Tweaker's Rash

[Sligolad]

I agree John and I would be happy to jump to I2S even if it meant having to sell off the Meitner or break in to it.
You sound like you are thinking along the same lines as Frederyk so it would be good to lock you two guys in a room for a month and see what comes out!!
RTE had a piece on the battery developments in Limerick this week, very interesting and hope they have their IP well put together, surprised there is not a lot more momentum behind this given its "potential" :-)

[jkeny]

I agree John and I would be happy to jump to I2S even if it meant having to sell off the Meitner or break in to it.
You sound like you are thinking along the same lines as Frederyk so it would be good to lock you two guys in a room for a month and see what comes out!!

Yea, I PMed him to notify him of this thread

RTE had a piece on the battery developments in Limerick this week, very interesting and hope they have their IP well put together, surprised there is not a lot more momentum behind this given its "potential" :-)

I don't believe that the media realise the significance of battery technology - it's just so easy to overlook - a bit like the mildly amusing scene in the "Graduate" where the Dustin Hoffman character is advised to get into "plastics" - it seems such a trivial thing to say!

BTW, this thread reminds me of that old joke about asking for directions & the answer "but I wouldn't start from here". I believe we have been starting from the wrong hardware place to get to our audio goal & it's only now that some of the ways forward are becoming clearer & easier to achieve, also.

[frd1996]

Hi,

Big thanks for John for dropping me a PM, otherwise I would completely have missed this thread.

Thanks for appreciation of the Linux PC. This is only a temporary thing. I am currently building dedicated audio computer based on Odroid X2 board: 4 ARM cores, 2GB RAM, USB, eMMC - almost as fast as my laptop. Initially it will be powered for a linear PSU (LT1083 will do), later batteries. At the moment I am at the stage of making Gentoo build for that platform.

For the player I will be using something I've been writing in a so called free time. It is pretty much the same idea as MQN but running in Linux environment, but I can bet the MQN is far more sophisticated than mine :)

I am progressing with both HW and SW, but this does not go as fast as I wished too. Other activities consume my time. And even if I manage to arrange some free time then I need to choose between one more hour of coding or building an amp/preamp/dac/whatever. I will be happy to show the you guys the Odroid X2 Gentoo build when it gets to more or less stable shape.

F

[jkeny]

Great to see you here, F
Your build sounds very interesting & look forward to hearing it. I'm sure that's also goes for a number of the forum members.

Do you have Gentoo working on the ODroid yet?
Have you tried your build with a standard audio player?

I know how that feeling of not enough time in the day!

[nige2000]

im excited to hear this new build too

i missed hearing your amps hope i get a chance to again

[frd1996]

Do you have Gentoo working on the ODroid yet?
Have you tried your build with a standard audio player?

I received the X2 board just before Christmas. I quickly tried Archlinux distro on the board just to see if it works (hardkernel - the odroid guys - have 1 month return policy if the board is faulty). Since then I slowly cross-compiled Gentoo for X2. As usual, initially I was doing it wrongly - it took some time to realize that. At the moment I have the base filesytem buill.tested with QEMU. Also the bootloader is there. At the moment I am configuring the kernel.

As for the standard audio player, I do not what "standard" means. The current Linux sound subsystem is called ALSA (http://alsa-project.org). It comes with two standard tools: 'aplay' and 'arecord'. They can play and record raw or wav files respectively. The typical soundcheck tools, you can call them. They are almost on in all linux distros I know. The X2 build has them as well.

Also, I was using 'aplay' with Meitner MA-1 dac (direct USB connection).

[jkeny]

Interesting, F
Can I ask why you chose Gentoo? I know Fran said that it is a tailored Linux that you only compile what you will need into the kernel but did you look at many of the other Linux kernels? There appears to be a vast range of kernels which are apparently optimised in different ways. For instance Linux micro-kernels seem to also be cut-down versions of the full OS & seem interesting. DaveF also mentioned real-time Linux (with some qualifiers) which seems interesting also. Linux for embedded devices also seem to be another segment worth looking into. I don't have an complete overview of what's out there now (even though I was around in '91 when Linux was born & noted it's unique approach). Interestingly the ARM processor was also born around this time & it's unique approach to running a computer with a reduced instruction set (RISC) also caught my attention. I didn't realise that >20 years later I would be looking into them again.

Anyway, I would appreciate hearing from anybody who knows more about the whole Linux landscape & the different categories of kernels that are now available.

The other thing that I think I mentioned in one of my disappeared posts was that I'm trying to look at this from both a hardware & software perspective. My initial premise is that by simplifying the hardware & reducing it's powering requirements so that we can better achieve a stable, rock solid, unwavering PS no matter what is being processed will greatly reduce the impact of the OS & software has on the output sound. How well this can be achieved remains to be seen & may ultimately require a dedicated MCU, FPGA or whatever?

[LowOrbit]

John

This scenario - lightweight Linux, direct I2S output - is very much here. I have basically removed my audio PC from my system as of a week ago.

Russ White of Twisted Pear Audio spurred me to buy a Raspberry Pi when he highlighted that you could a) get I2S directly off a header on the Pi and b) Raspbian now incorporated the requisite driver. There are at least two projects to deliver packaged music player Linux builds that can exploit this (and not just on RPi, Beaglebone and a couple of other arm boards) in a relatively painfree manner.

So, last week I loaded Volumio onto a RPI, hooked it up to the I2S interface on my Buffalo2 dac, and pressed play on the web-browser interface (I could also have used any one of the umpteen MPD clients available) on my Android phone.

For all the hard work people on this forum and others have done to improve the Windows audio experience, I will say goodbye to all that. There can be no going back.

Mark

[nige2000]

John

This scenario - lightweight Linux, direct I2S output - is very much here. I have basically removed my audio PC from my system as of a week ago.

Russ White of Twisted Pear Audio spurred me to buy a Raspberry Pi when he highlighted that you could a) get I2S directly off a header on the Pi and b) Raspbian now incorporated the requisite driver. There are at least two projects to deliver packaged music player Linux builds that can exploit this (and not just on RPi, Beaglebone and a couple of other arm boards) in a relatively painfree manner.

So, last week I loaded Volumio onto a RPI, hooked it up to the I2S interface on my Buffalo2 dac, and pressed play on the web-browser interface (I could also have used any one of the umpteen MPD clients available) on my Android phone.

For all the hard work people on this forum and others have done to improve the Windows audio experience, I will say goodbye to all that. There can be no going back.

Mark

intriguing
ill be surprised if i dont buy a board to test soon
so all i need is a RPI type board with i2s and a i2s compatible dac
i assume it will work with usb dacs too

makes much sense
http://volumio.org/raspberry-pi-i2s-dac-sounds-so-good/

[jkeny]

Yes, Mark that thread on Twisted Pear was one of the ones I was referring to.
Great to see you took the jump. Can you evaluate the sound quality compared to the Windows players you have been using here MQN/JLP?