Dual vocal mics bleeding onto each other + latency

B

barbquebutt

New member
Hi all. I hate to pull the noob card, but I've searched for an hour and I can just not find the answer I need. So hopefully someone can help me.

My problem is this; My friend and I have a podcast and we recently upgraded from using my laptop's internal mic to using two Blue Snowball microphones. When we recorded for the first time with them, there was a serious bleeding problem where we were picking each other up on our mics clear as day. On top of that, there is a latency that grows as time goes on, as in there is none when we start, but within 5 minutes, there is a significant delay between the mics causing a serious echo effect.

Here is what we're working with:
- Computer: Dell Inspirion N5110
- Recording Software: NCH MixPad v. 3.15
- Editing Software: Audacity v. 2.0.4
- Microphones: Blue Snowball (connected via onboard USB ports on laptop)

Not sure what other information would help, but if I'm missing something let me know.

Anyway, I really have no clue what to do. I've searched the internet high and low for a solution, but I can't seem to come up with anything. I suppose the latency/echo problem is the bigger problem, but I'd like to have a solution to both.

PLEASE HELP!!

Thanks!
 
Well, the bleeding problem can be solved with mic positioning. The Snowball mics are a cardioid pattern which means the pickup is mainly at the front of the mic, gradually tapering of to practically none at the back. If you position yourselves facing each other with the "null" at the rear of the mic facing the other guy, pickup will be greatly reduced (though not eliminated since there will be echo in the room).

To this you can also help by using the way sound works--levels follow what's known as the "inverse square law". This means that every time you double the distance from a sound source, the level is reduced to a quarter--so, if you're 2 feet apart to start with, if you can change that to 4 feet there'll only be a quarter as much sound getting from one mic to the other.

Finally, I don't know the software you're using but, if possible, I'd suggest putting each mic on a separate track and mixing later, allowing you to adjust levels when you edit.

Latency, on the other hand, is harder because I fear you have the wrong tools for the job. With two USB mics, each is running to it's own word clock (time reference) without any sync to the other. For anything more than a single mic, you'd have been better off buying a basic two channel USB interface and two conventional mics with XLR outputs. I can't think of any way to correct time drift when using two separate USB ports--but it might be less of an issue if you can reduce the bleed as noted above.
 
Bobbsy said:
Well, the bleeding problem can be solved with mic positioning. The Snowball mics are a cardioid pattern which means the pickup is mainly at the front of the mic, gradually tapering of to practically none at the back. If you position yourselves facing each other with the "null" at the rear of the mic facing the other guy, pickup will be greatly reduced (though not eliminated since there will be echo in the room).

To this you can also help by using the way sound works--levels follow what's known as the "inverse square law". This means that every time you double the distance from a sound source, the level is reduced to a quarter--so, if you're 2 feet apart to start with, if you can change that to 4 feet there'll only be a quarter as much sound getting from one mic to the other.

Finally, I don't know the software you're using but, if possible, I'd suggest putting each mic on a separate track and mixing later, allowing you to adjust levels when you edit.

Latency, on the other hand, is harder because I fear you have the wrong tools for the job. With two USB mics, each is running to it's own word clock (time reference) without any sync to the other. For anything more than a single mic, you'd have been better off buying a basic two channel USB interface and two conventional mics with XLR outputs. I can't think of any way to correct time drift when using two separate USB ports--but it might be less of an issue if you can reduce the bleed as noted above.
Click to expand...
Hmm. Well that's a little upsetting. We actually did record on separate tracks so that we could adjust them individually.

But I will definitely try out repositioning. I also considered putting up some makeshift acoustic barriers around the mics to see if that helps at all.

Thanks for the info!
 
barbquebutt said:
Hmm. Well that's a little upsetting. We actually did record on separate tracks so that we could adjust them individually.

But I will definitely try out repositioning. I also considered putting up some makeshift acoustic barriers around the mics to see if that helps at all.

Thanks for the info!
Click to expand...


