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View Full Version : Rebuild needed of Aquarius 4 xovers..advice needed



ian r
04-14-2018, 01:04 AM
So deeper listening of my first and new to me Aquarius 4 reveals volume inbalance and tonal shifts between channels

I havent yet accessed the internals behind the potentiometer plate as i notice its sealed in

As i bought the units from a retired JBL dealer and service agent who had refoamed the Let8h's i think the xovers are the next port of call

Is there any members who have knowledge of breaking the seal of the xover plate and as a newcomer I wonder if kits to rebuild the xovers are for sale?
Im not very teccy at the component and circuit level so a ready pack or drop in might be best....any pointers most welcome.


I know from drohs post below the following

[QUOTE=droh;380188]As I restarted this project I first took on dealing with some of the internal components, here are pics of the crossovers before and after. You'll notice some strange stuff going on here. One of the crossovers had either been repaired or maybe reworked by the factory. It actually shows markings that it might have started out as an LX-12-5 crossover, but the crossover for the AQ4 is an LX12-7. You can also see that the wax cup was opened up, what you can't see is that the coil had been replaced. For some reason they then used that expanding insulation foam instead of wax for the repack.

I replaced all of the components in the crossovers, the capacitors for obvious reasons, but I also replaced the coils, the one that was in the repaired crossover was wildly out of spec (44mH instead of 2) I'm not sure why it was wrong, it had the correct markings, maybe it was damaged at some point, maybe my heat gun did it in when I removed it.

The second pic shows the new components in place, the last pic shows the crossovers after I refilled them with fresh bees wax. It all looks much tidier now.

I also replaced the L-Pads with new old stock exact replacements, plus a couple of new sets of genuine JBL push connectors.[QUOTE]

But

Is removing the back input and pot panel a glue free and non destructive process?

I also find the 1970's push connectors very restricting re modern cables, what JBL kosher inputs should i look for.... so im thinking of that modification too

Im certain I need to go in the cabs for the xovers not just to inpect but also as one of the presence pots is either kaput or needs cleaning.

apologies for crossposting

Odd
04-14-2018, 01:34 AM
You may get some help from my thread;
JBL S109 Aquarius 4 restoration (http://www.audioheritage.org/vbulletin/showthread.php?35758-JBL-S109-Aquarius-4-restaurasjon)

You can remove the crossover by screwing out six screws. It is not glued.
Push the filter into the box.
You must take the top off to get access to the filter.
Unscrew the black plate on which tweeter speaker is attached.
You will now see screws that hold the entire top in place.

Edit, Link was incorrect.