Genelec 8351B Teardown (2nd Disassembled)

[Pearljam5000]

I cried a little when I found out they are made out of paper(even though they are supposed to be durable as mentioned in this thread )
Psychologically it's hard to accept

 

[Hephaestus]

I cried a little when I found out they are made out of paper(even though they are supposed to be durable as mentioned in this thread )
Psychologically it's hard to accept

I hear you! But in reality these are reliable products and made to last decades

 

[Sebastiaan de Vries]

I cried a little when I found out they are made out of paper(even though they are supposed to be durable as mentioned in this thread )
Psychologically it's hard to accept

You cry more to hear that most likely the previous 8351A utilized a honeycomb flat cone design. I gathered that from the Genelec AES paper, page-7
The Acoustic Design of Minimum Diffraction Coaxial Loudspeakers with Integrated Waveguides

"System types A and B use a paper cone woofer while type C uses a honeycomb woofer design with stiff planar diaphragm"

The Acoustic Design of Minimum Diffraction Coaxial Loudspeakers with Integrated Waveguides

Jokes asides. Genelec uses paper cones in most of their woofer range, including all subwoofers. Mulitple coustic designers are generally agree that paper is the right material for bass transducers.

I can also testify that I found the bass response of the 8351B a vast improvement over the 8351A.

 

[YSC]

the port looked interesting as it seems the port duct is mostly cut open?

 

[More Dynamics Please]

Starting with the new IN-5 Kali Audio is in process of transitioning their speaker cones from poly-coated paper to plain paper.

 

[Pearljam5000]

 

[Ilkka Rissanen]

Maybe @Ilkka Rissanen would have something to say about the woofer tears though, if that's a cosmetic thing that isn't important, or actually a problem that shouldn't be there?

What does concern me a little bit is the tearing? of the woofer cones?

Hello,

Thanks for your eagle eyes! The highlighted part of the woofer diaphragm is a designed feature and should look exactly like that. So, nothing to be worried about!

 

[Sebastiaan de Vries]

Hello,

Thanks for your eagle eyes! The highlighted part of the woofer diaphragm is a designed feature and should look exactly like that. So, nothing to be worried about!

Thank you Ilkka.

 

[preload]

Hello,

Thanks for your eagle eyes! The highlighted part of the woofer diaphragm is a designed feature and should look exactly like that. So, nothing to be worried about.

Hi @Ilkka Rissanen, it is great that you're here on ASR! Would you be able to speak to the rationale/benefit for using paper as the cone material on the 8351B woofers?

 

[mkawa]

i've heard them and they are ridiculously detailed, hit low bass easily i wish i had known about them before i changed out my living room system a year and a half ago. i have 8040bs and love them, but can easily tell the difference in an A/B

I am impressed that such a modest looking interior can produce that sound. i live a couple miles from the US HQ of genelec and was lucky enough to try a variety of models before i settled on the 8040s. i am curious, @Ilkka Rissanen if you work with the subwoofer design at all?

 

[Ilkka Rissanen]

i've heard them and they are ridiculously detailed, hit low bass easily i wish i had known about them before i changed out my living room system a year and a half ago. i have 8040bs and love them, but can easily tell the difference in an A/B

I am impressed that such a modest looking interior can produce that sound. i live a couple miles from the US HQ of genelec and was lucky enough to try a variety of models before i settled on the 8040s. i am curious, @Ilkka Rissanen if you work with the subwoofer design at all?

If you are familiar with my background/history, you know that subwoofers and low frequencies are very close to my heart! I have worked as a project and design lead for many of our subwoofers, ranging from the smallest 7040A to the largest 7382A.

 

[Sebastiaan de Vries]

If you are familiar with my background/history, you know that subwoofers and low frequencies are very close to my heart! I have worked as a project and design lead for many of our subwoofers, ranging from the smallest 7040A to the largest 7382A.

I very much hope/wish Genelec applies the W731 technology to smaller models and/or the next gen ONES series.

 

[richard12511]

I very much hope/wish Genelec applies the W731 technology to smaller models and/or the next gen ONES series.

The Ones + W371 is such a cool concept. Probably the best "stereo bass" solution that I can think of.

 

[Ilkka Rissanen]

Hi @Ilkka Rissanen, it is great that you're here on ASR! Would you be able to speak to the rationale/benefit for using paper as the cone material on the 8351B woofers?

The cone material in the 8351B and 8361A racetrack woofers is glass fiber reinforced paper. The material combined with the geometrical stiffness of the conical diaphragm gives the best balance between mass and stiffness. Due to three way design, the woofer bandwidth is quite limited which gives more freedom with choosing the material and its properties.
We are not fixated to any material when designing diaphragms/cones. Each driver design is considered as an individual and the best possible material is chosen for it. With regard to the 8351B woofer, the best performance was achieved by using glass fiber reinforced paper.

 

[stevenswall]

Also interesting that it measures so well with a seemingly simple cabinet design. They must really know what they are doing.

Wouldn't "nail six flat sides together" be simple cabinet design?

This requires custom moulds, pouring heated aluminum, and actual engineering to make a zero parallel sides, zero diffraction edges enclosure. I'd say this is the most advanced enclosure, though it does seem simpler once you have the two aluminum sides to seal and bolt things together.

 

[stevenswall]

That MDC coax really looks the part - huge midrange voicecoil, probably more magnet strength from that neo ring than most 8" woofers have.

Glad they use neo and spend weight elsewhere... Seems like most these days use archaic ferrous stuff because heavy=good and they don't realize they can make better performing drivers and use the weight for a more rigid cabinet, bracing, etc.

 

[dfuller]

Glad they use neo and spend weight elsewhere... Seems like most these days use archaic ferrous stuff because heavy=good and they don't realize they can make better performing drivers and use the weight for a more rigid cabinet, bracing, etc.

Well, in fairness to ferrite, it doesn't particularly care if it gets hot, which makes it a generally better choice for woofers.

 

[LTig]

If you are familiar with my background/history, you know that subwoofers and low frequencies are very close to my heart! I have worked as a project and design lead for many of our subwoofers, ranging from the smallest 7040A to the largest 7382A.

Did you design my 7060B? Nice sub, it compliments my K&H O300d (sorry) very well.

PS: just saw your pic in the 40th anniversary book I got on Highend 2019 in Munich in the Genelec booth.

 

[mkawa]

@Ilkka Rissanen is the 7060 permanently discontinued with only the SAM version available from here on?

 

[Sebastiaan de Vries]

The cone material in the 8351B and 8361A racetrack woofers is glass fiber reinforced paper. The material combined with the geometrical stiffness of the conical diaphragm gives the best balance between mass and stiffness. Due to three way design, the woofer bandwidth is quite limited which gives more freedom with choosing the material and its properties.
We are not fixated to any material when designing diaphragms/cones. Each driver design is considered as an individual and the best possible material is chosen for it. With regard to the 8351B woofer, the best performance was achieved by using glass fiber reinforced paper.

Thank you for sharing IIkka. My jaw still drops every day when I listen to my 8351B's from the clarity, pinpoint focus, and layers of sound the 8351B's are capable of.

Although I am using them at home, When I listen to all kinds of records, it is as if I am sitting in the control room. It isn't speakers I am listening to, but transparent windows holographically re-producing the recording scene.