What is a 10db attenuator and High pass filter?

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Shanelor

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Hi, so my AT4040 microphone has 2 switches on it, and i am not sure what i should have them on, i tried to google the meanings of the 2 but i cant really find a good a definition.

What does the 10db attenuator do?

and the "high pass filter" has either a straight line or a squiggly line i can set it to, im guessing the squiggly line is the high pass? What would either of these do?

What should i set them on for vocals?

also what should i set them on if i am going to be using it for a temporary kick drum mic (keeping it a few feet from the actual drum) ?

thanks!!
 
These switches depend on what you are planning to record - the -10db switch will reduce the level by 10db - useful if you have a screaming vocalist or a loud sound source.
the 80hz high pass filter will cut rumble and very low unwanted bass sounds - again useful for vocals or electric guitar.
The thing with these switches is suck it and see though...
If you are recording and the sound is too hot use the -10db or if there is an unpleasent rumble use the high pass.
Good luck
 
The -10 dB pad reduces the signal going through the electronic circuit in your condenser mic to prevent clipping from a loud signal. If the signal is so loud that it overloads the actual capsule, it won't help, but it will reduce clipping in the circuit that comes after the capsule.

The high pass filter is better thought of as a low frequency roll off. It's there to reduce the proximity effect (bass buildup) caused by close miking with a cardioid or any pressure gradient mic pattern.

Best positions are usually off (0 dB and flat line), then use your ears to figure out if there's too much bass (turn the low cut filter on), or if the signal sounds distorted (switch to the -10 dB position).
 
Thanks guys!

I had the 10db on and the "Squiggly line" on, i switched them both off and hopefully i'll get a better sound now! Just waiting for my interface to come in the mail today!

I really appreciate the thorough answers :]
 
If you don't need them, turn them off.

-10dB pad makes the output signal weaker so you play nicer down the chain. It also increases the noise floor since your preamps might have to add more gain.

HPF is the frequencies that you want to keep. So if you're getting a lot of wind noise, electrical humm, and other handling type noises, it can be useful to engage it to otherwise ignore the low end where most of those happen. You can also do this in post so no reason to use it, unless it will help you drive the gain higher on site, and therefor reduce some of the noise of the gear. With a cost, since no low frequencies doesn't fair well for kick drum, tuba, bass, and other instruments that dwell in that frequency range.
 
Shanelor said:
Thanks guys!

I had the 10db on and the "Squiggly line" on, i switched them both off and hopefully i'll get a better sound now! Just waiting for my interface to come in the mail today!

I really appreciate the thorough answers :]
Click to expand...

Probably not the right decision.

An attenuator 'turns down' the output from your microphone. If you are recording something that is so loud that it overpowers your microphone pre-amp you will want to turn it on. This may be the case if you are recording a guitar amplifier or drums. It is needed (but only when) what you are recording is REAL loud.

Just noticed that you are a drummer. You will want to carefully evaluate the recorded sounds you get with the 10Db pad on and off...

There are three main types of filters (until the development of modern parametric equalizers complicated the answer). There are the high-pass, band-pass, and low-pass filters. A filter (in this context) blocks out some frequencies and passes other frequencies. Low-pass filters let low frequencies through and block high frequencies. Band-pass filters allow frequencies between a designed low frequency and the corresponding high frequency limit to pass through, while blocking frequencies that are higher than the high frequency limit and those that are lower than the low frequency limit.

A high-pass filter passes frequencies above some threshold through while blocking those below. Just because of how it works, your microphone is already a band-pass filter (look up its frequency response specification). Turning on the high-pass filter blocks (or at least reduces) sounds below a specified frequency (you can also find this on your microphone's spec sheet).

For normal recording you should always use the high-pass filter (unless you are recording something that you want the low frequency components of like bass guitar or drums). Editing out low frequency noise after tracking causes a lot of issues that can be solved by eliminating them at the source. Unintentional low-frequency components consume a lot more headroom than you would ever think and cause problems in mixing and normalizing. They can muddy things up in a way that is real difficult to find the cause later in the audio chain.
 
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Thank guys! I have an AKG P220 and I always wondered what these switches do. I'm still a beginner music producer and all this information helps, thanks again :)
 
As an aside, I've always thought a high pass filter might be more helpfully called a "low cut" filter because that's really what you're using it for: cutting off the very low frequencies. It's just something you get used to.

As others have said, leave both switches off unless you have a very good reason. Don't forget that you can reduce the level (unless you've gone into clipping) and add a high pass filter while mixing and have more control over exactly how they're used.
 
In case you were wondering, 10dB is a reduction of times 3 (X 0.3162 to be pedantic) and so the specified output of the mic will be cut from 25mV to about 8mV. That latter figure is still quite hot for a microphone, most dynamic mics will deliver only 1/4 to 1/3 of that. I don't know which AI you are getting but even with the pad engaged a kick drum or amp could still give you trouble. AI makers tend to err on the side of low noise and "adequate" headroom* which is fair enough because it IS the most useful compromise for most people.

As has been said, it is probably best to keep the HPF engaged all the time unless you are recording a bass instruments. For instance, the 6 string guitar does not get below 80Hz. Almost always better to lose the "mud"!

*As you are (WTGR!) "technical jargon challenged" a few pointers? "Headroom" is the level ABOVE "operating level" in an ANALOGUE system (a mixer say) before serious distortion kicks in. The "pro" OL is +4dBu, about a volt and the very lowest headroom in such a system would be +20dBu or 7.75V (the funny figures come about due to a daft remnant of a long unused connection regime. I am pleased to say the industry I was associated with, guitar amps, used the far more logical and cool dBV!)

Digital systems do not really have headroom. In your DAW software 0dBFS (Full Scale) equates to maximum input and output or where all the bits are used up. There is no real standard for HR kit at to where OL should be just record so the average level is at around -18dBFS and turn the monitor feed up or down to taste!

Big, BIG subject. Google, try to learn but above all, come back here for the full SP!

Dave.
 
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