Modulus Amps Princetown Kit Build

spev11

The Princetown (Princeton Reverb) kit just arrived at my shop and I'm beyond excited. I'll document the build/disaster as it unfolds if anyone is interested. I'll also hopefully be making the cabinet for it , its going to be a head so I can use it with the cabs I already have.
Burnt fingers and explosions here I come, like a crap Hollywood blockbuster but without any good looking characters  , more Pinewood studios perhaps

Chris.B

Looking forward to following your progress with the build.

I'm sure you will complete the process with an excellent amp

CarpeDiem

I’m interested in following your build progress.

There are plenty of knowledgeable heroes on the forum that could probably help in the unlikely event that it becomes a disaster movie.

Neilybob

Wow this is going to be fun to follow. 

gdculley

I'm in! I'm on the brink of buying the same kit so I'm interested to see how it goes. Good luck!

JonB

Brilliant your last thread got me looking at an amp build for this winter. Was gonna go for a Princeton then started reading up on the Tweed Deluxe. Last Sunday at the guitar show I saw a pre built Stew Mac Deluxe and figured for the price it was worth it. I won't get the joy of building from scratch but the amount of mods and tweeks I'm looking at should be more than enough. Enjoy it.

spev11

step 1, make a cup of tea and put every in to a storage box, check everything is there and stare at it all panicking mildly.

Chris.B

Remember when you were at school and the teacher said something like "Before you start, read the instructions carefully - twice". I think that fits this situation

Don't forget to enjoy it. 

spev11

Turret boards populated and soldered, mild panic continues but Michael answered the question almost instantly so now i'm stressing over the wiring (and everything else about it all)


I do wish I'd stumped up the extra cash for the Mallory caps for no other reason than they would sit a bit neater on the board. Other than that the first stage has gone well (I know some of the instructions on the web suggest a different way to start but I wanted to confirm i had all the correct caps and resistors and got everything sitting neatly). 
I'll be following the schematic and diagrams on robrobinette.com mostly with a bit of back and fore between TAD, Stewmac and Mojotone, all have instructions and all differ slightly. 
 
 Will be stuffing the transformers and other large bits on the chassis and measuring wires next I think.

Chris.B

Looks like a good start to the project. I hope you're enjoying the build, it looks like a great way to learn a bit more about valve amps.

Keep us posted with progress.

LordOxygen

great project, looking forward to seeing it come together. I've built a couple of the amp maker kits over the last few years, but now his shop is closed I've been looking at the Modulus ones. 

What are the instructions and diagrams like to follow?

spev11

There are no instructions but there is a schematic and there are loads of websites with more than enough info on them. Honestly I had no clue how to follow a schematic but I’m learning as I go. It won’t be quick but I will get there.

spev11

 little bit more progress today, and a few stumbles. I'm still getting to grips with schematics and layouts. I've been using a combination of Stewmacs, Mojotone,TAD and robrobinette.com as my instructions. All of them have different transformers (and some wires on the transformers are different too, mostly assuming 110v or 120v) so I got myself in a state of confusion/panic regarding the power wires going to the fuse and switch. Michael (Modulus Amps) was at the end of an email to sort me out and I'm back on track.
 The ground switch is a dummy part but I may replace that with the NFB mod at some point (gotta get it working as base first).
Day off work tomorrow so will make a start on some of the wiring and probably firing some emails to Michael to drive him crazy.

spev11

  Little more progress today, got the main board wires fitted (not soldered yet) the green wires running from the top are ground wires to the pots so i'll most likely change them to black before I solder em up, only so they arent the same colour as the heater wires (purely cosmetic). As per some of the other builds I have seen  (including Michaels on facebook) have most of the wires under the board so (despite it being a pain to trace) I've done the same where possible, if only so it looks neater.
  I've wired up the power input and the transformer to the switch, I still have a niggling doubt as I have a black wire coming off the power transformer and so far I can't see where it goes, Michael kindly sent me the wiring diagram for the Tweed Deluxe as it uses the same transformer and colour coding (unlike everyone elses on the internet which is US colours) but the Tweed has a standby switch which the black cable goes to (and then on to the board). I'm not using a standby switch so I've wired it up as brown and blue to the fuse/switch/mains cable.

So i've currently got it as per that without the standby switch. My brain only works with linear visual information (or at least having the actual circuit laid out in front of me) then I can follow it along with the schematic so i'll be checking everything as I go and before I solder anything else down.
Not looking forward to soldering the valve sockets, small and fiddly seems to be the order of the day, although I will prebuild the heater cable and do that last I think.

Chris.B

Looks like you are making good progress.  I think we'll be hearing your demonstration next weekend. 

spev11

more progress, mainboard is in, wires soldered, ready to do the sockets in the morning before I start work, looking mental at the moment, will be neater once I start routing the wires (hopefully)

hollywoodrox

spev11 said:

Turret boards populated and soldered, mild panic continues but Michael answered the question almost instantly so now i'm stressing over the wiring (and everything else about it all)


I do wish I'd stumped up the extra cash for the Mallory caps for no other reason than they would sit a bit neater on the board. Other than that the first stage has gone well (I know some of the instructions on the web suggest a different way to start but I wanted to confirm i had all the correct caps and resistors and got everything sitting neatly). 
I'll be following the schematic and diagrams on robrobinette.com mostly with a bit of back and fore between TAD, Stewmac and Mojotone, all have instructions and all differ slightly. 
 
 Will be stuffing the transformers and other large bits on the chassis and measuring wires next I think.

That looks like an excellent start ,well done 

robinbowes

Following with interest - I'm contemplating a Princeton build myself...

gdculley

You're flying through this! Looks great! What is the little separate board at the top left?

robinbowes

gdculley said:

You're flying through this! Looks great! What is the little separate board at the top left?

I'm not @spev11 ;but that's the bias board.

spev11

Yeah bias board, was going to add an adjustable bias pot but I might do that at a later date