[dhruvmeena96]

Dont go with the numbering(like 66 etc) those are reference number in research paper.

See the formula below
RW = resistance DCR of woofer
Rt = resistance DCR of tweeter


Resistor is on positive leg
Inductor on negative leg

Try to keep capacitance of crossover, RW and Rt as small as you can

So that you can find the inductive value.


I took the zobelled RAB and was trying to use an ED29689 as tweeter with 470nF capacitor

Which give RW = 22 ohms
Rt = 3.65 ohms
C = 0.47uF

Well this can be used on bellsing 6 to lower bass and mids to treble nearby level if we are able to find something while doing hit and trial.

I will try doing it.

I have to make DTEC impedance be equal to TWFK in bellsing6

So I get overall 8ohm impedance flat.

Then I am thinking of adding series resistor of 20ohms.

That will make sense

 

[Caluub]

RAB32257 update(RAB32063 was discarded because I was not getting bass depth and oomph, thanks to @Choy Wei De )


Resonator(shifted near horn, for less tube effect)

1.2mm ID 2mm OD(6.5mm length from spout)
2.0mm ID 3mm OD(1.0mm length, Resonator, Buffer Mouth for horn)
1.2mm ID 2mm OD(2.5mm length)





Horn

2.0mm ID 3mm OD(2.5mm length) -> White Damper
3.0mm ID 4mm OD(3mm length)


Zobel circuit

Cz = 4.6uF
Rz = 41ohms


Series resistor

https://www.digikey.be/product-deta...up/Y116920R0000B0R/Y116920R0000B0R-ND/4226529

This resistor....20ohms




Flagship sound
End of RAB perfection

Does anyone know a supplier for the 1.2mm/2mm and 2mm/3mm tubings used here?

 

[dhruvmeena96]

Does anyone know a supplier for the 1.2mm/2mm and 2mm/3mm tubings used here?

https://www.amazon.com/SMC-Polyurethane-Metric-Tubing/dp/B004N84MTA

1.2mm ID/ 2mm OD

Other are common

 

[Caluub]

https://www.amazon.com/SMC-Polyurethane-Metric-Tubing/dp/B004N84MTA

1.2mm ID/ 2mm OD

Other are common

Thank you. It seems like I will have to buy an enormous length of tubing to get the 1.2mm ID. Do you think it would be okay to just use 1mm ID/2mm OD instead?

 

[dhruvmeena96]

It would be hassle to fit on the spout of BA
Your choice

It would require some pressure

Plus tuning would be a little bassy too

Thank you. It seems like I will have to buy an enormous length of tubing to get the 1.2mm ID. Do you think it would be okay to just use 1mm ID/2mm OD instead?

 

[Ivan TT]

Does anyone know a supplier for the 1.2mm/2mm and 2mm/3mm tubings used here?

Soundlink: PVC Tubing Tube for IEM BTE Hearing Aid Earmold Earmould DIY In-ear Monitor Driver Damper 1.0 mm ID, 1.5mm ID, 2.0mm ID,
https://s.click.aliexpress.com/e/roM9NvI

 

[ThanosD]

I finally found some time, and assembled a pair of RAF-32873, with green dampers, using a pair of Etymotics style shell, which was so generously sent to me by @Ivan TT .

The technique of making a loop with the soldered wires and a bit of heat shrink worked like a charm


I have to say, they sound good. The bass doesn't sound as deep as Tin T2's, and I think it has more mid bass, but generally they sound good, especially for how much they actually cost. And the treble, might have a little less detail, but is very pleasant, and not piercing.



I have a question, is it possible to make a zobel circuit outside of the shell, at some part of the cable for example? I'd like to try it. The RAF-32873 has the same specifications with RAB-32257, at least according to soundlink.

 

[eunice]

https://www.amazon.com/SMC-Polyurethane-Metric-Tubing/dp/B004N84MTA

1.2mm ID/ 2mm OD

Other are common

World this one work too ? It’s silicone : https://www.amazon.de/dp/B07FBDTPX2/ref=cm_sw_r_cp_api_i_-0uYCbAWK6227

 

[eunice]

I have a question, is it possible to make a zobel circuit outside of the shell, at some part of the cable for example?

Yes, look for @Ivan TT Zobel test rig on a breadboard a few pages back.

 

[Ivan TT]

I have a question, is it possible to make a zobel circuit outside of the shell, at some part of the cable for example? I'd like to try it. The RAF-32873 has the same specifications with RAB-32257, at least according to soundlink.

Yes, look for @Ivan TT Zobel test rig on a breadboard a few pages back.

Provided you get SMD components it should be reasonably easy to mount them inside of a 3.5mm jack or socket housing, essentially creating short extension cable, similar to 2.5mm to 3.5mm adapters

Spoiler: Like this one:

https://www.aliexpress.com/item/FII...-2-5mm-balanced-output-cable/32890820615.html
Socket:
https://www.aliexpress.com/item/1pc...mm-3-pole-Stereo-Socket-Gold/32914555254.html
Jack:
https://www.aliexpress.com/store/pr...adphone-repairing-DIY/502420_32899702637.html

 

[Choy Wei De]

Does anyone know a supplier for the 1.2mm/2mm and 2mm/3mm tubings used here?

I used this
https://m.tb.cn/h.ecaRO0J?sm=5cbae5
I have used 1.0mm ID tube before. I didn’t use any glue for prototyping. 1.00mm ID always detached itself inside the shell. I changed to 1.2mm ID and it stay intact very well.

 

[dhruvmeena96]

I finally found some time, and assembled a pair of RAF-32873, with green dampers, using a pair of Etymotics style shell, which was so generously sent to me by @Ivan TT .

The technique of making a loop with the soldered wires and a bit of heat shrink worked like a charm


I have to say, they sound good. The bass doesn't sound as deep as Tin T2's, and I think it has more mid bass, but generally they sound good, especially for how much they actually cost. And the treble, might have a little less detail, but is very pleasant, and not piercing.



I have a question, is it possible to make a zobel circuit outside of the shell, at some part of the cable for example? I'd like to try it. The RAF-32873 has the same specifications with RAB-32257, at least according to soundlink.

You can make it inside the shell itself too.

Or can make inside the connector

 

[eunice]

Waiting for measurements and final answer in the future

1) Setup

Out: AudioQuest Dragonfly Black (USB DAC/AMP with 3.5mm out)
Driver: Knowles CI-22955
IN: MiniDSP UMIK-1 (Measurement microphone with USB)

2) Wiring

Ring of 3.5mm (R in the picture) to Terminal 2 POSITIVE on the CI.
Sleeve of 3.5mm (GND in the picture) to Terminal 1 NEGATIVE on the CI





3) I played a simple Kickdrum and recorded it back:



Since the attack phase is a little delayed, I matched the wave forms so the end is the same.

That way the polarity of recorded wave form looks identical to polarity of output waveform.

If these 3 assumptions are correct:

1) Swing up in .WAV file is converted to swing up in voltage on the 3.5mm output by the Dragonfly
2) Swing up in air pressure is converted to swing up in recorded WAV by the UMIK-1
3) Wiring of Dragonfly is correct

Then you should connect the + (center of mmcx) to the + of the driver and not the other way around.

But to be honest, I am not sure.
Audacity Project.zip

 

[eunice]

Clarity shootout:

Spoiler: Clarity Graph 4x RAB vs Bellsing 6 vs Bellsing 6 + Zobel vs Knowles GV

 

[Cevisi]

Clarity shootout:

Spoiler: Clarity Graph 4x RAB vs Bellsing 6 vs Bellsing 6 + Zobel vs Knowles GV

Whats better now