does my AT 4050 sound like it should?

  • Thread starter Thread starter powpowmeow
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Well that depends on the chain and the mics. I'm currently using Avenson STO-2's myself in a non-typical stereo pair / ambience way. These mics are great with anything IN PROXIMITY. But as ambient mics, their own self noise in noticeable if you don't run the gain on your preamp as high as reasonable, and/or have a really loud (brass band) source to record.

Now for my DMP3 and my old AT4033a with a trombone pretty much swallowing the mic, yeah, the DMP3 pretty much never got more than one click above absolute zero. Otherwise my Delta 44 got over powered and clipping occurred. But on that same setup, I had to boost my ADC (mic) levels to near max (90%) to get the desired level in audacity. You pretty much want to avoid running at the extremes, especially on low end gear. That last 15% of gain on my laptops speaker levels is noticeably bad sounding relative to the other 85%. The low end of gain on my setup, bottom 20%, has a noise floor that's completely noticeable and unacceptable in most applications, when amplified to audible levels.

But it depends on the chain. Mic -> Preamp -> Converter -> Computer / Storage. On my Korg MR-1000 the chain except for the mics is fairly well contained and well engineered. So I have one knob for gain and some mics. I have some switches too, H or L gain boost, Phantom Power, and Limiter. A limiter is sort of a safety net, it compresses the dynamic range when you get to that danger zone of peaking your levels. For my Korg, I like to keep the source at -3 to -6 for the peaks with an average level as close to -12 as possible. Any softer and the mic self noise gets overbearing.

The AT4050 is a relatively quiet mic, with a hot input level, so you should be able to run it softer without too much damage. But distortion can come from several thngs. High SPL (loudness), there generally a pad switch on the higher end mics to help them cope with higher SPL levels. Wind, there's foam windscreens, artificial fur windscreens, pop filters, and metal grills to help cut down wind noise. For my AT4033a, I had to wrap it in a sock to use it as a vocal mic. The poor mans equivalent of a pop filter / foam windscreen.

The 4050 is an LDC aka LARGE diaphram condenser so it's more exposed to wind. And the grill is more or less to protect the capsule than to block wind. And then there's levels, which at any point in the chain can cause / contribute to clipping. To much signal from the mic and the preamp clips, too much signal from the preamp and the converters clip. Levels too high on the converters, or just not able to cope with the input level and it clips. Not that I saw any clipping on the supplied recording. So I'm more inclined to believe that the distortion in this case is either wind or levels. Or just the characteristic(s) of the sound source.

A pop filter is only meant to cut down the plossives, the start of words / syllables that are accented and sends a burst of air towards the mics. It is NOT a windscreen. It can cut down some wind, but not nearly to the same degree as other options. I'd recommend putting the pop filter further away to give the wind more time to dissipate, and/or put a sock over your mic and see if that helps. If it does then your issue is likely wind / proximity. If it doesn't and no alterations in the levels and such have any effect, it's likely the quality of the chain, or the sound source itself that is contributing to the perceived distortion. Or maybe your speakers / monitors suck and there's nothing wrong with anything else.
 
Well it's not too hard to do the math.

USB bus powered, so 5V != 48V (5V)
4x AA battery powered, so 4x1.5V != 48V (6V)
8x AA battery powered, so 8x1.5V != 48V (12V)
2x 9V battery powered, so 2x9V != 48V (18V)

That's a bit oversimplified. There's probably not a mic on the planet that would run on 5V phantom supply. The MobilePre USB puts out about 30V (unloaded), last I heard.

To get higher voltages from lower voltages, you use an inverter circuit. For all practical purposes, this amounts to either A. circuits that modulate the DC voltage with a sine wave or whatever and feed that into a transformer to step it up, then convert it back to DC or B. charge pump circuits that use a capacitor to generate the higher voltage.

Either way, inverter circuits have one fundamental property: as the voltage goes up, the current goes down. This is true for AC transformers as well, of course, but with inverter circuits, you have lower efficiency, i.e. they draw a good bit more wattage than they put out. With the paltry 500mA maximum for USB (.5A * 5V = 2.5W), it's hard to get 48V@12 mA (about .6W) for each of two inputs (about 1.2W) and still have enough power to drive the rest of the circuitry, so they compromise on the voltage and run it at... say 30V@12mA.
 
