Lazy Spire ?

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ivonovi

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Hello there from sunny Australia.

I needed some help with a Spire speaker that is misbehaving. Just to give you some background, the speakers are about 2 years old and were bought from an authorised seller in sydney.

About three months back one of the speakers started misbehaving. It would basically switch off on it's own when I was listening to something at a low volume (around -40 on a yamaha receiver). The other speaker would continue to remain charged and would work fine. To turn the speaker back on I would have to turn up my amp really high (-15) and then it would charge back on.
I raised this with the Martin Logan re-seller and he promptly got a replacement power board sorted> That seem to have fixed the problem, but it is now back.

So to summarise, one of the speakers automatically switches off when i am listening to something at low volume (not very low), the other continues to work fine. To switch it back on I have to turn the amp really high and then the speaker switches bck on. I have tried swapping the channels on the amp and it is the speaker (irrespective of which channel it is connected to that switches off). Any thoughts on what could be going on would be greatly appreciated and valued.

Another way I could describe it is that it's a lazy speaker...switches off when the volume is not very loud and then needs high volume to get going again :(
 
You are fortunate that you bought from a dealer in your part of the world.

They should be on top of this assuming they have integrity.

I would not preclude your yammy AVR from the list of culprits.

GG
 
You are fortunate that you bought from a dealer in your part of the world.

They should be on top of this assuming they have integrity.

I would not preclude your yammy AVR from the list of culprits.

GG


Thnks GG.. there was no way I was going to spend that kind of money and not have the warranty etc. . So went the legit way and with a dealer :)

Regarding the Yammy.. I have swapped the speakers around and it is the same speaker that switches off.. ...so I reckon that should rule out the AVR..

Any thoughts on what could be causing this behaviour ?
 
It's unlikely to be the fault of the receiver.

The speakers inside have a circuit that detects if there is any signal, and if so, it will switch on the HV panel and I guess woofer amplifier too. Somehow either this part went bust or there is a bad connection to it.

Your spire should have a little LED status light on the back, so check that. (read the manual to see what it does)
 
Hi Ivon,

Based on your description, seems like it could be a "cold solder" issue.

More signal, more energy, issue goes away. Just a guess.

Good luck.

GG
 
Thnks Tosh/GG. Yep I will give the dealer a shout..it's just that will mean a couple of months turn around time to get it fixed and I was hoping to narrow down a fix which i could do. But all good....I will report back once I get some resolution.
 
Hi from the Gold Coast. I agree - let the dealer (Audioconnection?) get them right. I'd certainly be looking for the cause of this though - two boards don't just fail without a reason unless you are very unlucky. Something within the speaker is causing this I'd say.
 
is there a way to bypass the signal sensing circuit?

My Summits will sometimes do this at low volume levels. When my system shuts off, the power to the speakers gets disconnected, so I'd really like to just bypass this "feature"
 
Tom, the signal-sensing circuit most likely is used as a trigger to a relay. If you can get the schematics, it would be a simple matter to lock the relay in the ON position. I expect that Roberto is familiar with this.
 
I could be wrong about its' purpose, but is directly in the music sense circuit, and that model seems to clamp at very low voltage, rather than opening at high voltage. The mains circuit feeds the transformer directly. The two don't seem to be related. The only other things in the music sense circuit are 1) small Zener Diode, 2) 2 resistors 3) bridge rectifier. I've complicated this significantly.

If it were my speaker, and I didn't feel comfortable testing and replacing some of the components, I would remove the power supply board from the offending Spire, and take it to a small electronic repair shop for testing and repair of the music sense circuit.
 

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