So, since the donor iron i have is a little high on the B+, I am going to build an asteroid instead. just have a question or 2.
- Has anyone built one with a SS rectifier instead of the tube? THe iron has no 5v tap.. ic ould add another transformer, but i would prefer not to.
-Has anyone built one into a combo? any issues with excessive vibration?
I am waiting on a few parts before i start up on it. and will do my best to keep a build record.
And finally... I am crappy at Tolex, but how the heck do you get that funky-a$$ "V" ???? That might be neat on the top of my combo. or maybe not... lol
I found a few things online, but no schematic. My guess would be that it's an Express with a higher voltage PT, 50W OT, cathode follower, and fast/gradual switch.
I think it would sound great with ss rectifier. pretty much anywhere from a deluxe reverb (with no reverb) to an express sounds good to me. Theres a lot you can do in there.
I've been trying to deduce the Concorde from different threads I've seen. From what I can tell if you start with this schematic and add a direct-coupled cathode follower to the very end (removing that .022uF cap and moving the 220k series resistor to the output of the cathode follower), then reduce the 10k cathode resistor to 3.3k and remove the 220k resistor in that 220k/330k voltage divider (leaving only the 330k to ground)...then that's what I think is close to the Concorde. But I don't know voltages and that's probably not exact but I think it's in the ballpark. I built something like this and it had gain out the wazoo so maybe I'm missing something that reduces gain (IIRC I ended up using a 4.7k instead of 3.3k and put the 220k series resistor just before the PI to ground instead of series, with a .1uF cap between cathode and 220k to ground...that sounded pretty good but I was using Express voltages...with the cathode-follower pulling them down a little).
dartanion wrote:Isn't the Concorde a SS rectified Komet.
Yes.
Fisherman: you are right on. However, the filtering scheme is different. The concorde has a typical marshall filtering scheme except for the preamp which is express-like. Voltages are in the late marshall 1987 ballpark.
It HAS gain out the wazzo. Hence the grad switch.
Only the concorde has a CF. And supposedly it's useless due to the very high impedance of the PI (unlike the impedance of the tone stack in a marshall preamp structure). I recommend experimenting with and without it and if the CF doesn't change the tone at all, I recommend using parallel input stages for lower noise (however it wields slightly more gain so some tweaks down the line might be necessary. Maybe swapping the 1M volume pot to 500K? Raeducing the 330K?)
Only the concorde has a CF. And supposedly it's useless due to the very high impedance of the PI (unlike the impedance of the tone stack in a marshall preamp structure).
In one of the threads I was talking about (on another forum) a well respected and knowledgeable amp builder questioned why that last 220k resistor was a series resistor...saying something to the effect that having it a series resistor defeated the purpose (or maybe 'negated the benefit' might be a better term) of the low impedance output of the CF. That's why I changed it to a 220k to ground (with a series .1uF cap between cathode and 220k to ground) instead of in series. My amp didn't have a Fast/Gradual switch although I did try it hardwired both ways.
IIRC a guy by the handle of 'sinas1' or something like that did a youtube demo of the Concorde and it sounded right on the edge of meltdown/instability.
Also, FWIW, I and others have tried shoehorning a cathode follower between the first stage and the tone stack of an Express/K60 circuit and it made virtually no difference. But it does change the tone when at the tail end...whether one likes it more or less is probably a matter of preference. It can sound good with or without it IMO.
Fischerman wrote:
IIRC a guy by the handle of 'sinas1' or something like that did a youtube demo of the Concorde and it sounded right on the edge of meltdown/instability.
That guy is Chris Cornell's guitarist. Youtube on Chris Cornell (latest band) and you'll hear more Komet sounds in a live setting...:-p
Yup. I was standing about 5 feet away from the stage at the Warfield for the Cornell show. The Concorde stood out above the multiple /13 heads. Both of his guitarist are great live.
Hey Allyn. Any chance you'd share your schematic? Pretty please.
