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Passivising John Bowers Active Ones?

Story

I have a pair. One has been blown up for a long time. I have tried to repair them with an electronics professional but, to the amazement of the professional, we never could figure them out. This was six years ago.

I just dug them out of my storage and listened with the working one for about two hours and the bass amp blew up. At that precise moment I was just reading this thread (http://www.hifiwigwam.com/showthread.php?14737-John-Bowers-Active-One-sp...) where PAG jokingly gives someone's new Active Ones "one month of life... tops." Mine didn't even have that...

So, I think I'm now done with eighties electronics. The speaker elements are good and fine though.

Plan

Could I plug the passive side of the speakers directly to another amp? Could I use the original passive crossover (does its work between the LF and the LF/MF drivers) in the front compartment with the new setup? I would then of course have to use another crossover before that to divide the LF/MF signal to the original crossover and HF directly to the tweeter. Maybe a three-way crossover would be better?

The main problem I'm seeing is that the tweeter seems to be 8ohm and the drivers together 4ohm. In the original spec sheet it reads that the HF amp's output is 100 watts into 8 ohms and the LF/MF amp's output is 200 watts into 4 ohms. I actually just noticed that rolleye has suggested this before (https://www.vinylengine.com/turntable_forum/viewtopic.php?t=30450), but I don't know if they put the plan into practise yet.

Please comment and tell me if the idea is ridiculous or maybe even doable.

Cheers,
rubenandthejets



Passivising John Bowers Active Ones?

To answer myself, it is possible. I needed the help of a pro to figure this out though.

So, I took the frugal way and utilised the original passive crossover, which is actually just a low-pass filter for the bass driver. The MF/LF driver originally played the unmodified signal straight from the 200W MF/LF amp. In my setup it plays through a 50 uF capacitor, i.e. a high-pass filter. The tweeter signal goes through a 3 uF capacitor. This is only a prototype. I am very happy with the sound. Using an old transistor Marantz SR800, the sound colour is surprisingly close to what it was using the original Bowers amps. Really cool.

The problem is now that when the working active unit blew up last time, it blew up both LF and MF/LF drivers. Such a shame. Now I'm at the same situation as before: only one working speaker. Only this time it is passive, not active.

Now I have to repair or replace the snapped wire over the voice coil. Anyone know of a place that could maybe stock replacement elements or replacement cones? Also, does anyone know the name of these elements? Mine don't have the circular stickers at the back. They only have a printed date on them and the bass elements have a small sticker with a "B" on it. I know that they are 8 ohm nominal and about 8 inches is size.

My speakers serial numbers are 379 and 380.

Cheers,
rubenandthejets

Passivising John Bowers Active Ones?

I managed to find the Code No. for the woofers from an old service manual that I had. (Downloaded from here by the way, thanks isasurm!) It is ZZ8052. It is rather odd that the MF/LF and LF drivers don't have different codes even though they have different spiders.

Cheers,
rubenandthejets