Hi all, I hate hearing that phrase. I have a NADY XA-300 amp that, just like all of the other ones, goes straight to protect mode after the fans spin up.
I have found a post on here or another forum that someone finally talked to NADY and it is a relay that has gone out but there is no other info.
I am not a tech but could easily swap a board and have replaced bad caps in an LCD monitor so I am willing to give it a try.
Any idea which relay or even where the protection circuit is?
I live in the sticks and the 2 repair places in town wont touch anything but TV's. Dallas is 2.5 hours away and shipping the amp would truly make it "not worth fixing"
Here are some pics from the net. Nothing is burned or swollen on mine.
I have hooked it up to a good known 8ohm load, removed fuse, and other troubleshooting steps.
Ideas on what to do?
I have found a post on here or another forum that someone finally talked to NADY and it is a relay that has gone out but there is no other info.
I am not a tech but could easily swap a board and have replaced bad caps in an LCD monitor so I am willing to give it a try.
Any idea which relay or even where the protection circuit is?
I live in the sticks and the 2 repair places in town wont touch anything but TV's. Dallas is 2.5 hours away and shipping the amp would truly make it "not worth fixing"
Here are some pics from the net. Nothing is burned or swollen on mine.
I have hooked it up to a good known 8ohm load, removed fuse, and other troubleshooting steps.
Ideas on what to do?
Attachments
It's a pro. amp, apparently for use in a public area with all the legal stuff, insurance etc. that goes with that.
It has a large switchmode power supply which, if it is faulty, may not be easily understood, tested or safely repairable by an inexperienced person.
Still want to try your luck? - You will need a schematic circuit diagram and so will others to assist. Better still, talk to a qualified audio repairer first.
BTW, what evidence is there that the problem is a relay? Does it fail to switch on, power up etc? There may be good reasons why a relay prevents power-up.
It has a large switchmode power supply which, if it is faulty, may not be easily understood, tested or safely repairable by an inexperienced person.
Still want to try your luck? - You will need a schematic circuit diagram and so will others to assist. Better still, talk to a qualified audio repairer first.
BTW, what evidence is there that the problem is a relay? Does it fail to switch on, power up etc? There may be good reasons why a relay prevents power-up.
It seems to be a widely known problem with this model. They all seem to do it randomly and NADY will tell you it is a flat charge to replace the relay but 70.00 for the repair plus shipping makes it silly since they are now available for less than 100.
The power comes on, light on and fans spin then the protection light comes on and it all shuts down.
The schematic is not out on the net. Just a block diagram. There are enough of them out there that I would buy another one for parts if I could narrow down which board it is on.
Protect mode most likely means the power supply is good. Most likely problem is a bad output transistor.
And that heatsink sucks, barely any fins :/ This amp cant be more than 10-20 watts rms per channel if even that.
If its rated more than 50 watts a channel i can clearly see why it failed.
If its rated more than 50 watts a channel i can clearly see why it failed.
With forced cooling a chimney style heatsink can easily outperform a much larger passive heatsink. Even a rectangular extrusion could work as a heatsink with a steady stream of air.
Inviato dal mio GT-I9001 con Tapatalk 2
Inviato dal mio GT-I9001 con Tapatalk 2
Nope - note those toroids on the boards near the output stage and also the 4 pairs of outputs for 300W, also the size of the SMPS. Maybe this is class D or G even? 😉
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120W RMS @ 8
Ω per side
150W RMS @ 4Ω per side
300W RMS @ 8Ω bridged
150W RMS @ 4Ω per side
300W RMS @ 8Ω bridged
Minimum 4Ω per side, 8Ω bridged
Cheap amp but worked fine for a pair of wedge floor monitors.
Yep, I didnt get an answer over there. Same amp as mine but his was totally dead.
But why would a class D amp have four emitter resistors per channel ? I'd say this is a class B amp, and there is no way that heatsink could support even a mono channel of 300 watts, not even with skyscraper ventilation system fan blasting air through it.
What?? There's a lot of transistors just on the power supply side, on plenty of heat-sink but also fan-cooled? Then a seperate fan with an aluminum tunnel on the other amplifier side? Assuming the power supply at least is switching-mode, it sure looks like a reasonably hefty power amp to me, just modern design and probably not class-a.
The XA-300 is (no surprise) a 300-watt amplifier, 2 X 150 @ 4 ohms. And it has 3 fans. Looks like a SMPS and probably more conventional class B output.
Those aluminum tunnel sinks with the fan blowing thru REALLY work GREAT. Looks exactly like 150 watts a channel X2 to me. Of course, the power supply inductors are small and the power transformer is admittedly tiny, but 150 a channel isn't much. My Crown CE-4000 didn't have any large or heavy components either.
I'd imagine the Nady XA-2100 case is a stuffed with more goodies...
Those aluminum tunnel sinks with the fan blowing thru REALLY work GREAT. Looks exactly like 150 watts a channel X2 to me. Of course, the power supply inductors are small and the power transformer is admittedly tiny, but 150 a channel isn't much. My Crown CE-4000 didn't have any large or heavy components either.
I'd imagine the Nady XA-2100 case is a stuffed with more goodies...
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What was said is that Dead out of the box was a bad relay. Your's doesn't sound like that. Then one fellow had a dead one that had a blown surgistor. They are cheap and commonly available. Post somewhere around here somewhere are the steps to basically trouble shoot most audio power amps.
What is amazing is that you can get a used real 2100 watt amplifer like the XA-2100 for $199 in good condition from Guitar Center. That's 10.5 cents a watt.
The XA-2100 looks like a conventional power supply Tekko might be more comfy with. Here's pics of the inside of the bigger brother:
Inside pics of a Nady XA-2100 amp - AVS Forum
When you can pick up one of these used for $199 it's a cheap way to build an amp if you can re-use those transistors and power supply!
There's also an XA-2400 model. I think they're all obsolete now though.
Inside pics of a Nady XA-2100 amp - AVS Forum
When you can pick up one of these used for $199 it's a cheap way to build an amp if you can re-use those transistors and power supply!
There's also an XA-2400 model. I think they're all obsolete now though.
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