---AD-20 > recorder
/
Mics < splitter
\
---V3 w/phantom > recorder
I've also done a split with phantom on both. However you do it, keep in mind that level changes on one unit may affect levels on the other.
I've also done a split with phantom on both. However you do it, keep in mind that level changes on one unit may affect levels on the other.
Yah - that sounds like great advice... ???
the idea is that phantom power can potentially color the sound of the pre and if you're doing a comp where one or both of the units does not have it's phantom on you are not really getting a true comparison of what both units sound like under actual show conditions.
the idea is that phantom power can potentially color the sound of the pre and if you're doing a comp where one or both of the units does not have it's phantom on you are not really getting a true comparison of what both units sound like under actual show conditions.
Wrong...
I've also done a split with phantom on both. However you do it, keep in mind that level changes on one unit may affect levels on the other.
Yah - that sounds like great advice... ???
what's the problem? what he said is absolutely true
the idea is that phantom power can potentially color the sound of the pre and if you're doing a comp where one or both of the units does not have it's phantom on you are not really getting a true comparison of what both units sound like under actual show conditions.
Wrong...
-t fuckhead for not backing your comment w/ some actual info.
Dual phantom in this manner is safe. The way the mics are set up with an XLR splitter, the phantom power is being applied in parallel. In parallel, the current load is divided among the two power sources (the ratio of which depends on the impedence of the mic inputs) and the voltage remains constant.Wow, great job of explaining it.
As for the level fluctuations, I learned that from experience (Derek Trucks show with Scott Brown where we split his 4022s to a V3 and ULN-2). I have the idea that changing the gain on the preamp slightly affects the impedence of the inputs which causes the balance of current to shift. Since we're talking small amounts of current and resistance, that would explain the slight effect on levels. If one of the more EE-minded folk here could confirm this or correct my theory, that'd be cool of you.
Go ahead pal - use 2 phantom sources...
The whole idea is so fucked - I dont even want to try...
Dual phantom in this manner is safe. The way the mics are set up with an XLR splitter, the phantom power is being applied in parallel. In parallel, the current load is divided among the two power sources (the ratio of which depends on the impedence of the mic inputs) and the voltage remains constant.
As for the level fluctuations, I learned that from experience (Derek Trucks show with Scott Brown where we split his 4022s to a V3 and ULN-2). I have the idea that changing the gain on the preamp slightly affects the impedence of the inputs which causes the balance of current to shift. Since we're talking small amounts of current and resistance, that would explain the slight effect on levels. If one of the more EE-minded folk here could confirm this or correct my theory, that'd be cool of you.
Go ahead pal - use 2 phantom sources...
The whole idea is so fucked - I dont even want to try...
Do you know anything about electric circuits when you say this?
By using a splitter to split the electrical signal to the mics, you create a parallel circuit. In a parallel circuit, the voltage on each side of the circuit remains the same and the current varies. Thus, applying +48v phantom power to both sides of the parallel circuit is not problematic in the least bit. The available current increases (since both the V3 and the PS2 are supplying 48v phantom), but the mics will draw what current is necessary, so the additional available current isn't a problem at all. (In fact, it could be a benefit if you needed to power current hungry mics like Earthworks.) Both the V3 and the AD20 are expecting +48v phantom at their inputs, so they use DC blocking capacitors to block the DC phantom voltage and allow the AC mic signal to pass. This is exactly how phantom power is designed to work. So to reiterate, it isn't a problem at all to have phantom on from two sources. No different at all really from wiring up two batteries in parallel to increase your runtime from using one battery.
It'll depend somewhat on the circuit design, but changing your levels on your preamp will change the impedence of the circuit. This slight change in impedence isn't a problem either, but it will slightly change the mic signal levels the other preamp is seeing, thus the impact of changing levels on one unit on the other. Not a problem, just inherent to using the mic splitter cables. You could solve this by using a transformer based mic splitter. In fact, if you used a transformer based mic splitter, you would absolutely need to run phantom power on both preamps since a transformer will not pass DC either. (The m148 for example does not use blocking capacitors, but instead uses transformers to block the 48v phantom power.)
Bottom line, this idea isn't fucked at all, it is perfectly reasonable. The only thing that is fucked is your advice.
I've also done a split with phantom on both. However you do it, keep in mind that level changes on one unit may affect levels on the other.
Do you see any problems with powering the mics and then splitting the signal...?
I've also done a split with phantom on both. However you do it, keep in mind that level changes on one unit may affect levels on the other.
Do you see any problems with powering the mics and then splitting the signal...?
I only brought it up because some people may have two preamps both with phantom and no outboard phantom available ( such as the PS2). If you have an outboard phantom unit it would probably be better to split the signal after the phantom to the two separate preamp units
If I read correctly -
He was not using the PS2 - he was expecting the V3 to do it all..
