A Couple Komet 60 Inquiries...

[PCollen]

1) Why is the 220K into the PI needed...what is the effect of this component other than reducing signal level into the PI ? Can it be eliminated with no ill effects ?

2) The 220K/330K divider into the third pre-amp stage fixes any signal into that stage at a 40% reduction. Going with ONLY the Express 150K would seem to really 'unleash the beast' but make the Komet less versatile. It seems that replacing the 330K with a 270K, and the 220K with a 250KL pot might be a nice mod at this point, allowing 50 - 100% of the second stage signal to drive the third. In fact, that's what I would call it: a Drive Control. Any thoughts/comments on this ?

As I've NEVER even seen this amp, I can only speculate. However, I'm considering replacing the board in my JTM 50 kit with a Komet 60 boardas a 'summer project' and am getting my thoughts together.

[Jackie Treehorn]

The express second stage is biased colder so it doesn't have as strong a positive voltage swing. Consequently, it doesn't need the extra attenuation. Amps like the Komet or Allesandro Bloodhound that have the second stage biased more symmetrically need some attenuation so they don't overload the third stage.

I think the Komet also has higher plate voltages which would also generate more voltage swing.

[funkmeblue]

anyone do a side by side comparison of the bloodhound and the Komet?

[PCollen]

anyone do a side by side comparison of the bloodhound and the Komet?

You might get a more timely response if you were to initiate a NEW THREAD with this topic. Why not delete this, and re-post as an original inquiry with a topic perhaps like : Komet vs. Bloodhound Comparison.

[funkmeblue]

info about the 220k resistor can be found here..... http://www.aikenamps.com/ click on tech info, then advanced, then grid resistors-why are they used? then scroll down to reasons for the resistors. Grid stopper=high frequency low-pass filter......blocking distortion.....helps take the "edge" off.

[PCollen]

info about the 220k resistor can be found here..... http://www.aikenamps.com/ click on tech info, then advanced, then grid resistors-why are they used? then scroll down to reasons for the resistors. Grid stopper=high frequency low-pass filter......blocking distortion.....helps take the "edge" off.

I'd like to know if anyone has eliminated it, or shorted it out, and evaluated the results. Funny that the Express doesn't use it, perhaps due to that difference in positive signal swing mentioned in an earlier response. I think one would have to scope it out, and ultimately hear the results, to fully evalute if it could be eliminated. I'll find out, eventually, but I always build it stock first before making ANY changes. I'm also using DC voltages like the Express, vs. the the significanly higher Komet voltages. I can't get those higher voltages in the 'donor' amp I'm using.