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%

These drivers from KZ are poor sound quality. While CI is still reasonably good, ED and WBFK are weak.

a weekend five-minute modification to brighten and improve the sound for iems twice as much (by removing components :relaxed:)

RAU-34832-B148 Balanced Armature Supertweeter Knowles has advanced the state-of-the for in-ear acoustics with the release of its “supertweeter”. This new balanced armature offers much improved output with the ability to reach an ultra-high frequency of 40kHz, making it ideal for in-ear...

Off topic If you have sensitive skin, just working with uv resins and uv varnish and isopropanol is a constant battle with skin eczema. If you are sensitive of course. It's not that these products are safe for everyone, they are safe for the unsusceptible, sensitive people to skin diseases...

Bent or kinked tubing should not have a negative effect on the drivers as long as the diameter is maintained. The tube can be bent or flat but if there is a flow the sound measurement will be preserved. Silicone IEMS have a specific design with soft silicone tubing that are not rigid to keep...

freeze it in the freezer and crush

two options you can check, reverse RAB polarity and hi-pass ED with 2,2uF-220nF

Sonion 2354 probably 2354?

Only true black metal and soldering directly to the litz wire and floating them in the shell. :relaxed: Check old @piotrus-g reshell design

Here you have a simple implementation of a two-position DIP switch but series. Without leaving empty positions too.