18 watt post 17

Hope I got the number right. Went to Home Depot yesterday and got a 10 foot 10" white pine board. Very tight grain, so it should do nicely. Will work on cutting and joining it this weekend, if not before.
Keep you posted.
k

18 watt post 16

Took the 18 watt to praise band practice tonight. Worked very well. Hooked up my dd3 delay and a DS1 distortion to use as a boost.. (no drive). Was able to control the drive and tone of the amp by the guitar vol controls. Roll it off...it cleans up, cut it back up and it drives like crazy. Nice....exactly what i wanted. And very touch responsive.
Working on the head cab now. Hope to have it done in a couple weeks.
Will keep ya posted.
Kirk

18 Watt post 14

Well, I couldn't leave well enough alone. I noticed that the low gain channel has a little bit of buzz in it, so I have decided to rewire the input section again. I went and got some smaller shielded coax..was orginally done with a piece of guitar cable...which is very bulky. We shall see how this comes out. I think the noise is from the fact the cabling i used before is stranded and is under some strain with the solder joint being unsupported..so every time I poke it, it crackles..or when is vibrated by music...does same..albet very faintly..still I want it gone.
Will see how it goes.
Let you know.
kirk

18 watt post 13

I got rid of the noise. Took me a couple days of poking around, but I got it. I reflowed the solder on the board. Didn't fix it. I reflowed the input jacks and that didn't fix it. I went and got a chopstick and started poking...found it. The wire going from the input jack to the first preamp tube for the high gain channel was not soldered well...it went zzzzz when i pushed on it. I unsoldered and resoldered the wire and now it sounds ever better than before, more gain and better highs.
Now, back to chopsticking. Why use a chopstick or other similar object? Electricity kills. The voltages in the amp I have been building are over 300v dc...more than enough to kill you. Don't think about using a pencil either...graphite in pencil lead is a conductor of electricity. Chopsticks, wooden dowels, a plasitc rod...anything that won't conduct will work.
Have karate tonight. When I get back I plan to record the amp and post the clip and some new photos.
k

18 watt post 12

I could not stand it. I got up this morning and went over the layout in about 15 min. and made sure my ei's were dotted and my tee's were crossed. Went and got my mimi mass (attinuator/dummy load)...flipped the 18 watter upside down and plugged ac power and the MM in. NO tubes-flipped the switch. Measured AC and heater voltages...350 vac to the rect pins (yeah thats high, but no load form tube heaters)...checked heaters on all sockets..hmmm..looks good so far. Popped in the EZ81 rectifyer tube...Voltages to the PT and pretube sockets look good. Put in the el84s...still looks good. Put in the pres...all voltages look good!
Hooked up a speaker and with no guitar...cut the vol up...a little faint ac humm...ok, good so far...plugged in a guitar... 1/2 up..jangle jangle...I'm liken it!....wide open.....HOLY COW!
I started playing "ALL RIGHT NOW" ...and the tone was so there...backed the vol off and it just purrs...OH YEAH baby...das what I'm talking about. There is a little overring (fuzz after notes)..probably a cold solder joint...will shorten a couple wires and reflow the joints in the morning..but all I got to say is....YES....that is how a Marshall 18 is supposed to sound...at least as far as the internet recording I have heard of them.....BINGO....
I am in narvana right now...(will get back to narvana after I go cook some hotdogs and watch some fireworks...happy 4th all.)....
MORE LATER....with sound clips.
kw

18 watt Post 11

Cool, got the parts in from AES and finished wiring up the amp tonight....here is what it looks like from the bottom side.

Tomorrow night I will take a copy of the layout and highlighter and go over everything one more time. Friday I plan to test it...hopefully no fireworks. Hope to have a good report on it Friday, maybe even a sound clip.

After it is successfully working and debugged I will begin cabinet construction. Thinking pine, finger joined....with a nice poly finish. I may do something special with the front panel, don't know yet....more on that later.

Bedtime....Later.

