Grounding the casing is OK.

Don't ground the third lug!!!

The 2 PPIMv are for:  1x setting max volume and 1x for setting a lower volume to play crunch chords.
The Clipper bypass excludes the last triode from the pre-amp.
That stage is setup like an asymetrical clipping stage.

Chassis with Trannies fitted in the cabinet no problems.
I ordered from a company in Germany TubeTown: http://www.tubetown.de

I even have two MV installed in my Express.
The first i s always on and sets the max volume that I can use.
The second I can switch on/off with a footpedal so I can have crunch chords at a lower volume.

I used a Type 2 PPIMV for the first and a Type 3 PPIMV for the second.
PPIMV = Post Phase Inverter Master Volume.

See the mods page on www.ceriatone.com, if you want to view all the PPIMV types,
then Google on: Trainwreck pages

MM are one of the best transformer making companies, but expensive.
The Toneslut trannies are made by Heyboer, good reputation, good tone.
If you want to go cheaper, then try to source Hammond transformers.

I have build two Express Clones, one with Hammond and one with ToneSlut trannies.
My preference goes to the Tonesluts.
But if I could do it again with more funding, I would  go for the MM trannies.

My latest build with ToneSluts (These trannies need serious space between them!!!)
Mods: 2x PPIMV footswitchable, Clipper stage bypass footswitchable.

I don have a layout with my mods, but it's simple.

I used the 6,3V to power the relay, not the best thing to do use a seperate transformerwinding if possible,

Rectify this with 4 1N4007 in bridge configuration. put a 100uF 25V on the DC side.
Now put a 6,3 inputjack between the DC and the relay, now you can switch.

Relay must be 6V DPDT.

Look at the Trainwreck pages and you'll see how to put PPIMV Type 2 and Type3 together with
the relay.

IMPORTANT: if you use the 6,3 fillament you can't ground the switch
If you have a separate winding, you can ground the switch.

I have build an Express with two PPiMV, the first sets the volume to an acceptable level
and the second I can footswitch in/out when I use High Gain sounds.
So I can have a louder cleaner  sound and a manageble heavy sound.

I used a PPiMV type 2 from the trainwreck pages and a relay with DPDT to switch a PPIMV type 3
ontop of the first PPIMV.
Works great for me, the amp is used all the time and leaves my Overtone Special collecting dust...

The choke tries to keep the voltage/current up when you hit the poweramp hard.
Because its a coil, it will resist changes by fighting it with induction.

Can't tell you what it'll do sonically...

Hi Steven,

It's a relative cheap and easy mod.
The choke has two wires, that's it...

Dave

Yes, I don't know if the expression has a two voice pitchshifter but my Intellifex does the trick.
I have an old blackface Intellifex I bought for 69 Euro... 
Like it even better than my 3 Eventides I have owned.

Today I ordered parts for a new amp I'm building.
It's based on a Trainwreck Express, hopefully the parts will arrive this week.

How many Reverbs do you need?  Just one that sounds good ;-)

I hate chorus so I don't use it, instead I use pitchshift +4% and -4% this gives a more natural
chorus where the sweepfrequency varies with the played pitch.
2 Voice Chorus are two modulated delay lines, gives a bigger chorus sound.
Original Intellifex has an 8 Voice Chorus...

Programming is easy, just need to scroll a lot. There are PC-editors to make this easier.

I don't use my kleinulator, tone is great.
Output is enough for my band needs, but if you play in a really loud band some more output
from the Intellifex would be better.

I use an Intellifex in the loop.
Mixer dry at 0.0 for normal use and +4.5 for solos works great for me.

Check the wires on the input.
The drawing is a little confusing to look at, you see the input at a certain view that a
mistake is easy to make.

Check if the tip of the jack is connected to the input of V1 and you didn't make a ground
mistake that leads the signal direct to ground.

Also the chassis inputs have connections on each side, but only one side will be active
when you plug-in. So check that you've wired the correct side.

This happened to most of us...

Change the two wires from OT to the two tubes.
That should do the trick.

 

Strange, EMG's are not very dark pickups.