I have a MK III and have found it fantastic in OTL mode with my Senn 580's. Transformer mode is probably best left to the low ohm phones. I did look under the hood and EVERYTHING says Mark II on the boards. My best guess is that the Mark III is a Mark II with the power supply in a separate box...

Quote: Originally Posted by Blasyrkh can anyone explain to me exaclty which is the difference between the DT and OTL mode? saint.panda, are there any tubes that can kill the siroupy sound on the mg head? DT puts transformers in the output, OTL is "output transformerless". As...

I purchased a Mark III exactly one year ago and have put about 300 hours on it without any hiccups. I also got a pair of 580's at the same time and find the sound to be very warm and enjoyable. The OTL position sounds better IMO also. This is by far the best experience I have ever had with...