Topic: Help with equalizer

Hi All,
i do apologize if the thing has been asked before, but i'm having hard times searching for it.
I'm quite confused by the parametric EQ settings.

I own a beautiful pair of ElctroVoice interface D, those were originally equipped with an extenal Equalizer, i did not posses.
Apart from other possible regualtions, there were 2 fundamental settings implemented by default with the EQ in order to respec T/S parameters of the project.

1-28hz sharp cutoff (to rpotect woofers at high levels)
2-32hz boost of 6db.

What i've done is to:

1-Set band 1 to 28hz value, and apply a 12db reduction
2-Set band 2 to 32hz value and apply 32db boost.


The graph look like this:

https://i.ibb.co/8Y7RrJZ/j3-EWVLZ-QNCLlbk9ffd-R7-A.jpg


is it correct in your opinion or there's a better way to reproduce the original external crossover settings in your opinion?
Thank you so much in advance.

2

Re: Help with equalizer

I don't know the original filter, but your version does not offer much sub-filtering. Try this:

B1 G 0.0 F 20 Q0.8 Highpass
B2 G+10 F 30 Q 0.8 Peak
B3 G -12 F 20 Q 1.5 Peak

and see the difference on the left side at the border.

Regards
Matthias Carstens
RME

3 (edited by KaiS 2021-01-16 18:06:52)

Re: Help with equalizer

EasyRider82 wrote:

I own a beautiful pair of ElctroVoice interface D, those were originally equipped with an extenal Equalizer, i did not posses.
...
is it correct in your opinion or there's a better way to reproduce the original external crossover settings in your opinion?
Thank you so much in advance.

I have the original Electro-Voice EQ.

Based on my own measurements (1) I can emulate the Electro-Voice EQ with the following settings with a precision of 0.1 dB down to 16 Hz:

ADI-2 EQ Band1:
Gain: 0 dB, value doesn’t matter (2)
F: 32 Hz
Q: 1.8
Shape: High Pass

That’s all, seems that’s what Electro-Voice built into their equalizer, a hi-Q (= resonant) High Pass Filter.


(1) Measurements where done with calibrated system, AudioTools by Andrew Smith.

(2) When using the High Pass Filter the gain has no effect on the curve.

Re: Help with equalizer

KaiS wrote:
EasyRider82 wrote:

I own a beautiful pair of ElctroVoice interface D, those were originally equipped with an extenal Equalizer, i did not posses.
...
is it correct in your opinion or there's a better way to reproduce the original external crossover settings in your opinion?
Thank you so much in advance.

I have the original Electro-Voice EQ.

Based on my own measurements (1) I can emulate the Electro-Voice EQ with the following settings with a precision of 0.1 dB down to 16 Hz:

ADI-2 EQ Band1:
Gain: 0 dB, value doesn’t matter (2)
F: 32 Hz
Q: 1.8
Shape: High Pass

That’s all, seems that’s what Electro-Voice built into their equalizer, a hi-Q (= resonant) High Pass Filter.


(1) Measurements where done with calibrated system, AudioTools by Andrew Smith.

(2) When using the High Pass Filter the gain has no effect on the curve.

Wow! thank you so much for this, can't expect any better! smile
So if i've done right it should look like this, right?

https://i.ibb.co/8ggJFkb/20210116-172757.jpg

Thank you again!

Re: Help with equalizer

That’s correct!

Re: Help with equalizer

KaiS wrote:

That’s correct!

Thank you again! Do you have those interface D?
like them so much!

Re: Help with equalizer

I do have also the first interface A with the original equalizer, I repaired recently,  I measured the output with an oscilloscope and will replicate that too in the awesome RME dac!

I'm better with oscilloscope than eq

8 (edited by KaiS 2021-01-17 01:20:52)

Re: Help with equalizer

As far as I know these Electro-Voice Equalizers all have the same frequency response!

At least the Sentry 3 and Interface-(α,β) series the same EQ was offered.

Some had individual labels, like the newer one for the Interface β, but internally still the same.


If you can give numerical values for spot frequencies I can check if your’s is the same.

Re: Help with equalizer

I've done some research recently and some eq are interchangeable with others but not all. I've found all specs(official electrovoice papers) and confirmed with interface A measurements, where the boost is at 35hz and cutoff at 32hz.

Not that I'll be able to discern between those, but they're a little different.

Thank you again for your precious help!



KaiS wrote:

As far as I know these Electro-Voice Equalizers all have the same frequency response!

At least the Sentry 3 and Interface-(a) series the same EQ was offered.

Some had individual labels.

10 (edited by KaiS 2021-01-17 01:27:36)

Re: Help with equalizer

Maybe they changed this later, from the start the same EQ was offered for Sentry 3 and Interface α.

I have an Interface β EQ that is still exactly identical, but offers 2 tape outputs at the back, hardwired parallel, and a more modern black faceplate.