Back in September of last year, I splurged $120 on some sound kit in order to improve the quality of my podcast recordings. I’ve not regretted my purchase of the Behringer PodcaStudio USB, but I’ve often felt like I’m under-utilising it. I think I could be making adjustments to improve the sound quality I get from it; I’m just not sure what.
Last night (July 8th), I decided that it was time to educate myself. I got the user manual for the Studio’s included sound board, the Xenyx 502, out and sat down to read it.
And was blinded… with science!
The book started throwing terms like “signal path” and “input gain,” “phase shifting” and “slope at 18 dB/oct, -3 dB at 75KHz.” Dude, WTF? This is what you throw at folks who are buying a podcasting kit?
Okay, let me be fair. I didn’t get this from Dick Smith or Harvey Norman. I walked into a dedicated music store, a place whose primary clientele are sound afficionados, to get this product. Maybe there’d be an expectation of a minimum level of knowledge when it comes to one of these things.
So how do I get up to speed? How much do I need to know, and to what degree, in order to get this rig to output optimum-quality sound?
Let’s start this one step at a time:
Which Knobs Are Important?
At first blush, there are a whole heap of sockets and knobs that may or may not be important to what I’m doing. It may only be a small board, but it’s still pretty intimidating to the complete newb (like moi).
Spend a bit of time with it and you discover that the board is divided up based on a number of “lines” in and out; the number of signals the board takes in. It turns out that while there are five “lines” in, there are only three inputs from a user’s perspective: One mono input (Line 1), which is for the Behringer Ultravoice XM8500 microphone that comes with the kit, and two stereo inputs (Lines 2/3 and 4/5).
In terms of lines out, there is one, what the board calls “Main Out,” as well as a point for a stereo headphone jack. There are also two sets of stereo RCA sockets (you probably know what these look like already, but if not, see the Wikipedia entry on RCA connections) for “CD/TAPE”, which the kit’s USB sound card plugs into.
For my current purposes, LINE 1 and MAIN OUT are all I need. What, then, relates to these?
The Long Line of LINE 1
I’ve fiddled with these in the past, and I know they make a difference, but I’m not sure how or why. Time to find out:
The manual reads, “Use the GAIN control to adjust the input gain. This control should always be turned fully counterclockwise whenever you connect or disconnect a signal source to one of the inputs.”
Okay, one concept drop and a safety tip. Thank you for that, manual, but can you tell me what input gain is and under what circumstances I might want to adjust it?
A quick check of Wikipedia tells me that “gain” is a measure of amplitude, in other words, how much the board is increasing the volume of the microphone’s input. The panel tells me the gain can range from +10 (-10) to +60 (+40) but not what those numbers mean. I’m assuming they’re decibels.
Funnily enough, it’s the paragraph on the CLIP light which is instructive: when it lights up, the input from the microphone is too loud. “If this happens,” reads the manual, “use the GAIN control to reduce the preamp level until the LED does not light any more.”
Practical Use of GAIN
Aha. So the GAIN control alters the microphone’s “preamp level” and should be set so that the CLIP light doesn’t light up. That says to me that when I’m setting up for a session where I want to make sure I get good results, a sound check with an eye on that GAIN can help ensure quality. Probably not a bad idea to throw some plosives in there (the hard “p” and “t” sounds) as that’s what tends to cause clipping.
EQ HIGH and LOW
Two knobs in the EQ section, one marked HIGH 12 kHz – twelve kiloHertz – and one marked LOW 80 Hz – eighty Hertz. So this must be some form of equaliser.
The manual reads, “All mono input chanells include a 3-band equalizer, except for the 502, which is equipped with a 2-band EQ. All bands provide boost or cut of up to 15 dB. In the central position the equalizer is inactive.” It then goes on to tell me how great the circuitry of its British EQs is.
But I’m getting it. I can boost or cut the amplification of the higher or lower notes that come into the microphone. I guess it’s like the old “Bass” and “Treble” knobs you’d find in most stereos.
Practical Use of EQ
I have a voice that’s better in the lower registers; maybe it’s worth upping the LOW control a bit.
Per the above, the CLIP light goes on when the input from the microphone is too loud. I fix the situation by lowering the GAIN control.
According to the manual, “The LEVEL control determines the level of the channel signal in the main mix.” Now, this seems self explanatory – it lets you set the overall volume of the mono input as compared to the other inputs.
Practical Use of LEVEL
If I’m right, it’s worth dropping the levels on the stereo lines to nil, just so there’s no other noise from them (even though there’s nothing plugged into them).
Should I then crank the LINE 1 level to maximum? I’m not sure. There’s some amplification stuff there, which I might leave to Audacity rather than do on the board.
At first, it looks like there’s lots of important stuff here. Like Lines 2-5, there are two output jacks, a headphone jack, two pairs of RCA left/right sockets (input and output) marked CD/TAPE which the USB sound card plugs into, a power indicator, two CD/TAPE switches (CD/TAPE TO PHONES and CD/TAPE TO MIX) plus two knobs: PHONES and MAIN MIX.
Practical Use of MAIN OUT
Looking at the manual, though, this is largely useless for my purposes. PHONES controls the output volume to the headphone jack, whilst MAIN MIX controls the output volume to the pair of MAIN OUT jacks. There’s no direct control for the CD/TAPE outputs, which is where my computer takes the sound from.
What do the Xenyx 502’s buttons do for me?
Perhaps not much. A friend in the audio industry suggested I leave everything on a neutral setting and do my audio editing work in Audacity – perhaps not a bad idea. Though I’m tempted to up the gain when recording, it might introduce more audio artifacts and exaggerate any clipping issues that come up.
Still, beefing up the LOW frequency range with the equaliser seems like a good idea…
What makes a good sound check?
Are you curious?
What piece of electronic kit have you owned that you used, but didn’t really know your way around?
Are you producing?
What have you purchased to improve the quality of a product? How well or badly did it work?