Der prates meget her inne om modifikasjon av Vifa XT25
. En diskant som jeg liker meget godt i utgangspunktet, men tenkte jeg skulle modifisere i et prosjekt sammen med noen Peerless HDS 164. Det står mye her på dette forum, men har ikke funnet noen god guide med bilder og slikt. Jeg fant en som bor i nærheten av meg gjennom et annet forum og fikk noen tips om hvordan fra han...., så da gikk jeg i gang med modifiseringen og har tatt litt bilder for å kunne bidra litt og vise hvordan det gjøres.
Jeg skriver resten på engelsk i tilfelle det er noen andre der ute som kan ha nytte av dette.
Here's the guide on how to mod the excellent Vifa XT25
tweeter and hopefully make it even better.
Tweeter before mod;
First unscrew the front plate.
You'll end up with something like this:
Use a small but somewhat stiff brush to apply water around the phaseplug:
The glue will expand and become white like this:
Now carefully try and insert a small and flat screwdriver in under the phasepluc and try to twist and ... turn.... and make the phaseplug come off. When it's not attached to the membrane anymore, just pull it out using... some pure force. ... And then lift the whole part with the voicecoil and the membrane off the magnet part. It will then look like this;
Remove the glue. If you let the glue have some time to dry a bit before you try to remove it, it will go easier (a minute or so). After you have removed the glue; you'll have these parts;
Membrane with the glue removed;
The magnet gap and where the phaseplug was glued to:
Then ... The modding starts. The thing you have to do is to remove some excessive glue around the outer edge of the membrane (on the inside). You also have to close the gap in the voicecoil with some glue (seen in the upper right corner).
The inside WITH glue looks like this (the reflective part is the glue that you have to remove):
Another picture before modification:
Use a small brush here as well (the same brush if you're smart) and apply water. Then use some small tools to rip the glue of. ... The glue will become white here as well;
The tweeter with the glue removed;
assemble the tweeter (use some glue to attach the phaseplug to the membrane):
... and you're done!
The sound should now be improved... More "open" and with somewhat more sensitivity.
So how does it sound? ... Well... I have just mounted them and had only a couple of minutes with them now, and I'm amazed by the sound they produce. I'm not able to tell you "how much better", but at least there was a difference in sensitivity as I had to modify the tweeters crossover. It was also at night, so ... maybe the cleaner powergrid has to take some of the blame, but I could have spent hours ... maybe weeks listening to them. ... then something called me to bed. This tweak should also improve distortion at higher levels, but I'll try that later today. Anyway; No cons so far... only pros :)
Hope it works though! :)
Thanx to people in the hifi-community for "exploring" this speaker and providing some info on how to do this. Especially thanks to the guys at the hifi4all.dk forum and Steen Duelund
which has played his part in the "exploration" of this excellent tweeter.
I hope some of you might find this guide helpful... and feel free to contact me!