[Ivan TT]

Bellsing 10013 impedances graphs:

1. Stock:

2. 25Ohm + 22uF Zobel:

 

[Ivan TT]

@Ivan TT Thank you so much for sharing. I am very happy you like the Bellsing 6, especially since I shamelessly advertised them here.

Worked well for me, much appreciated!

Could you compare them to your 4xRAB/4xRAF setups?

Yes, but I usually take some time to arrive at conclusions, since yesterday I have Bellsing 6 and 4xRAB with zobels so listening to both taking turns, what I CAN tell you is they have different signatures, but I like them both, no clear winner yet.

Also, just out of curiosity: Are you using unpolarized caps, or did you use polarized caps in series with reversed polarity?

Non-polar in Bellsing 6, polar 4.7uF tantalum in 4xRAB.
I don't think it really matters as polar caps are used for DC decoupling in many HP amps and DAPs, but please tell me more about that reverse polarity approach?

 

[eunice]

I don't think it really matters as polar caps are used for DC decoupling in many HP amps and DAPs, but please tell me more about that reverse polarity approach?

My knowledge of electronics is limited, but from what I know a polar cap has different behavior depending on the polarity of the voltage applied, which of course means they are not suited for AC. You can create an unpolarized cap from two identical polarized caps by connecting them in series in opposite polarity ( -||++||- or +||--||+ doesn't matter). The resulting capacitance is half of a single cap.

More detailed explanation in this post: https://www.eeweb.com/forum/polarized-vs-non-polarized-capacitors

 

[ForceMajeure]

Bellsing 10013 impedances graphs:

1. Stock:

2. 25Ohm + 22uF Zobel:

Awesome, Thanks!

 

[dhruvmeena96]

Bellsing 10013 impedances graphs:

1. Stock:

2. 25Ohm + 22uF Zobel:

That looks better than some flagships....
Damm, that's some flat impedance you got


Well, there was this article written by the creator of O2 amp. He said that BA iem are technically worse due to its bad impedance swings which caused different sound on different sorts of amp

But after zobel and @Ivan TT RC corrector for multi driver(since boucheret cell or zobel was made for single driver, so still thinking a cool name for his RC circuit) on multi driver, I think that statement is going to get wrong.

@Ivan TT well if you can build that for Bellsing by hit and trial, then it means, that if you are provided by impedance graph, you can make zobel for any driver by hit and trail

 

[DannyBouwhuis]

Hey guys,

I'd like to try a 4× RAF build I've been looking for some schematics on here but I couldn't find anything, can anyone give me some more info ?

Thx

 

[dhruvmeena96]

Hey guys,

I'd like to try a 4× RAF build I've been looking for some schematics on here but I couldn't find anything, can anyone give me some more info ?

Thx

which version are you trying to make

4x RAF series parallel + zobel

or

4x RAF Series + zobel

 

[DannyBouwhuis]

which version are you trying to make

4x RAF series parallel + zobel

or

4x RAF Series + zobel

Series parallel, I don't think I can drive series, and series parallel was better right ?

 

[dhruvmeena96]

Series parallel, I don't think I can drive series, and series parallel was better right ?

it depends
Well signature wise, series is way better(of charts)
Electrical and distortion point, parallel is better

for tubing you can make 2 RAF's drivers share the single tube and get dual bore design or make it like @Ivan TT (the resonator)

for zobel (series parallel)
Cz = 4.6uF
Rz = 41 ohms


for zobel (Series)
ask @Ivan TT
or
Cz = 1uF
Rz = 165 ohms




for wiring series parallel

Wire 2 drivers in series and make a pair of dual driver
then wire them in parallel

and you will have a quad driver assembly

you have to connect zobel to this quad assembly

take that speaker as quad assembly

if going series parallel

add a 30ohm series resistor to the positive leg in between your connection(mmcx or 2pin) and zobel

speaker -> zobel -> series resistor -> connection




by the way, its better to make 2 x RAF series

Cz = 2.2uF
Rz = 82 ohms

The bass quality and level is unmatched. its better than dynamic sony xb60ex in extension. So, the CI doesn't even hold candle....Not even HODVTEC. well, its linear style bass and doesnt have the amounts of any of the three driver, but it goes way deeper with immense control

distortion is way better than Standard BA and dynamics too

Soundstage will shock you

use dampers as per taste though

i use brown

 

