Based on the explanation, it seems that maybe the design is such that unlike standard gates where normally the input level remains the same and the threshold varies, in this case the threshold remains the same, while the input signal is attenuated compared to it. I have no idea if that's the way it's designed, but if so, it would justify the way it's calibrated (although even then, it would be more logical if the control's "sense" was reversed). At least he agrees it's unconventional. It would probably make more sense if the calibration just went from 1 to 10, with "1" meaning less gating or expansion, and "10" meaning more gating or expansion.
 
This reminds me of the attack control on synthesizers. I consider the attack control as determining how slow the attack is, so turning up the attack control increases the amount of attack time. Right? But I've run into synthesizers where the control sense is reversed. When I asked one designer why, he said that the attack time determines the speed of the attack, so therefore turning it up should make the attack faster and reduce the attack time.

Before some of you may suspect  that I wonna bash Nomad factory products ,
I have to admit that I use and like many of there products such as echoes and magnetic 2 a lot.
 
The gate let´s  at 0db some signals pass through equally to the
Nomad Brickwall limiter BW 25 which lets at 9 db overload signals pass through.
 
This is known for some years in different forums and audio books such as
"Internal mixing" aso.
regards

Anderton
Based on the explanation, it seems that maybe the design is such that unlike standard gates where normally the input level remains the same and the threshold varies, in this case the threshold remains the same, while the input signal is attenuated compared to it. I have no idea if that's the way it's designed, but if so, it would justify the way it's calibrated (although even then, it would be more logical if the control's "sense" was reversed). At least he agrees it's unconventional. It would probably make more sense if the calibration just went from 1 top 10, with "1" meaning less gating or expansion, and "10" meaning more gating or expansion.
 
This reminds me of the attack control on synthesizers. I consider the attack control as determining how slow the attack is, so turning up the attack control increases the amount of attack time. Right? But I've run into synthesizers where the control sense is reversed. When I asked one designer why, he said that the attack time determines the speed of the attack, so therefore turning it up should make the attack faster and reduce the attack time.

I know this is sidetracking but from a synthesizer UI POV that is completely ridiculous. Do you remember which synth that was? I've never encountered one that was built that way.

I do have a compressor that lowers the threshold as you turn the knob clockwise so you get "more compression" (TL Audio Ivory II 5051). Which I also find quirky. They should have labelled the knob "compression" then instead of "threshold".

I'm trying to understand the concept you're describing.  So in most gates, you can adjust the threshold and the input level is what it is.  Anything from the input signal that doesn't exceed the threshold is attenuated.  
 
In the concept you're describing, are you suggesting that in reality the threshold is static and adjusting the threshold parameter is actually attenuating/increasing the input signal???  If not could you further explain?
 
O.k. this is an interesting concept.  Let's explore it (if this is what you're suggesting).  Going back to my example in the video, if my input signal is a 1kHz sine wave with an amplitude of -12dB.  With this new idea of a threshold parameter, why would setting the threshold to 0dB create a situation that leaves the gate sounding like it's wide open, instead of the conventional sound of it being closed?  Vise versa for the threshold setting of -70dB having the same effect as closing the gate in conventional gates.  To add on top of that, why is the point at which the gate opens and closes at approx. -58dB? I say approx. -58dB because it was difficult to pin down the exact value due to the precision of the control.  What would the internal threshold level have to be to require the input signal to be lowered -58dB to reach the "line" that the gate opens and closes?  
 
Simple math puts the input signal now at approx. -70dB after applying 58dB of attenuation.  Seeing that the lowest value on the threshold control is -70dB, does this suggest that -70dB is the magic number?  So in other words the input signal is attenuated down the amount displayed in the threshold control until the parts you don't want to hear are below -70dB?  Thus closing the gate for anything under -70dB internally.
 
Granted this could work, but it is the most unintuitive approach I have ever seen.  If this is the way it works, calling the control the "Threshold" is a misnomer.  It's a bit misleading.
 
I know I said I'd move on, but this is pretty interesting to me and I'd like to give the developer the benefit of the doubt considering the other plugins in the Blue Tubes Series are wonderful.
 
Ah well...
 
 

Sanderxpander
I know this is sidetracking but from a synthesizer UI POV that is completely ridiculous. Do you remember which synth that was? I've never encountered one that was built that way.

The designer I talked to had one of those boutique synths (analog) at the Superbooth in Frankfurt, many years ago...sorry, I don't recall who made it. I thought maybe he accidentally wired the pot in reverse just before the show  

LittleStudios
I'm trying to understand the concept you're describing.  So in most gates, you can adjust the threshold and the input level is what it is.  Anything from the input signal that doesn't exceed the threshold is attenuated.  
 
In the concept you're describing, are you suggesting that in reality the threshold is static and adjusting the threshold parameter is actually attenuating/increasing the input signal???

I'm not suggesting it's reality, it's how I interpreted what the engineer said about "The input signal is an approximate dB above the lowered/lower Threshold level." I have no clue if that's how it's designed internally...I just turn the control until I don't hear the things I don't want to hear. I lead a simple life  

It was arrogant of me to assume that because I may not understand the nature of this plugin's Threshold control that it must be a bug or poor design.
 
Now on the other hand I'd prefer it if the Threshold control behaved more like conventional expander gates.
 
Ok I feel better 

Anderton
...This reminds me of the attack control on synthesizers. I consider the attack control as determining how slow the attack is, so turning up the attack control increases the amount of attack time. Right? But I've run into synthesizers where the control sense is reversed. When I asked one designer why, he said that the attack time determines the speed of the attack, so therefore turning it up should make the attack faster and reduce the attack time.

 
The SPL Transient Designer works that way. I guess it makes sense in this case because the centre position represents the unaffected signal and turning it "higher" boosts the transients and turning it "lower" reduces them. It still feels wrong to me though.

I can understand it from a transient designer or a compressor because they are not quite as standardized as a class, but on a subtractive style synth with traditional ADSRs it's nuts. It's like someone wiring the volume pot in reverse. You can design it any way you want of course but if you're going to do that in an environment where the accepted standard is the opposite you're just going to tick off everyone who wants to use your product.

Maybe by "Expander Gate" they meant they are trying to expand your concept of how a gate can work??