The effect you have obtained causes an enlargement of the pressure flow in front of the driver, this can be achieved in the same way if you use a larger tube, such as 2mm instead of 1.5mm or 1mm. On the same rule if you need a vent 2mm (3.14mm2), you can make a vent 1mmx3.14mm etc

asap RAU from Soundlink. They have RAD in stock too.

Today I'll finally know if I'm saying goodbye to WBFK :slight_smile:

Is it a bent copper tube? Nice steampunk vibe :sunglasses:

BIG boys :beyersmile:

6BA (5way) + 7BA (6way)

Right! Looks drilled. Interesting story.

I have a project with BACK open vented DTEC, worried about overdrives and cracking sound but managed to vent them without a problem. I also saw a commercial IEM open BACK DTEC somewhere.

External SMD tuning to have more fun :relaxed:

Very good choice. Ci is one of the most powerful woofers. TWFK smooth mids and high quality top.

20mm red damper Knowles CI22955 x2 one full range, second 10ohm resistor, Sonion 2389 half coil wiring 1,5uF green damper 12-14mm *this is not a scheme UE7 legally protected, this is my homage wiring proposal

Silicone ciems. Clear canals, colored shells.

Unfortunately there is no documentation on google indexed, you would have to ask the knowles for the data sheet. For sure 33649 is without spout and the construction of this wbfk is identical to the ue18+ It's hard to buy, you should have to get the minimum 25*palette through some distributor...

top firing WBFK-33649, difficult to buy during the Chinese lockdown and in single quantities :(

They are marked "KZ" brand. For example ED/WBFK: Knowles is 100%/100% sound quality Bellsing is 70%/50% KZ is 50%/30%