a rather mixed message.

IMOP:
* FireWire is capable of multichannel 24bit / 96K or better.
* All decent professional studio work is done on a minimum of 24bit / 96K equipment or converted from analog to 24 bit / 96K digital as an intermediary to production ... so the good stuff is 24bit / 96K.
* Even my old ears can hear the difference between 24 bit and 16 bit playback.
* Even my tired old ears can usually tell the difference between 44.1K and 48K or higher sampling rates. "CDs suck" - Bob Dylan in Rolling Stone magazine interview of this year.

" ... When it is necessary to capture audio covering the entire 18-20,000 Hz range of human hearing, such as when recording music or many types of acoustic events, audio waveforms are typically sampled at 44.1 kHz (CD) or 48 kHz (professional audio). ... Even a casual glance at professional audio magazines (e.g. Sound on Sound) will reveal an industry trend towards sampling rates well beyond the basic requirements; 96 kHz and even 192 kHz are available. ..." From: http://en.wikipedia.org/wiki/Samplin..._processing%29

Yes I can tell the difference !! You can too !! Get a copy of a really good DVD-A disc and compare it tothe CD version. Listen to it on your DVD player patched through your stereo as best as you can = best quality playback possible.

Most modern DVD players will play both DVD-A and CD music ... some have SPDIF / TOSLink outputs ... some have good DAC analog outputs. (A good one: http://oppodigital.com/dv981hd/dv981hd_index.html = plays everything, even Euro zone 2 video with a tweak!)

24bit verses 16bit / Bench Marks for quality comparisons of DVD verses CD:
http://www.classicrecords.com/item.cfm?item=HDAD%202008 * verses * http://www.amazon.com/Folk-Singer-Mu...dp/B00000JNOJ/
http://www.amazon.com/Love-CD-%2B-Au...dp/B000JJS8TM/ * CD + DVD-A set contains both!
http://www.amazon.com/Bonnie-Raitt-F...dp/B000GGSLV8/ * CD + DVD-A set contains both!
http://www.amazon.com/Musicares-Pers...dp/B000GH3QFI/ * verses * http://www.amazon.com/gp/product/B00007IT8S
... There are countless more examples. I don't buy CDs any more, just DVD videos and DVD-A and SACD discs.

So how do you get this better quality outta your computer and into your speakers? My suggestions are FireWire or SPDIF (TOSLink optical if possible, otherwise coaxial). USB just can't quite make it. PC plug in cards (except for TOSLink optical) let too much PC power supply noise through. You don't really know exactly what Internet radio feeds can sound like until you play a 96K feed through a FireWire connected DAC to a decent system.

" ... But HDMI can do that too, yes? ..." Yes!! it can, but most TVs just don't have decent built in speakers. Some HDMI TVs do have "quality" outputs, but I have not found any TVs with an HDMI to DAC capable of 24 bit, 48K or better.

My current system: Apple MacBook laptop through M-Audio.com FireWire Audiophile through Bottlehead tube pre-amp (!) through DIY stereo power amp through http://www.magnepan.com/model_MMG mains and DIY sub woofer (video output laptop direct DVI to HDMI to Samsung LCD flat screen) ... Captial G dam man its gooood ...

In well-set-up blind tests, I think it's unlikely most people, including you, could tell 44 from 48 (much less 96 from 192!), or 16 from 24. (And where one CAN tell the higher SR from 44.1, it's almost certainly due to implemenation issues like filters...not due to someone actually hearing the extra 2 kHz above 22 kHz). Using 24 bits for *production* has a very sound technical basis: avoiding introducing audible errors upon conversion to 16-bit. But for the final product to be played at home, 24 bits of available dynamic range are overkill. But like 96 kHz, it's provided because it CAN be, not 'cos there's any pressing need for it. People tend to reflexively think higher numbers must mean better sound; the industry is happy to hype that, though 'hi rez' discs didn't seem to catch on they way they;'d hoped.

Bob Dylan was referring to excessive dynamic range compression, which has been common since the mid-90s on CDs -- not to supposed sampling rate deficiencies.

The 'industry trends' are not necessarily based on any scientific discoveries or data ; that;s the problem with 'industry trends', according to guys like DAC designer Dan Lavry.

The fact that you can buy 'hi rez' discs means nothing, as far as proving that 'hi rez' is audible...you can buy all kinds of audio snake oil, if you wish to. I own several dozen SACDs/DVD-A, all in the hopes of getting interesting *surround mixes* as well as the possibility of better remastering than previous CDs. Because these are always remasters, so you're not just comparing formats, you're comparing source tapes, EQ moves, noise reduction etc. You cannot use a comparison of two different remasters, to make claims about a format, unless you're dead sure that everything is the same except for the format.


I run HDMI from one of my DVD player to my AVR; the AVR catches the multichannel digital audio stream (including DVD-A and SACD) and passes on any video stream to my TV/projector. That's how most home theaters work. So your point about TVs not having decent speakers doesn't seem germane to me. I've also run ilink from a different DVD player, to the same AVR. Obviously, there, I have to run the video via a separate connection. So at this point in time the advantage of ilink is unclear to me.

But, while it is possible (with some work) to pass DVD-Audio via PC, I don't know of any disc drives that can read SACD.

Don't know whether the newer DTS/Dolby Digital hi rez audio formats can be passed via PC. Are there disc drives that play Blu-Ray/HD DVDs ?

" ... In well-set-up blind tests, I think it's unlikely most people, including you, could tell 44 from 48 (much less 96 from 192!), or 16 from 24. ..."

