• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Ok guys, get your daggers out.......

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I am probally read as a 'know it all' at times per my posts. I been designing my own projects for a while. I have had access to 100s of vintage tubes.

The other day I placed 50 HY 400 ohm DCR plate chokes in my monoblock driver/splitter tube circuit & my SE stereo linestage. I have been a stickler regarding top quality components, but never used a plate choke.

The amps simply opened up more than I heard before. I will not ever build small signal amp without a plate choke.

Now for interstage driver transformers I bet I also have something to learn........
 
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amperex said:
I am probally read as a 'know it all' at times per my posts. I been designing my own projects for a while. I have had access to 100s of vintage tubes.

The other day I placed 50 HY 400 ohm DCR plate chokes in my monoblock driver/splitter tube circuit & my SE stereo linestage. I have been a stickler regarding top quality components, but never used a plate choke.

The amps simply opened up more than I heard before. I will not ever build small signal amp without a plate choke.

Now for interstage driver transformers I bet I also have something to learn........


now you start to learn what "signal energy" really means....
:clown:
 
For some years I've used and old ECL82 p-p o/p tranny as a p-p plate driver one in one of my p-p amps and yes the sound "opened up" despite distortion figures showing worse than for R-C loading. The beauty is the massive voltage swing available.
Clearly there's more to this thd business that needs explaining i.e the relationship of the output stage and driver stage Miller effect and varactor properties.. However, the Radiotron designers bible explains the plate choke well.

richj
 
I experienced the same thing with my 12B4A preamp. I'm using the primary of a line transformer...along with a dollup of plate-to-grid feedback. Jack at Electraprint has very reasonably priced plate chokes that will be used for my next project, although they can get pricey if you want to use them with a power tube.
 
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