Firstly the tweeter, I understand this is suspended like NBLs/DBLs. The plate is slightly different however these, the plate is screwed down tight, no grommets with 1 inch screws.
On the back of the plate is weather strip. To my mind this surely negates any suspension that was happening, is this a ‘mod’ of some kind?
I guess the IBL mk1 was the first incarnation ever of that tweeter plate. My two pairs IBL mk1 had just that config. Strips and screws (nothing more than the small screws) tweeter plate mounted flush to cabinet (the sections with the screws) Mk2 upgrade included grommets so I guess it was the evolution, but suspension is working anyhow (maybe a bit different), strips may prevent rattle.
On my next IBL exercise, I’ll transfer them. When I replaced the old tweeters, the difference was large. I can see why the previous owner wanted to sell them. When the tweeters were replaced, they turned from ‘grey’ into ‘alive’ if that makes sense.
I have seen documentation on the mk2 upgrade and it was more like a shrinking tube that was to be put half way thru the screw hole and compress when fastening, to act like grommets. I wonder if all mk2 was like this or if there where actual grommets later on in production of the mk2?
I never tried grommets because I’m obsessed with original. I’ll only try if I could source original grommets and screws (if screws also changed to fit grommets).
Great news you could actually get the brass bits off from the tweeters with such little damage. I wonder if super glue is the original compound? Seems reasonable I agree.
About ten years ago I ordered a set of eight grommets, via my dealer, for my IBL tweeters.
My recall has it that they looked the same as those that do the same job on my current Allaes, and the same as those that fit between the Allaes’ PXO and cabinet. Someone here will know for sure.
Sadly I don’t think they are off the shelf or at least I cannot find them. I tried 3D printing them in TPU for my DBLs, but its not fine enough at this scale. So I am using grommets from a multipack from amazon, not ideal.
The reality is for this age of speakers the grommets go really hard, so I don’t think they are doing their job anymore and need to be swapped out in all cases. I have done three pairs of NBLs and a pair of DBLs in all cases the grommets were rock hard.
Of course there is suspension only tuned differently? I don’t understand you don’t understand? Anyway the grommets are regarded as a upgrade, and still original IBL (although mk2) so go for it.
One thing I always wondered about the IBLs is what torque the bass drivers should be set at? Was there even a precise torque for them back in the days?
I tried high numbers when I rebuilt my two pairs into one perfect one. I tried 2,5-3,6mm and found 3,5nm to sound the best. With more experience of torquing speaker drivers today, that is a very high number.
Well, I want to know everything about these speakers tbh Thank you for starting the thread.
I think you got the ones for the pxo, not the tweeter plate?? But I also want to know more, originally mk2 it was what looked like a piece of shrinking tube that compressed on each side of the plate when fastening. Yes, and that added metal washer GeoffC mentioned.
Anyway the grommets are regarded as a upgrade, and still original IBL (although mk2) so go for it.
Thank you for starting the thread.