# Condenser Mic's

#### Soundguybs

##### Member
I have a Mackie 3204 Sound Board and i am tring to get a A-T Pro 37R condenser mic to work for a overhead drum mic. I cant figer out why it is not working. I know the mic works becuase i have tested it on another sound board. It just does not work on this one. The hole sound system is wire Balanced. We use the 1/4 jacks out of the Sound board instead of the XLR out puts. Could that be why it is not working and does anyone have a way i could fix it?

#### avkid

##### Not a New User
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now let me get this straight, the A-T condenser is plugged into the SR-32 with a balanced XLR right?

#### avkid

##### Not a New User
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Soundguybs said:
We use the 1/4 jacks out of the Sound board instead of the XLR out puts. Could that be why it is not working and does anyone have a way i could fix it?
Instead of the main XLR outputs they are using the 1/4'' TRS main outs, which should have no effect on the condenser at all.
Are you using a snake or other installed cable?

#### Soundguybs

##### Member
Sorry I said output when i mean inputs. The Mic gets plug into the snake on stage using a XLR cable and the snake converts from XLR to 1/4 plugs. The 1/4 plugs are plug into the Soundboard.

#### propmonkey

##### Well-Known Member
phantom will not go through 1/4" you have to run all xlr if you want phantom.

#### mbenonis

##### Wireless Guy
Right, as propmonkey said, you will need to plug the microphone into the XLR input on the console if you wish to use the board's phantom power supply. Other than that, you could use an external phantom power supply at the stage end of the snake, or an external mic preamp at the board side of things. However, both of these solutions may prove costly.

#### The_Guest

##### Senior Team Emeritus
mbenonis said:
However, both of these solutions may prove costly.
You can purchase a phantom power supply for about $15. You can get decent solid state preamps for$50-\$100 easy, even cheaper for B-stock, used, etc. How are these solutions costly?

#### avkid

##### Not a New User
Fight Leukemia
Soundguybs said:
Sorry I said output when i mean inputs. The Mic gets plug into the snake on stage using a XLR cable and the snake converts from XLR to 1/4 plugs. The 1/4 plugs are plug into the Soundboard.
Wow, that is really weird.
I'd say it's time to call a service technician and have that snake rewired!

#### propmonkey

##### Well-Known Member
I have been talkign with my friend and helping him decided on what mics he should buy for recording. I have been looking at condensers and I know they run on phantom power and I see that most can use battries. What I am wondering is what works better, running them with phantom or running them with the battries? or does it not matter?

#### jbeutt

##### Active Member
There's no performance benefit from running condensers on 48v phantom vs battery power. So the only real difference is that you're using up batteries. Especially in a studio situation, there's no reason to use batteries for phantom power.

#### Peter

##### Well-Known Member
Ya, there isnt any real benifit either way as long as the batteries stay fresh. I also dont know if I would go as far as saying that *most* can use batteries, but a good number of them can. Phantom power is really a standard and many many many mics use it, there really only rare curcumstances where you wouldnt want to use it and would instead opt for battery power (like if your device does not supply phantom power).

#### SHARYNF

##### Well-Known Member
Here are some things to consider

At the mic it depends on the battery supply vs phantom power if the battery is internal, then usually the mic's phantom power requirements are on the low side typically since rather then attempt to derive 48volts from an internal battery, they simply use the lower voltage. So in that case performance is probably about the same, but the down side is if the battery drains down at a critical time. SO in general I prefer using phantom power

HOWEVER if your board only has global phantom power, ie like the mackie where there is phantom power on all inputs or none, then depending on your inputs and requirements it might be better to have a mic which uses its own phantom power, so that you do not have to feed phantom to devices you don't want to.

IF you are buying a mic, having an internal battery for a condenser has the advantage of flexibility in being able to be used with a device that cannot provide it externally. THAT SAID, the better mics tend NOT to have a built in battery, for instance while the AKD C1000 does, the AKG C3000b does not, or the Studio Project family do not.

Now you can get an external phantom power unit, the thing you need to watch for is that it really puts out a full 48 volts, some of them fudge a bit (the ones for instance that may use 9 volt batteries or 3 nine volt batteries MAY not put out a full 48 volts instead can be 18 or 30 volts. For some mics this is not a problem but for others it can be.

So as always there are tradeoffs

Sharyn

#### propmonkey

##### Well-Known Member
ive wonder that for awhile. im lending my friend 2 audio technica atm33a to use as overheads for drums and stuff. he has protools and he is going to be ordering a mackie preamp soon.

