XLR Microphone connected to Computer Sound Card - How?

[rickharrison]

I would like to connect an XLR microphone to my computer sound card. The computer, of course, is a 1/8" phone plug.

If you look at the XLR connector, it can appear as an inverted triangle. To pins parallel to each other, with a third pin below and centered between the top two:

1 2
3

Can I just connect two of those to the two conductors of a 1/8" phone plug? If so, which two, and to which to connections on the phone plug? (the tip and the ring, if I remember my terms correctly.)

THANKS FOR YOUR HELP!!!

A dude with Champagne Technical Tastes on a Beer Technology budget.

 

[Goat Rodeo Cowboy]

Been there. Done that. Tried it.

Very few computer sound cards will accept the miniscule signal from a microphone. They expect one of those mics you find at the computer store and has a little amplifier built in.

Get a preamp. XLR into the preamp. Preamp output goes to LINE IN on your computer. Audio Buddy and comparable devices start in the $50 to $70 range, and if you plan to do serious quality... as in Voice Over work, be prepared to someday move up to a $300 to $900 dollar preamp.

I dont do commercial work so when I moved up, I settled for something in the $150 range with built in compression. It ain't top drawer... but it's better than my voice.

 

[OttoM]

Been there. Done that. Tried it.

Very few computer sound cards will accept the miniscule signal from a microphone. They expect one of those mics you find at the computer store and has a little amplifier built in.

That's not completely true.

A dynamic (non-condenser) XLR-connector microphone works just fine with most computer sound cards. Get a cable like this to connect it:
http://www.google.com/search?q=hosa+xvm105

Now to be fair, the preamp in a computer sound card doesn't have the quality of a standalone preamp - but it does work.

 

[OKCRadioGuy]

If somehow you can afford it, I would seriously consider one of those Sampson mics with a USB colnnection on them. I played with one of them at the NAB and loved it. If I was just doing V/O work I think it would be the weapon of choice as they are really pretty cheap for what they do.

 

[rew]

Some form of a preamp is the best way to do it,but if you want to try using just the mic I think the wireing for the cable will be pins 1 and 3 to the shield of the cable or the ground and pin 2 is the tip of the plug. I may have pins 2 and 3 swapped. I never can remember which pin is + on the XLR plugs. In this case it should work either way.

 

[OttoM]

Some form of a preamp is the best way to do it,but if you want to try using just the mic I think the wireing for the cable will be pins 1 and 3 to the shield of the cable or the ground and pin 2 is the tip of the plug. I may have pins 2 and 3 swapped.

You are correct - 2 is hot, 3 is cold and 1 is shield. Some mic inputs like to see the shield on the sleeve of a TRS connector and you'll know right away if that is required if you hear a low hum.

 

[Goat Rodeo Cowboy]

On an XLR 1 is ground. Connect it to shield on the cable to the 1/8th inch plug. Pins 2 and 3 are mic signal. It is trditional to connect 2 to the tire that goes to the "tip" of the 1/8th and then 3 would connect to ground. Normally reversing 2 and 3 is not a fatal error.

Note to Rob Stutson: Sound card manufacturers seem to take liberties. Some have both a mic in and a line in, some do not. It has been a few years since I went through this testing process trying to reverse engineer what the card expects. It could be that today's typical cards work the way you are describing.

The unknown about a mic input to a typical sound card: Does it expect a two connector tip and sleeve plug and wire, or does it expect a 3 conductor tip-ring-sleeve plug and wire. It has been traditional to put a voltage on the ring which is used by those computer store computer mics. If you have a cable cut open so you can access the individual wires, a quick check with a volt-ohm-multimeter will tell you if the voltage is present.

 

[OttoM]

Note to Rob Stutson: Sound card manufacturers seem to take liberties. Some have both a mic in and a line in, some do not. It has been a few years since I went through this testing process trying to reverse engineer what the card expects. It could be that today's typical cards work the way you are describing.

Actually, I've never had any problem interfacing an XLR-connected mic to a computer sound card in the 15+ years I've worked with computers. So I'd say "today's cards" work the same as the older ones do.

Most desktop computers have both line and mic inputs and if you connect a mic to the line input it would behave as you've experienced. Since 2001 most laptops come with only a mic input, so the chances of selecting the wrong input are greatly reduced.

The unknown about a mic input to a typical sound card: Does it expect a two connector tip and sleeve plug and wire, or does it expect a 3 conductor tip-ring-sleeve plug and wire.

Well let's see what the experts say. From "Interfacing Professional Microphones to Computer Sound Cards" (http://www.shure.com/ProAudio/Products/us_pro_ea_connectingmics):

"Sometimes it is impossible to tell if the connector on a sound card is of the mono or stereo variety. If a cable that is equipped with a mono connector is plugged into a sound card input that uses a stereo connector, the microphone should still work. This is because the Ring portion of the sound card jack will make contact with the Sleeve portion of the miniplug on the mic cable, which will connect any dc bias voltage to ground."


