Tubeulent: anyone have/try one of these tube preamps?

[Bassguy1]

From what I can see the big difference this has from other tube preamps is that it has a power tube and a preamp tube. The design makes a lot sense IMO.

http://thetonegod.com/tubeulent_photos.html

[aborgman]

Originally Posted by Bassguy1

From what I can see the big difference this has from other tube preamps is that it has a power tube and a preamp tube. The design makes a lot sense IMO.

http://thetonegod.com/tubeulent_photos.html

Yeah - this is basically a small single ended tube amp, driving a dummy speaker load. Although to get the weight as low as they did, they must be using some sort of switching supply.

I'm in the process of building something very similar out of an old Akai M8 tube reel to reel amplifier.

[bongomania]

This one is news to me, but FWIW there have been a half-dozen other devices with the same idea-- a tube pre with a small tube power section into a dummy load-- and they have done poorly in the market. H&K, Lexicon, Warwick, Stephenson, SAMAMP, and SWR are the brands I know of that have tried this.

[Rick Auricchio]

I still have a Hughes & Kettner "BATT," alluded to by bongomania.

http://www.cfcl.com/rick/personal/batt.html

[will33]

I wonder how they're doing the sag control. In the world of vavle jr. modding, there's a cheap easy mod that adds a resistor to create sag, vary the resistor value to give more or less sag. It's not actual voltage sag but mimicks it.

[aborgman]

Originally Posted by will33

I wonder how they're doing the sag control. In the world of vavle jr. modding, there's a cheap easy mod that adds a resistor to create sag, vary the resistor value to give more or less sag. It's not actual voltage sag but mimicks it.

Well, it's not voltage sag caused by a drop across the rectifier (whatever it may be) - but it's still a voltage sag dependent on current draw, so as far as anything downstream can tell it's basically the same.