[DannyBouwhuis]

it depends
Well signature wise, series is way better(of charts)
Electrical and distortion point, parallel is better

for tubing you can make 2 RAF's drivers share the single tube and get dual bore design or make it like @Ivan TT (the resonator)

for zobel (series parallel)
Cz = 4.6uF
Rz = 41 ohms


for zobel (Series)
ask @Ivan TT
or
Cz = 1uF
Rz = 165 ohms




for wiring series parallel

Wire 2 drivers in series and make a pair of dual driver
then wire them in parallel

and you will have a quad driver assembly

you have to connect zobel to this quad assembly

take that speaker as quad assembly

if going series parallel

add a 30ohm series resistor to the positive leg in between your connection(mmcx or 2pin) and zobel

speaker -> zobel -> series resistor -> connection

Thanks !! I think I get my drivers in next week then I can do some experimenting, can't wait. Thanks again

 

[DannyBouwhuis]

it depends
Well signature wise, series is way better(of charts)
Electrical and distortion point, parallel is better

for tubing you can make 2 RAF's drivers share the single tube and get dual bore design or make it like @Ivan TT (the resonator)

for zobel (series parallel)
Cz = 4.6uF
Rz = 41 ohms


for zobel (Series)
ask @Ivan TT
or
Cz = 1uF
Rz = 165 ohms




for wiring series parallel

Wire 2 drivers in series and make a pair of dual driver
then wire them in parallel

and you will have a quad driver assembly

you have to connect zobel to this quad assembly

take that speaker as quad assembly

if going series parallel

add a 30ohm series resistor to the positive leg in between your connection(mmcx or 2pin) and zobel

speaker -> zobel -> series resistor -> connection

Btw what's the purpose of the series resistor ??

 

[dhruvmeena96]

Thanks !! I think I get my drivers in next week then I can do some experimenting, can't wait. Thanks again

i updated my post////

the purpose of series resistor is to drop volume, have even linear distortion for extremely quick transition and attacks.

since we have sort of linear impedance, and zobel lowers the treble floor noise, this made the 1kHz noise and distortion seem more noticeable and we are sensitive to mids(@Ivan TT and one more guy once made this statement statement ). the 30ohms is sweet spot and it lowers the distortion and kills almost all noise to give a perfect black background.

with @Ivan TT tubing design you will have more soundstage

with my dual bore design, you can control the damping scheme of two tubes to tune peaks to the preferences


but i prefer 2x RAF series with zobel

 

[dhruvmeena96]

Well, MASM quad driver design I am going to share by today or tommorow

Inspired by MASM, one more RAB but with some new circuitry(not standard zobel)

Same DCR, flatter impedance
Quad driver, Quad component for Zobel and RAB load shifter, 1/4th distortion on paper(in theory, by predicting and calculating), dual bore

Since I have calculated it, I have to build it now

I will be sharing the design....no issue
Same GQ
Same RAB x 2(now its two)
Double resistor for impedance matching(its not L-pad or any derivative, you will see it )
Zobel circuit

 

[Xymordos]

So I just tested dhruvmeena96's 4xRAB design. I used 4x RAB32063 in a series-parallel configuration with a zobel of 5uf + 38ohms, with a series resistor of 30ohms. Measurements are below. Impedance is much flatter, and phase is flat too! Frequency response is measured through a 3mm diameter by 15mm length tube. Though I'm still waiting for my universal shells to arrive so I can't finish building them yet. Just by listening to the drivers, they sounded very clear and had great bass slam (though it was a very poor seal due to the lack of proper shells). Hope to listen to more of this when my shells and filters arrive.

Spoiler: Impedance Chart

Spoiler: Frequency Response - The one in green, ignore the other ones.

 

[ChrisJensen]

Hey, wanted to build my own CIEM, and was wondering if there was a driver setup I could buy off the shelf that is as good as westones w40 or Shure SE535s. Anyone has any recommendations for drivers? I listen mostly to acoustic and classical music