Sonab OA-5 Type II

[Ceristimo]

Those Sonabs really have a lot of secrets hidden in their cabinets. Opening the cabinet was a lot easier then I first expected. After unscrewing all ten(!) screws, I could just take it off. But then, after searching the inside, no capacitor or anything that looks like it. On the backside of the baffle is a tightly screwed small thingy with two spools. My guess is that that thing is replacing the capacitor? Cause I've searched the whole inside, but I couldn't find a capacitor.
There is this thick red/black wire going all the way down into the cabinet. I followed that wire but there was nothing. It was attached to the connector on the outside.
Oh, before I forget, there was something written on the back of that thing (Yes, I took it off to take a closer look. I was curious).

It reads:
Sonab 3-1087

All the speakerconnections on it are numbered, from H1 to H5.

Some pictures:

Backside of the baffle.

Opened cabinet.

That thing with the two spools I meant.

P.S. Before you ask, there was a plastic basket covering the backside of the woofer, but that fell of the moment I lifted the baffle. I think it's supposed to be screwed to those three screws I wasn't allowed to touch, but that plastic thing is all messed up and just fell off!?

[Martin Dellstig]

Ouch!

The blue thing beside the two spools (inductors) is the capacitor.

Ít looks to me as if someone has already been inside this speaker.

I don't recognise the material covering the cables to the tweeters.
Nor do I recognise the capacitor, on all my old OA-5 there has been a capacitor in a metallic housing that looks older than this.
Anyhow, the value of the capacitor is probably printed on the capacitor.

Regarding the basket, are the three holes for the screws damaged ?

Best regards

Martin

[Ceristimo]

I guess you're right. One of the screws holding the baffle was so tightly screwed in that it was sunken into the baffle about half a centimeter. The wood around the screw also was damaged because of that pressure. I didn't pay attention to it yesterday, but now that you meantion it, it looks like it has been opened before.

Now, about the capacitor. I've looked everywere on that blue thing, but there is nothing printed on it. There's only something printed on the back of the inductors, "Sonab 3-1087". I already thought that the blue thing would be the capacitor, but since there's nothing printed on it I began to doubt.

And yes, regarding the plastic basker, you were right again. One of the holes for the screws is severly damaged. The other two aren't, so I should be able to put it back (I did already) but now it's tight to two screws. I don't know if that's a good solution, but as far as I can hear, the bassproduction is exactly the same. The sound hasn't changed.

What should I do know? Get me those capacitors we were talking about earlier and just solder them in? I haven't opened the other speaker yet, so I don't know how thát one looks from the inside.

[Ceristimo]

Oh boy, can't believe it's been almost 20 years. I'm still alive... . As are the Sonab OA-5 type 2's by the way...


So, those Sonab OA-5's belonged to my dad who bought them new in 1972. I have vivid childhood memories of the late '80's, early 90's of those speakers in the living room loudly playing classical music. I got those Sonab's in the early 2000's as a hand-me-down when my father bought new speakers, but I never got them to play right at the time. The treble was always coming through somewhat distorted. It's what prompted me to start this thread, but I (obviously) had no idea what I was doing and couldn't get them to sound correctly, so I gave up and stopped using them a few months after first posting here. I didn't know what to do with them and didn't have the space then to keep them sitting unused, so I brought them back to my parents' house and put them up in their attic.

And then life happened; I got married, had kids, moved away, bought a house and my dad's since passed away. Throughout all those years, those Sonab's just sat there. In the dark. Collecting dust. Somewhat forgotten about.

However, I was cleaning up the attic of our childhood home a few weeks ago when I stumbled across the Sonab's I put up there somewhere late 2005'ish. They've sat there for nearly 18 years in a dark corner. But underneath a thick layer of dust were my dad's old speakers.

I couldn't leave them sitting there. So I took them home with me and cleaned them up. They cleaned up quite nicely actually, so I ordered some female DIN-plugs, and once they arrived I hooked the old Sonab's up to my current Marantz amplifier.

And whaddaya know: Whatever treble-distortion was there 20 years is gone. All speakers play (the woofer and all 4 tweeters), the sound feels lively and a tad on the bright side but they do sound good, and there is not a hint of distortion. Not a hint.
Is it my older ears being less sensitive? Is it that the problem 20 years ago was whatever amplifier I was using then (I think it was a late 80's Sony TA-F100?...). Did the Sonab's magically fix themselves by sitting stored away for 18 years?

I have no clue. All I know is that they sound good.

And so I'm happy to report my dad's old Sonab's have found a permanent place in my living room. They are now in use as the rear channel for my surround setup, and let me tell you; Carlsson's ortho-acoustical approcach really works amazingly well as a rear channel setup.

Before the Sonab's I ran bookshelf-speakers on stands on either side of the sofa as my rears, and while it sounded fine, you could definitely tell the rear sound was coming from two 'hot-spots' on either side of the sofa.
But now when watching a movie, the entire wall behind the sofa comes to live. It's hard to properly explain, but you can hear the sound next to and behind you without being able to tell exactly where the speaker is placed. These speakers make a ton of sense as a rear-channel!

I'm thrilled I kept them and stored them, and I'm happy my dad's old speakers are playing once again. Plus, they have a high WAF-factor for being so unnoticeable. The veneer on the Sonab's coincidentally has nearly the same color as my flooring and they just kinda...blend in.

This story ended well


EDIT;
Huh, re-reading my last comment apparently at least one of these has a damaged damping basket for the woofer, since it apparently 'fell off' when I attempted to take one of them apart back then. Both speakers sounds exactly the same to me however, and the bass (while not overwhelming) is quite all right. Perhaps the Marantz Audessey room-correction I ran on them got them both balanced out; I have no idea, but their sound matches and it sounds more than fine to my ears.