RCA to USB or Line In?

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wcypodcast
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RCA to USB or Line In?

Post by wcypodcast » Sat Apr 30, 2016 1:44 pm

Since I started podcasting 4 years ago, I've used the setup my guide gave me. XLR mic to mixer, RCA cords out to a USB convertor and the convertor into the computer. This has worked fine, but the issue and question I have is this: I always have to use "amplify" and it always wants to increase the audio levels by 12dB at the very least. If I just go line in (from mixer to computer the levels are pretty much fine. Should I continue to use the RCA method over line in? Am I doing something wrong since the RCA to USB recordings are always so low (in terms of levels dB)? Any insight into this would be rad. Thanks everyone!

RJ

flynwill
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Re: RCA to USB or Line In?

Post by flynwill » Sat Apr 30, 2016 2:40 pm

Tell us a bit more about the particular equipment. What model microphone, what model mixer, which USB interface. Computer model and soundcard model (if you know).

In the end the absolute magnitude of the recording is not what's important. What is important is the signal to noise ratio, the difference between your voice and the background noise from the electronics. Internal soundcards are notoriously bad noise-wise due to the noisy environment inside the computer. But there are good soundcards out there and your machine may well be equipped with a better one. USB interfaces can be quite a bit better unless the succumb to the 1kHz whine that can happen (search this forum for "frying mosquitoes").

So I would say use the path that gets you the best final recording.

wcypodcast
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Re: RCA to USB or Line In?

Post by wcypodcast » Sat Apr 30, 2016 2:59 pm

Thanks for the response. So here is what I am using:

MXL 990 condenser XLR mic
Xenyx 1202 Mixer (powered)
Behring UCA200 Ucontrol (RCA to USB)

All going into my iMAC (mid2011)
I'm not sure on the internal sound card.

flynwill
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Re: RCA to USB or Line In?

Post by flynwill » Sun May 01, 2016 3:32 pm

Hmm well I would expect that Xenyx mixer to have no problem driving the USC-200 into clipping.

The UCA-20x units do not have any input level adjustment. On windows machines the windows OS does present a input level control, and it shows up as an adjustable slider which should always be set to the maximum. I just verified that on my own Mac there is no input level adjustment presented for my USC-202, so hopefully that's the case for your setup as well, but there is a slider turn it all the way up.

When you are using the USC-20x how does the level as shown by the led's on the Xenyx compare with the meters in Audacity? I would expect them to hit the yellow range at about the same time.

There are 3 controls on the Xenyx that effect the output level from a microphone, I would start with the main fader at "0", the channel level at "0", and then turn up the trim until the leds are bouncing into the yellow on the Xenyx, then once the trim is set use the main fader for any minor adjustments.

But back to the original question I would say post sample uncorrected recordings with both setups -- you can post about a 10 second mono wav file. The test recording should have 3-4 seconds of silence (hold your breath) and then speak in a normal tone.

kozikowski
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Re: RCA to USB or Line In?

Post by kozikowski » Mon May 02, 2016 10:02 am

Macs with a stereo Line-In (on the left)...

Image

...have worked very well for me. They don't have USB problems and it's one less device to worry about. I did have power noise on a very old Mac laptop, but it responded to flipping the power cord over or not using shore power during the recording. Your iMac may not be able to flip the cord over and it doesn't have batteries.

This is a radio broadcast I shot like that.

Image

Analog mixer and microphones and no UCA-202 adapter (in my case).

But yes, do post a sound test—both ways.

http://www.kozco.com/tech/audacity/Test ... _Clip.html

Koz

kozikowski
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Re: RCA to USB or Line In?

Post by kozikowski » Mon May 02, 2016 10:06 am

Line-In is how Pando Podcast does it. The Mac on the left is their transmission computer.

Koz

Image

kozikowski
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Re: RCA to USB or Line In?

Post by kozikowski » Mon May 02, 2016 6:52 pm

A cautionary note.

Newer Macs may not have Stereo Line-In any more and even if your Windows machine does have stereo Line-In, it's not expected to work very well. Most machines either Mac or Windows have a microphone connection (pink) for Skype, Chat and conferencing and that's the end of the story. The blue connection is missing.

Image

Skype is much more popular than transferring Grateful Dead cassettes.

Newer machines are stuck with a stereo USB interface such as the UCA-202 or equivalent. You have no choice. I know nothing about the UCA200. I have two UCSA202s.

http://forum.audacityteam.org/viewtopic.php?f=27&t=9477

The current Mac Mini does still have the Stereo Line-In connection!! Amazing but true.

Koz

wcypodcast
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Re: RCA to USB or Line In?

Post by wcypodcast » Mon May 02, 2016 7:25 pm

Im using an iMac, not a macbook.

kozikowski
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Re: RCA to USB or Line In?

Post by kozikowski » Mon May 02, 2016 10:33 pm

Do you have a connector that looks like a circle with two black arrows (above)? I would use that.

Koz

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