Saturday, August 6, 2011

The McChanson 300B marzEtT - O, woe is me, as Ophelia said

The legendary Vanch Carroll once told me that "tube amps can be an adventure or a horror story sometimes too." How right he was. There I was playing this beautiful 300B valve amp with the wonderful GuiGuang 300BS-Z valves in them and enjoying every minute of it. Detailed music, atmospheric, sound stage incredible, high end sparkling, mid range clear as a bell and bass solid and prominent. No fat flabby bass here, thank you.

Now for my budget system it doesn't get any better than this, but I did something stupid. I realised that I was supposed to be writing a review of how good the new McChanson was, and all I was doing was wallowing in the pleasure of one set of valves. Yes, the GuiGuang 300BS-Z had captured me and I had gone off into musical La-La land, which is actually a nice place to be. But then a devil pops up on my shoulder and reminds me that I am supposed to be listening to several other pairs of 300Bs as well. That was where I did something stupid. I listened to the devil.

So out come the GuiGuangs and in go a pair of Winged Cs. I love Winged Cs from St Petersburg in Russia, mostly they make such great valves. But this time one of them was bad. The 300B in the left channel flared inside soon as I powered up, and this was followed by a flare from the socket. Fortunately, that was it and after all the fireworks the valve just sat there smoking, even after I turned the power off.

The end result was that I blew the left channel. Even with a good valve there was no sound. Got back to Eric Chan, the maker, and he gave me a series of diagnostic tests to run on the circuit. There could have been much damage to the amp, but it turns out that one of the main resistors acted like a fuse and burnt out when it was overloaded. So all I need to do is get a new resistor and solder it in.

Eric really is amazing. He makes beautiful amplifiers and the support he provides is incredible. He's also a very nice person with bucket loads of knowledge.

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