Splitter Cable, splitting 1 condenser microphone output to two inputs for Apollo solo usb

geotungz

Member
Hi,

I would like to know if it is safe to split one condenser microphone output signal with a y cable to two separate xlr input lines on a UAD Apollo.

The purpose is to be able to try my dry signal with the unison built-in preamp, and my processed one with printed effects.

Will it damage my microphone or my apollo unit?

If it will not damage the mic or my unit, will it compromise the quality of the signal?
 

VomitHatSteve

Hat STYLE. Not contents.
I can't say for sure, but this sounds dubious.
A condenser mic require phantom power. So you'll either be providing power to the mic from both interfaces (which sounds bad for the the mic). Or only from one (which sounds bad for the signal)
 

geotungz

Member
I can't say for sure, but this sounds dubious.
A condenser mic require phantom power. So you'll either be providing power to the mic from both interfaces (which sounds bad for the the mic). Or only from one (which sounds bad for the signal)
I have two xlr inputs on my unit with pantom power on them
 

bouldersoundguy

<div><p>&nbsp;</p></div>
I do XLR splits for live recording. It generally works fine to provide phantom power from one input. The one time I had trouble was when a band brought a split for their IEM system and had phantom coming from their console. It caused an occasional pop from the rather old PA console. We just switched which console was providing it.
 

geotungz

Member
I do XLR splits for live recording. It generally works fine to provide phantom power from one input. The one time I had trouble was when a band brought a split for their IEM system and had phantom coming from their console. It caused an occasional pop from the rather old PA console. We just switched which console was providing it.
I will get enough power from power one input with 48v and leaving the other input without phantom power?
 

bouldersoundguy

<div><p>&nbsp;</p></div>
I will get enough power from power one input with 48v and leaving the other input without phantom power?
Sure. Splitting the output of the mic isn't going to make it need more power. It just needs one phantom power source to make the internal circuit operate.
 

Chili

Site Moderator
Those apollos are expensive, I wouldn't risk the chance. Record the vocal without the unison plug. Then in your DAW, copy the track so you have two copies, apply the unison plug to one track and your other processing to the 2nd track.
 

bouldersoundguy

<div><p>&nbsp;</p></div>
If it's phantom power on two channels of the same unit, it's all coming from the same source anyway. If it's on from both channels, there should be no current flow between channels.

But I'd just record the mic clean and add the effect later because that seems more practical.
 

geotungz

Member
Those apollos are expensive, I wouldn't risk the chance. Record the vocal without the unison plug. Then in your DAW, copy the track so you have two copies, apply the unison plug to one track and your other processing to the 2nd track.
Yeah, I thought of doing that, the issue is I have a solo, so my DSP is low. So I rather have at least one printed version with the clean one.

I figure with a preamp version and the clean signal, I can pick a different preamp or signal chain later on when I different plugins.
 

keith.rogers

Bobby'); DROP TABLE USER
They make a thing called a microphone splitter which creates a transformer isolated copy of the signal. The direct path is used to provide phantom power if needed. That is what should be used. I had a stack of them but sold them because I use an 8x splitter from Behringer. I would not use a Y-cable, personally.
 

bouldersoundguy

<div><p>&nbsp;</p></div>
Transformer splits were mostly for remote trucks that were on different power than stage. The transformers were there to stop ground loops. I've used straight splits on a number of occasions. One of my two 16-channel splitters has ground lifts per channel.
 

ecc83

Well-known member
If it's phantom power on two channels of the same unit, it's all coming from the same source anyway. If it's on from both channels, there should be no current flow between channels.

But I'd just record the mic clean and add the effect later because that seems more practical.
Absolutely, I see no danger to anything. There will be double the current available to the mic but it should only take what it requires. The mic will be working into half the mic pre amp's load impedance but again I can see no harm in that.

Dave.
 

rob aylestone

Well-known member
Never had issues with this - two mixers or pre-amps and one mic split to both of them. I have always turned on phantom on one and left it off on the other. The few occasions I double powered it I never noticed. The two 680 resistors current limit anyway - so when using VERY expensive equipment, it never worries me at all.
 

ecc83

Well-known member
Never had issues with this - two mixers or pre-amps and one mic split to both of them. I have always turned on phantom on one and left it off on the other. The few occasions I double powered it I never noticed. The
6k8 =6,8000 Ohms per 'leg' Rob. Typo I guess but you know I am a tekky, pedantic old bastable!

Dave.
two 680 resi6stors current limit anyway - so when using VERY expensive equipment, it never worries me at all.
 

rob aylestone

Well-known member
Have you noticed that when you complain about a typo, you always include one yourself? This is a rule! I missed a zero, and you added an extra one he he.

Seriously though - if a designer builds in phantom power, it's standard to also build in DC protection. In all the designs where phantom is a global feature the voltage is applied to every input - so adding a couple of capacitors is standard practice for isolation. I would be rather silly for designers to miss them out - although I remember one forgetting the voltage spec (Soundtracs in the 90s) and phantom power, one channel at a time killed the inputs, and mixers had to go back in for expensive cap replacement as it was such a common problem. The Sountracs Topaz 24 and 32 input desks - really nice mixers as it happened but that must have cost them a bit for the repairs.
 

ecc83

Well-known member
Have you noticed that when you complain about a typo, you always include one yourself? This is a rule! I missed a zero, and you added an extra one he he.

Seriously though - if a designer builds in phantom power, it's standard to also build in DC protection. In all the designs where phantom is a global feature the voltage is applied to every input - so adding a couple of capacitors is standard practice for isolation. I would be rather silly for designers to miss them out - although I remember one forgetting the voltage spec (Soundtracs in the 90s) and phantom power, one channel at a time killed the inputs, and mixers had to go back in for expensive cap replacement as it was such a common problem. The Sountracs Topaz 24 and 32 input desks - really nice mixers as it happened but that must have cost them a bit for the repairs.
Ah, a deliberate mistake there Rob but you spotted it (and I just saw a pig fly past!)

People DO get exercise about phantom power but as you say, it is now so ubiquitous that most gear should have some protection. There is a fashion now for "total DC coupling" Fine if you want to take the risk AND have all the VLF **** in creation eating up your headroom but don't whinge if the (very rare) accident with spook juice blows your op amps.

IMHO NO inputs should be DC coupled and for total protection the input caps should be non polar types (if an electrolytic is called for) and rated at 63V. These should be followed by an RF stop circuit and reversed biased diodes across the input chip. Thus protected 48V will likely do no harm.

Of course! Nobody ever buggered a valve with puny phantom power but they have many and several other disadvantages!

Dave.
 

Tadpui

Well-known member
There's a much easier way to record both a wet and a dry signal using the UAD routing/console software by using an aux bus, applying the FX only to the bus, then recording both the input (dry) and the aux (wet) in your DAW.

This video shows the technique nice and clearly:
 
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