[Henry_Killinger]

Quote:

Originally Posted by toughnut /img/forum/go_quote.gif Freeze? Clipping? May i know what cpu are u using? I have a Xeon quadcore 3.6ghz and a 600mhz celeron eeePC (downcloaked from 900mhz, using onboard soundcard). Both no freezing problem or encounter difficulties playing audio files. In case u didnt know, the software (winamp, foobar, etc) doesnt decode on the fly, it use buffering which meant process the required data earlier and store in on RAM. Running winamp on celeron doesnt even consume 3% of cpu processing power. Because i'm not using any soundcard or stuff like that. I'm suggesting usage of audiophile grade usb dac/amp which can be used together with normal dap. Moreover, those usb soundcard doesnt has enough amp to drive full can. Regarding those pcmcia card type, those are normally crap too. Regards

Um... first things first, the EEE does not use a celeron, it uses either a VIA or a Atom N270. Secondly, the for any USB to pull what you said off, you need the USB OTG architecture and this cannot be accomplished unless either one has the architecture necessary to run this.

It is roughly feasible to pull off what your speaking off. It will not look pretty at all. You can't just shove the goods into an old ipod case and expect it to work like that. I spent 10 hours the other day doing flow modeling in my electronics design class, and the final product still looks ugly as hell. Start off with a good Cirrus logic or wolfsom DAC, We used a CDB4265 Evaluation board in my audio signal processing class. Then, you use a couple audio codec chip and an audio processor. Then you need an ARM processor to delegate all the jobs on it.Then, a volume control module. Then you would put a small eeprom chip in and then you will have to program that with the instruction on what to do with the audio. This is all designed without power or portability in mind. The next step after doing this would be portability. You would then run in to problems with battery life and such. You would then have to make use of the low powered chips.

Like I said the idea is feasible but it is most definitely not practical. The idea is actually a pretty good idea for a senior design project, designing a feasible audiophile music player.
(experience:studying for my masters in Electrical engineering and my bachelors in computer engineering.)

 

[cbw]

Quote:

Originally Posted by Henry_Killinger /img/forum/go_quote.gif Um... first things first, the EEE does not use a celeron, it uses either a VIA or a Atom N270. Secondly, the for any USB to pull what you said off, you need the USB OTG architecture and this cannot be accomplished unless either one has the architecture necessary to run this........

That would be incorrect my friend, EEE PC's use either the Intel Celeron M ULV or Atom N270, Via was used in the HP 2133's i believe. Other than that you are right on.

 

[toughnut]

Quote:

Originally Posted by Henry_Killinger /img/forum/go_quote.gif Um... first things first, the EEE does not use a celeron, it uses either a VIA or a Atom N270. Secondly, the for any USB to pull what you said off, you need the USB OTG architecture and this cannot be accomplished unless either one has the architecture necessary to run this. (experience:studying for my masters in Electrical engineering and my bachelors in computer engineering.)

Asus didnt use Via cpu for their netbook. eeePC 701 and 900 use celeron while newer 901 onward use Atom. HP mininote use Via. I know cuz i use it

Why USB-OTG not feasible? Afaik, it only need the host to support it, which in this case, a netbook surely support it.

Experience (lol)
Bachelors in mechanical engineering and manufacturing, 15+yrs messing and destroying computer. I'm 23yr old though.

I'm still newb with computer internal working structure as i'm not interested with those stuff. I'm hardware guy and willing to learn

 

[Henry_Killinger]

Quote:

Originally Posted by toughnut /img/forum/go_quote.gif Asus didnt use Via cpu for their netbook. eeePC 701 and 900 use celeron while newer 901 onward use Atom. HP mininote use Via. I know cuz i use it Why USB-OTG not feasible? Afaik, it only need the host to support it, which in this case, a netbook surely support it.

I apologize, I stand corrected. USB-OTG architecture is not efficient for data transfer. If you directly connect a hard drive or some flash memory, the data transfer rate is much better, I don't have any strong numbers(I have them somewhere in my EE bible). USB-OTG is also in itself, a very wasteful architecture. USB-OTG uses more power than a disk/NAND controller.

Using a EEE pc to pipe out music through USB to a DAC is actually a pretty good setup. The problem is the DAC will require external power and if the DAC is bus-powered, that is another thing to draw power from the battery. This will drain the battery to between 1-2 hours. A portable hard, a interpreter, then a DAC combined with a good battery would last for between 4-5 hours. Another thing is a USB DAC uses a high quality DAC chip combined with a high quality USB bus interface chip. This is usually why a USB DAC costs a good bit. A Cirrus logic chip only costs between 9 to 20 dollars. An ARM runs from 40-60. A TI power management chip would also be useful, amongst other misc ICs. Some op amps and timer circuits would also be need. Given time and necessary motivation I could defintely come up with a schematic and a rough product list to make one, but I have neither.

