Experience with AMR DP-777


Hi there, I'm fairly new to audiogon, but have been assembling high-end systems for about 15 years now. Recently bought an AMR DP-777 and swapped tubes and it killed my left channel the first time. I'm no stranger to swapping tubes (in DAC's and Preamps), so I was surprised this happened. I've read some other threads that this sort of stuff has been an issue with this DAC. Of course the DAC sounds, but I have two questions/points:

1) for those of you that have experience rolling tubes with this DAC, what is your procedure to make sure it does cause some any system failure with the unit?

2) second thing is I've sent the unit in for the SE upgrade and will be able to report back to you guys the difference/improvement in sound, as I know it's sonic signature very well
jsch123

Showing 5 responses by audiogalore

I have a DP-777SE and been experiencing no sound whenever it is ran for a period of time. In order to reset sound I need to power down and let it sit for an hour or so after power on is set sound is restored! Have anybody experience such an issue? 
This is reply I received from the AMR group in England:

"We have ran this past our Technical Department, please find their
comments:

"It could be the relay switching for muting. Either the relays or the control-IC get too hot.

Does the customer have enough airflow around the DP-777? If yes then the main board may need to be serviced (if in warranty) as the Relay control IC overheats (it includes over-temperature protection)."

Can you please confirm the airflow?"

Also when you say as follow:

There are some posts over on CA forum on this topic.  I googled it and could not find? 

I see where this can become a major issue and AMR need to careful not to let issue go on much longer or they definitely will lose market share!