[gates_2]

I don't have a laptop at the moment, but plan on picking up an EEE pc in the near future- the moddibility of these things is quite impressive. I'm looking to do an internal mod, and wanted to theoretically discuss a couple of options:

1. Internal USB dac *wonders if slightly modified alien dac would do the trick, though the board footprint is a bit large*

2. Internal USB dac + internal amp- the laptop spits out +9.5V from the battery, and thus I believe it could be possible to connect a tiny amp(simple as a cmoy, perhaps as complex as a low-footprint amp such as the PPAS). Considering the amp would draw somewhere between10-30 mA(at the low end) I don't think this would adversely affect the battery life THAT much.

If someone wanted a transport, it would seem to be possible to take an existing USB soundcard and strip it down to fit into the EEE, and then modify the unused modem port to serve as a coax connector.

Another option would be to rig a small volume pot in that same location.

Done properly, the comp could still retain its built in sound card functionality, for mic input, as well as driving the speakers when so desired, but have a dedicated line out to connect to an external amp, or, ideally, an internal amp to drive 'phones directly

Thoughts?

 

[n4k33n]

Who wants to mod mine =D

 

[Assorted]

That would be freaking awesome. Maybe a Pico can be stuck in there somewhere.

 

[gates_2]

what what i've seen a pico would fit no problem into the left side of the monitor

I think I was thinking more along the lines of a lower-budget, yet still great sounding, setup.

Are there any other small, usb powered DACs that sound pretty good?(besides the alien, of course)

 

[error401]

Most other USB DACs are going to be based on the same IC as the Alien - and the same supporting components.

If you were willing to compromise on quality you could get rid of the linear regulators on the Alien board and make it fully self-powered. If you did so with a compact layout it could probably be done on a board barely larger than the PCM2702 footprint. You'd probably have to have boards fabricated and build it yourself though - Alien is already pretty small.

I haven't seen inside the eee...how much room are we talking about here?

 

[hyjkim]

I just got an eeepc and I wouldn't mind modding it. I don't have extensive circuit board design experience so.. I probably won't be going that route. If I can get my hands on an alien I'll try my hand at it.

@error401, check this site out. EeeUser ASUS Eee PC EeePC Forum / EEE PC Internal Mods Guide
It has a bunch of pictures of the internals components of the eee

 

[uppis]

My guess about fitting the pico is not that positive, its about as thick (with chassis but still..) as the eee pc screen closed. Anyway it would be great if it could be done.

 

[error401]

I think if you build an Alien and mount all of it's electrolytic capacitors beside the board laying down, attached with wires you can probably fit it in. The 'lytic caps are going to make it too tall otherwise I would think.

 

[FallenAngel]

Well, there really doesn't look to be THAT much room in there. Maybe an AlienDAC will fit if you lay all of the caps down and make sure to pick a small value for the main PSU cap.

Hmm... come to think of it, an HPDac would be perfect for that application, it would probably fit, just pick proper caps for it.

 

[gates_2]

people have put complete GPS units with antennas, multiple flash cards, 2 usb hubs, FM tuners, and touchscreen units into one EEE, so i think we can fit one dac in- I agree that the Lytics will pose the biggest size problem- this would preclude the use of any botique, imho.. The alien dac with cheaper caps >>>>> stock onboard sound

 

[mixhamstermike]

did you pick up an eee then? are you still planning on doing this mod?

I have an 8G eee and am very interested in doing this and i have the same goals in mind: low cost, good sound

my first priority is integrating a headphone amp but I am not averse to the idea of adding a DAC (m-audio transit or building an aliendac)

but firstly the amp:

It looks like it would be possible to construct a cmoy to be small enough:

Sijosae's DIY *edit* just to be clear i am talking about the micro cmoy *edit*
Op-amp headphone amplifier - Instructables

they both raise the capacitors of the board so they lay flat. depending on the caps they should be flat enough.

ive spent quite alot of time on the eee modding forums and it seems there is some space (people have put flash drives on that spot) on all models right next to the audio ports.. so thats quite convenient

now that the size concern is cleared up the power supply has to be dealt with.

running of usb power is not really an option because it would require a low voltage op-amp plus ive heard usb power can add alot of noise to an amplifier.

the best solution would be to run it directly of the 7.4v battery of the eee. however i have never seen anyone use a 7.4v supply in an eee mod and do not really know whether this is possible. i have posted the question to the EeeUser ASUS Eee PC Forum / 7.4 volt point for headphone amp

the alternative would be to use two 3.7v cellphone batteries. this would ensure a good supply while placing no load on the laptop. two of the nokia bl-5c's would fit in the space under the ram bay door even in the 8g (the ssd is located there in the 8g but the space is even more free in the lower models). the bl-5c is cheap, cheap chargers can be bought for it and running a cmoy from two 3.7v batteries is not unheard of.

for now i will brush up on some soldering skills and build a standard cmoy and see if all this trouble is worth it for the sound.
maybe i will also build an aliendac and try this out aswell.

i will then try and hook the cmoy up to the laptop supply somehow (oh dear i can smell smoke already...) and if it works how this affects quality.

i am in the middle of exams at the moment so this is a long-term projection. it would be nice to hear your thoughts...

 

[mixhamstermike]

bump

 

[AudioNoob]

you can remove the fan to put the dac there

 

[mixhamstermike]

thanks for the tip. but then i risk overheating and sacrifice performance.

 

[129207]

Sorry for reviving this old thread but now that the Nuforce uDAC is around, would it be possible to integrate it in an EEE/netbook pc? I know the EEE pc has room inside for a DIY usb-hub so powering it wouldn't be a problem. Does anyone have pictures of the uDAC's insides?