Yamaha msr400 problem

[blaineschultz]

I rented out my msr400 for a gig, the Dj said during the party someone "turned the volume to max on the amp" meanwhile his mixer volume was also maxed out. Needless to say the speaker is blown. I tested the tweeter and woofer. both are OK and checked out so the problem is in the amp.

Here is the problem:

When powered on with a signal being input no sound not even a hum is given off from the speaker, not even with the mixer signal maxed out. as i increase the master volume on the amp I get a vague deep hum. Once volume on the amp reaches 97-100% i get an exponentially louder deep hum, with no remnants of the track being played from the mixer.

Thoughts? this is a new one for me. The fuses look OK, I'm not sure where to start looking, obviously something in here was overloaded. Transformer? thanks in advance for your comments!

[doctor]

I rented out my msr400 for a gig, the Dj said during the party someone "turned the volume to max on the amp" meanwhile his mixer volume was also maxed out. Needless to say the speaker is blown. I tested the tweeter and woofer. both are OK and checked out so the problem is in the amp.

Here is the problem:

When powered on with a signal being input no sound not even a hum is given off from the speaker, not even with the mixer signal maxed out. as i increase the master volume on the amp I get a vague deep hum. Once volume on the amp reaches 97-100% i get an exponentially louder deep hum, with no remnants of the track being played from the mixer.

Thoughts? this is a new one for me. The fuses look OK, I'm not sure where to start looking, obviously something in here was overloaded. Transformer? thanks in advance for your comments!

I hope that the MSR400 service manual will be sufficient help.

[Jazz P Bass]

The first item that I would check is the output leads to the speaker.
Disconnect the speaker until you have the amp repaired.
With a DVM measure across the leads. There should not be any Vdc on the output.
If there is a large Vdc offset, the power transistors in the output section may be shorted.

[Janissary]

I rented out my msr400 for a gig, the Dj said during the party someone "turned the volume to max on the amp" meanwhile his mixer volume was also maxed out. Needless to say the speaker is blown. I tested the tweeter and woofer. both are OK and checked out so the problem is in the amp.

Here is the problem:

When powered on with a signal being input no sound not even a hum is given off from the speaker, not even with the mixer signal maxed out. as i increase the master volume on the amp I get a vague deep hum. Once volume on the amp reaches 97-100% i get an exponentially louder deep hum, with no remnants of the track being played from the mixer.

Thoughts? this is a new one for me. The fuses look OK, I'm not sure where to start looking, obviously something in here was overloaded. Transformer? thanks in advance for your comments!

Hello. I know it has been a while but i have a pair of MS400 and when the amp and mixer is maxed out i get just enough sound to play live music for a medium size venue. I also have MRS400 and its twice as powerful although it is 100W less compared to MS400. Hows that possible? Does mine has an issue or all of them are lije that? It doesnot peak im guessing that hreen light would turn red when it peaks but it doesnt. Is it safe to play like this ? Appreciate your answer. Thank you.

[g1]

It doesnot peak im guessing that hreen light would turn red when it peaks but it doesnt. Is it safe to play like this ? Appreciate your answer. Thank you.

Which input are you using? Where do you have the level control set? Is master control set to 10 ?
With master set to 10, turn up the mic or line level control until you see the peak light come on occasionally.