Pretty sure there is no onboard phantom on the AD-20
the idea is that phantom power can potentially color the sound of the pre and if you're doing a comp where one or both of the units does not have it's phantom on you are not really getting a true comparison of what both units sound like under actual show conditions.
Wrong...
-t fuckhead for not backing your comment w/ some actual info.
Go ahead pal - use 2 phantom sources...
The whole idea is so fucked - I dont even want to try...
the idea is that phantom power can potentially color the sound of the pre and if you're doing a comp where one or both of the units does not have it's phantom on you are not really getting a true comparison of what both units sound like under actual show conditions.
Wrong...
-t fuckhead for not backing your comment w/ some actual info.
Go ahead pal - use 2 phantom sources...
The whole idea is so fucked - I dont even want to try...
You fucking moron. You have no clue what the fuck you are talking about. I tried to play nice in this thread but you're still the same clueless jackass you've always been.
the idea is that phantom power can potentially color the sound of the pre and if you're doing a comp where one or both of the units does not have it's phantom on you are not really getting a true comparison of what both units sound like under actual show conditions.
Wrong...
the idea is that phantom power can potentially color the sound of the pre and if you're doing a comp where one or both of the units does not have it's phantom on you are not really getting a true comparison of what both units sound like under actual show conditions.
Wrong...
-t fuckhead for not backing your comment w/ some actual info.
Go ahead pal - use 2 phantom sources...
The whole idea is so fucked - I dont even want to try...
the idea is that phantom power can potentially color the sound of the pre and if you're doing a comp where one or both of the units does not have it's phantom on you are not really getting a true comparison of what both units sound like under actual show conditions.
Wrong...
-t fuckhead for not backing your comment w/ some actual info.
Go ahead pal - use 2 phantom sources...
The whole idea is so fucked - I dont even want to try...
You fucking moron. You have no clue what the fuck you are talking about. I tried to play nice in this thread but you're still the same clueless jackass you've always been.
Why use 2 phantom sorces? I defy anyone to give a reason to do this...
What was the reason? I missed it?
What was the reason? I missed it?
HOLY SHIT!!!!!!!!!!
You have got to be, hands down, the most annoying person I've met in many a years taping.
Look, forget it... a real EE (Todd R) has shown, once again, that you don't have a clue what you're talking about. You're not worth my energy...
-T for being a complete ass clown
you don't have a clue what you are talking about. how many more times do you have to be proven wrong before you will just shut the fuck up and go away?
the idea is that phantom power can potentially color the sound of the pre and if you're doing a comp where one or both of the units does not have it's phantom on you are not really getting a true comparison of what both units sound like under actual show conditions.
What was I wrong about...get back to me when you have a good reason to run two phantom sources...
Why use 2 phantom sorces? I defy anyone to give a reason to do this...
Why use 2 phantom sorces? I defy anyone to give a reason to do this...
What was I wrong about...get back to me when you have a good reason to run two phantom sources...
You were wrong when you said the idea of using 2 phantom sources was fucked. Matt and I have both explained that you were wrong and that it is perfectly acceptable and will not cause any problems.Why use 2 phantom sorces? I defy anyone to give a reason to do this...
Reasons:
1) if the mic splitter is transformer based, you will need to either use 2 phantom sources or will need to insure that the phantom you do use is on the pass through output side, not on the side that is transformer isolated. A transformer based splitter will not allow changes in impedence to change the signal level on either side of the split (as was discussed earlier). For this reason, professional sound companies running sound will use transformer based mic splitter boxes when they need to split the signal. But a transformer will not pass DC voltage, including 48v phantom.
2) Using 2 phantom sources will better insure you have adequate current available for the mics to draw from. For example, Earthworks mics are very power hungry and consume about 10ma per mic, as opposed to most mics that consume 1-2ma per mic. Many phantom power circuits do not have enough juice to power mics like these adequately. Using two phantom power sources in parallel allows power hungry mics to get the current they need to operate at their best.
3) a poor phantom design may not have adequate current available, may not provide the standard 48v, may have unacceptable levels of noise, etc. Using two sources (esp say if one was from a V3 which has good phantom powering) will mask this. The overall phantom power might be worse than using the V3 alone, but would be far better than only using the preamp with crappy phantom. So using two phantoms won't allow you to compare on the basis of phantom power, but at least it allows the mics to perform their best so the rest of your preamp comparison means something.
I guess if you know beforehand you've got one of your two preamps that is known to have good phantom power (eg the V3), you can only run the phantom on that unit alone and avoid issues with 2) and 3) above. But if you don't know anything about either preamp you're running and don't know whether either has good phantom power, by running both together you insure you have an adequate phantom power supply. And since their is no reason not to run two phantom power circuits, why not do it?
Pretty amusing thread! I must admit my kneejerk reaction was to side with corkscrew