Genelec 8351B Teardown (2nd Disassembled)

[YSC]

This is a round plastic basin, and there is no problem I mentioned.

well, according to physics, especially considering the air loading on the creep surface, it isn't uniform load bearing either, if you look at any speaker driver in motion video you can see the surface vibrates a lot, especially at the breakup frequency, which if the creeps are problematic, it will be problematic in a circular cone also

 

[RobL]

Yours does not have the same problem as the disassembled one. How long has your 8361 been used? Is it used frequently?

Yours does not have the same problem as the disassembled one. How long has your 8361 been used? Is it used frequently?

It’s the oblique light in the disassembly pics that cause the so called “cracks”. Here’s the same woofer from my other post lit from above:

Suddenly a large “crack” appears on the crease…except there is no crack. If you could see the amount of glass fibre reinforcing these cones…I have zero concerns about longevity.

 

[zhaowo]

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Second time, I disassembled my 8351B again.

This time, I opened the speaker driver side and took a picture in more detail.

I wanted to disassemble the tweeter, but it was glued so I couldn't remove it.

The woofer looks like paper and the center is filled with solid foam.

The mid-tweeter driver is not directly screwed into the enclosure, but is pressed by the rear panel.

The notes on the amp module are curious.
This is 8351B, why is the amplifier module marked as 8341A? It seems to be a compatible part.

Then, I hope you enjoy it.

Is the long edge of the 8351b woofer caused by crease damage or fiber reflection? Can you take a clear photo?

 

[zhaowo]

It’s the oblique light in the disassembly pics that cause the so called “cracks”. Here’s the same woofer from my other post lit from above:View attachment 309192

Suddenly a large “crack” appears on the crease…except there is no crack. If you could see the amount of glass fibre reinforcing these cones…I have zero concerns about longevity.

This is actually easy to judge. Find a speaker that has been used for several years, remove it, and press the voice coil. If only the rubber edge moves, then there is no problem. If the long edge of the paper cone also moves, it is a problem with the speaker design. I don’t want it to happen. This problem occurs in the speakers of 8351, but through comparison of promotional video screenshots and disassembly pictures, it is obvious that the disassembly of 8351 is caused by material fatigue.

 

[zhaowo]

It’s the oblique light in the disassembly pics that cause the so called “cracks”. Here’s the same woofer from my other post lit from above:View attachment 309192

Suddenly a large “crack” appears on the crease…except there is no crack. If you could see the amount of glass fibre reinforcing these cones…I have zero concerns about longevity.

If there is no problem, that's great, I can use my 8361 with confidence

 

[tmtomh]

If there is no problem, that's great, I can use my 8361 with confidence

How do you get from repeated assertions of "basic physics shows that it's cracked," and "the material isn't rigid enough" to your most recent comment without acknowledging that you didn't actually know what you were talking about?

 

[zhaowo]

Repeating the same baseless assertion doesn't make it any less baseless. You have no evidence for your claim that it is cracked. And therefore every subsequent assertion you make ("cone design... is not rigid enough") is also without a shred of evidence. Not to mention, if the cone were cracked - which it is not - it wouldn't be because it lacked rigidity. It would be because it lacked flexibility.

Since we can safely ignore your assertions unless or until you provide some evidence, here's another couple of illustrative photos. This is an old terry cloth towel.

First, folding it around a tight radius so the pattern of the surface fibers is not parallel to the width of the fold:

View attachment 309183

This is a very soft and highly textured material so of course the surface looks different at the top of the photo than on the flat area at the bottom. But the surface is even with nothing that looks like a "crack" or irregular gap.

Now the same towel, same tight radius at the top, but with the pattern of the surface fibers nearly parallel to the width of the fold:

View attachment 309184

Huge visual gaps open up along the apex of the radius.

Unfortunately I don't have an item in the house easily at-hand that has a circular or elliptical grain/fiber pattern, but this clearly shows that the angle at which the fiber pattern intersects with the radius changes the appearance of the surface. And as noted before, there's no evidence that this surface appearance correlates with any structural problem with the material.

Can soft materials be used as vibration materials? This is the most basic common sense of physics
Do you think paper cones or fiber cones will have the phenomenon you used towels as an example?
Can you compare the new speakers from the production line with the disassembled speakers Are they the same?
Leave it to time, we can't prove each other's point of view

 

[zhaowo]

How do you get from repeated assertions of "basic physics shows that it's cracked," and "the material isn't rigid enough" to your most recent comment without acknowledging that you didn't actually know what you were talking about?

I say this to thank RobL who sent the photo, not to say there is no problem with the speaker. I hope it would be best if he has no problem, because I also use 8361

 

[YSC]

Can soft materials be used as vibration materials? This is the most basic common sense of physics
Do you think paper cones or fiber cones will have the phenomenon you used towels as an example?
Can you compare the new speakers from the production line with the disassembled speakers Are they the same?
Leave it to time, we can't prove each other's point of view

Genelec The Ones woofer creases/tearing mystery solved

I started a bit of a rant on this other thread and eventually got blocked by the mods, so I'm posting a new thread just to clear the air, because Genelec were kind enough to email me close-up pics of the race track woofers to prove they all look like that and it's perfectly normal. They also...

www.audiosciencereview.com

well, from the factory tour photo.... brand new, un used drivers from Genelec...

