GlissEQ vs. Electri-Q

[Aleksey Vaneev]

martian, that looks more like a Butterworth filter. You may try 'Btworth' option in Elephant - it should provide something very similar (it is a -36dB/oct high-pass filter).

[martian]

added gliss 24db to previous.

[martian]

martian, that looks more like a Butterworth filter. You may try 'Btworth' option in Elephant - it should provide something very similar (it is a -36dB/oct high-pass filter).

ok, didnt realise butterworh had the 'hump' since gliss doesnt (?)

anyway, this filter is reqired as a mix tool, i own elephant but it doesnt go beyond 40hz.

[Aleksey Vaneev]

GlissEQ has this 'hump', but it adds DC removal filter as well, so this 'hump' is not as clear as it is on RenEQ group delay plot.

So, you can almost safely use GlissEQ's cut filter for a similar performance.

[martian]

i can see the effect of the dc filter, and im refering to the 'hump' in stop band freq response btw.

the group delay is always more with gliss 24db slope than ren even at max slope (36db?!), and they sound different when both at 24db, waves is tighter, less ringing.


[realisation of misunderstanding and edited. ]

[fgimian]

I'd love to see how the Sonalksis EQ compared here. I personally think it's one of the best out there.

Note to developers, check out the high & low shelving filters in Sonalksis, be sure to turn off Constant Q and try boosting and cutting. This is where Sonalksis shines big-time, it is a resonant high shelf filter which adapts itself properly when you cut and boost, the REQ and GEQ also have a resonant high shelf filter but when you cut, they maintain the same shape which sounds completely unmusical and usually results in me having to change Q values. I'll post some frequency responses this afternoon.

Fots

[Aleksey Vaneev]

i can see the effect of the dc filter, and im refering to the 'hump' in stop band freq response btw.

the group delay is always more with gliss 24db slope than ren even at max slope (36db?!), and they sound different when both at 24db, waves is tighter, less ringing.


[realisation of misunderstanding and edited. ]

RenEQ does not have constant 36 dB/oct below cutoff - it 'rounds' a bit, so it does not have a bigger hump.

As I've said, GlissEQ has 1st order DC filtering going on and that's why its group delay is a bit higher overall. Hump of its high-pass filter is not much higher than that of RenEQ (given the constant roll-off). You may adjust GlissEQ filter's bandwidth to make hump a bit smaller. Please also note that this hump is moved a bit to the left in comparison to RenEQ. To sum up, to match these filters you'll need to adjust bandwith and move center frequency to the right a bit (in GlissEQ).

EDIT: anyway, you can't match these filters perfectly as 36 dB/oct roll-off is unattainable with 24 dB/oct filter.

[martian]

sorry, this is still making little sense to me.

i know ren eq doesnt have the consistant freq roll off, at around -35db on the stop band it has the start of the 'hump' (defintion of my 'hump': the region between 10 and 30hz on waves ren freq response plot). i thought this 'compromise' in freq response would be responsible for the tighter group delay.

now the group delay 'hump'. i can see its over to the left with gliss, and i know reducing the filter slope makes the hump smaller, and so rings less, like reducing bandwidth of any bell/shelf/etc filter. but with gliss the group delay never gets anywhere near as small as waves ren when they have the same cutoff slope (ignoring waves freq response hump). this must the reason waves ren sounds tighter and better to me on kick drums, no? finally, i cant see how such a small delay from the gliss dc filter can account for this difference?

damn, now i cant get black eyed peas out my head.

[Christian Budde]

I'd love to see how the Sonalksis EQ compared here. I personally think it's one of the best out there.

Just downloaded the demo 17MB! It doesn't have something special though (from a scientific perspective). The shelving filter types are completely matchable with Electri-Q and as far as I remember Gliss-EQ has the same (basically I know of three different types). It also has up to 24dB/Oct filters and a nice Orfanidis peak EQ (to make the bell kind of symmetrical). However as Aleksey quoted with a single biquad you may come close, but you can't match it exactly.

Christian

[martian]

Just downloaded the demo 17MB!

yes they force you to download their entire product line and all versions at once .

It doesn't have something special though (from a scientific perspective). The shelving filter types are completely matchable with Electri-Q and as far as I remember Gliss-EQ has the same (basically I know of three different types). It also has up to 24dB/Oct filters and a nice Orfanidis peak EQ (to make the bell kind of symmetrical). However as Aleksey quoted with a single biquad you may come close, but you can't match it exactly.

out of interest do you know what the bell in sx Q is then, if its not orfanidis?

