Attempted Simplification of the Express - Non Traditional

[eazilyled]

Love this idea and really interested to see how it turns out.

[RevD]

Great idea guys, I wish you every success. I think its very much possible to get the tone with a more reproducible form and I think you guys will figure it out. Good luck!

Kindest regards,

Don

[RJ Guitars]

RevD - I hope we figure it out. This has never been an easy beast to conquer but I thought that if we do sort out a way to conquer it, it would be nice to have that exact same formula work next time?

In the meantime for all those guys that are nervous about posting their rough prototype efforts, I'll give you an example of my own here if that makes you feel any better. What I find is that when I get really finicky then I take forever to get a project done. Along with that it almost always ends up that I have to tear it apart and it ends up ugly when I put together a new idea. In the attached photo you can see how I butchered out that chassis with the "push-pull" saw... the machine shop cut the rest of them for me so they look professional.

I have wired up all the power circuits. I found the 5V tap very handy for powering the pilot light and everything else is pretty standard. It tests out OK and I even put tubes in it to see if they light up... onward.

rj

[Colossal]

What I find is that when I get really finicky then I take forever to get a project done. Along with that it almost always ends up that I have to tear it apart and it ends up ugly when I put together a new idea.

Hahah, that is so true! +1

[M Fowler]

rj I'm anxiously waiting for my package to arrive buddy.

Mark

[xtian]

rj I'm anxiously waiting for my package to arrive buddy.

Mark

+1. I'm building a pair of Rockets! Soldering starts Friday!

[dorrisant]

Here you go...

[IMG:766:432]http://i946.photobucket.com/albums/ad30 ... 819315.jpg[/img]

Upon further thought, those pi caps and tail resistor are wrong... I was looking at rj's old layout. Oh well, it will be alright eventually. Just didn't want to hold back on the pics.

Tony

[dorrisant]

Updated...

[IMG:766:432]http://i946.photobucket.com/albums/ad30 ... 546955.jpg[/img]

Now waiting on parts...

See any thing fishy... I need to swap out one of the 100ks for an 82k in the pi...

[RJ Guitars]

I finished her up today - I figure I had about 12 hours total in build time. For many of you it would probably be more like 8. I'm not especially fast at anything but especially prototype amp building. It was really fun and even though i was making up a lot of it as I went along, it went pretty smoothly - therefore quickly as well.

I think I created a better way to wire up the brite caps and keep the leads very short. FWIW - It will work on a traditional Express build as well.

I am using a new tube from Russia for the preamp tubes. They are VOSKHOD 12AX7's and super cheap from AES. For the power tubes I have a NOS set of SVETLANA EL34's from the 80's.

How does it sound? - Very Express like and quite good at that. I have not built a lot of these and only one that you could call a traditional format so I am no expert on the Express sound. I do think I would be very pleased with Geetarpicker at the controls... it seems like everything dials in nicely. Great clean to mean sound and as expected way louder than I can ever hope to use. It has more clean headroom than any previous Express I've built. This is the first one with all Edcor transformers so lots of new info being revealed here.

It looks great - I did slow down and tried to pay attention to the wiring and the soldering. I'll attach some photos and I like the results well enough I'll have to think hard before I alter that circuit board design. I grew to like it a bit more than I thought I would as I put it together although I'm still convinced it could be laid out better.

Enjoy.

rj

[xtian]

Nice! It's really elegant with the PCB. Almost PTP, but easier!

BTW, it took me about 16 hours to build Rocket Dog #1. I figure 12 hours for #2.

[guitarsnguns04]

Looks great rj...nice layout....did you consider mounting the sockets into the board as well? It would cut down on the build time even more I would think. But I guess there's always the durability issues that go along with that as well. Anyhow...nice job

[jeff12]

Nice looking build rj. I like the tube sockets mounted to the chassis, should hold up well to tube changes. Also like the heater wires under the circuit board, very clean looking. Finished one of my amps today also, thanks for the help.

[Bob S]

Looks excellent RJ.
Goodness right out of the box is impressive.
Keep up the great work guys.

[fishy]

Looks good RJ. Your passion and overall enthusiasm is quite something.

I think keeping the tubes chassis mounted is a good idea. Saves stress on the board for sure. We know V1 tends to be a tad touchy......

Any reason for not pursuing radials for the board or is that another chapter?

[dorrisant]

Nice rj, looks great! Thanks for the pic, it will be my guide.
Great to know that it sounds good... but how good? Any noise compared your other builds? I'm assuming no, since you didn't mention it.
Great work rj!