 

[zhaowo]

Genelec The Ones woofer creases/tearing mystery solved

I started a bit of a rant on this other thread and eventually got blocked by the mods, so I'm posting a new thread just to clear the air, because Genelec were kind enough to email me close-up pics of the race track woofers to prove they all look like that and it's perfectly normal. They also...

www.audiosciencereview.com

well, from the factory tour photo.... brand new, un used drivers from Genelec...

Okay, maybe I was misled by other production line photos. The bass of each model is different. If the official photos are like this, then there will be no problem. sorry

 

[Sancus]

Okay, maybe I was misled by other production line photos. The bass of each model is different. If the official photos are like this, then there will be no problem. sorry

So you made an account just to necro this thread and post misinformation without even reading the whole thing? Where it's clearly stated(repeatedly!) by a Genelc representative and shown in the above photos that the drivers are intentionally made that way?

Cool. Great. Thanks for your contribution.

 

[fineMen]

... that the drivers are intentionally made that way?

I can't get around the drivers' visual appearance. They look so much like cheap television speakers. Good that they are hidden.

But measurements show how much excellence is built in. Best in its class size wise, price wise. Compare the two aspects, the looks and what comes out. Would one actually suspect that they are made with sub-par craftsmanship, neglect even? The opposite. These thingies always wow'ed me, but now even more. Real engineering for real

 

[tmtomh]

I can't get around the drivers' visual appearance. They look so much like cheap television speakers. Good that they are hidden.

But measurements show how much excellence is built in. Best in its class size wise, price wise. Compare the two aspects, the looks and what comes out. Would one actually suspect that they are made with sub-par craftsmanship, neglect even? The opposite. These thingies always wow'ed me, but now even more. Real engineering for real

If they are best in class, perform well, are obviously thoughtfully and effectively designed and engineered, and are part of a line (not to mention company) that has an excellent reliability record and sells primarily into a demanding market (pro market), then the logical conclusion is that the drivers are not actually made with "sub-par craftsmanship," let alone "neglect." Why is this basic idea so hard to grasp - and why are you apparently so unable (or unwilling) to distinguish between (a) the build quality of the speaker and (b) an appearance that you personally "can't get around"?

 

[Sebastiaan de Vries]

I can't get around the drivers' visual appearance. They look so much like cheap television speakers. Good that they are hidden.

But measurements show how much excellence is built in. Best in its class size wise, price wise. Compare the two aspects, the looks and what comes out. Would one actually suspect that they are made with sub-par craftsmanship, neglect even? The opposite. These thingies always wow'ed me, but now even more. Real engineering for real

Actually they are beautiful! Have you seen the wonderfully tooled die-cast frames they are made off? I think they are one of the nicest designed racetrack drivers I’ve seen so far.

 

[fineMen]

... why are you apparently so unable (or unwilling) to distinguish between (a) the build quality of the speaker and (b) an appearance that you personally "can't get around"?

I'm infected it seems. Really, no irony, I have to learn, and I'm willing to, to accept the superiority of a team of highly qualified on a daily basis professionally working engineers

I come from the DIY camp. Now I'm converted. Finally I can't compete with e/g KEF. My previous 'framing' of how raw drivers should look like is completely stirred up. May be that's the case with the typical audiophile also. The Genelecs outperform every consumer product of similar size and cost downhanded. Showpieces of, finally, real engineering like Paris' Eiffel tower. Not actually 'nice' but an icon anyway. In case you can say that: Art sublime.

(So let me some room to breath in excitement.)

Review here: https://www.audiosciencereview.com/...ds/genelec-8351b-review-studio-monitor.23432/

 

[tmtomh]

I'm infected it seems. Really, no irony, I have to learn, and I'm willing to, to accept the superiority of a team of highly qualified on a daily basis professionally working engineers

I come from the DIY camp. Now I'm converted. Finally I can't compete with e/g KEF. My previous 'framing' of how raw drivers should look like is completely stirred up. May be that's the case with the typical audiophile also. The Genelecs outperform every consumer product of similar size and cost downhanded. Showpieces of, finally, real engineering like Paris' Eiffel tower. Not actually 'nice' but an icon anyway. In case you can say that: Art sublime.

(So let me some room to breath in excitement.)

Review here: https://www.audiosciencereview.com/...ds/genelec-8351b-review-studio-monitor.23432/

I first got seriously into hi-fi, courtesy of my father, around age 13. For about 37 years my understanding and aesthetic of amplifier quality, also inherited from my father, was "big iron": not tubes and not 5-figure audiophile-jewelry stuff, but still, massive Class AB amps, with more weight and thicker metal cases meaning more power and better fidelity. Similar deal for premium CD players with internal copper plating to reduce vibration and so on.

All of which is to say, I get it - we all have our aesthetic preferences and our sometimes-indirect standards for what counts as valid hi-fi equipment. And honestly, is there really anything wrong with holding to those standards when it comes to our own personal preferences? Heck no! I want my components to be black with minimal displays - virtually invisible so I'm not distracted by lights while listening to music. I don't want my hi-fi gear to look like art - I want it to look like as little as possible. But other people like silver faced components and backlit VU meters, or dramatic designs, or rack handles, or whatever. If it makes each person happy, it's all good IMHO.

It's only when we treat our preferences as inviolable, objective measures of quality that we can sometimes get into trouble - not just because such claims are usually unsupportable, but also for the reason you imply: it can sometimes prevent us from considering options that we might really end up liking!