Go ahead and set one up for your self ... Its easy: get your DVD player plugged into your stereo through a true 24 bit pathway ... most modern computers are capable of the playback part, the 24bit interface may be a little higher degree of difficulty ... Then play any of those DVD-A v. CD albums that you have access to ... (I listed several really great comparison disc sets above) ...

Even I, with tired 63 year old ears, can tell the difference between the DVD-A or DVD-Video (a movie sound track works as well = usually 24bit/48k) when compared to "ordinary CDs ...

" ... Bob Dylan was referring to excessive dynamic range compression, which has been common since the mid-90s on CDs -- not to supposed sampling rate deficiencies. ... "

Bob Dylan was refering specifically to his latest album, "Modern Times", which sounded so much better in the studio (@24bit/192k) than it did as produced (by Sony) for mass consumption in CD format = "CDs suck" ... He has since had several things to say about the superior quality of the soon to be released vinyl LP and the soon to be released DVD-A version (ala EMI) in Europe (without, as you point out, the excessive compression)

Krobar: " ... ILink [aka FireWire or IEEE1394a] has the following advantages over the current HDMI 1.3 devices: ... Rate Control - 0 Jitter between source and amp ... Daisychaining ... Autoswitching ... "

Yes indeedy although latency is about the same and also that virtually all public releases of HDMI are single directional, source to display, where as iLink (FireWire / 1394a) is totally bi-directional = read or write, pull or push, record or playback, rip or roar and as you note peer to peer daisy chaining or star topography.

" ... A $20 PC card will be capable of sending 24/192 5.1 as soon as software is ready. ..."

The software for iLink or FireWIre for the above activities is readily available for multichannel record and playback at even higher rates than 24bit / 192k (ex: http://www.digitalaudio.dk/ax24.htm ) ... It is called variously "Pro Tools", "CakeWalk" or "GarageBand" or any of a dozen other trade names for pro and semi-pro record and playback software that recognizes IEEE1394 hardware ports. (The software you refer to is for original generation of Dolby 5.1 or THX or whatever "surround sound" blows up your skirts.)

As for the question of "to SPDIF or not to SPDIF", rethink those links above as each and every one of those FireWIre (totally iLink compatible) devices mentioned has a built in DAC with multi channel analog output as well as the digital and works with 24bit/96k as a minimum, some at 24bit/192k too.

" ... HDMI 1.3A optionally offers rate control but no source devices exist yet. Revision 6 of HDMI has finally caught up! ..."

I knew about HDMI v. 1.4, the newer Apple scenario with only very modest changes to audio reproduction ... ... Oh, well ... "there is always a faster gun ..."

krabapple: " ... So your point about TVs not having decent speakers doesn't seem germane to me. I've also run ilink from a different DVD player, to the same AVR. ..."

Good for you!! You obviously have gone to the trouble to research the plithora of built in audio and supplimental speakers for such ... I have to deal with my medium scale Samsung TV/display, which has terrible built in speakers and I can't recommend the built in HDMI to DAC as viable, 'cause the power supply stinks resulting in medioker audio at best. (My current system: Apple MacBook laptop through M-Audio.com FireWire Audiophile (24bit/96k stereo) through Bottlehead tube pre-amp (!) through DIY stereo power amp through http://www.magnepan.com/model_MMG mains and DIY sub woofer (video output laptop direct DVI to HDMI to Samsung LCD flat screen) ... Captial G dam man its gooood ... )

" ... Whats the point in spending $500+ when a $20 firewire card can yield better sound quality? ..."

Not too much point unless you are talking about actual 24bit / 96k or 192k DAC outta that US$20 card ... I have never seen a 20 buck card that could do this ... in either direction, record or playback.

I may be an old dog, but I can learn this new trick: And if there is a $20 PCI card that will do this: convert digital to good quality analog audio or the reverse, I want one!! And I don't care if I have to write the drivers myself ... Got a link to this inexpensive card?

(I already have several variations on US$29 FireWire, 1394a, iLink compatible PCI cards, but none of them will convert a FireWire protocol audio data packet stream into analog audio at any bandwidth. This: http://www.ambisonic.net/dvd1394.html is fine information about and for digital to digital data streams (iLink <> SPDIF), but when used in conjunction with an "ordinary" FireWire / iLink PCI card, the data stream still needs to be converted to analog to make the speaker cones wiggle at some point ... thus I stand by my links to those (and many other) semi pro and pro level FireWire / iLink / 1394a Digital to Analog (and analog to digital) Converters. Are these that expensive? Well I would rather have high quality, 24bit/96K stereo conversion than, say, another iPod ... )

But first, are you sure the DVD-A and CD were mastered the same, except for format?



But that's also different mastering, for pete's sake!

Quote/link, please? I dont' recall DYlan saying that 'CDs suck' generally, nor that the problem is insufficient sample rate or bit depth.



Links? (The vinyl certainly won't have an effective 'sample rate' of anything near 192 kHz -- that is, offering a flat frequency range of 20-96 kHz -- nor a dynamic range equivalent to 24 bits!)

What on earth are you talking about??

I run an ilink cable from my Yamaha S2500 DVD/SACD/DVD-A player, to my Pioneer 74txvi AVR, which is connected to a set of matched loudspeakers and a sub. No 'supplemental speakers' are required for ilink per se, only for surround sound sources generally. If I want to pass video from the Yamaha, I have to add another cable.

For video I use an Oppo DVD player with HDMI output, to the AVR, and then another HDMI cable to my projector. The audio stops at the AVR and goes to the loudspeakers, the video is passthrough. (Actually the Oppo has all but replaced the Yamaha, since it too can play all audio formats, and pass audio AND video via that single HDMI cable.)