[4damind]

I'd love to see how the Sonalksis EQ compared here. I personally think it's one of the best out there.

Not really Its a good EQ but its replaceable. For cutting and boosting I have better results with GlissEQ and the dynamic feature or with the Hydratone from Tritone Digital. The EQ from Sonalksis is the only plugin from Sonalksis which is IMHO not a "must have" and where you find many competitors.

[Aleksey Vaneev]

finally, i cant see how such a small delay from the gliss dc filter can account for this difference?

If you have noticed already, this group delay from DC filter is mostly centralized around frequencies below 40 Hz while this can't be objectively heard in most cases. So, I guess this 'sound behaviour' is all about the shape of the cut filter. Moreover, steeper 36 dB/oct filter may sound 'smoother' because it does not have lower frequencies that you want to treat as unimportant as much as in 24 dB/oct filter. So, it should sound 'cleaner' in this sense. Probably if you move to comparing 24 dB/oct filters in both cases, many 'oddities' will go away (of course, you will have to match Q and center frequency of filters in RenEQ and GlissEQ).

By 'hump' I meant bell-shaped increase in group delay around center frequency.

As for that SX bell curve, it does look like Orfanidis (and it is not symmetric of course - its right lobe is a bit more S-curved than it should be as in an ideal case).

[martian]

If you have noticed already, this group delay from DC filter is mostly centralized around frequencies below 40 Hz while this can't be objectively heard in most cases. So, I guess this 'sound behaviour' is all about the shape of the cut filter. Moreover, steeper 36 dB/oct filter may sound 'smoother' because it does not have lower frequencies that you want to treat as unimportant as much as in 24 dB/oct filter. So, it should sound 'cleaner' in this sense. Probably if you move to comparing 24 dB/oct filters in both cases, many 'oddities' will go away (of course, you will have to match Q and center frequency of filters in RenEQ and GlissEQ).

By 'hump' I meant bell-shaped increase in group delay around center frequency.

yes i thought a few posts back we were refering to different humps, unless otherwise specified i meant the freq response hump below 40hz in waves graph.

as you say the difference in sound must be the filter shape (and resulting group delay) since i cant see how the dc filter would be audible to me. also i have checked with blocc hipass which has no dc filter.

anyway, i think the confusion is still there because i choose 36db with waves and 24db with gliss. but this was just to demonstrate waves ren has less delay even at 36db compared to butterworth at 24db. when comparing by ear i of course try to set them to the same 24db slope to at least -25db, after which waves freq response hump then comes in. waves sounds a bit tighter to me, and i guess this is explained by the difference in group delay which grows when they both have the same slope. for instance with both doing 24db slope -3 at 60hz, there is a difference of 100 samples delay at 55hz, waves ren being the shorter.

maybe i am hearing things and this difference is considered negligible? but i got it right with short kick drum in a well bass trapped room and some blind A/Bs, will test better later though. it is v difficult to exactly match their freq responses so that may be influencing me still.

As for that SX bell curve, it does look like Orfanidis (and it is not symmetric of course - its right lobe is a bit more S-curved than it should be as in an ideal case).

the only reason i thought different is becuase i can match it closer to aireq's high freq bell than electri-q orfanidis and waves ren (which i believe is also orfanidis). but i guess the 's' shaping just before nyquist is still the same trait.

thanks aleksey for all your input anyway!

[Aleksey Vaneev]

I've checked out these filters again. It seems that while GlissEQ uses an decent approximation of Butterworth filter, RenEQ may use Linkwitz-Riley filter. These are different, and have a bit different group delay. In reality DC filter I use hardly adds any group delay. So, I have mistaken, and it was the group delay of the whole GlissEQ's high-pass filter.

Here is a picture of GlissEQ's filter configured as Linkwitz-Riley filter @ 60 Hz.

http://www.voxengo.com/temp/lriley_groupdelay_60hz.png
(temp file - will be removed later)

As for your mention of 'tighter' sound, I think this is not universal. In your case it is tighter, in case of another person and another sound source, it won't be as tight. There is no universal solution, because sound sources may have different spectral and phase content and so, may result in a different subjective coloration when the same filter applied.

[Aleksey Vaneev]

This is the picture of Butterworth -24dB/oct of GlissEQ:

http://www.voxengo.com/temp/bworth_groupdelay_60hz.png

EDITED.