The foam is to absorb (dampen) the back phase of the tweeter. And the coil is not burnt, it just has broken wire because of too big excursion. You could unwind one loop and solder it to its contact again.

I only use tweeters while watching Dave's videos... that's all that is required!

Thought it was a couch foot on the thumbnail!

You should have pushed the dome in with your finger to get that endorphin rush. Then do the teardown.

pretty much that is how all tweeters looks like and this coil should be connected to the dome in poland, regeneration of our domestic tonsil brand speakers of this kind is quite popular because coils are avalable as replacement parts for a fraction of the price of new ones. besides they were made in custom colors for some speaker systems. i fixed some in the past and replacing those coils is not that hard, because most of them is self centering design.

The foam dome is used to dampen the sound of the diaphragm. Usually proper tweeters use silk.

The voice coil is likely to be double layered. Watch out for breaks around terminations, they can sometimes be repaired!

Great teardown!

The foam absorbs the rear wave of the tweeter. The tweeter emits the same amount of sound from the rear of the diaphragm as from the front, and something has to be done with that acoustic energy before it reflects back to the dome and is re-radiated through the thin dome material, out of phase with the drive signal. Also, yes - tweeter voice coils are very small. I have seen some smaller ones - just 16mm.

Since it is a tiny little sealed cabinet in there tuned to the frequencies necessary for the frequencies produced, the foam is also used to tune it to the right frequencies. A solid, compressible fill would increase the theoretical volume inside the cabinet.

That is typical construction for a cheap dome tweeter, the speaker may be open circuit where the break may be where the tinsel lead is soldered to the voice coil.

How do I attach my wires back on to terminals from the coil. They are now too short. Can I unwind some of the winding from coil? Solder heat? I assume very low? What guage is this coil wire and who sells it?

the foam on the magnet is a damper for the sound at top end

Right at 1:38, you can see were the epoxy is rubbed off the winding and it's darker (heat) is most probably the point of failure.

The thing lies guts out : ladies and gentlemen, I don't where it's blown. Is it ?

back in the 70's i took apart "woofers" (note quotes) that had magnets about that big! lol

“I believe the coil was glued to the dome”...come on, you surely KNOW this!

Chineseium

Dave trying to understand the black art of acoustics! Excellent :)

come on dave, where is your adventurer spirit? lets have some fun repairing this tweeter

The hole is standard, its to equalise the cone pressure to ambient air pressure as its moving. The foam is to prevent the dome crashing against the magnet at high excursions.

KRK Rocrap :)))replace the tweeter with couch feet! Will sounds the same....

Please help me. I have a problem Speaker KRK ROKIT 6 GEN 2. Bass / Subwoofer sound is very audible from the sound the original. Sometimes a tweeter dies and lives again, dies again, so over and over again. I think what parts should I fix?

hi dave you its not top shelf so how much different would a top shelf tweeter be?

The foam is there to dampen any resonant frequencies between the diaphragm and the flat metal surface of the magnet assembly. As the distances between the diaphragm and the flat metal surface are within the wavelength of the sound being reproduced, removing the damping will introduce harmonic distortion due to resonances. When restoring tweeters this fact should always be taken into consideration. Failure to do so will lead to replacements sounding metallic and really rather rubbish, compared to the original. Human hearing is designed to comprehend and assimilate the most minute phase differences between ones ears, that is how we hear in 3 dimensions. We are born with 2 ears, both of which are phase correlated to each individual. We all naturally hear the world in binaural vision and can hear direction through 360 degrees in the x and y plane (quite amazing if you think about it). This is achieved by our brain being able to ascertain phase correlation differences between both input sound pressure waves. Sorry. Geek Rant End :-))

The foam is not doing nothing, it is for dampening accustic resonances but still allowing movement of the air inside the whole tweeter assembly into the permanent magnet housing. You're compressing and depressing air with any dome movement, so the air inside has to move and deal with that. :) BTW: almost any speaker modules are "moving coil in permanent magnet" type as you would need special amplifier devices that can deal with the high voltages that electrostatic devices would need to provide the electrostatic forces needed for an electrostatic speaker. I would agree that there actually may have been some ferrofluid there because you see some brownish gunk on the coil carrier material (the aluminium foil-ish tube). Maybe that's the cause why the coil did not get really dark and did not have black burning marks, because it still did get some kind of cooling as long as there was flluid left. The whole thingy must have seen massive signals that heated up the whole coil carrier which then probably did weaken and rip off the whole coil assy from the dome. That's why the coil assy was still in the slot when you dismounted the soft dome.