Word of caution...an acoustic barrier behind the mics between the two of you would be fine (as would anything you can do to prevent room reflections--thick curtains and so on). However, putting anything AROUND the mic will give you a nasty boxy tone--not recommended at all.
 
Minimizing bleed is a matter of getting closer to your mic and farther from the other mic, aiming the mic at the source and the source at the mic.

You need a pair of conventional mics and an interface. As far as I know the only way to use multiple USB audio devices is with Aggregate Device on a Mac. At least one of the mics would be resampled on the fly.
 
There are a few DAWs that seem to be able to work with 2 (or more) USB ports on Windows--I've never bothered trying to list which they are though since it's such a bad idea. It has to be MME though--and sync is a big issue as seen here.
 
If this is what you are intending to do, I would get rid of the snowballs and get a couple normal mics and a two channel interface.

Also, if you watch video of radio hosts, you will notice that they are really close to their mics, almost touching. That is one of the ways they avoid bleed. The closer you are, the less gain you need, the less sensitive the mic is, the less 'room' it picks up.

(question: how do you adjust thr gain on a usb mic?)
 
Bobbsy said:
... Latency, on the other hand, is harder because I fear you have the wrong tools for the job. With two USB mics, each is running to it's own word clock (time reference) without any sync to the other. For anything more than a single mic, you'd have been better off buying a basic two channel USB interface and two conventional mics with XLR outputs. I can't think of any way to correct time drift when using two separate USB ports--but it might be less of an issue if you can reduce the bleed as noted above.
Click to expand...
I'm thinking this ^^^

I suggest getting regular/better podcast software and using a two mic interface like a Focusrite Scarlett 2i2. Keep in mind I could be totally wrong, but I think this would solve multiple problems for you. You wouldn't have to have high quality mics, but certainly face them opposite each other, and the other room dampening techniques suggested.
 
witzendoz said:
Are you actually sure that you had the tracks separated? Did 1 mic go to each track or did they both go to both tracks?

Alan.
Click to expand...
Yes, they were separate. Made a lot of pre-recording checks to verify that.

RustyMetal said:
I'm thinking this ^^^

I suggest getting regular/better podcast software and using a two mic interface like a Focusrite Scarlett 2i2. Keep in mind I could be totally wrong, but I think this would solve multiple problems for you. You wouldn't have to have high quality mics, but certainly face them opposite each other, and the other room dampening techniques suggested.
Click to expand...
Can you recommend some better software? MixPad was just one that I spotted that was accessible and had 2 mic potential, but I'm not married to it.

Thanks for the help from everyone that has replied.
 
barbquebutt said:
Yes, they were separate. Made a lot of pre-recording checks to verify that.

Can you recommend some better software? MixPad was just one that I spotted that was accessible and had 2 mic potential, but I'm not married to it.

Thanks for the help from everyone that has replied.
Click to expand...

This link has a comparison review. - Podcast Software Review 2014 | Best Podcasting Software | Radio, Video, Music, Audio Podcast Software - TopTenREVIEWS

I would think even freeware would be good enough for what you're doing - I don't know what OS you're using so I'll list a few for Windows XP +later:
* Golden Ear Podcasting Software
* Juice Podcasting Software
* Podifier Podcasting Software
* PodNova Podcasting Software

Download Ref: BEHRINGER: U-Control-Downloads

Google each up and see which one may seem like the best for your situation. And if you ever have guest speakers and need more mic preamps and want onboard live mixing of each track, you might be better off with a usb mixer. You can figure out exactly what you need for how you're going to do it.
 
Probably should understand mic polar patterns in there as well... so for a standard cardioid patterned mic, being 6 feet apart and directly opposite is going to be better, I'd assume, than being 6 feet apart and side by side... or facing away, or one behind each other.

Now you'd probably naturally do that anyway so you can see each other, which is most likely important for what you're doing.... but worthwhile understanding why you SHOULD do it.
 
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