... But as ambient mics, their own self noise in noticeable if you don't run the gain on your preamp as high as reasonable, and/or have a really loud (brass band) source to record.

Now for my DMP3 and my old AT4033a with a trombone pretty much swallowing the mic, yeah, the DMP3 pretty much never got more than one click above absolute zero. Otherwise my Delta 44 got over powered and clipping occurred. But on that same setup, I had to boost my ADC (mic) levels to near max (90%) to get the desired level in audacity. ..
You have a few things that don't compute' for me here -but suffice to say the points on the importance of good gain staging are well taken. :)
Alt quickie version.
Analog front end gain targeted with the source and mic at hand for that device's nominal -it's best sig/noise (+/- gain / saturation / creative clipping' pet tricks.. :D

If the pre and converter's design levels align' the expected result is nominal record level' ie, your -18 or so full scale range (average not peak just in case

If that relationship is way off trim there. (many converters have alt settings for their analog front ends for just this purpose..)
But if it's a little low at the A/D -at 24 bit- bring it up in the record app. At his point your s/n is what it is and will come along for the ride regardless.
If the mic clips the pre -use the pad on the pre if it has one, or pad in-line on the mic line.
If you're clipping the mic pad at the mic.
 
that leaves you open to pretty much all of the standard lowend stars.

DMP3
RNP
ART MPA Gold w/tube swap

those three are the most common suggestions for under 500 although there are other options worth considering. you could definitly get a presonus MP20 for way less than that also.

Ended up going with the DMP3. On backorder til the 10th. Thanks a lot everyone who posted their feedback and help here
 
Ended up going with the DMP3. On backorder til the 10th. Thanks a lot everyone who posted their feedback and help here

Spoke too soon. Anyone know where I can get a DMP3? They are on backorder everywhere.
 

Unfortunately, they actually don't. Thanks for trying to help though.

If anyone knows where i can find a DMP3 or has a recommendation on a similar preamp please lemme know... All my recording is on hold right now because of this nonsense...

edit: found one actually in stock at 8th street music, they should have a few left if anyone is looking for a dmp3 http://www.8thstreet.com/product.asp?ProductCode=10268&Category=Audio_Processors&p=true

as an aside, I would not recommend buying anything from Front End Audio
 
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sorry for the ancient bump, but i got the dmp3, and it made a world of difference in my mic's tone on vocal takes.

i do have a new question tho, kind of a noob question - i use a pop filter attached to the mic stand -

how far should the pop filter be from the mic?

how far should my voice be from the pop filter?

which part of the mic should i be singing into? should i sing directly into the part where the small round condenser is?

thanks a lot guys!:D


edit: one more thing... i am using this mic 95% for vocals. there is a low end rolloff at 80hz, but the dmp has a 75hz cutoff. which should i be using for vocals? obviously using both at the same time is redundant
 
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sorry for the ancient bump, but i got the dmp3, and it made a world of difference in my mic's tone on vocal takes.
Hey, your thread, two whole months :p certainly not even a deal.

i do have a new question tho, kind of a noob question - i use a pop filter attached to the mic stand -

how far should the pop filter be from the mic?

how far should my voice be from the pop filter?

Don't know that it matters much. I tend to put the filter right at the mic (maybe an inche or two to do it's job?) and let the singer work the tone and distance as needed. 'Close up is full and huge/intimate, as you get several inches out it's a lighter balance and a bit more 'natural and complete picture of the sound a vocalist is making, farther starts to get some air' off the room.. Sometimes you see singer at the filter, mic back.. You pick. ;)


which part of the mic should i be singing into? should i sing directly into the part where the small round condenser is?
..the diaphram? Well, yeah. ..the front one!(?) Sometims you slide up or down or off center from there. Tone changes.


edit: one more thing... i am using this mic 95% for vocals. there is a low end rolloff at 80hz, but the dmp has a 75hz cutoff. which should i be using for vocals? obviously using both at the same time is redundant
Try it both ways (sometimes neither), they may have different slopes/tone.
 
pop filter - as close to the mic as possible and still be effective. i.e. no wind noise (breathy rumble) and no sibilance (Sssss sounds). Or far away depending on who's using it and how close you're comfortable letting them get to the mic. Generally 6" from what I've seen, but I'm an instrumentalist.

part of the mic to address - whatever gives you the sound that you're after. In your face, or distant universe depending on how the mic is addressed / positioned.
 
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