Amplifier goosed?

[RPDSoundandlight]

Hi all am hoping someone can help. I have a pair of Alto TS115A active speakers and one of them is not working. I have checked the main 15 inch driver and it seems to be ok, I have put a 9 volt battery across the terminals and the cone moves and there are no horrible grating noises when I push down on the edges of the cone. I have not checked with a multimeter because I do not know how to. When I play music through the speaker there is no sound but I can hear the tweeter although it is very quiet. Does this sound like a blown amplifier? The speaker was working at the last gig but when I tried it then it had this problem. Do amplifiers tend to die when left alone or can anyone tell me how to check with a multimeter. I have access to a multimeter its just I do not know how to use one. Thank you in advance.

Bob

[sandall]

First question - does the green Power LED come on? There is a fuse just under the mains connector. If you have a multimeter you can check fuses by switching to a low Ohms (resistance) scale. If the fuse is good a digital meter will show zero(ish), a mechanical one will go to full deflection.

 

If you can really hear the tweeter you probably do have power. Amplifiers don't die when left off, but they can die on switch-on, especially if condensation has got inside.

 

E2A: Maybe use a 1.5V battery, rather than a 9V one, next time. A multimeter across the terminals should show around 8 Ohms, but disconnect at least one of the wires from the amplifier first.

 

 

Edited November 6, 2019 by sandall

[jamesperrett]

Quiet sounds from the tweeter only sounds a bit like crosstalk which would mean that the amplifier is working but the signal isn't getting through. Check all the switches and connections first. Is there any signal from the Mix Out connector?

[RPDSoundandlight]

First question - does the green Power LED come on? There is a fuse just under the mains connector. If you have a multimeter you can check fuses by switching to a low Ohms (resistance) scale. If the fuse is good a digital meter will show zero(ish), a mechanical one will go to full deflection.

 

If you can really hear the tweeter you probably do have power. Amplifiers don't die when left off, but they can die on switch-on, especially if condensation has got inside.

 

E2A: Maybe use a 1.5V battery, rather than a 9V one, next time. A multimeter across the terminals should show around 8 Ohms, but disconnect at least one of the wires from the amplifier first.

 

 

 

Thank you for your help . am going to check it again. Might be something daft like a crap connection somewhere. Watch this space!

 

Quiet sounds from the tweeter only sounds a bit like crosstalk which would mean that the amplifier is working but the signal isn't getting through. Check all the switches and connections first. Is there any signal from the Mix Out connector?

 

Thank you for your help . Am going to check it again. Might be something daft like a crap connection somewhere. Watch this space!

 

Ok have tried it again using different cables and bypassing the mixer. (straight from my phones 3.5mm jack. I can hear the tweeter but its intermittent to be honest. By turning up the volume a bit on the speaker then turning it back down to where it was seems to make the sound come back through the tweeter. still no sound at all coming from the 15" Driver. So am guessing its an amplifier fault. I dont know how to test the output of the amplifier with the multimeter if I am honest. Take it to someone who knows what they are doing is the next step then?

[sandall]

Take it to someone who knows what they are doing is the next step then?

Yup :) Any Alto dealers in your part of the world?

[RPDSoundandlight]

 

Take it to someone who knows what they are doing is the next step then?

Yup :) Any Alto dealers in your part of the world?

Yes no problem, I will get it in for checking out. I have been using my trusty passive speakers and my kxr1500 amplifier whilst my active speakers have been off poorly. I forgot how heavy they are! Surely it must keep me fitter all that lugging about!

Bob