Is that coil printed on a flat flex?

There is indeed a lot of design that goes in to making these things work well. The magnetic field linearity, the suspension linearity, resonance in the cavity, dome profile and doping agent. The list goes on.

Hey Dave, Tried to log into the EEV Blog forum today. Got the following message " Please try again. If you come back to this error screen, report the error to an administrator." I Tried again and I came back to that same error screen. This is the only way I know of on how to 'report the error to an administrator'

oh god. there it is... thousands of these buggers i've replaced... literally THOUSANDS... one of the connecting wires to the coil becoming disconnected before the blue dab of glue was common....

Have you seen oil in the power transformers, if so do you know what it is

I have tweeters and the coating on the soft dome has flaked away. Can I use some sort of paint to recoat the dome.

So happy i never got one right now :3

How long before Dave starts selling speakers out of the back of an unmarked white van?

Better pro audio tweeters can be reconed, you can order the entire thing (all moving parts) as a kit. I done that many times when i was in the pro audio rental biz.

1:39 you can see the blowout as white shmoo with a bit of darkness in the middle. that'd be where it'd blown out 1:44 you can see the black spot next to the light reflection off the coil

hi do you have voice coil for pt6a pioneer tweeter

Hey EEvblog. On the Tweeter diaphragm right where the solder is for wire to pigtail is cut right there you could not see it with your Naked Eyes you have to put that under a microscope I do a lot of repair for these things back in the day now I prefer change them.

Do you know what exact textile the tweeter material is? I have one that’s deteriorating. The other is not. Maybe 2 different suppliers.

Wow, after that thrashing the coil actually survived well, the driver failed mechanically.

If you do a multimeter test between the actual tweeter terminals and the coil wire you'll probably get non conductivity on your DMM.

I didn't know you tweeted!

Speakers usually consist or a coil, spider, magnet , cone (if its bigger) and dustcap. The film or foil or metal the coil is wrapped around is shot, coil didnt look to bad itself, if its unusually dark the coil is blown, fck rewinding a coil btw

Dave, Any interest in doing a video on LoRa Wireless Communications? Im working on a project at work designing around a LoRa network and i find it to be beneficial for the frequency range to be utilized in industrial applications

in most pro audio PA systems the voice coil isnt too dissimilar. The replacement part for my EV DH1 horn/tweeter which is worth a few hundred dollars is basically the same just a titanium i think domeand a few more windings. My thoughts with most products is the difference in cost between cheap crap and expensive stuff is bugger all the rest of the money is marketing. The product that cost $2 and sells for $5 vs the product that costs $4 and sells for $200

those are silk soft dome tweeters and can be replaced very easy, they on sale on EBAY for a small price

Foam helps to damp out the resonant frequency of the dome itself , all vibrating objects have their own resonant frequency !

Nice video, needed more couch feet!!!

Mailbox soon?

has not blown its detached from the dome & is not repairable as it needs to be 100% central between the magnet & outer casing

Tweeters generally blow at the connection of the lead to coil wire. The black glue shit iow.

There is a rear chamber on this tweeter. The hole in the pole piece is there to vent the air generated from the rear of the dome into the rear chamber. This lowers the fundamental resonance frequency. The foam is there to help absorb reflections off the surface of the pole piece. Design of this tweeter is standard, but the rear chamber is something of an enhancement. Build quality looks shoddy from here.

You can buy recones on Ali for a couple of dollars, they look similar.

Don't know what "fancy" Dave expected to see, this is how a dome tweeter works, even $2500 Dynaudio dome tweeters are identical in construction.

