MClass as low pass filter

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mind2069
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21 Jan 2015

Hi

Can the mclass sort of simulate a low pass filter

Like setting the low self Q to lowest, and low self gain to -12db

Does this sort of equates a 12 db/oct LPF

I know is not exactly the same but is that the meaning of the XX db/oct in a LPF

If I wanted a 6 db/oct LPF I would set the low self gain to -6db

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rcbuse
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21 Jan 2015

The MClass EQ has adjustable Q and Gain, so those combined together set your rolloff slope.  Filters that are specified in 6,12, or 24 db/oct have a fixed rolloff.  But the real question is, why does that matter?  The way is sounds is what matters.

Edit:
Also, a typical low pass filter will block everything above the cutoff, the MClass EQ is meant for slight boosting / cutting adjustments while leaving the other frequencies alone.  

mind2069
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21 Jan 2015

I know in the end its the sound that matters but does setting low self gain to -12db on mclass sort of simulates a 12 db/oct LPF (considering they both have the same Q) I know they wont sound exactly the same cause every filter has its own personnality

Out of curiosity, just looking for the 12 db/oct meaning on a filter and if an eq can "simulate it" with the gain knob.

Heater
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21 Jan 2015

If you need a low pass filter why not just use a ECF-42?

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rcbuse
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21 Jan 2015

mind2069 wrote:I know in the end its the sound that matters but does setting low self gain to -12db on mclass sort of simulates a 12 db/oct LPF (considering they both have the same Q) I know they wont sound exactly the same cause every filter has its own personnality

Out of curiosity, just looking for the 12 db/oct meaning on a filter and if an eq can "simulate it" with the gain knob.
Setting the low shelf gain to -12db isn't the same as saying a filter has 12db/oct rolloff, and there is really no easy way to achieve that.  Could you dial in the MClass EQ to achieve the same effect as a traditional 12db/oct lowpass filter? Yes.  But you are going to need to work out the mapping of gain vs Q to achieve 12db/oct, and probably need to chain a few of them together to get the rolloff to continue at 12db/oct.

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QVprod
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21 Jan 2015

The Stereo imager is a much better low pass filter than the MClass EQ. Just solo the Lo Band.

mind2069
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21 Jan 2015

Heater wrote:If you need a low pass filter why not just use a ECF-42?
Cause the mclass is very cpu efficient, its when I need a lot of them, I will look into the stereo imager, I guess its pretty cpu efficient

Thanks for the replys

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rcbuse
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21 Jan 2015

Heater wrote:If you need a low pass filter why not just use a ECF-42?
mind2069 wrote:
Cause the mclass is very cpu efficient, its when I need a lot of them, I will look into the stereo imager, I guess its pretty cpu efficient

Thanks for the replys
Why do you think the MClass EQ is more efficient than the ECF-42?  They are probably both equal in CPU requirements with the EQ having one filter enabled.  If you used multiple filters on the MClass EQ, it would probably require more DSP than the ECF-42.



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Djstarski
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22 Jan 2015

QVprod wrote:The Stereo imager is a much better low pass filter than the MClass EQ. Just solo the Lo Band.
i agree with you their . if your going the M-Class route for filters the imager is the best choice . 

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selig
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22 Jan 2015

QVprod wrote:The Stereo imager is a much better low pass filter than the MClass EQ. Just solo the Lo Band.
Djstarski wrote:
i agree with you their . if your going the M-Class route for filters the imager is the best choice . 
And if you need resonance or other filter types, the ECF-42.
:)
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orthodox
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22 Jan 2015

I don't think MClass filters are any better or faster than ECF and PEQ.
Stereo Imager filters are close to LP12 and HP6 but crooked.

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tumar
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24 Jan 2015

Heater wrote:If you need a low pass filter why not just use a ECF-42?
Or Thor filters (like Low Pass Ladder Filter) via Audio Input 3?


Heater
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24 Jan 2015

Heater wrote:If you need a low pass filter why not just use a ECF-42?
tumar wrote:
Or Thor filters (like Low Pass Ladder Filter) via Audio Input 3?
I do that.  It's also got a nice high pass filter which is pretty good in an audio chain.

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selig
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24 Jan 2015

orthodox wrote:I don't think MClass filters are any better or faster than ECF and PEQ. Stereo Imager filters are close to LP12 and HP6 but crooked.
That's due to them being a complementary set, which is required for a crossover so they will reconstruct properly. 
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selig
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24 Jan 2015

Heater wrote:If you need a low pass filter why not just use a ECF-42?
tumar wrote:
Or Thor filters (like Low Pass Ladder Filter) via Audio Input 3?
Heater wrote:
I do that.  It's also got a nice high pass filter which is pretty good in an audio chain.
I've taken to using Pulveriser for HP filtering needs - a little easier than the Thor route (my previous MO). :)
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mind2069
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25 Jan 2015

Thanks for the replies

Well needing many of them in a combinator (each drum sound has and indivudual LP/HP) the ECF-42 would of been ideal also because of the size and cpu efficient but if does not have a HP, could of places one besides te other.

I will continue to use the D-Filter with no oversampling.

Question about kong filters, they coud work but they seem to color the sound, any one knows if the q can be set so the sound wont be colored,  just a simple HP / LP like SSL

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scifunk
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25 Jan 2015

As I understand it a 12db filter slope, means that the volume drops by 12db over the octave below the freq, in the case of a low pass filter. You can use the high cut on the MClass as a sort of Low Pass Filter. There are better options inc Pulveriser TBH. or get D-Filter which has changeable slopes and resonance.

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