My Express Clones

[McGinnis]

Hi Guys here are my two expressessss
I added a choke, and a half power switch. These things Kill. Built one with spragues one with generic polyester caps, the spragues are much crisper & clearer. Anywho thought you guys might like.
Cheers
Chris
[IMG:639:479]http://i163.photobucket.com/albums/t281 ... G_0874.jpg[/img]
[IMG:639:479]http://i163.photobucket.com/albums/t281 ... abs042.jpg[/img]
[IMG:639:479]http://i163.photobucket.com/albums/t281 ... s013-1.jpg[/img]
[IMG:639:479]http://i163.photobucket.com/albums/t281 ... abs017.jpg[/img]
[IMG:639:479]http://i163.photobucket.com/albums/t281 ... abs019.jpg[/img]

[RJ Guitars]

Chris,

Looks like you had some real fun and made a killer cabinet. Obviously you followed your own drummer in the layout, how closely did you hold to the original schematic? I am always curious about the various iterations sound compared to the original. From your comments I have assumed you believe you are getting an authentic Express sound. Have you sorted out for yourself what you think is important in achieving the Express sound and which changes you made in the layout that weren't significant in changing the character of the amp?

I'd love to hear some clips when you get a chance,

thanks,

rj

[M Fowler]

Chris,

Nice work on those amps and that cabinet is killer.

Mark

[RJ Guitars]

Hi Guys here are my two expressessss
I added a choke, and a half power switch. ...

How do you get half power on an Express?

[M Fowler]

This is how Ceriatone does it rj.

Mark

[McGinnis]

Thanks Guys. I've never played a real Wreck so i can't compare. The Wood one has polyester caps and no choke. It sounds smoother but maybe a little to saturated for me. And doesnt seem to have the punch of the Sprague loaded one.
I used Webers Java schematic as a baseline. https://taweber.powweb.com/store/java_schem.jpg
Both triodes of V1 before vol & tone stack. On the wood one I put a dual/single triode switch on V1 but it didn't make much difference. The half power is pentode /triode switch on the power valves like a Silver Jubilee, same as the Ceriatone setup, This works really well. I think I like the tone better in half power mode, a little less punchy,warmer.
The lay out is my own. On my chassis V1 & 2 are up front by the inputs & controls, I put a 5 turret strip right between the tube sockets .I went point to point where I could. This worked out well I think for noise control I think. I also put a 12AT7 in the phase inverter which cleared things up a bit.Oh, I also used 2 mallorys for my first coupling caps.
[IMG:639:479]http://i163.photobucket.com/albums/t281 ... s007-1.jpg[/img]
Cheers
Chris

[paulster]

This is how Ceriatone does it rj.

Mark

Ah, the infamous pentode/(quasi-)triode switch.

It's a waste of a hole in the chassis and a switch!

[M Fowler]

Yeah I've never had the desire to try that switching.

[selloutrr]

If you want half power just pull two tubes.

[RJ Guitars]

If you want half power just pull two tubes.

I'm not sure what you meant... I'll guess you were thinking Rocket or Liverpool output section. In an Express that's not an option - or did I miss something

However, there is a lot of chatter these days about the SE Express that just takes the signal off of one side of the tradition phase inverter and ignores the signal from the other side. In theory (sorta) you could pull one output tube from an Express and have your single ended amp. I'll venture to say that you probably have an awful sounding amplifier otherwise unless you do a few more things, but you'd be close to half power.

rj

[McGinnis]

I really like the half power switch guys. You loose some bottom and punch but that can be compensated for in the tone controls.

[Reeltarded]

Pent/Tri switches always work to some tonal advantage. Over 5 watts, half-power switches aren't about output. It's a joke.

Triode is soft and sweet, and pent is pointy, and brite. Half power is the difference between ear_blood vs eye_and ear_blood.

Pulling two tubes is a very good idea!

[paulster]

Triode is soft and sweet, and pent is pointy, and brite.

A true triode would be soft and sweet. I've always found that quasi-triode mode on push-pull amps makes the sound much thinner and more nasally.

Not a good option in my book, unless you can make it work tonally.

The volume reduction isn't worth the effort either, unless you really need those 3dB!

[vibratoking]

To me, quasi triode has a little less high end and almost no difference in volume. It is not half-power. What I am talking about is not the same as turning of two tubes. In an Express, you can't pull or turn off two tubes because there are only two tubes in the output section to start with. Am I missing something? Well, you can turn off two tubes, but then the amp is completely silent. It seems many posts in this thread are talking about mods to quad output sections?

[RJ Guitars]

...Am I missing something? Well, you can turn off two tubes, but then the amp is completely silent. It seems many posts in this thread are talking about mods to quad output sections?

Thank you!