Eq confused

[maxman65]

Still cant get clear info about the eq in the dp008ex. It's definately 2 band and I think shelf . So I cut 12 dB at1.6khz on the high shelf what is that actually cutting besides that frequency?

 

[rob aylestone]

Unless you know the Q of the filter the slope you get varies from make to make, and Tascam don't put the specification for the EQ in the manual. You could find out by recording some tones and measuring them, which would let you plot a graph of how the EQ works? Would that help? I think most of us rarely know for certain what frequencies are being tweaked and even fewer know how much - it usually sounds nice (or not).

 

[maxman65]

Ok but in principle what is shelf EQ doing . Does it cut outside of the designated frequency selected

 

[rob aylestone]

My understanding of a shelf filter is that it does pretty much the same as a LPF or HPF above or below a frequency, all content is removed - I tend to use these types on things like drum overheads or in my case, my own voice where I am also playing bass, and the vocal mic picks up the bass amp behind me. The difference between brands is often how steep the slope of the cut is. I'd prefer a very steep one - so it savagely wipes out the bass, or the annoying stuff up top where they spoil the sound I want. Some like on the behringer X32 seem quite good at this, but never quite as good in Cubase, I note. So no boost or cut above the selected frequency, then as much as possible below (or the reverse)

 

[Steenamaroo]

The attached image shows a shelf used to cut low frequencies,
and another shelf used to boost higher frequencies.

The gain setting determines the level of the flat part and the Q setting, if you have one, will determine the steepness of the slope.

You can effectively use a shelf as a high pass or low pass filter by pulling the gain of your shelf as far negative as it goes.

 

[maxman65]

Ok. but in simple terms a shelf EQ will cut also either side of a targeted cut to either a greater or lesser extent

 

[Steenamaroo]

Those are some of the least simple terms I've ever heard.

My picture has a high shelf boosting frequencies above X,
and a low shelf cutting frequencies below X.

That's two of the four possible shelf options.
I could have shown a high shelf cutting and a low shelf boosting.

High shelf turns up, or down, everything above X by the same amount.
Low shelf turns up, or down, everything below X by the same amount.

They put a bit of a gradient/taper in there to make it sound more musical but, other than that, it's that simple.

 

[maxman65]

I'm not in daw for this so there's no graphic representation as such. Can you interepret what the machine might be doing here

 

[maxman65]

Ie does the high band at 1.7 mean ONLY 1.7 or some arbitrary tascam range beyond that number

 

[maxman65]

Basically I just need some broad brushstroke idea of what the machine thinks it's doing in principle ie ONLY 1.7 or a range

 

[Steenamaroo]

I don't know that unit so I'm making an educated guess, but those look like controls for two shelves,
or a two band shelf.

Hi-F would be high shelf frequency - the point above which everything is turned up or down.
Hi-G would be high shelf gain - how much it's turned up or down.

Lo-F would be low shelf frequency - the point below which everything is turned up or down.
Lo-G would be low shelf gain - how much it's turned up or down.


If I'm correct then my picture, as an example, would equate to approximately
Hi-F : 1k
Hi-G : 5dB

Lo-F : 200
Lo-G : -45dB

I'm heavily rounding but you get the idea, I'm sure.

 

[maxman65]

Ok so in both case it cuts the value chosen and a cut (to a lesser amount )above the stated frequency. I'm presuming you mean minus 5db there ?

 

[maxman65]

Apologies just read it again high shelf cuts above low shelf cuts below

 

[maxman65]

So basically what I seem to have done there is chosen an almost identical frequency in both cases to get it cutting on either side . Ie I guess that would be mids and uppers mids

 

[maxman65]

So you could view a shelf EQ as a right angle triangle which if butted together at the same frequency gives you a pyramid cut type effect

 

[Steenamaroo]

The EQs I'm using here don't let me have a low shelf starting at such a high frequency,
but what you have programmed in would look similar to this.

 

[maxman65]

That

 

[Steenamaroo]

The low shelf (low frequency shelf) would be the one of the left.
In both my images frequency is indicated, rising, from left to right.

 

[maxman65]

Yes but that's the idea I guess a kind of triangle that falls off the cliff at the chosen value then another triangle which either joins it or cuts in some other place with a non equed bit in the middle

 

[Steenamaroo]

Nothing falls off a cliff, unless you set the gain to negative infinite or as low as it goes.

All frequencies above, or below, your chosen frequency are raised, or lowered, by your gain setting.
The result is something that resembles a shelf...long, straight, flat.

It sounds like you're focussing on the transition? Ignore that.