Display Power & Amplifier questions

[vast]

Hey fellas, got a couple of questions now I'm nearing the put together stage of my build.

I'm still a little unsure as to how to power my display  My design is based on Weecade and have the PSU for the PC at the back panel as per the original design.  Is it possible to tap some power from inside of the PSU?  By converting some molex adaptors maybe? 

My other question is around getting an amp sorted for the speakers.  I've heard conflicting reports about using a mini amp from eBay powered from the PSU with people saying that the HD can be heard during use.  I got a cheap set of USB speakers instead to cannibalize for the amp. 

I tried that tonight and I was very disappointed with the sound quality.  Obviously I'm not expecting audiophile sound from a tiny amp and some car speakers but it was really dirty sound and very quiet.

Any suggestions on either of my problems?  Is it worth trying a different set of USB speakers?  Or is there a mini amp that is going to give a clean hum free sound? 

[BobA]

You can connect the monitor to a 12V connector if that is what it runs on.  The mini amps work well on 12V but you have to make sure you have a common ground so no noise will be heard.

[vast]

I think I'm going to mount one of these in the back, with a connection from that to the monitor;



and get one of these for both the psu and monitor;



I was really hoping to get away with just the one connector on the rear.  unless i crack the psu and solder in a tap from the main inlet i don't think that will happen...

How do I go about getting a common ground for the mini amp?

[RandyT]

I think I'm going to mount one of these in the back, with a connection from that to the monitor;



...<snip>

I was really hoping to get away with just the one connector on the rear.  unless i crack the psu and solder in a tap from the main inlet i don't think that will happen...

Color me confused.  If you get one of those parts you showed, you can split the output to whatever you want to connect to your mains.  If it were me, I would strip the plug off of a power strip, and wire it to the connector you show here.  It has a fuse, so you just need to make sure that the part and fuse are rated for the total amount of current you plan to pull through it.

RandyT

[vast]

Well I have the cut out in the rear for the PSU as Lokesen's original plans.  I now need to power the display - to make it neater I was going to add the switched plug and wire in a power cable from the rear of it directly into the monitor.

Does this help;



This way I have 1 plug from the wall split into the 2 inputs on the rear.

[RandyT]

Does this help;

Quite a bit, actually.  By having the power supply flush in the back, you're pretty much committed to multiple power cords, or popping the PSU case and running a line to your monitor.  The only other option would be to put a cooling fan in the place you left open for the PSU, move the PSU inside the cabinet, and split off from the main power connector you were going to put in for the monitor.  Honestly, your cheapest and cleanest option will be to splice it in to the PSU.  Just make sure that you protect the wires well, where they exit the sheet metal case.  A proper sized rubber grommet is highly recommended.

[vast]

Thanks Randy, knowing that splicing into the PSU is a possibility is something that I was hoping someone would confirm  .  I'll do some research this eve before i decide what to do.

[BobA]

Just make sure that the ground to the amp is the same as your pc power supply.  In most cases connecting the metal cases will make sure their ground is common.  If your amp does not have a metal case the ground can usually be found where the speaker and input jacks are fastened.  My comment re the 12V plug assumed you needed DC power for your monitor and amp.  Sorry I did not realize you were talking AC,

[vast]

Cheers BobA, I ordered one of the small 12v amps tonight from deal extreme, it was super cheap.  obviously got a bit of a wait for it to arrive.

thanks for all the help so far guys, really feels like everything is slotting together nicely!

Hopefully i don't blow myself up after soldering in the line to the monitor! 

[vast]

Success!   

I soldered directly onto the input on the PSU and connected up the ground.  I the fed the cable out of the top of the PSU ending in a male IEC connector.

Click for large view - Uploaded with Skitch

Click for large view - Uploaded with Skitch

Looks nice and neat I think!

Thanks for all the help so far guys