2. amps-preamps
  3. 194162-10279

Weird crackling from speakers when preamp connected

I've got an MC275 hooked up to a VTL 2.5 preamp, when I reconnected it after some maintenance, whenever I turn the preamp on then the amp, once they both warm up, the crackling starts.

I hooked up the amp to my DAC and had no issues with crackling, swapped tubes, interconnects and power cord, different inputs/outputs, same crackling issue when using preamp but no issue when connected to the DAC as a preamp.

Sonus Faber Olymica !, MC275 Amp, VTL 2.5 preamp, Auralic Vega DAC, nordost interconnects/speaker cables, panamax power conditioner.

My last step is to see if I can either borrow a tube preamp or buy a cheap one to test it.

Any suggestions are welcome as I'm running out of ideas.

 

maddog66blue
ghdprentice
8,289 posts
 

Do you have a spare set of tubes for the preamp? Swap those in. 

I assume it is both channels. If only one then swapping tubes between channels would help verify. 

 

maddog66blue OP
34 posts
 

I've swapped tubes & confirmed they're good.

 

soix
10,503 posts
 

Sorry, that sucks.  What maintenance did you have done?  The times I’ve heard something like that was from dirty connections between components and interconnects, so if you haven’t I’d try cleaning those connections especially on the VTL with Deoxit or something similar if you haven’t already.  Pray you don’t need repairs from VTL because their reputation for service, especially if you bought used, is awful.  Best of luck in finding a solution. 

maddog66blue OP
34 posts
 

I had it looked at by a professional, they ran tests & checked the tubes, no issues when they had it hooked up and couldn't reproduce the issue. I haven't tried to clean the terminals, but may give that a shot.

 

More to discover