Adding a global 48v switch to a console's power supply

[AnalogApples]

Hi! Can anyone walk me through adding a global phantom power switch to a Neotek power supply?

The reason I need a switch is because my channels are old and failing, so I'm frequently having to repatch things and I'm worried about hot-swapping. I wonder why they didn't add a switch at the factory. I'm worried that I cannot add a switch because maybe the supply needs a load? Yet it's safe to test the supply with it unconnected to the console. I'll be searching for a schematic of the later neotek models that DID have a global switch installed in the master channel.

 

[sweetbeats]

Questions:

Can you clarify what repatching you’re having to do related to phantom power? I don’t understand.

And you should never hot-swap or hot-plug stuff (modules or connections) on an analog mixer unless you know what you’re doing and know it’s safe. I wouldn’t hot-plug modules. So are you hot-plugging stuff and if so why?

Lastly does the power supply have a phantom power rail? Like are you saying phantom power is full-time on and applied to pins 2 & 3 of your mic inputs?

 

[Slouching Raymond]

If you flick the switch off, it may take some mins before the phantom dies away.

 

[AnalogApples]

Questions:

Can you clarify what repatching you’re having to do related to phantom power? I don’t understand.

And you should never hot-swap or hot-plug stuff (modules or connections) on an analog mixer unless you know what you’re doing and know it’s safe. I wouldn’t hot-plug modules. So are you hot-plugging stuff and if so why?

Lastly does the power supply have a phantom power rail? Like are you saying phantom power is full-time on and applied to pins 2 & 3 of your mic inputs?

I’ve got channels randomly dying and I want to take the TT cable from my mic lines and plug it into a new channel. Unfortunately I’d have to unplug the mic from the wall to do that, then move the TT cable, then plug the mic in. If phantom power was off globally (I never use it) I think I can do that without messing with the microphone cable. Right? Or is that still considered hot swapping? Yes there’s a seperate rail for the 48v. It’s very accessible. Even if I never needed to switch up the patch bay while the mixer is on, I still would prefer to turn off phantom. Phantom is applied globally to pins 2/3 of the mics. My understanding was that hot swapping is only a thing because of phantom. Further clarification, I’m not moving channel strips, in just patching a mic into a new channel which I cannot do while the mixer is on because my patch bay will short the phantom to the wrong pins as I insert the cable.

Since it’s apparently safe to turn on the power supply without connecting it to the console, for testing, shouldn’t it be safe to just unplug the 48v wire? It’s simply connected to a screw lug jack on the back.

 

[AnalogApples]

If you flick the switch off, it may take some mins before the phantom dies away.

I’d just leave it off all the time.

 

[sweetbeats]

I’ve got channels randomly dying and I want to take the TT cable from my mic lines and plug it into a new channel. Unfortunately I’d have to unplug the mic from the wall to do that, then move the TT cable, then plug the mic in. If phantom power was off globally (I never use it) I think I can do that without messing with the microphone cable. Right? Or is that still considered hot swapping? Yes there’s a seperate rail for the 48v. It’s very accessible. Even if I never needed to switch up the patch bay while the mixer is on, I still would prefer to turn off phantom. Phantom is applied globally to pins 2/3 of the mics. My understanding was that hot swapping is only a thing because of phantom. Further clarification, I’m not moving channel strips, in just patching a mic into a new channel which I cannot do while the mixer is on because my patch bay will short the phantom to the wrong pins as I insert the cable.

Since it’s apparently safe to turn on the power supply without connecting it to the console, for testing, shouldn’t it be safe to just unplug the 48v wire? It’s simply connected to a screw lug jack on the back.

Pic of the back of the supply, please.

And thanks for the clarifications.

You can hot-plug a mic cable to or from a phantom powered mic jack, but you don’t want to do that if you are using a ribbon mic, and you also have to mute the channel or your outputs because it will thump/pop really badly. Somebody correct me if I’m wrong on any of that. It’s just not a good idea, but it can be done.

I still would avoid having mic inputs on a patchbay especially when there is phantom powered in use.

Send a pic of the back of the supply. I think you are likely right about what you’re thinking of doing, but I want to visually verify.

 

[AnalogApples]

Pic of the back of the supply, please.

And thanks for the clarifications.

You can hot-plug a mic cable to or from a phantom powered mic jack, but you don’t want to do that if you are using a ribbon mic, and you also have to mute the channel or your outputs because it will thump/pop really badly. Somebody correct me if I’m wrong on any of that. It’s just not a good idea, but it can be done.

I still would avoid having mic inputs on a patchbay especially when there is phantom powered in use.

Send a pic of the back of the supply. I think you are likely right about what you’re thinking of doing, but I want to visually verify.

Here’s a pic of the supply. I can just unscrew the 48v before powering it on. Just worried it might need a load or the impedance gets too high and damages something. Google tells me I can do it though. Then there’s a pic of my factory patch bay. Mics come in on the top row, then the row under it is channel inputs. It’d be great to turn off phantom so I can move the mic TT’s to different channels while the console is powered on. I’ll mute the channels before plugging and unplugging.

If it’s ok to just unplug the 48v cable, I won’t bother with a switch. Thanks for your help, gentlemen!

 

[sweetbeats]

Lift that orange sumbitch.

You won’t damage the supply. The supply works when there is a load. No load, no work. It’s at idle. If you end up having new noise interference issues on your mic inputs (either RFI or hum), report back. There might be additional stuff to do. Like disconnecting the +48V conductor and its ground at the console frame. But if there’s no change/problem then there’s nothing else you need to do.

 

[AnalogApples]

Lift that orange sumbitch.

You won’t damage the supply. The supply works when there is a load. No load, no work. It’s at idle. If you end up having new noise interference issues on your mic inputs (either RFI or hum), report back. There might be additional stuff to do. Like disconnecting the +48V conductor and its ground at the console frame. But if there’s no change/problem then there’s nothing else you need to do.

Great! Thanks so much! I will lift that sumbitch, haha

 

[sweetbeats]

Zip tie the tail to the cable.

 

[AnalogApples]

Zip tie the tail to the cable.

(1 week later after I missed this post) “hey guys, heard a loud pop and a smelled smoke coming from my power supply and found my 48v rail welded to the 18v lug” Thanks for your thoughtfulness, Sweetbeats! I was going to secure it somehow.

 

[TalismanRich]

A little shrink wrap is helpful, and can be easily removed if needed.