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Ofcourse, everything in the computer is a packet. Smallest packet is a word. Smallest word is a byte. Then there are OS protocol packets which are a combination of several bits which encapsulate data bytes.

Checkout RTOS on wiki. I has some good info.

What does RTOS have to do with Windows or Linux or USB? USB is not intended to be a real-time synchronous interface. I suspect that the reason many people prefer the USB interface to SPDIF or other synchronous interfaces is because it sends bulk data in packets before it's actually needed so the DAC runs entirely on its own clock and always has the data available when it needs it.

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USB does not exist in vacuum. USB does not send or receive any data. OS manages the USB. OS uses the USB for data communications.

Anyway, if you want to discuss further lets take it offline.

I'd love to hear it but it's a long drive to Oregon. I'll take a look at mpd.conf. In V3 apparently there was a default setting for Cantata. I'm not seeing that in this version. Mpd.conf looks a little sparse right now, with a lot of missing instructions. If you get a minute, could send a screen shot of your mpd.conf? Maybe I've misconfigured mine. I also cannot get my network to see the machine with AP-Linux. Have you solved that?

It's certainly very different from Snakeoil. I don't mind tinkering with it a bit.

There are settings within Foobar2000 that optimize if for PC use as well. Lots of controls many do not take advantage of.

Also an async USB DAC interface does the data transfer timing with it's internal clock, not the PC clock.

Didnt know you moved.

I am using wired network, it configured itself as DHCP without any issues. From AP-L Instructions:


Using the default MPD config as of now. Only change I made are the the Music Directory and USB Destination. I will send it tonight.

That reminds me, last night I was listening Sinatra. Observed his voice sounded more natural, more intimate. The mid-range bloating and huskiness in the voice were reduced. I think I like it, but need a lot more listening to be sure. I will try out format 32 instruction.

True, but that comes into picture only after the CPU and OS allocated time slot of the music server process, and and the music server tries to send a small chunk of data to the DAC. I do not know the size of streaming chunks used in ASIO. This is the issue I am trying to emphasize. NO matter how fast the USB is, CPU/OS and other processes running in the system will mess up the timing of the data stream.

For example if I am playing a 300MB DSD128 file which lasts 6 minutes, it could be sent to DAC is thousands of small data streams.

Further more, there should not be any other device on the USB for the controller to respond immediately (key word "serial"). If a mouse, keyboard, hard disk are working on the USB bus, the USB controller will accommodate each device by allocating the time slices.

That is why jPlay takes over the entire server disabling all unnecessary processes and keyboard, mouse etc when playing the music to dedicate max possible resources to itself.

Ah, forgot a step, thanks. I'll do that. You've certainly got me interested in working with it. I can hear the advantages, it's just too "etched" right now.

I was happy to take this off-line, but...

I don't think you understand how audio data get transferred from the PC to the DAC. As you said, the data is sent in chunks, or packets. Enough is sent in each chunk to fill the DAC's buffer and keep the DAC busy until the next chunk is sent. Since audio streams are given a high priority in an OS since audio is one of those things that has to be serviced in a timely manner or it doesn't work well, regardless of what the PC is doing otherwise it will service the audio stream. Of course there can be exceptions, but you would hear the audio drop out if there were instances where there was no data available for the DAC to convert to audio.

Audio is slow to a computer, even a low powered PC should have no problem keeping up with anything audio. Keyboard and mouse inputs are even slower, and lower priority, and will not have any effect on audio. I'm using a Core 2 duo PC in my main system. Audio is stored on another PC in the house. I control the music PC using remote desktop. This fairly low powered computer manages to fetch the music over the LAN and feed it to the USB port or sound card and at the same time provide the remote desktop host to my laptop while I move the mouse around with no issues at all.

The fact that jPlay locks up the computer while something is playing is a non-starter for me. You can't pause or stop something playing? I control the volume through the PC, it's an external analog volume control. With jPlay I would not be able to adjust the volume while something is playing?

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I want to apologize, you do understand how it works.

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I have too much stuff - https://www.pleasebuymystuff.com