July 2nd, 2000
Erwin Wiesbauer
Schwieberdingen, Germany (1166km round trip)

Erwin and I met over the net, how else, by talking about tubes. This was about 3.5 years ago I think. My previous job took me to Frankfurt etc on a regular basis, this is not too far away from where Erwin lives (near Stuttgart). I stopped by about five times so far, each visit ending up with hours long of tube discussions and ideas. We also traded a lot of tubes, this is where I got almost every european tube from :)

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"You again?!" (but then in german!)

I arrived in Schwieberdingen at around 2 pm thanks to the traffic jams along the way past Stuttgart. "Them tourists should be stopped at the border and sent back...!". We had enough time to catch up on our ideas and even do some measuring on Erwin's amps. He has gorgeous sounding 50 mono-blocks driven by KC3's. We measured about 1.7W at normal listening levels through an 8 ohm resistor (He didn't want to risk a feud with his neighbors). At around 5.9W the amp started to show deformation of the sine wave, so we took it that the amp could muster about 5.5W. The cause was the driver we noticed, it was starting to go past cut-off on the grid since it was biased at -3V and getting near 4Vrms input. Still impressive from a 50 tube: 5500mW!!!!

Erwin has some very good ideas and designs. His al(most) DHT riaa/preamp is the best example... if only I had a record player :) It only has an IHT in the input stage, after that it's all DHT's up to the speakers. He does have some extra gain though, about a factor 6. He's working on it I think, it should let him drop a whole tube stage.

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Al(most) DHT riaa/preamp

All good things come to an end. I had to start work the next morning at 8 am, so I had to leave early in order to catch some sleep. I got back at 00:30 am and had some nasty rain/thunder storms along the trip home. I saw about twelve accidents along the high-way. The rain was so heavy I couldn't even see the end of the hood of my car at some points. I survived though without a scratch! Took me about two hours extra to get home, but I made it. On to the next trip!!!!