Posted by Tnuctipun [ 64.12.116.14 ] on March 05, 2005 at 06:39:33:
In Reply to: Building something new is not easy thing... posted by Tnuctipun on March 04, 2005 at 21:02:22:
anonomously quotated:
First impressions, clarity and chrispness in the highs and tight lowend likens to the step from dynamic transducers to planar. Center image is a little weak, but the total image is superior and the sound stage is much more in your face as well as significantly deeper. Finally, my speakers don't sound like they are sitting on the floor. The presence just sucks you into the music. To much steriophile BS, I like it!
Seems to be a near-universal reaction. His version runs 12B4's, and is shunt-regulated with VR gas diodes. Two 0C3, a 0C3 and a 0B3.
The Guinevere mod for this circuit is fairly easy. Two sockets for VR tubes( and these can be the mini "2" series instead of the "3" series Octals ), and another CCS to feed it. Probably have to run the HV from the 325 taps...
Another mod is to battery bias the CCS's. This improves the regulation by about an order of magnitude and improves the noise figure, related to the plate resistance of the valve and the size of R-3. The ratio of Rp/R-3 when made smaller improves the performance. With 4 Li-ion batteries and 12B4's, one can approach unity...
regards,
Douglas
[ GroupBuild Forum ] [ Help ]