Poping noise starting up Mcintosh MA 6900

Ibog,

What speakers are you using? The amp can not pass DC as outlined above because of the output transformer. I would turn the volume down and see if you still hear the pop. This may be system related and coming from a source component connected to the MA6900 or a ground loop. What are all of the components in the system including any AC conditioning?

Ron-C

Sorry,
I did not know that the 6900 could not pass dc.
Also, what kind of ground loop could cause a popping noise.
60cycle and harmonics of, but popping I have not experienced.

Thanks everybody for the responses, except for the pope one? I have tried turning the volume down to zero and turning it on, same thing. I have also turned it on with the selector button set to no component at all, same thing. I had called Mcintosh and spoke to Joe there and he said that it could make a noise on start up. But that it is not the way it should be. He said that the filter caps could be of uneven capacitance and as they even out, the pop could result from that. Although he never said that it needed repair, and that I should listen to others and see if they make the same noise. I also asked could it be another of my set-up, Joe said no. What?, I had hoped for a firm answer, either yes it is broken or no it is not. My retailer said he never really paid attention to the one on the floor. He said he would listen to one he has on display and call me back, he has not. To say the least $4600.00 later, I am less than happy! Is this the legendary Mcintosh service, is this typical of other retailers around the world?

I just heard from my retailer, he has offered to exchange my amp for another. I am still less than happy with Mcintosh tech support, felt they could have been more helpful. Hope all turns out well. Thanks for the posts.

The reason I suggested exchanging for a new one, was that I did know that McIntosh would back the dealer on the replacement. That is where they excell.
Glad you are now getting what you deserve, an amp which does not pop.
On the passing dc thing, I know that the gentleman could be correct, but I am always one to suspect the worst when it comes to something like this.
I have had McIntosh amps take out drivers before, so not passing dc must be new to their design. It has been several years since I attended McMasters. Maybe there were mitigating circumstances in my experiences. Anyway you are well served.
Good listening.
Larry