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previous: Tailpiece I've got these strange tubes, 8417 ... -- 8/26/1999 3:59 AM

Re: Weird Tubes

8/26/1999 11:14 AM
Graywater	Re: Weird Tubes Tailpiece, Wanna sell 'em? These are some of my favorite tubes for really high-powered, simple biasing amplifiers. the sound is something like a 6550 but much warmer - still quite clean though. These tubes have a much greater "power sensitivity" (between 2 - 2.5 times the 6550 transconductance) than 6550s and you can drive them to full output with just a few volts - 31v p-to-p for 100W, easily accomplished with a simple split-load phase inverter. Just think, a three tube (no tone controls) 100w amp, a 12DW7, and the 8417s. As best I can tell, these are very rugged, long-lived tubes something like the best of the NOS 6550s. I built myself a guitar amp with them using the Bogen iron about 10 years ago and I now use it as a small stand-alone PA amp 'cuz the damn thing's so loud - I really like Deluxe sized amps at present. So, enjoy them, but realize that replacements will be hard to find once those are gone - I generally don't design around a tube unless I've got three "sets" in stock - a more-or-less "life-time" supply for me. GW

8/26/1999 11:14 AM

Graywater

Re: Weird Tubes

Tailpiece,

Wanna sell 'em? These are some of my favorite tubes for really high-powered, simple biasing amplifiers. the sound is something like a 6550 but much warmer - still quite clean though. These tubes have a much greater "power sensitivity" (between 2 - 2.5 times the 6550 transconductance) than 6550s and you can drive them to full output with just a few volts - 31v p-to-p for 100W, easily accomplished with a simple split-load phase inverter. Just think, a three tube (no tone controls) 100w amp, a 12DW7, and the 8417s.

As best I can tell, these are very rugged, long-lived tubes something like the best of the NOS 6550s. I built myself a guitar amp with them using the Bogen iron about 10 years ago and I now use it as a small stand-alone PA amp 'cuz the damn thing's so loud - I really like Deluxe sized amps at present.

So, enjoy them, but realize that replacements will be hard to find once those are gone - I generally don't design around a tube unless I've got three "sets" in stock - a more-or-less "life-time" supply for me.

GW