Marshall 18W Build Log *FINAL PICTURES ADDED!* 56K!

[wassupdoc]

*update*

Update time

So I got the first stage of the build almost finished at the weekend (in the short time I had while my girlfriend was out ). The PP-18 is almost ready to be fired up I'm really happy with how the wiring turned out!

First power on (no valves) ANNNNNNNN Success! All the internal voltages match up on this particular test Time for the valves!

PROBLEM :dammit:

I finally got around to making the measurements for the PP-18 with the valves installed, turns out my mains voltage is over the legal limit I'm reading 256V AC so it's affecting my internal readings quite a lot! It's going to take me awhile to work out the new desired internal voltages I should be getting... :banghead:
Barry from Ampmaker said I may have to tame it with something called a zener diode??

Also forgot to say I received a rather lovely electric shock while measuring the valve-in internal voltages! But ah well :bornleetsign: Can't say it didn't scare me (or fooking hurt!) but I've got some lovely burnt pinhole entry and exit wounds! (which i used to work out that i must of caught my arm on the chassis - accidentally grounding myself :banghead: - and exiting through my knee to the floor )

 

[wassupdoc]

Updates have kinda ground to a halt at the moment guys, sorry about that! I finished the first amp, took all the measurements, fired it up! Annnnnnnd... Nothing. Diddly freaking squat.
Power/standby light comes on, speaker makes noise if I touch the audio circuit inside but plug a guitar in and sweet FA happens I continuity tested every connection made in the entire amplifier and they are all perfect - leaving only a faulty component :banghead:
Barry's being very very helpful as usual though Asked me to send him macro shots of everything in the amp and he's going to diagnose anything I might of missed! (I have a feeling the resistor he send me that he forgot the first time is the wrong value, can anyone read the blue resistor because I can NOT figure it out for the life of me!)

Stick around!

 

[SPS]

Ah that's a shame

 

[wassupdoc]

Ah that's a shame

Shouldn't be too long out of the loop dude ^.^ I'm a perfectionist, so I'll throw everything at it to get it sorted

 

[tinytomlogan]

Voltage wise....... why not plug it into a UPS?

 

[wassupdoc]

Voltage wise....... why not plug it into a UPS?

For building an amp and home use that's a great idea dude! But it turns out it was just a rather hot day on the grid Reading around 243V now - well within the normal limits

I guess the other argument is that it has to be practical, every gig you go to will have a different voltage, sometimes hotter sometimes (worst case) lower - building an amp you have to make it resilient to voltage changes You're right though the perfect scenario would be plugging it into a UPS but that would mean lugging one around to every gig And after sticking 28U of batteries in a server rack this week I don't fancy seeing one in a long time haha! :rollinglaugh:

It's nice to see so many familiar faces on OC3D have interests outside PCs and gaming ect

Thanks for the interest Guv! - Although you always put lots of very expensive ideas into my head :slap:

 

[wassupdoc]

IT'S ALIVE!!!! *Frankenstein laugh*

So I bought some LEDs to stick under the tube sockets when I finished the amp - figured I may as well stick them in now :

*hummmmmmmmmmm* ... Wait what??!!

So yes it seems to be on... because I stuck some lights in...

The tubes started glowing

Obligatory night shot:

Don't ask me how... I have just as much of an idea as you

 

[SPS]

Ha, sweet! I could only imagine the original solder points were dodgy?

 

[wassupdoc]

Ha, sweet! I could only imagine the original solder points were dodgy?

I don't know! I continuity tested them all It is thunderously loud, much louder than my 100W Blackstar

 

[wassupdoc]

Nice Big Update

Nice big update for you guys today

I thought I should build the VVR kit from Hall Amplification (http://www.hallamplification.com/main.html?src=/#2,2) before the major conversion - It alters the power section so I want to KNOW it works before I start straying out of the supported alterations (Don't have any pictures of it in progress - You need all the hands you can get for little PCBs!)

Not bad for my first PCB ever

Looks nice and neat

The purpose of this potentiometer is to reduce/increase the voltage over the tubes - so you can dial in a nice sound, then turn the watts down so the sound guy DOESN'T want to kill you

However I decided to install it over the whole amp by interupting the B+ rail before the standby switch - I should get a little more crunch this way and be a little quieter (hum-wise)

No room on the front panel with all the controls so out comes the drill! *squeaky bum time!*

*Drill dies* -.-
*Takes out tiny files*

All mounted!

Inside The excess power is dispersed partly to ground (via the black wire to the grounding nut) and partly as heat via a Toshiba Mosfet, this should help preserve the tone at lower volumes

The VVR board/pot

Notice the MOSFET - It normally mounts to the PCB but I had to relocate it due to the way I was forced to mount it, this way it has a nice big chunk of metal to act as a heatsink too

I managed to test it out last night and it all works brilliantly - it loves taking pedals too! So tonight the big modifications are coming

 

[SuB]

You're making me jealous... and a jealous Sub usually spends more than he can afford...

 

[wassupdoc]

You're making me jealous... and a jealous Sub usually spends more than he can afford...

Well I'm always open for commissions hehe - I know what you mean though!

 

[wassupdoc]

Teaser

Just a wee teaser shot for you guys

As for the amp, everything is working flawlessly The electronics are finished as far as I'm concerned

STAY TUNED!

 

[wassupdoc]

Oh look... I'll just leave this here

 

[Dedwoods42]

You've done a really lovely job of that! Housing looks gorgeous too

 

[wassupdoc]

You've done a really lovely job of that! Housing looks gorgeous too

Thank you sir I've been playing it ghetto style for a week or so now and it's beautiful

The blackstar is a very different amp They both have their good and bad traits - as do all amps ^.^

 

[Dedwoods42]

Haha, gotcha Every time I go into the big PMT in Birmingham I have to promise myself I won't consider finance... Too many gorgeous Blackstar & Orange amps...

Looking forward to seeing the continuation of this build!

 

[wassupdoc]

Haha, gotcha Every time I go into the big PMT in Birmingham I have to promise myself I won't consider finance... Too many gorgeous Blackstar & Orange amps...

Looking forward to seeing the continuation of this build!

I was in dawsons I got a beautiful Orange closed back 2x12 with celestion vintage 30's and the ID100 head on 0% finance I'd just got a job haha so I was feeling loaded xD

 

[wassupdoc]

*final pictures*

BIG 15k warning!!

I finally finished everything today and had the time to take some nice photos in the daylight The project's been a lot longer than I expected, mostly due to things I never foresaw being needed to be done, like having to redo all the internal supports on the housing -.- (won't be getting the next one from him). I now know how long it's going to take so I should be able to build one in a couple of days in future This was a tester to see how hard it would be to start up a small amp business - I think I might go ahead and make a run of 5 if I get some interest, building from scratch this time, I've been looking at suppliers for components

Enjoy the pictures guys and thanks for your prolonged interest! ^.^

I'll get a proper video set up as soon as I get chance - she's certainly a beaut

Thanks again guys Keep your eyes out for the video!

 

[Feronix]

That looks gooooooood

I want it!