Caiman optical vs usb

[robyonekenoby]

Yesterday I made a A/B comparison between the two input with the help of my wife to avoid any subjective influence

Same song, Barbr Jung from Linn Records, 16/44

on the usb input I have a flac played by foobar
on the toslink input a burned CD played by an Onkyo DVD player

Well, I did expect to find the CD a loosy support, but it's a matter of fact, the CD sound (slighly) better; my wife and me agreed the most noticeably difference was surprisingly not on the highs, but on the bass definition

from the usb it was slightly blurred and rounded compared to the CD

Now I wanna try to play a WAV instead of a flac (I red somewhere it could make difference)

[StanleyB]

I have mentioned before that I find that FLAC is not as lossless as most people assume. I mentioned long time ago that a direct A/B test between a FLAC, WAV, and APE file shows that the FLAC file has less bass. Some people suggested it is the ripper/converter I used. I left that suggestion in the dustbin.

Glad to see you also discovered that FLAC has less bass. But it is not my DAC that is causing that. Try the same test between WAV on USB and WAV on TOSLINK. They are the same. It is only with FLAC files played through a DAC like mine with excellent bass definition that you can pick up the difference. On lesser DACs with poorer bass response you won't notice it.

[Tony Moore]

Hi,

If you take a WAV and convert it to FLAC, then convert the FLAC file back to WAV and do a bit-for-bit file comparison the two match. That's lossless. No information has been lost. You can re-create the original file. (Obviously here that's not looking at time-related information since the timing is handled by the replay mechanism)

Now, whether or not FLAC replay SOUNDS the same as WAV replay is another matter. That would be down to the processing that has to happen to decompress the FLAC file on the fly. In the case of the SqueezeBox I cannot tell the slightest difference between a FLAC and a WAV replayed at 44/16 so I'm happy with the implementation in the SB. I can't vouch for any windows based software though.

To me the fuzzy bass sounds like a higher degree of timing errors.

Tony

[robyonekenoby]

Yes Tony,

I was thinking about a timing problem, and I point out to computer generated jitter; the caiman has a synchronous USB input, and rely to the clock contained in the usb stream

That's why I have in order a better transport, an asynchronous USB to spdif converter, with a better clock, the musiland monitor 01 USD

This little toy allow me to play also 24/96 via usb :eyebrows:

[robyonekenoby]

Just tried same track: flac vs wav vs CD

Well, wav is better than flac, but CD player always win

More defined, more clarity, stronger (I mean not louder) bass

Hope the musiland will fill the gap

[magiccarpetride]

I have mentioned before that I find that FLAC is not as lossless as most people assume. I mentioned long time ago that a direct A/B test between a FLAC, WAV, and APE file shows that the FLAC file has less bass. Some people suggested it is the ripper/converter I used. I left that suggestion in the dustbin.

Glad to see you also discovered that FLAC has less bass. But it is not my DAC that is causing that. Try the same test between WAV on USB and WAV on TOSLINK. They are the same. It is only with FLAC files played through a DAC like mine with excellent bass definition that you can pick up the difference. On lesser DACs with poorer bass response you won't notice it.

I hear noticeable difference between FLAC and WAV/AIFF when played through my Touch into Caiman.

However, if I disable FLAC encoding on the Touch, and configure the Squeezebox server on my iMac to convert FLAC to PCM before sending it to the Touch, the differences disappear. In other words, FLAC sounds identical to the same track in WAV.

Conclusion? Always leave heavy lifting (i.e. transcoding from one format to another format) to the most powerful processing plant in your house. In this case, beefy iMac is the champ, while tiny Touch, with its tiny CPU and small main memory, should not be tasked with ANY heavy lifting.

[robyonekenoby]

Processing capability could be one of the reason, anyway I'm feeding the caiman usb with a notebook, CPU dual core 1.7 Ghz 2Gb RAM

Not exactly a poor processing capability, but WAV is still inferior to the CD player

Note the WAV and the burned CD have been created from the same flac I bought from Linn Records

Yes, the burned CD is superior to its own source file

So I tend to point out to jitter problem in the USB stream, probably the CD player (good quality Onkyo) has a better clock than usb interface

The musiland monitor receive data from USB asynchronously and recreate the s/pdif flow with its own internal clock generator, and from what I heard is a good quality clock

I will connect the caiman to the musiland toslink output, in this way I can also have galvanic insulation from the PC

[Clive]

Roberto, is the notebook running software set up to be so-called "bit perfect" such as ASIO4ALL or whatever you need for your OS and player?

