IQAudio DAC - Reposition RCA sockets

[The Black Adder]

Hi all.

I have a new case to put the RPi/IQAudio Dac+ in. So I wondered if anyone tell me if it's possible to wire out from the IQAudio DAC+ board to offboard RCA sockets?

Here is the board... can anyone tell me if the mounted sockets can be removed? If so, can anyone fathom out which are the Positive and negatives?

Thanks
https://digitalmeans.co.uk/shop/image/cache/data/iqaudio/pidac-full_hd_audio_card-002-500x500.jpg

https://digitalmeans.co.uk/shop/image/cache/data/iqaudio/pidac-full_hd_audio_card-003-500x500.jpg

https://digitalmeans.co.uk/shop/image/cache/data/iqaudio/pidac-full_hd_audio_card-004-500x500.jpg

[struth]

Yup, desolder the 4 contacts and compress the lugs and they should in theory pop out. looks like its soldered on both sides so you will need to remove both sides. some braid might be best for topside. A meter will on ohms tell you which one is + re continuity check.

[The Black Adder]

Nice one, Grant... thanks :)

[Mark Grant]

A solder sucker will help with that and some old fashioned lead solder to help 'float' the modern lead free solder.

Cheap:
http://www.amazon.co.uk/Silverline-633609-Metal-Solder-Sucker/dp/B000LFTN4S

Quality:
https://www.adafruit.com/products/1597

FFS ;)
http://uk.rs-online.com/web/p/desoldering-guns-pumps/7553065/

Wow :)
http://uk.rs-online.com/web/p/desoldering-guns-pumps/8396135/

oxf0a9JKo7U
-

[struth]

A solder sucker will help with that and some old fashioned lead solder to help 'float' the modern lead free solder.

Cheap:
http://www.amazon.co.uk/Silverline-633609-Metal-Solder-Sucker/dp/B000LFTN4S

Quality:
https://www.adafruit.com/products/1597

FFS ;)
http://uk.rs-online.com/web/p/desoldering-guns-pumps/7553065/

Wow :)
http://uk.rs-online.com/web/p/desoldering-guns-pumps/8396135/

oxf0a9JKo7U
-

Needing to find some more lead solder myself. I am almost out of it. Cant abide that new stuff

[thommy]

Heavy metal poisoning is no joke. I'm currently on a 2 month nutrient supplement plan to save my liver from lead & mercury.

Have been using lead free solder for a couple of years and with an iron at about 375 degrees it flows very well. I didn't realise it was lead free until checking recently.

Those 4 contacts on the board the other side of the rca sockets are most likely the pair of positive & negative you're looking for. The two nearest the edge of the board are probably the positive but it doesn't really matter as it's an AC signal (unless you're using coax cable).

You can probably get away with just tagging 4 wires from those pins to your chassis sockets, no need to desolder anything or use any special tools.

[The Black Adder]

Hi Thommy.

Now that's great advice... many thanks :) I think I'll do that. So because it's an AC signal, it doesn't matter which is - or + ? I'm simply going to wire direct to sockets... or I may just wire the interconnects direct and use some glands on the casework, I'm pretty sorted when it comes to cables for this so it gives that option. If not, it will be directly connected to some outboard sockets.

[thommy]

In terms of running two thin wires twisted together to a panel mounted socket I would say it makes very little difference, except that BOTH of them need to be connected the same way. Take either the front or back contacts as positive and wire them to the centre pin of each rca socket on the chassis.

If you get them crossed over, the left signal will become out of phase with the right, just like if you swap the polarity of just one speaker cable.

[thommy]

I'm going to cover my ass here from any potential onslaught by saying this:

I do not recommend that polarity of audio signals be ignored. In a worst case scenario the two pins could be wired the wrong way round and run into coaxial cable, meaning that the positive goes down the outside of the cable picking up all the interference while the ground is protected from the noise it is meant to be picking up.

However from my experience even if that happened it would not necessarily be immediately obvious.

The way to be sure of which is positive without desoldering the pcbs sockets is to get a continuity meter and put one probe on the 3rd GPIO pin of the DAC, and try the two pairs of contacts with the other probe. The negative contacts will register a continuity with GPIO pin 3. The positivity pins are therefore the ones which do not register continuity, and should be wired to the centre pin of the chassis rca socket.

Coaxial cable is often used for audio signals, but the proper way to do it is do have a screened dual core cable, with one core connected to + and the other to -. The screen is then attached to the negative side of the source, pref. direct to the chassis. The other end of the screen at the receiver side is not connected to anything.

This type of floating shielding (at receiver end) is how audio cables can become directional.

[The Black Adder]

Thanks Thommy.

No probs... And thanks... :) I'll just do a continuity check on the outer of the plug to the solder spots on the underside of PCB and find it that way.. :)

[thommy]

Oh the simplicity, look like your Saturday's sorted then :)

[The Black Adder]

Hhaha.... yes, exciting day ahead! :eyebrows: - err! humm!