Yes, and impedance at the specific frequency, not the DC value, unless you are dealing with Planar or DD where Z=Rdc for 99% cases. No In most cases the R is not necessary. You need to consider electrical phase of the driver and how it fits into the rest of the design, in most of the cases...

Lol, you think I'm doing any math haha, use online calculators, you just have to know impedance plot of the driver, which you could technically measure yourself. Yeah of course you can do that, just again be mindful of the crossover frequency - in that configuration 6-8kHz could be a sweet-spot...

You need to do some calculations to understand where you are first, otherwise you are going in blind. 22uF 2389 (single, no center cap) gives you cut off fr at 830Hz with center tap that becomes roughly 1.6kHz ( in reality probably closer to 1kHz as the impedance rises and is not linear) 2.2uF...

Lose the center tap - connect normally - this will give you more mids as your crossover will move an octave down. 2389 is already very low impedance, in parallel dual that impedance is halved further with center tap that impedance is halved once again, you are looking at 2.5 ohms at 500Hz if my...

In this config, if the black squares are caps, the top driver is connected with a 2nd order crossover (12dB/oct), this might not be the most optimal unless the goal is to boost only the highest frequencies in a narrow range

LOL thanks for believing in me

clearly there's sound leak, you just have to find where.

From what I see you have a front-volume vent going to the top, this is why you got no bass, you need to partially block the vent with damper and vent the back volume of the DD at the same time

Glad you like our Hybrid 3Pro :)

Thank you Marcus for a wonderful review! Whaaaat! hahaha! That's AMAZING guys!

Actually HeadphoneCompany should have FIBAE 7U demo, reach out to Thomas. They don't list 7U on the website but do have a demo.

https://eu.mouser.com/ProductDetail/Knowles/RDI-33438-000?qs=BJlw7L4Cy79a%252BXw%2FeRvFfw%3D%3D https://www.digikey.com/en/products/filter/speakers/156?s=N4IgjCBcoLQCxVAYygMwIYBsDOBTANCAG4B2aWehA9lANohxwDsATAJwgC6hADgC5QQIAL6igA

In my personal opinion, here's the thing, Knowles is a huge company (700M$ reported revenue for 2023, 1.4B$ in assets LINK) and funnily enough I think Balanced Armatures are their smallest share of profits. They moved to automated lines such as whole new R-series (RAU, RAN, RDI, and many many...

It could be an artifact form the sound card. In general anything below 20Hz you can disregard.

That because the vent releases pressure in the opposite phase. You are feeding the inverted phase signal into positive signal canceling portion of frequency, obviously the result is lower SPL and added distortion. I understand you want concept similar to transmission line in speakers, but...