Note:These numbers are from a DigiKey catalog

My brother is a mechanical engineer and my father is an instrumentation and automation engineer. I'm 3 years into an Dual-major here at Georgia Tech, spent more sleepless nights in lab walking from Klaus to Van leer doing lab. I've been soldering since I was five, I'm also pretty sure I have lead poisoning. I also have countless burns all over my fingers. I also smelt more chemicals doing copper leads on breadboards. (not bragging, just providing some backstory and some credence to my knowledge)

 

[toughnut]

Thanks for the informations (i hardly know what's those electronic stuff are about though haha).

Sorry for confusion, those OTG USB not required since it's a netbook. Afaik, old X5 have it and it's pretty broken function. Slow and suck battery. And yes, normally those DAC run on USB power and suck laptop battery. Ext 2.5in hdd with USB DAC/Amp running of eeePC probably wont last even 1hr. It's dependant on power outlet. So what i'm suggesting earlier is a transportable, not really a portable solution.

We need someone to build a diy modular but portable dap! 256gb ssd or 750gb 2.5in hdd, replacable audiochip, multiple choices audio i/o port, run on linux distro, fuel cell ready, etc packed into size of two stacked external hdd case

This will probably cost a car and size of a brick with current tech haha.


P.s: written on the soldering iron box as warning, AGE 8 AND ABOVE! J/k

 

[Henry_Killinger]

Lets see, we could definitely use a moderately sized case, 10in x 4in x 2-3in. Take a decent DAC and shove it in there, then take a lcd, an lcd controller and shove the rest of the stuff I said in there, and finally shove a 4-5 cell li-ion battery and that should give it a good life. then take a quality splitter and have one go to a spdif output and one that goes to a HP out. A replaceable chip though, is finicky especially cause you could use an ic socket and but you must make sure the sockets are the same, they could come in SIP, PSOP, SOIC, SSOP, any which way.
A good design would be, a SATA connector that goes into a drive controller, and then to a SSOP/SOIC/PSOP/SIP socket for the chip.

 

[Roo44]

Quote:

Originally Posted by qusp /img/forum/go_quote.gif do you have any clue what we're talking about here??

WOW love the passion mate, though the filo thing was a bit of a joke.


Quote:

Originally Posted by qusp /img/forum/go_quote.gif I think you misunderstand what audiophile quality means.

I do understand, and have spent a good deal of time with many Obsessive Compulsive Disorder types. Yes for some audiophile quality is a goal without completion, just a infinite process of incremental improvement; its about ameliorating the microscopic minutia, for others its the Audio equivalents of building a 4x4 Monster Truck, a way of showing off more money than brains, and then for other just the appreciation of better.

And I stand by the point of saying for all the portable amp procurements, imods investments, high end cable acquisitions there is a market for an Audiophile DAP (ADAP?) and likely it would be a product of an established DAP manufacture. (just as it is easier for Honda, Toyota, Nisson to establish a new luxury line in the US then it would for a new manufacture to create one)

But I do agree with you on the fact that there will be some OCD types who expostulate the inadequacy of this ADAP. Possibly me.

I think he is on to something:

http://www.head-fi.org/forums/f105/l...-silly-374155/

 

[Roo44]

For the nattering nabobs an interesting development:

http://www.head-fi.org/forums/f15/hi...ne-two-424091/

 

[buddhashenglong]

I thought iGod was an ipod with the bible in mp3 loaded on it.

 

[Papa Sun]

Here's my take on the subject:

First, I'd like a small, very simple DAP with no DAC and amp, just a player with some sort of simple but efficient UI, that plays all sorts of formats and outputs a nice bit-perfect digital stream through TosLink. Nothing else.

There are so many really nice DAC and AMP choices out there, but mucking about with the brick-sized iRiver H1x0 with it's stone-age UI, and the truly excellent but equally bulky D10 is not an option in the long run.

So, that gives me the idea of a modular kit of small boxes, attachable in fours, made up of
1) aforementioned DAP,
2) a simple DAC, with your choice of circuitry – Wolfson, Burr-Brown, Cirrus, Sigmatech, wha'eva'). (Maybe "rollable"? Is that at all possible with a DAC?)
3) a portable amp with rollable opamps, your choice of capacitors, etc., and
4) a Li-Ion battery pack.