In the background I heard a Canon camcorder timing out and shutting itself off. :-)

Maybe you can teardown an AMT or folded ribbon tweeter

Too bad you can't find replacements anywhere now, rumor is going chapter 11 and all replacements are out of stock.

Given the flame on the logo, I think they are supposed to be the 'Rocket 6'. Or am I being trolled

Get Medevil on it Dave! 😁

Wicked

Totally standard way to construct a dome tweeter.

I fried my old speakers on purpose, it had ferrofluid tweeters and man, that smelled bad :D

A generally naff speaker intended for audiophools..the modular amplifiers are a long, long way from any sort of quality and the drivers are cheap.

You should do a teardown of that PS4 controller you got.

I will bet if you glue the diaphram back on to the coil and stop destroying the coil... I bet it would work

What did Dave mean with "it's a moving coil type"? Aren't all speakers "moving coil"? (Except for piezos). I know "Moving magnet" only from turntable pickups.

Nice KRK plastic quality drivers...

Hey can you do a teardown of my mother in law? She's constantly overexerting and sounds horrifically distorted Maybe she's blown

I think you are right. The voice coil isn't blown. It just came unglued from the speaker cone.

Thats a quality for ya lol :D

foam is covering a vent hole

I am not surprised. The KRKs sound awful even compared to cheaper monitors. They only have a slight advantage at the low end. Probably why they are used for hip-hop and the like. But imho the advantage is not enough to justify the crappy mid-highs. Now I am curious to see what Yamaha and JBL are using

I took apart my headset, somehow broke one of the two speakers in it while doing other repairs, only to discover that I could get nearly identical replacement speakers for $1.80. The headset costs $270 new. (I bought it used.) I haven´t noticed any change in audio quality with the new spealers. They are of similar construction as the ones in the video.

40 volt square wave

Diamond tweeter domes FTW! check out www.bowers-wilkins.com/Discover/Discover/Technologies/Diamond_Tweeters.html ..leaves that crappy "textile" dome for dead!

Here's a tear down video kzfaq.info/get/bejne/edZzpc6Alt6RgaM.html

1:40 "It's been *blowen* " - Funny Australians 😆 Blown. Not 'blowen'.

I'm less than impressed with the KRK Rokit 6 powered studio monitor at around $300au each, I'm sure it does the job but the parts are cheap, amplifier module is very ordinary, you don't get much for you're money. I prefer to make my own speakers.

Is 'cactus' a new Australian term for f'ed up? ;)

High end audio...where the cheapest looking piece of junk can sound better than something that looks made in a Swiss lab. Half dark magic, half ridiculous engineering.

No ferrofluid? edits:lol right before the video said it.

Not many turn's and a flimsy coil former. The old Kef and Seas tweeter's were a lot better built, no wonder it died so easily.

The dome is caled a diaphragm btw

2:19 he must sit in a room and think of Australian things to say during his videos

Most audio equipment is wank. I'm surprised you were surprised at the design. You could probably find a basic calculator equation for voice coil design with a few Google's.

I used to call these "screamers" when I was young.

Michael Faraday 😃

HIGH

Whenever you say "cactus," I think you're getting ready to eat the thing. You don't even have cactus in Australia, do you?

Black gunck of deth..... Jezzz... 😂😂😂

Thats a tiny tweeter for a pro speaker.

You should get glasses or contacts.

Hi Dave. I’m almost sure that the reason why the tweeter failed is because the dividing network failed and the tweeter thereby was overloaded with low frequencies which the tweeter was’nt designed to reproduce. Your comments are very welcomed and appriciated 😉 Thx your vids🙏🏻 Best Regards

Yes. Eyesight fades out with time.

Could they not have used a ceramic or Piezo transducer for the tweeter.

People often overestimate the requirements on tweeters and subwoofers in terms of perfect reproduction. The human ear is nowhere that accurate in those ranges, so you can get away with much less effort than the mid-range speakers.

Lol blowen

Dave face realty you need glasses mate

T E X T I L E D O M E

I'm early! :)