#### Chris15

##### CBMod
CB Mods
Departed Member
Now you can get an external phantom power unit, the thing you need to watch for is that it really puts out a full 48 volts, some of them fudge a bit (the ones for instance that may use 9 volt batteries or 3 nine volt batteries MAY not put out a full 48 volts instead can be 18 or 30 volts. For some mics this is not a problem but for others it can be.
So as always there are tradeoffs
Sharyn
I think the answer is to check the tech specs on the mic in question. Take the Shure MX412/ 418 for instance. If will happily run on any voltage between 11 and 52 volts. Other mics will run as low as 9 volts or I guess some go even lower. So a pair of series wired 9 volt battery with a pair of matched resistors and you have a quick and easy phantom supply.

Yes, 48 volts is the standard, but many products have a reasonably wide range of voltage tolerances. Aside, why is it that I have a sneaking suspicion that the number of 48 volts may have come from the telecommunications industry? I am sure that I could look it up and find why 48v is the standard if I really wanted to know though.

#### SHARYNF

##### Well-Known Member
The 48 volts goes back to the early days with tube mics etc. Also in Europe and some pro equipment there was a different system called t power that you still find on some Sennheiser shotgun mics. Sennheiser mics that do NOT have built in battery power like the MKH 416 do need the full 48 volts or else the performance will suffer.

Sometimes people get confused with Mic power and Phantom power For instance lavalier mics and a number of sony products that are used with camcorders are powered mics but NOT Phantom power and infact if you switch them around you can destroy the mic.

There are also some instances where running the full power improves the mic performance the famous RADIO SHACK pzm mic that they sold cheaply ran on a low power battery but in fact was the crown mic and if you modified the mic to run on full power the performance quality improved dramatically.
I think you will find that as you get up into the higher and higher quality mics you may find that they are more sensitive to the voltage needed;. The mic still works but the performance starts to suffer.

Sharyn

#### cutlunch

##### Active Member
Aside, why is it that I have a sneaking suspicion that the number of 48 volts may have come from the telecommunications industry? I am sure that I could look it up and find why 48v is the standard if I really wanted to know though.
Sharyn is right about the voltage being used pre-transistor. But Chris I think you maybe on to something with the telecommunications connections. The standard voltage used in telephone exchanges is 48v. This is a hang over from the electromechanical exchanges. Although if you measure across your phone lines with the phone on the hook you should read approximately 48V. It depends on how far you are from the exchange.

The voltage may also be determined by the requirements of the valves used at the time. I'll try and do more research.

More Research Done!!!

After posting this I did more research, Wikipedia, so take it with a grain of salt.
Apparently why we got the 48V was that a Norwegian radio station had some microphones made and they wanted to use them on the same supply that provided their auxillary lighting. This lighting used a 48V supply. I geusss this was in case of power cuts they could still transmitt so long as they had a generator for the transmitter?

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#### Chris15

##### CBMod
CB Mods
Departed Member
Apparently why we got the 48V was that a Norwegian radio station had some microphones made and they wanted to use them on the same supply that provided their auxillary lighting. This lighting used a 48V supply. I geusss this was in case of power cuts they could still transmitt so long as they had a generator for the transmitter?
48 volts = 4 12 volt batteries in series, or 2 24 volters. Telephone exchanges are supplied with mains at 240 and a 48 volt supply reticulated throughout. Hmm. Is it not a general thing that the separation of lighting and audio supply was a good thing...

Perhaps len or someone might be able to confirm that power over ethernet uses 48 volts also...

Oh and I forgot to add that telephones are 48 volts at the exchange. Take into account voltage drop and you will most likely find that the voltage at your premises is somewhat less...

#### SHARYNF

##### Well-Known Member
I would guess that when the spec was set up in the "dark ages" that 48 volts was more available and also the components at that time were not the effecient low voltage sort of things again at that time there was little or not transistor electronics on mics and the condensor mics did not have the pre charged type of design that came later... So I would guess that it was left over from that era and gave the designers more flexibility

Sharyn

#### saxman0317

##### Active Member
I have been talkign with my friend and helping him decided on what mics he should buy for recording. I have been looking at condensers and I know they run on phantom power and I see that most can use battries. What I am wondering is what works better, running them with phantom or running them with the battries? or does it not matter?
All my mics are non battery powered, with the exception of wireless. I just dont trust batteries enough for something thats solidly rigged somewhere that you cant get to during a show. At least lav packs you can pull real quick in the wings if the batteris die. As for my set up at home in the studio, i use two battery condensers as extras just in case since i didnt have any more phantom supplies, but when your doing studio type things where it doesnt really matter if a battery goes ddead as much, it doesnt make me as nervious.