By the way: To the poster who started the thread - you might want to get this document as it has all the info you need to build a cable that will work with your computer.

 

[radioguybroadcasting]

If somehow you can afford it, I would seriously consider one of those Sampson mics with a USB colnnection on them. I played with one of them at the NAB and loved it. If I was just doing V/O work I think it would be the weapon of choice as they are really pretty cheap for what they do.

They run a little hot and are abd at reducing background noise, for for like $40 the Samson Q1U USB mic isn't too bad.

 

[radioguybroadcasting]

I would like to connect an XLR microphone to my computer sound card. The computer, of course, is a 1/8" phone plug.

If you look at the XLR connector, it can appear as an inverted triangle. To pins parallel to each other, with a third pin below and centered between the top two:

1 2
3

Can I just connect two of those to the two conductors of a 1/8" phone plug? If so, which two, and to which to connections on the phone plug? (the tip and the ring, if I remember my terms correctly.)

THANKS FOR YOUR HELP!!!

A dude with Champagne Technical Tastes on a Beer Technology budget.

Go to Radio Shack, get an adapter with an xlr on one end and rca cable on the other and rca to 1/8"

 

[nmoore6676]

Actually it is best if you are doing serious work to get a converter to run your mike into the USB or Firewire (if you have one) ports. There are several sources on line if you check. If you are going to eventually use multiple mikes or other sources there are mixers with a built in USB (and/or firewire) converter. There are also professional sound cards available with XLR inputs. The idea is to get good analog to digital conversion which these converters are designed to do.

The built in sound card and especially the on board ones will not give you good audio results for anything but on line chats and such. For those you can just get a cheap computer mike and it will sound as good. The old silk purse out of a sow's ear addage applies here.

 

[Goat Rodeo Cowboy]

The built in sound card and especially the on board ones will not give you good audio results for anything but on line chats and such. For those you can just get a cheap computer mike and it will sound as good. The old silk purse out of a sow's ear addage applies here.

I would suggest to you that your blanket statement about built-in cards tries to cover too much ground.

The last computer I bought did not like my (low end) professional grade card. There is some kind of conflict between my pro-card, the drivers for the built in card, and the XP Media Center Edition operating system. After several less-than-pleasant conversations with customer service for the computer and the GOOD sound card, I decided to just use the built-in on-the-motherboard sound card device until I could decide on a fix or a new quality card. I create quality voice recordings. Once in a while I drag the thing out for an on site recording of soloists, pipe organ and other events.

Maybe I have a tin ear, but the good-for-nothing built in card is performing like a champ. Suggestion: "Dance with the one whut brung you" until you are able to demonstrate the card just doesn't have what it takes.

 

[Goat Rodeo Cowboy]

Actually, I've never had any problem interfacing an XLR-connected mic to a computer sound card in the 15+ years I've worked with computers. So I'd say "today's cards" work the same as the older ones do.

Most desktop computers have both line and mic inputs and if you connect a mic to the line input it would behave as you've experienced. Since 2001 most laptops come with only a mic input, so the chances of selecting the wrong input are greatly reduced.


Well let's see what the experts say. From "Interfacing Professional Microphones to Computer Sound Cards" (http://www.shure.com/ProAudio/Products/us_pro_ea_connectingmics):

I don't know what I said that caused you to be so adamant that I was wrong, wrong, wrong. What's up with that? ;D

I went to the Shure site to which you provided a link. Right up at the top Shure said:

Professional microphones put out a very weak signal - less than 1/1000th of a volt, or 1 millivolt. Audio inputs on sound cards, even though they may be labeled "Mic In" or be identified by a small microphone-shaped icon, often are not designed to accept such a low signal level. Most sound card inputs require a minimum signal level of at least 1/100th of a volt (10 millivolts); some older 8-bit cards need 1/10th of a volt (100 millivolts). This discrepancy means that if a typical professional microphone is connected to a sound card input, the user will have to shout into the microphone or hold it just an inch or so away (or both) in order to produce a strong enough signal for the sound card to "hear."

How is that so different than what I said? I said, and Shure said: "There are a lot of differences in sound cards. Try some suggestions and see what works for you."

What is it the humanitarian worker tend to say? "Give a hungry man a fish and cure his hunger for today. Teach a hungry man how to fish and cure his hunger for a lifetime."

My posts taken as a group along with what some other folks had to say are an effort to prepare a person "hungry to fish for sound" how to go fishing with their sound card.

 

[surfdude]

"Maybe I have a tin ear, but the good-for-nothing built in card is performing like a champ. Suggestion: "Dance with the one whut brung you" until you are able to demonstrate the card just doesn't have what it takes"

Right you are! I voice spots for two national clients using these onboard cards...

