12XXX Build 05/2010

[Strat78]

How is the build going? I'm going to get a 68 kit this week and was wondering about the difference between Georges 68 replica and the 68 parts package. I like the ceramic caps on George's build (white arrows), are these better? Also I was wondering why he used two capacitors instead of one big one (see green arrows). Any other advise on variations in components that I should specify before ordering?

[Roe]

How is the build going? I'm going to get a 68 kit this week and was wondering about the difference between Georges 68 replica and the 68 parts package. I like the ceramic caps on George's build (white arrows), are these better? Also I was wondering why he used two capacitors instead of one big one (see green arrows). Any other advise on variations in components that I should specify before ordering?

george uses two f&t 16uf caps instead of a dual f&t 33uf. you will hardly notice the difference. personally I prefer two 22uf BCs (george also use those).

ceramic caps sound different from silver micas. marshall used both types in the 60s. these affect the tone quite a bit. experiment a little and see what you like

also, george uses premium/vintage sozos

[vanhalen5150]

Yeah, I should be done by weeks end. I'll post a clip as soon as I get things presentable. I just used what George sent in the specs kit. Can always change later. Im not sure about the 1 or 2 cap version. You'll also notice George solderd the lead wires to the bottom of the board while mine come up through and attach above. I only did this so I wouldnt have to take the board out later if I need to change/mod anything.
Great kit to build. The learning curve is huge.

[Strat78]

How is the build going? I'm going to get a 68 kit this week and was wondering about the difference between Georges 68 replica and the 68 parts package. I like the ceramic caps on George's build (white arrows), are these better? Also I was wondering why he used two capacitors instead of one big one (see green arrows). Any other advise on variations in components that I should specify before ordering?

george uses two f&t 16uf caps instead of a dual f&t 33uf. you will hardly notice the difference. personally I prefer two 22uf BCs (george also use those).

ceramic caps sound different from silver micas. marshall used both types in the 60s. these affect the tone quite a bit. experiment a little and see what you like

also, george uses premium/vintage sozos

Thank you Roe! I'll try to get up to speed before I ask too many dumb questions, but hopefully this will be allot of fun! The 22uf's give a little more head room and less early breakup? The premium/vintage sozos seem intriguing but I did not see them here at metro, where? I'll just grab some extra ceramics caps with the kit and experiment (thanks again), what's are the values on those ceramic caps?

[Strat78]

Yeah, I should be done by weeks end. I'll post a clip as soon as I get things presentable. I just used what George sent in the specs kit. Can always change later. Im not sure about the 1 or 2 cap version. You'll also notice George solderd the lead wires to the bottom of the board while mine come up through and attach above. I only did this so I wouldnt have to take the board out later if I need to change/mod anything.
Great kit to build. The learning curve is huge.

Can't wait to hear it!

[vh junkie]

Yes, I would like to know the source for those ceramic caps as well. I don't see those in the Metro store.

The dual caps are supposed to prevent intermingling of currents between the first and second stages. I think it might be better if the weren't grounded at the same place though.

Might consider going to NOS mustards. Seems like that's what you see in Rockstah's stuff. I just put a set in one of my amps, about $180; while vintage sozo's are about $60 (any one need a nicely broken in set?).

Other stuff to consider is what kind of transformers do you like.

I'll post a spreadsheet I adapted from one George posted. It let's you figure out pricing for only the things you need. For instance I already have two head cases. Might not want to get another one right away.

The attachment 12 SERIES KIT.xls is no longer available

Sorry, it doesn't have all the prices; and a lot of the missing parts are in this kit:
http://metroamp.com/store/index.php?mai ... cts_id=351

[Roe]

How is the build going? I'm going to get a 68 kit this week and was wondering about the difference between Georges 68 replica and the 68 parts package. I like the ceramic caps on George's build (white arrows), are these better? Also I was wondering why he used two capacitors instead of one big one (see green arrows). Any other advise on variations in components that I should specify before ordering?

george uses two f&t 16uf caps instead of a dual f&t 33uf. you will hardly notice the difference. personally I prefer two 22uf BCs (george also use those).

ceramic caps sound different from silver micas. marshall used both types in the 60s. these affect the tone quite a bit. experiment a little and see what you like

also, george uses premium/vintage sozos

Thank you Roe! I'll try to get up to speed before I ask too many dumb questions, but hopefully this will be allot of fun! The 22uf's give a little more head room and less early breakup? The premium/vintage sozos seem intriguing but I did not see them here at metro, where? I'll just grab some extra ceramics caps with the kit and experiment (thanks again), what's are the values on those ceramic caps?

the value (16 or 22) isn't really important. the type of cap is more important,

contact sozo if you want those caps

I guess the value is the same (500 or 560pr for mixer and 470 or 500 for eq)

[vanhalen5150]

I'll build the stock first, and then change. Do clips of both. Is there a big difference? Only way to tell IMO.

The caps are 560(2) and 47.

[Tone Slinger]

I finally got the time to install the three trannies. My kit has the yellow sozo's, not sure if they are the 'vintage model or not. I have the f and t dual 33uf filter can. I recall my kit did come with some nos allen bradley cc resistors. I echo vanhalen5150 here, this build is a huge learning experience. Luckily I have some electronics (mainly pedal building) experience.

I also am gonna build mine as it came first and experiment later. I got the Lar/Mar ppimv to use until I can swing an Aracom attenuator. I also got the 'zero loss' fx loop, because I love using an old Boss digital reverb/delay pedal that I have to get a more 'polished' album type vibe to my sound (like VH1). I will have to drill 2 holes in the chassis to do this, and this damn chassis is thick and hard !

My biggest decision concerning my 12xxx build is this, which ot tubes should I install,first I got EH el-34's and EH 6ca7's.(EH tubes have done me better than other's) , though I sold my last Marshall (800 series) 4 years ago.

[Strat78]

Just put in my order! HELP

[vanhalen5150]

Just put in my order! HELP

No turning back now dude.

[vanhalen5150]

Hooked up the circuit board last night, and preamp tubes. Re soldered a few things, and still need to redo a few more things. Pots are left, and biasing this weekend.
I spoke to Roy Blankenship on the cap orientation thing. He was quite reasuring that it does not matter if your installing new caps. I left mine all the same way, Ill take his word on that, since he's made a few amps in the day.
Still need to clean up a few soldering joints.

[vanhalen5150]

I'd also suggest to anyone if your mounting everything on top of the board as I did to install all the wiring and mount the board first, then install components. I assembled the board separate, thinking this was easier. It's not because you still have to thread many things up throught around the components.

[Tone Slinger]

Great strat78, hopefully here in the next few months we can swap spec idea's concerning these 12xxx builds (at least Vanhalen5150, you and me, or anyone else) I wonder how consistant the sound is gonna be from kit to kit, what speakers are being used, tubes, etc.

Vanhalen5150, what is that red looking solder ? Your build looks nice, sure wish I was that far along on mine.

[vanhalen5150]

Great strat78, hopefully here in the next few months we can swap spec idea's concerning these 12xxx builds (at least Vanhalen5150, you and me, or anyone else) I wonder how consistant the sound is gonna be from kit to kit, what speakers are being used, tubes, etc.

Vanhalen5150, what is that red looking solder ? Your build looks nice, sure wish I was that far along on mine.

It's just a red sharpie. I checked all my soldering joints for continuity with a multimeter. If they check out, I color them red. I fiqure may as well know if they work before turning the thing on.

Plus it looks pretty.