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lofi-ear
03-01-2009, 11:20 AM
As much as I feared it, It happened :(

I have absolutely no idea when, but one of the TW025 tweeters of my tik10's seems to have taken damage, luckily the other tweeter is ok.

As I play a sine tone between 3000-6000Hz, at lower volumes, the damaged tweeter sounds fine. But when I turn the volume knob beyond a certain point (still not very loud), instantly a very audible shrill distortion is added to the sound.

What's odd, I've never heard the amplifier to clip or played music at very loud levels. The speakers have always sounded a bit bright, so maybe the amplifier's tendency to lean to the brighter side has finally taken its toll.

I believe the original TW025 tweeters are no longer available anywhere, so what's the best replacement? How about a repair? Is it possible at home?

Earl K
03-02-2009, 08:55 AM
Hi lofi

- See what info you can obtain from Manfreds' saga on a repair to his 025Tis (http://www.audioheritage.org/vbulletin/showthread.php?t=20731&highlight=TW025) .
- It does seem there is an Audax replacement diaphragm available for your tweeter ( according to Reditech in France) .
- You might want to have a private chat with Manfred to find out the end result of his repair to a single tweeter in his pair of Ti2K .

<> cheers

lofi-ear
03-02-2009, 09:49 AM
Hi lofi

- See what info you can obtain from Manfreds' saga on a repair to his 025Tis (http://www.audioheritage.org/vbulletin/showthread.php?t=20731&highlight=TW025) .
- It does seem there is an Audax replacement diaphragm available for your tweeter ( according to Reditech in France) .
- You might want to have a private chat with Manfred to find out the end result of his repair to a single tweeter in his pair of Ti2K .

<> cheers

Thanks for your reply :) I saw that thread a few hours ago after posting my initial question and it did turn out to be very helpful. I'm glad there's still repair kits available, I can only hope they will take international orders.

Above 6000Hz the bad tweeter sounds completely fine, so maybe the tiny voice coil has bottomed and bent during heavy treble output.

As a warning to everyone, do NOT listen to Gridlock's music loud if you want to preserve your tweeters. (http://www.youtube.com/watch?v=qZ0uDbqg48g that's the song that must have inflicted the damage, before that everything sounded ok)

robertbartsch
03-02-2009, 01:51 PM
Are you sure it is the tweeter and not your electronics? I would confirm your diagnostics by swaping the speaker channels from left to right.

lofi-ear
03-03-2009, 02:30 AM
Are you sure it is the tweeter and not your electronics? I would confirm your diagnostics by swaping the speaker channels from left to right.

Done that, it's the tweeter

pos
03-03-2009, 02:49 AM
I can only hope they will take international orders
I they don't then I can help with the shipping :)

lofi-ear
03-04-2009, 11:19 AM
I they don't then I can help with the shipping :)

Very kind of you :) But I think I can get the diaphgram/voice coil replaced at the local harman service. If not...

What modifications should I make to the crossover network to attenuate tweeter response by 2db? Technical sheet: http://manuals.harman.com/JBL/HOM/Technical%20Sheet/Ti10k%20ts.pdf

Earl K
03-06-2009, 06:43 AM
Hi lofi,


What modifications should I make to the crossover network to attenuate tweeter response by 2db?

- I'd advise that you buy replacement diaphragms in pairs . This is because I believe it's still not resolved whether these ( Audax kits ) are exact replacments for the originals ( Ti25K ) . Make sure you buy the 4 ohm variety .

- Why 2 db more attenuation ? Is that just a guesstimate ?
- No matter, the minimal amount of ( original ) attenuation for the original tweeter is accomplished by a simple inline resistor ( R1 ) that is placed in the circuit before the 4-pole network / meaning all you need to do, is increase the value of that resistor ( say in .5 ohm increments ) until you get a tweeter balance that you prefer ( over the original "voicing" ) .

<> cheers

Hoerninger
03-07-2009, 05:39 AM
Look here (Europe):
http://www.audax-speaker.de/content.php?seite=shop/produkte.php&hauptrubrik=8&abisz=&archiv=&jahr=&details=5
http://www.audax-speaker.de/ibase/module/medienarchiv/dateien//PDF-Web/TW025A16.pdf
____________
Peter

lofi-ear
03-07-2009, 10:28 PM
I disassembled the tweeter and cleaned every part with alcohol and the distortion disappeared. :) I will however order the extra diaphragms just in case the trebles decide to blow in the future.

Earl K
03-08-2009, 05:45 AM
Problem fixed!
I disassembled the tweeter and cleaned every part with alcohol and the distortion disappeared. :) I will however order the extra diaphragms just in case the trebles decide to blow in the future.

- That's good news .
- If you do order replacement parts, make sure to get those with the correct impedance . ( According to the posted TiK tech sheet, the TWO25 tweeter that's in your TiK speaker is 4 ohms )

- By the Way, all Audax tweeters with a 1" ( 25mm ) dome start with a TWO25 prefix / it's the suffix that indicates the specific model type ( ie; TWO25A14 , as one example )

- To see what I mean, look through the Technical Information Archive of Audax Drivers (http://www.hautparleur.fr/) .

>< cheers