There are so many variables with computers that jitter is highly likely for all sorts of reasons. However I sold my Meridian 588 because my PC sounded better that the CDP.

[robyonekenoby]

Hi Clive,

your statement is very encouraging

well, while I'm a pretty experienced diyer in audio electronics and working as a software engineer, I'm absolutely a newbie in computer audio :lol:

I'm starting right now after buying the caiman, and my idea is storing all my flacs in a PC; the main reason behind this is the capability to play the long awaited HD music in 24/96

Now there are many album available in this format, especially classical, so it's time to move

So, right now I've just installed foobar 2000 and disabled all the gain and equalizer options; do you mean I need something else to be sure the data streamed via USB is absolutely equal to the one coming from a CD player ?

[Clive]

Hi Roberto,

As you are using Foobar you are part way there already. It needs some help to avoid windows software which automatically re-samples / up-samples audio. For XP this is ASIO4ALL, for 7 it's WASAPI, There's loads to be found on this if you google it.

There's still potential for jitter so try different USB ports too, it they are spread around your notebook they may sound different due to their position and the wiring in between them. Some of the USB to SPDIF converters do a good job too, eg M2 Tech Hi-Face.

[robyonekenoby]

Thank you very much Clive, the magic word is ASIO

I digged in the net and find instructions to make foobar working with asio

I've installed ASIO4ALL, disabled the resample option and now the gap between USB and CD is closed!!!! :)

my notebook is running on win 7, so do you recommend WASAPI anyway?

Only issue, now it won't play 24/96 flac...

[Clive]

Hi Roberto, it'll just be a setting somewhere stopping you playing 24/96. I really don't know what but let me know when you find it! As for WASAPI, I'm an XP user so I don't know but check http://www.computeraudiophile.com/content/Windows-7-ASIO-vs-WASAPI and similar postings.

[WAD62]

Hi Roberto, it'll just be a setting somewhere stopping you playing 24/96. I really don't know what but let me know when you find it! As for WASAPI, I'm an XP user so I don't know but check http://www.computeraudiophile.com/content/Windows-7-ASIO-vs-WASAPI and similar postings.

...there is in winamp (allow 24 bit), so there must be an equivalent in foobar :scratch:

[Stratmangler]

...there is in winamp (allow 24 bit), so there must be an equivalent in foobar :scratch:

Look under File/Preferences/Output.

[WAD62]

I have never noticed any difference between FLAC & CD playback, that is probably because I'm using FLAC at standard 16/44.1, on networked SqueezeBoxes, and on my PC I use an M-Audio 2496 soundcard...so no USB connections...

[StanleyB]

There is a good discussion on Rock Grotto (http://rockgrotto.proboards.com/index.cgi?board=talk&action=display&thread=5839) about FLAC and jitter, which is worth reading.

[WAD62]

There is a good discussion on Rock Grotto (http://rockgrotto.proboards.com/index.cgi?board=talk&action=display&thread=5839) about FLAC and jitter, which is worth reading.

Interesting quote from the site..

"Convert it to FLAC using the highest quality setting"

...one assumes the author means 'highest compression', not 'highest quality' as FLAC is always lossless. ;)

This could as easily be seen as a test of ripping software, cd drives, etc, as there are conflicting results...too many variables!

There is most definitely a difference between a CD and a bad FLAC rip version of it, additionally the use of the highest compression levels is inadvisable as it can place too much load on playback for some devices. :)

[Clive]

OK, my turn for Foobar and ASIO4ALL help. I've been running 16/44.1 on XP with this s/w for ages. I'm now trying to play 24/96 but I'm having trouble with the config. I have 2 codecs available:

USB Audio CODEC - seems to max out at 16/48

RealTek HD Audio - has 8 channels, I configured the 1st 2 to L & R, the sound came out of the computer speaker, not DAC, and it was missing data (probably those other 6 channels).

Any advice on what to do next.....this must be a common thing to set up.

[Krisbee]

Clive,

As you've discovered the USB input on Stan's TC-7520 is limited to 16bit. So you'll have to use optical out from your PC to the DAC. Either it's inbuilt on the m/board or it means forking out for a 24/96Khz capable soundcard with digital out.

[Clive]

Clive,

As you've discovered the USB input on Stan's TC-7520 is limited to 16bit. So you'll have to use optical out from your PC to the DAC. Either it's inbuilt on the m/board or it means forking out for a 24/96Khz capable soundcard with digital out.
Chris, thanks.......I'd forgotten the spec.....it's all clear now. It was only one track anyway.

