Amplitude 5 free

[Simon Barden]

The Xenyx units are well known for underperforming on phantom power. The problem is not voltage but current, and not really meeting the standard requirements for phantom power current supply.

Capacitor mics all vary in their current requirements depending on the electronics they’ve got fitted, so there's no rule of thumb to say that x mixer will power a maximum of y capacitor mics. The more channels the mixer, the bigger the 48v current supply is, but with the cheaper analogue Behringer mixers, none of them are capable of supplying anything like full spec current on all the channels (the digital desks are probably better having had Midas involvement). Behringer are not alone in this, but they fall far shorter of the maximum current supply spec than almost anyone else, especially when more than one or two channels are used. I’ve seen several reports of one mic working fine but then nothing working when two were plugged in.

They are probably using the original DIN spec of 2mA max per channel, and many mixers don’t provide more than 1-2mA. The later IEC spec gives a maximum of 10mA, which is quite high as the most demanding mics rarely need more than 5mA. But a good mixer will provide that if necessary.

If a mic needs more current than the P48 provides, then it simply won’t work.

Very few budget mixer companies give a value for the maximum P48 supply current, and a lot of mics don’t have a current draw rating either (so you need to go looking for tech reviews where this has been measured).

[McCreed]

Good info Simon. Not an area I know a lot about.
Cheers

[McCreed]

I periodically took it apart to clean and lube, but evenually the slider track on the main volume wore out.

Interesting. It must have been an older unit, as my 802 (2011 or 12?) has all rotary pots no sliders.

Like this one: Xenyx 802

[king casey]

They come with a pathetically inadequate power supply.
A wall wart with cable each end.
There is a fragile 3 pin plug that eventually broke.
I went through 3 of them over the life of the mixer.

cheers, Mark.

[Simon Barden]

And 48v is the nominal unloaded voltage supply. The P48 spec calls for an unloaded 48v±4v at the terminals, so you can get between anywhere between 44v and 52v. The voltage at the mic, once the P48 is 'loaded' is normally a lot lower.

The power is supplied through a pair of 6.81k resistors per channel (which should ideally be matched to within <0.5% to get the best common mode noise rejection). The resistors limit the maximum current that can flow to ground (if the mic lead is shorted) to about 15mA to a) hopefully stop the short affecting other microphones and b) reduce the risk of excess current overheating components and risking possible component failure or even fire. Of course the main desk P48 supply has to be capable of supplying 15mA or over, otherwise the P48 power will still be maxed out.

But once current starts flowing through those resistors, you'll get a voltage drop across them, about 3.4v per mA draw (as the current is split across two resistors), so the voltage at the mic will always be lower than the nominal voltage, and can drop right down to 10v dc for a mic that draws the maximum allowable 10mA of current if the nominal voltage starts at 44v DC.

[dave.king1]

Great info Simon, my now unloved Behringer is a Xenyx Q502 purchased late November 2017.

From memory the "manual" that came with it suggested that it could have inadequate phantom power.

Condenser mics are Neewer NW700 & NW800 SDC and Behringer C3 LDC, definitely at the budget end but far superior definition for recording than the Sennheiser and Shure mics we have, I would love a nice Rode or Neumann or two but they are definitely not pensioner friendly.

Edited. to fix mic names & models

[Simon Barden]

Rodes aren't that expensive. A shame that they seem to only sell the latest NT1 as a package as it does make it quite expensive if you already have a decent mount and pop shield. The NT1-A can be had on its own, but is definitely a much brighter mic.

I have a reasonable collection of SDC and LDC mics. Some bought used, some bought new. My ears' HF is so shot now though that I really can't tell much of a difference between them. Certainly when looking at The Audio Test Kitchen web site, https://www.audiotestkitchen.com/ they all sound the same (unless the software was playing up and they were all the same sample!)

I have the Neewer NW-410 SDC pair set. Surprisingly good for the money. The omni and cardioid capsules are remarkable well matched (pretty much within 1dB of each other); the hypercardioid pair less so but still not bad. Not the quietest mics around, but as long as you are recording something with a decent volume they are certainly useable.