Komet Pics

[snide]

Thanks for the kind words. Unfortunately the Komet shown here is not owned by me. A close friend of mine is a studio musician and he had the amp rented from a retail store for awhile. The amp sounded killer...very in your face aggressive. In the fast response mode, this thing has no forgiving for mistakes or slop in technique. I did notice the amp did not sustain quite enough on solo stuff. As I remember, the sound of this amp and the sound of my new express are similar. My express is a wilder kind of animal however.

Eric

[Omar]

Any ideas how the fast/gradual switch works?

Omar

[snide]

Omar,

Its the split load circuit on the second preamp stage. The plate resistance is split into two resistors (84K and 22K). The tap point between the two is sent to a switch on the back of the amp along with the tap point at the normal place (at the bottom of the series chain). The common terminal of the switch is then sent back to the coupling cap for the next stage. In the fast position the plate load resistance is 106K and in the gradual it is 84K. The circuit is the one with the funky coiled wire used for a shield (grounded on one end). I think Mark A. has a diagram in the "possible preamp mod file" in the files section. I'm gonna have to try this with my express and see how it works.

Eric

[HeeBGB]

Hey guys,

Is there enough info here to possibly get a schem or layout started?

I would definately like to build one of these. Anyone else seen the inside of this amp?

Thanks for these pics Eric!!

Greg

[BWilliamson]

In the fast position the plate load resistance is 106K and in the gradual it is 84K.

Actually, the plate load resistance is 106K in either fast or gradual mode. The difference is where the capacitor is tapping the signal from. The operational point of the tube does not change with the switch.

Fast mode, the signal is taken straight from the tube.

22K--82K--O----->second stage plate

In gradual mode the tap point is now the junction of the 2 plate resistors.

22K--O--82K---->second stage plate

So the signal coming off the plate going to the next stage has to fight it's way back thru the 82K resistor which acts as a voltage divider with the grid resistor of the next stage acting as R2 in the divider.

Now for the fun part, you can vary the value of the resistors to whatever you want as long as they add up to about 100K(if that's what your originally using and want to keep as a operating point) to fine tune the response your looking for.

bw

[snide]

Thanks for the correction!

Eric

[Ross]

Hey guys,

Is there enough info here to possibly get a schem or layout started?

I would definately like to build one of these. Anyone else seen the inside of this amp?

Thanks for these pics Eric!!

Greg

This is not an amp from a builder who can no longer build amps. Building a clone raises some ethical questions and may directly eat into Hogy's bottom line.

[snide]

Ross,

I tend to agree. I don't think it would be right to clone this amp verbatim. Looking at the pictures and gaining insight on the construction methods and the beauty of this amp is a different matter IMO. My hope is that there won't be any cloning that will damage Hogy's bottom line. If the consensus is that the pics should be taken down, then we should get Omar to do it . What does everyone think?


Eric

[HeeBGB]

Well I got into amp building because I can't spend that kind of money on a guitar amp without divorce papers. So if I was to build one Hogy didn't lose any money on me.

But I can see your point and maybe we should take them down.

All I know is I like the way it sounds and I REALLY want one!!

You know, I live in NJ and I have this idea that one day I'm gonna knock on Ken Fischers door. I hear he's a pretty nice guy. I don't have the balls for that though.

Hi Ken....you don't know me , BUT..........

Greg

[JimmyBlood]

First off, hi, just joined up here. Those Komet pics are great. I had yet to look inside one, but hear one regularly at a buddy's house. Those are works of art inside. I'd be extremely curious to know the details of those trannies. Apparently, it's a closely guarded secret, although rightfuly so! When exactly does the price get to the point where you'd have to build a clone rather than buy one? Right now these are still in the range of affordable in my opinion, and I'd love to support these guys, but it'd sure feel wierd to buy something new instead of brewing it at home. Do you guys build the Twrecks because of the price and scarcity of the originals? Would you buy one if you could? Just thinking about the ethics side of it all, solder fumes must be getting to me.

J.

[snide]

Hi Jim, and welcome to the group

If Ken was building trainwrecks and the cost was below 3 grand, I would would buy one from him in a heartbeat. Also I would build my own clone of it because It's what I love to do. I am thinking seriously about buying a komet....just gotta buy my wife something to pay her off first.

Eric

[rhinson]

hello there, very nice pics of one of the best twreck inspired amps out there. looks like this has a "cut" control like the vox style amps--i've often thought of putting one of these on my own amp--they are very useful on brighter amps. a question: do these run at the higher or lower plate voltage levels (ie-- around 400v neighborhood or around the 320v neighborhood) that most of the twreck inspired schematics show? also looks like these use a diode before one of the preamp supply dropping resistors. i've seen this in the torres book---something about keeping the power amp from stealing current from the preamp when you're playing cranked. probably a cool/cheap trick to try on any amp to see if it makes a difference in the response/feel of the amp. anyway thanks to you guys for the response on the 1k/25w resistors i had posted in the for sale section. they're almost gone! anyway, cool pics and cool group. rh
'

[toddyjoe]

That "diode in the B+ rail" trick sounds interesting. Anybody want to give it a whirl and report their results?

Also, I see no harm in posting the Komet pics on this forum. Given that all of us are here because we appreciate Trainwrecks and anything Mr. Ken Fischer has a hand in, we likely appreciate the Komet and look at those pics like looking at a piece of art. Sure, anytime you find amp pics on the Internet, someone is going to examine the pics and consider either cloning or incorporating some aspects of the design into their own homebrews. However, it is unlikely that homebrew amp builders and members of this forum would be able to put Komet out of business. The real risk to Komet would be enterprising amp builders who want to clone the Komet and mass-produce and sell the same as their own amp line, much like Callaham, Alessandro, Bruno, Two Rock, Mystic, Fuchs and other companies arguably tried to do with Wrecks, Dumbles, etc. However, any amp company that has the resources and ability to mass-produce and market a Komet clone also has enough resources to buy their own Komet and reverse-engineer it rather than peruse the 'net looking for Snide's pics.

I say let the pics stay unless Komet wants them to be taken down. If Komet asks to take them down, however, they should certainly come down.

[rhinson]

hello there, nevermind about the plate voltage question-----i read in another post (over at the gear page forum) that these run about 475v on the plates. quite a bit higher than the "normal" wreck schematics on file--hence the higher power rating and probably has a bit more clean headroom. anyway, thanks to any that may have looked for the info.
rh

[Omar]

I agree with toddyjoe on this one. I think there is high level of respect for Ken and Hogy among the members here. If Ken or Hogy preferred that the pics be removed I would certainly respect their wishes and remove them.

Personally, I looked at the pictures of more of an educational thing. I appreciate the high quality constuction and looked at the layout to make a schematic in my head so I had an idea of the topology. I was looking for ideas for my homebrews not to clone.

I also understand those that can't afford a Komet, would never buy a Komet, but would like to clone one. As long as this is for personal use (not for profit) I would think that this is acceptable. Anyways, without the correct transformers, it would be hard to copy so really calling it a clone may not technically be correct.

Omar