quests electronic or panels failure?

[paaa]

Hi all, my new pair of old quests (z) arrived yesterday and they seem to be faulty.

hooked up to a krell kav 300i (which brilliantly drives my aerius), they sound excellent but in a minute the sound from the panels begins to fade until, 5 min later, the panels practically disapear. Only the woofer is working.

if I switch power off and reconnect the speakers a minute later, or so, this behaviour repeats.

I think that if the panels were dead they shouldn't ever produce any quality sound.

Is this correct? Am I experiencing circuit problems? Can anyone advise?

Many thanks
Paulo

 

[C.A.P]

Fading sound ............ One woofer down..... Id get in to the back of the x-over panel and look at the internal fuses. Sounds as if something on the board is on its way out. Panels don't fade out, they just play less db than the other one. Is it both speakers that fade out, or just one? If so switch the X-over boards and see if it fallows to that side if it does its the board.

 

[paaa]

I'm affraid that both speakers behave the same way.

After a power cycle they sound great for a while. Then the panels start to fade out until only the woofers produce sound.

I forgot to mention a detail, the speakers are rated 110v and I'm using a couple of external 220v transformers. As to the frequency I suppose that they are capable of operation either on 50Hz or 60Hz.

Do you think these circuits must be changed?

Cheers
Paulo

 

[Craig]

Yes the circuits would need to be changed. 60Hz US spec speakers are not capable of operating on 50Hz. I doubt your transformer is adjusting for the frequency.

 

[JonFo]

I'm affraid that both speakers behave the same way.

After a power cycle they sound great for a while. Then the panels start to fade out until only the woofers produce sound.

I forgot to mention a detail, the speakers are rated 110v and I'm using a couple of external 220v transformers. As to the frequency I suppose that they are capable of operation either on 50Hz or 60Hz.

Do you think these circuits must be changed?

Cheers
Paulo

Yep, that's the problem, you need to either supply a steady 60hz 120v line or get the electronics updated for 220v.@50hz

the easiet to do is to just get a PS Power Plant 300 on the used market. That will do the trick.

Or get some form of sine-wave generating line-interactive UPS that takes 220 in and generates 120v @60hz.

 

[Peter_Klim]

The reason why the previous owner of the ReQuests I own sold them was because he was moving from the States to Germany and would have to spend $300+ to get a 220V 50Hz internal power transformer from ML. So if need be, you could order it from ML (but I'm guessing it would cost more overseas). Good luck.

 

[paaa]

Great feedback guys, thanks a lot.
I'll keep you updated
Paulo