[WAD62]

OK, my turn for Foobar and ASIO4ALL help. I've been running 16/44.1 on XP with this s/w for ages. I'm now trying to play 24/96 but I'm having trouble with the config. I have 2 codecs available:

USB Audio CODEC - seems to max out at 16/48

RealTek HD Audio - has 8 channels, I configured the 1st 2 to L & R, the sound came out of the computer speaker, not DAC, and it was missing data (probably those other 6 channels).

Any advice on what to do next.....this must be a common thing to set up.

If you select RealTek HD Audio you're just sending it back to the onboard soundcard, and hence the computer speakers. :)

[robyonekenoby]

Clive,

As you've discovered the USB input on Stan's TC-7520 is limited to 16bit. So you'll have to use optical out from your PC to the DAC. Either it's inbuilt on the m/board or it means forking out for a 24/96Khz capable soundcard with digital out.

That's why I have in order the musiland monitor 01; with this little box I can skip the caiman usb limit, and depart from usb jitter issues

Right now, while waiting for delivery, when I want to listen HD tracks, I just enable the resampler embedded in foobar to downsample from 96 to 48; you can find under Playback/DSP in foobar preference

Well, after properly set foobar on wasapi output, I can say I have no more complains about flac quality, and some flac actually sounds LOT BETTER than the corresponding burned CD

I'm very very happy :cool:

[StanleyB]

I have been playing even 192KHz files via the PC and the USB output to the Caiman. I use Media Monkey and never had to do any sort of adjustment to get them to play.
I am surprised you have to do that in Foobar.

[Clive]

Hi Stan, I think what's happening with my Foobar on XP is that ASIO4ALL is detecting what the USB chip can do in the 7520 - it this likely?

I could down sample my 24/96 track but's it's just one track so I'm not really bothered.

[StanleyB]

Hi Stan, I think what's happening with my Foobar on XP is that ASIO4ALL is detecting what the USB chip can do in the 7520 - it this likely?
It's possible. I have been trying to get some specific info from Texas Instruments, but I get the feeling that I know a lot more about their chip than their their support team does.

[robyonekenoby]

Stan, reading at the specs for 2902, the maximum resolution accepted is 16/48

If you use foobar or any else player with no ASIO or WASAPI, windows automatically resample every data stream to the maximum allowed

Me too was able to play everything with no problem, but with ASIO or wasapi it's a different story

While they improve considerably the sound quality bypassing windows mixer and sending a bit perfect stream to the usb, they don't apply any automatic downsample if you try to play a track that exceed receiver capability, and simply give you a message error

[audionewbi]

any updates on the USB port development?

[nat8808]

Interesting quote from the site..

"Convert it to FLAC using the highest quality setting"

...one assumes the author means 'highest compression', not 'highest quality' as FLAC is always lossless. ;)

This could as easily be seen as a test of ripping software, cd drives, etc, as there are conflicting results...too many variables!

There is most definitely a difference between a CD and a bad FLAC rip version of it, additionally the use of the highest compression levels is inadvisable as it can place too much load on playback for some devices. :)

So if there can be problems with ripping to FLAC, why bother?

Storage space is so cheap as to just keep everything as WAV surely?

I mean, I find BT Vision boxes thrown away with now 320Gb drives in them.. put them in a cheap raid. Storage is virtually free.

[bobbasrah]

So if there can be problems with ripping to FLAC, why bother?

Storage space is so cheap as to just keep everything as WAV surely?

I mean, I find BT Vision boxes thrown away with now 320Gb drives in them.. put them in a cheap raid. Storage is virtually free.

It's all contextual Nat....
Flac is decoded by the player on the fly, so it is not the format which is the issue but hardware or software. It is not a widespread problem, in fact very limited, as you will find in previous threads.

Storage space is NO LONGER the issue it once was. Given you have no issues with playback of FLAC, why change back to WAV?

Once prices drop again for big SATAs, I will be able to hot swap the 2Tb backup instead of using the usb 1.5Tb. The extra storage needed for WAV may not be massive, but it all takes time to back up, especially on a stack of RAIDed 320s.

[Clive]

I don't backup, I copy new rips to 3 drives. No backup required. WAVs somehow seem better nowadays unless you wirelessly stream; just the same as doublespace is unnecessary nowadays.