Thursday, June 23, 2011

The McChanson 300B SET amplifier

About 3 weeks ago I took delivery of my second McChanson amplifier. It's beautiful, isn't it? Look at all those transformers - more iron less glass as Eric says. I have been so impressed over the last 18 months with the 6L6 amplifier Eric Chan built for me that I decided earlier this year that I would venture into the mysterious world of the legendary 300B.

It's early days yet, but it's impressive, very impressive indeed. Big sound stage, great bass and a detailed upper end. Lots of burn in to be done, with the amp, and also the 4 sets of 300Bs I have purchased over the last 6 months in anticipation of the amp finally arriving. I'll be eventually writing up my experiences after a lot more playing.

Check out the McChanson amplifiers on Ebay.

A Tale of Two Amps (continued)

Nice to see that I'm not the only one who has an appreciation for the McChanson SET and REDGUMs's Sonofa Gum. Johnny Darko's review of the Cerwin Vega CMX-6 loudspeakers sees them pitted side by side in the driving of these speakers.

What's really nice about this is that we are talking about two Australian amps that are both high quality, something different and great value for money. In this day and age that is something quite remarkable indeed!

Saturday, June 11, 2011

Getting Rid of the Grado Hum

Type "Grado hum" into Google and you will immediately find numerous discussions about the legendary Grado hum, which occurs with some turntables, most notably the Regas. Like many people I had thought that the hum issue was somewhat exaggerated as I had used a Grado Gold1 with a Rega and found the hum produced to be virtually inaudible. This was with the Grado Gold1 mounted on an RB250.

Recently, I purchased a Grado Sonata and mounted it on a Michelle Tecnoarm. Unlike the RB250 the Michelle Tecnoarm is not internally earthed and has an external earth wire that clips onto the earth terminal of the phono stage amp. Set-up like this the Grado Sonata hummed big time, so much so that I was feeling like taking the Sonata off and reselling it. Searching the internet did not reveal any sure fire solutions. Mu-metal shielding around the motor had worked for some people, but not for others.

Earthing the tonearm to the motor had also worked for some, but it didn't work for me. However, while attempting this, I noticed that the hum reduced in volume the closer I moved to my integrated valve amp. So I clipped the Tecnoarm's earth wire onto the metal front plate of the amp and the hum vanished instantly and completely. Even at full volume there is no hum audible.