[Audiotodd]

What kind of source is feeding that DAC? It looks great but I'm curious as to how that lcd works.

 

[linuxworks]

they are not integrated or 'tightly coupled' in any way other than being in the same case

the lcd and IR are in the front and go to the arduino (cpu). it has an ethernet board on top of it. that ethernet goes to my house network switch where there is a linux box that is also reachable via IP. it has a webserver running and controls the mpd music player daemon. the daemon has a connection to the local (usb) sound card.

finally (grin) that usb sound card (which is a y1-lite usb-spdif converter) goes to the DAC's coax-in. the DAC sends out 2 rca line-outs (seen in the photo as a dangle wire and connectors) and that goes to a volume control box (not shown). that has a line-in and line-out and the line-out goes to my amp chain (b22 box).

it sounds more complicated than it is

next stage is to move that vol control box (its active element) into this big plastic box and run some SPI wires from the arduino (3 more wires from the alum box) to a vol control module and that will 'intercept' the line-out of the dac and give a 'new' line-out that is digitally vol controlled.

the logic and code are already in the arduino to do both ethernet-based music playback AND local SPI-bus based vol control using the PGA vol control chip.

 

[Baird GoW]

Quote:

Originally Posted by linuxworks /img/forum/go_quote.gif they are not integrated or 'tightly coupled' in any way other than being in the same case the lcd and IR are in the front and go to the arduino (cpu). it has an ethernet board on top of it. that ethernet goes to my house network switch where there is a linux box that is also reachable via IP. it has a webserver running and controls the mpd music player daemon. the daemon has a connection to the local (usb) sound card. finally (grin) that usb sound card (which is a y1-lite usb-spdif converter) goes to the DAC's coax-in. the DAC sends out 2 rca line-outs (seen in the photo as a dangle wire and connectors) and that goes to a volume control box (not shown). that has a line-in and line-out and the line-out goes to my amp chain (b22 box). it sounds more complicated than it is next stage is to move that vol control box (its active element) into this big plastic box and run some SPI wires from the arduino (3 more wires from the alum box) to a vol control module and that will 'intercept' the line-out of the dac and give a 'new' line-out that is digitally vol controlled. the logic and code are already in the arduino to do both ethernet-based music playback AND local SPI-bus based vol control using the PGA vol control chip.

WOW...

 

[diff_lock2]

Quote:

Originally Posted by onyu /img/forum/go_quote.gif I love your casing skills. Good to know someone else uses plastic boxes. Here is my aliendac in a plastic case that contained fish. [img][/i] [/td] [/tr] [/table] Once I find a better case, I will transplant the amp. The the plastic works just as well. I would like a wooden box, personal preference.

 

[32y0]

One of my first builds.
Not the most beautiful build, but it works for me.

 

[FallenAngel]

Looks pretty cool... now what is it?

 

[Llama16]

My guess is... a headphone amp
JK,

 

[Hayduke]

Quote:

Originally Posted by FallenAngel /img/forum/go_quote.gif Looks pretty cool... now what is it?

Exactly the thought that immediately came to my mind as well.

Quote:

Originally Posted by Llama16 /img/forum/go_quote.gif My guess is... a headphone amp JK,

lol

 

[smeggy]

Yeah, I wanna know too.

 

[motherone]

Quote:

Originally Posted by 32y0 /img/forum/go_quote.gif One of my first builds. Not the most beautiful build, but it works for me.

You will want to make sure you have an earth-ground on the chassis so nobody gets electrocuted if something goes wrong. I couldn't tell in the pictures if you have one on the IEC input, but just wanted to point it out if one isn't already there!

 

[32y0]

Quote:

Originally Posted by FallenAngel /img/forum/go_quote.gif Looks pretty cool... now what is it?

I started with this scematic of the amp, but the local audioshop didn't have the tubes. So we used EBC91 and PCC84 tubes, and they helped me to modifie the scematic.
So it's basically the amp from the link, but with some modifications.

Quote:

Originally Posted by motherone /img/forum/go_quote.gif You will want to make sure you have an earth-ground on the chassis so nobody gets electrocuted if something goes wrong. I couldn't tell in the pictures if you have one on the IEC input, but just wanted to point it out if one isn't already there!

It is allready there if I understand you correctly.

 

[rds]

In the picture it appears that nothing is connected to the IEC ground.

 

[motherone]

The Earth Ground is usually the center tab of the IEC connector (power input connector):

http://www.electronics2000.co.uk/ima...ta/iecdiag.gif

The earth ground needs to be tied to the chassis so that if there is stray high voltage, a person doesn't complete the path to ground and get electrocuted. Also, you should make sure that the power input is fused! Without one, you have a serious fire hazard. Unless the fuse is integrated into the IEC jack, I didn't see one in there, either.

Sorry if it seems nitpicky -- I don't want to rain on your project, but I do want to make sure if there's a fault, you and/or your house are still around to enjoy it!

 

[32y0]

Ah, now I get it.
Thanks for letting me know, I'll take a look at it.

 

[FallenAngel]

You might have misunderstond motherone, the center pin (ground) on the IEC power socket should be connected to the metal case. If something catastrophic happens (like a power wire getting loose or those capacitors touching the case, it will put full AC line voltage through the case (and anybody touching it). You seem you have connected the the signal ground to the chassis; this is OK, but would be better done through a ground-lop breaker (10R 5Watt wirewound resistor in parallel with 0.1uF / 250VAC capacitor).

A fuse in there will help as well.

EDIT: Wow, took me too long to post, most of it was answered above.