Passive EQ - Where are the Hi-Mid controls?

[freddiphin]

I don't quite get this. The PassiveEQ claims to have Hi-Mid controls that are clearly not there. Or better said, not clearly there.
Exactly what knobs are what?? Only "Low Frequency" and "High Frequency" are unambiguous.
I find that the "Bandwidth" seems to be a single Q for both the Low and High bands. This is all I require with this particular plugin, but why all the talk of the non-existent "Hi-Mid" and non-explaining of the single Bandwidth? A manual misalignment issue, no doubt.

(I have to say, I just got into an -almost- argument with the Studio Assistant which kept insisting that the Hi-Mid controls are indeed there and that I was obviously not looking at the Passive EQ module. The cocky s.o.b. ! )

 

[Wolfger]

The Bandwidth, Boost and High-Frequency Control belong together, it‘s a Bell-Filter with selectable frequency from 3000–16000 hz, where you only can boost and select the bandwidth of the bell. The description as high-mid frequency is misleading and doesnt reflect the labelling. The attenuation and attenuation-selection belong together. It’s a high-shelf which only can attenuate with selectable frequency 5-10-20 kHz.

 

[Wolfger]

A nice read about the pultec:

https://analogvibes.com/wp-content/uploads/tube-program-equalizer-3-bands-of-glory-analogvibes.pdf

 

[freddiphin]

The Bandwidth, Boost and High-Frequency Control belong together, it‘s a Bell-Filter with selectable frequency from 3000–16000 hz, where you only can boost and select the bandwidth of the bell. The description as high-mid frequency is misleading and doesnt reflect the labelling. The attenuation and attenuation-selection belong together. It’s a high-shelf which only can attenuate with selectable frequency 5-10-20 kHz.

Got it. I thought the Bandwidth was a single Q applied to both Low and High given its positioning, but now I see/hear. The manual is just dead wrong with the entries that have "Hi-Mid" at the start of the line. And visually it's not entirely clear, but I see that it was Pultec's design choice. Thanks for that link!

 

[lokeyfly]

The Pultec Passive EQ has had this somewhat vague architecture, and has this overlapping, yet also non clear handling of EQ curves.

The EQP-1 is a passive equalizer with a tube amplifier stage that restores the gain lost from the EQ. Its low frequency section is a shelving filter with selectable frequency bands at 30, 60, and 100 Hz, which can be simultaneously boosted or attenuated. The tube amp stage was for practical use in broadcast and recording back in its heyday.
So avoid looking at its controls in any linear EQ view. The bell curves between the two are not so clear, but can provide very nice contours - at times.
What you can do is use a Plugin Doctor [by DDMF] and view curves if you choose to. Once you see those differences, you'll get the drift. The boost/cut diagram in Wolfger's link displays that duck-like curve. Of course that curve alters tremendously depending on shelved EQ selection, bandwidth, boost & attenuation. So the Plugin Doctor is really pretty nifty from a purely analytic sense.

I'd then suggest, weather you purchase the Plugin Doctor or not, to simply use your ears only. Of course the Plugin Doctor will make these curves visually clear to you.... or ehr ... your cocky sob studio assistant. Since they're questioning this. Get them to pay for the PD.