"Realtek" on a Gateway laptop
"Soundblaster Audigy 2" on a Dell

They work fine. In my studio I have a $700 Lynx soundcard, and I hear no sonic difference on voice.
The noise floor is about the same.

Maybe the old built-in soundcards were lousy, but the modern stuff is fine for voice input.

Back to the original post. Buy an ART USB mic pre. $99. They sound very good and give you some tone
options with tube and filtering.

 

[radiorob2.0]

Go to Radio Shack, get an adapter with an xlr on one end and rca cable on the other and rca to 1/8"

Rat Shack doesn't sell that animal but they sell the parts. Also, be very careful what you plug into that 1/8 jack. If I remember correctly, there is a little voltage on that jack to feed the cheap condenser computer mics. Improper shorting isn't recommended. The Shure link (http://www.shure.com/ProAudio/Products/us_pro_ea_connectingmics) is a good reference as well as rane.com. Long story short, you can make it work.

I'll second the plug for the Samson USB mic. It sounds good and perfect for recording a client in the field. The A.R.T. is worth a look, I have had good luck with their products.

 

[Goat Rodeo Cowboy]

There are several other mics in addition to the Samson. One I have noticed is the Audio-technica AT2020. For someone who plans to do all their recording with the mic near the computer, and one mic will pick-up what you want, the USB MIC is probably the most cost effective way to go, and one that does not require a strong hardware-troubleshooting mind to keep working. Recording yourself playing a musical instrument and/or singing works well. Voice-over announcing works well. Podcasting works well. Here are the limitations that creates a problem for me: What is the maximum length of a USB cable? How would I mix two or three mics at once?

I sometimes drag a computer to a meeting, a lecture, a religious gathering or a music recital where my computer cannot (gracefully) be only a USB cord length from the source of the sound. I also carry interface equipment to patch into the existing house sound system.

For those who currently have NO equipment to plug into their computer and want to get started and learn mic technicque, learn voice technique, and learn recording and editing software technique, the USB mic is a great starting point. Then, if you later feel you have outgrown the features of the "single, short leash" mic, you know what is important to you and what questions to ask as you move up to a larger setup or a higher quality setup.

Back in my memory somewhere I think I recall one of the "big time" mic companies offering a mic in the $10,000 price range with or without the USB feature.... so don't just think of the USB connection as ONLY a beginner or low-end option.

 

[nmoore6676]

The built in sound card and especially the on board ones will not give you good audio results for anything but on line chats and such. For those you can just get a cheap computer mike and it will sound as good. The old silk purse out of a sow's ear addage applies here.

I would suggest to you that your blanket statement about built-in cards tries to cover too much ground.

The last computer I bought did not like my (low end) professional grade card. There is some kind of conflict between my pro-card, the drivers for the built in card, and the XP Media Center Edition operating system. After several less-than-pleasant conversations with customer service for the computer and the GOOD sound card, I decided to just use the built-in on-the-motherboard sound card device until I could decide on a fix or a new quality card. I create quality voice recordings. Once in a while I drag the thing out for an on site recording of soloists, pipe organ and other events.

Maybe I have a tin ear, but the good-for-nothing built in card is performing like a champ. Suggestion: "Dance with the one whut brung you" until you are able to demonstrate the card just doesn't have what it takes.

I am not sure how "I cover too much ground" but my comments were based upon my personal experience and that of Leo LaPorte, who has a computer call in talk show on KFI (now syndicated) and he also produces several Internet broadcasts and podcasts and has built a "home studio" to do so. The built in sound cards are not intended for pro quality audio, however it is always possible to get one that "sounds good".

Then there is also the ground issue, my experience has been that for a microphone, even the el cheapos for computer use they tend to be hummy. I have a Shure SM-58 withan XLR to 1/8" cable and it sounds ok for dictation but if I turn up the volume I can hear a buzzy hum and if the mike gets close to a CRT monitor all bets are off.

My comments were also based upon the premise that the original poster wanted something resembling professional results, but if for example you are just recording a Church service for those who can't get to the service or archiving and there is no budget I say go to it with whatever you got in the box. However there are converters to take balanced audio and digitize it then connect into the USB port and they can be found affordably. If you do try another sound card on top of the built in (on the motherboard) you will get into IRQ conflicts. You need to uninstall the original using the Windows hardware Wizard. That can still be problematic as you can not physically remove it like one of the card slot units and is not for the faint at heart.

 

[rickharrison]

Thanks for all the info. Actually, I am not wanting to record any voice work. All I want to do is use Dragon Naturally Speaking do help me with my typing.

I happen to own two good microphones - a Sennheiser MD421 and a Shure SM-58. I don't5 like wearing heaphones, so I don't like using the Headset and Mic that came with the Dragon software. I am hoping that I can make one of those mics work. Yeah, a friend of mine laments the use of a MD-421 for this use - like someone said "Dance with them what brung ya." I own it, its paid for, so I would like to use it.