Kind of like LEGO pieces, you assemble them after your personal taste. Custom ready-made arrangements with tailored opamp- and capacitor-setups, and the like. Which is what the HiFiMAN HM-801 is probably ment to be all about in the future, I suppose.

Apparently, tastes and opinions vary so much when it comes to sound, that trying to find the one "best" solution is a very elusive concept. Hence my modular likings.

Ah, the stuff dreams are made of...

 

[qusp]

Quote:

Originally Posted by Papa Sun /img/forum/go_quote.gif Here's my take on the subject: First, I'd like a small, very simple DAP with no DAC and amp, just a player with some sort of simple but efficient UI, that plays all sorts of formats and outputs a nice bit-perfect digital stream through TosLink. Nothing else. There are so many really nice DAC and AMP choices out there, but mucking about with the brick-sized iRiver H1x0 with it's stone-age UI, and the truly excellent but equally bulky D10 is not an option in the long run. So, that gives me the idea of a modular kit of small boxes, attachable in fours, made up of 1) aforementioned DAP, 2) a simple DAC, with your choice of circuitry – Wolfson, Burr-Brown, Cirrus, Sigmatech, wha'eva'). (Maybe "rollable"? Is that at all possible with a DAC?) 3) a portable amp with rollable opamps, your choice of capacitors, etc., and 4) a Li-Ion battery pack. Kind of like LEGO pieces, you assemble them after your personal taste. Custom ready-made arrangements with tailored opamp- and capacitor-setups, and the like. Which is what the HiFiMAN HM-801 is probably ment to be all about in the future, I suppose. Apparently, tastes and opinions vary so much when it comes to sound, that trying to find the one "best" solution is a very elusive concept. Hence my modular likings. Ah, the stuff dreams are made of...

LOLZ, actually there is only the D10 and D1 (and HMD) that can take advantage of your optical output while portable under their own power. your solution seems strange IMO; no dacs are not 'rollable' there is no standard pinout for them. the modular concept is interesting, but getting a group of niche developers to all make a device compatible with another niche platform will be a challenge in itself. very nice idea though.

one problem (sorry to be argumentative hehe) by separating all the components like you have, it will actually take up MORE SPACE not less as each device will need its own enclosure of sorts and an interface to enable them to talk to one-another instead of being hardwired.

battery life on the korg is easily lengthened with the included battery pack as well as the option to make your own (this one i'm doing) to extend life to closer to 15hrs. this PSU could also tp up my lisa, thats the idea and shrinks the size of my rig as it stands. i'm pretty bloody happy with th SQ of my rig/s, a little ighter is fine, but to be honest I dont mind so much, with the remote on iriver and the fact I always have a bag with me anyway.

 

[ezzieyguywuf]

I have only read the first few posts here, but the folks over at Rockbox are working on building a DAP from the ground up. Don't know how much progress they've made by now, but it is an open-source-esque project and from what I see they are pretty receptive to user-input. Maybe check that out OP

 

[Papa Sun]

Quote:

Originally Posted by qusp /img/forum/go_quote.gif LOLZ, actually there is only the D10 and D1 (and HMD) that can take advantage of your optical output while portable under their own power.

Correct, sir. As I'm using the D10 myself (and love it), I let others do the rest of the dreaming when it comes to other output formats.

Nevertheless, I believe there are excellent platforms for further development (gamma1, etc.).

Quote:

Originally Posted by qusp /img/forum/go_quote.gif your solution seems strange IMO; no dacs are not 'rollable' there is no standard pinout for them. the modular concept is interesting, but getting a group of niche developers to all make a device compatible with another niche platform will be a challenge in itself. very nice idea though. one problem (sorry to be argumentative hehe) by separating all the components like you have, it will actually take up MORE SPACE not less as each device will need its own enclosure of sorts and an interface to enable them to talk to one-another instead of being hardwired.

Very valid points there. A few minutes of research made me realise the DAC problem. Well, well... One could still have some sort of choice, by having several modules, each with a certain DAC setup, etc.

Your last point strikes me as the most comical aspect of my little rant – of course, I should have thought about that...

Considering the size of todays portable amps and (almost portable) miniature DACs, this would of course be utterly impractical. Unless one comes up with a genius new enclosure system, wich is sort of the whole idea.

I have no pretentions of this being an even remotely realistic project, at least not with todays components, enclosures, etc. But hey, it's a God, innit? ;]