Kirk

18 watt Post 8

Back after a few days am I! Talk like Yoda I can!
Wire from ApexJr came in today (600v teflon wire- 5 different colors). Last night after karate I went and finally drilled and turreted the board for my 18 watt. Tonight I plan to populate the board and I have wire, so I might even mount the tranys, hook up the heater wires and mount the standoffs...who knows...it all depends on how froggy I feel at the time. Above all...we are making progress. It looks more and more like an amp every time I fool with it.
May get Steveo to help...He and Becky are coming over and we gonna get our grill on....hope to have some pics tomorrow of something amp looking.
more later....
kirk

Firefly Modifications

One mod I wanted to do to the FireFly (1.5 watt amp I built) was to put a bright switch on it. The board I used had a place for the mod so when I was ordering stuff for my 18 watt build I order a 120pf and 220pf mica cap. I went to radio shack and got a three way (on off on) and wired it up. Seems to have helped some with high end..we shall see...didn't have a lot of time to fool with it yesterday...but i will this week.
Having the swim meet this weekend didn't allow me to work on the 18 watt any..so I plan to start back on that tonight or tomorrow night. Am working on the board now...wire is on the way. Should be ready to see if it will make noise by next weekend.
We shall see.

18 watt post 7

Got the layout drawn tonight, hope it works, will drill and turret the board tomorrow.
Put the grommets on the chassis, along with the tube sockets. I beginning to LOOK like an amp. I even stuck a coupel tubes in it to see how it looked....pretty spiffy.
Hope to have board turreted tomorrow and begin populating it. Still no wire...need to get on that asap. But if I can get the other components on the board by Saturday i will feel like I have accomplished something this week. Next week I should be able to solder in the wires and go through Paul Ruby of Ruby amps startup guide.
Ruby's start up guide is a MUST. It walks you through measuring voltages and such as you add sections to the amp. It basically keeps you from frying the amp. Good stuff...google it.

18 watt Post 6

My kingdom for some tape!! I have a daughter (3) who loves tape. If she finds a roll...it's a goner.
And now my problem..I have all my parts sans wire, to build my 18 watter. I need to lay out the board so I can mark it and drill holes for the turrets. The plan was to tape components to the board as I work across it, mark it and remove them. But, thanks to my daughter I have no tape. Found what was left of the last of it in her room. The tape was wrapped around several barbie dolls and dora dolls...so tomorrow I shall purchase some more take and tomorrow evening lay it out. I did manage to put the IEC power module, pots, and neon power indicator light on the chassis, finger tight. Need some small bolts, nuts and washers to put the tube sockets onto the chassis...will pick those up tomorrow at lunch from Home Depot...I am sure they have Scotch tape too...if not, Wally World is next door. So much for getting a lot done, but I got a little done. Each step is one step closer. Board is the big hurdle, once I get it done it will only be a matter of an hour or so of work. Will order wire tomorrow, ApexJr doesn't have an online purchase system...have to call.
k

18 watt Post 5

Ordering wire today. Have pretty much everything else wrapped up as far as coming. May pick up another amp handle from somewhere. Have a cheap one...but we ain't to cab building yet. Deburred the chassis, got some screws for the standoffs and lock washers to go with them. Did forget to order hole covers for the 6v6 holes. Don't know if I will, I might just play the amp like it is for a while, and then order some 8 pin sockets and put in a differenct tail resistor and cathode bias resistor ( I think that is the two i change out)...and be able to use both el84s and 6v6s in the amp..not at the same time though).
6V6's have a mellower sound, about the same power, less chimey. If i think the amp is too bright...might be a good option. Have heard some 6v6 Lite IIb's on the web, some sound good, some don't. But that is the same with el84 versions too...you sometimes have to tweek them to get them to do what you want by changing values of resistors and caps...remember i am new at this, so i will probably screw it up once or twice.
Enough of that....have a great day.
k

18 watt post 4

Today I go to Home Depot. I plan to get a deburring tool, some screws, lock washers. some other misc. stuff. Since I don't have a board mask or drill plan, I think I will go ahead and order my stuff from Mouser and Antique Audio so I can lay the caps (bigger pieces) on the board to get an idea of how much space to leave.
I need the deburring tool to clean up some of the edges on my chassis...they are pretty sharp and i really have no desire to get a cut.
More later.

18 Watt Post 3

Postman came today and brought me a box of goodies! What came in today you ask?
Board material, turret lugs, spst switches for power and standby, standoffs, washers, ground rings, chicken head knobs (my favorite), rubber grommets, a turret staking tool, an impedance selector switch. switchcraft jacks for input and speakers. Well I felt like a kid in a candy store.
Will work on drawing off a board mask so i can drill and stake the turrets next weekend. Will post pics when i get it done. Once completed I will order my other board componentes and wire.
Watch for board pics soon.
kw

18 watter post 2

Here is my 18 watt Lite IIb chassis with the transformers sitting on top of it as they will be later bolted down. Later tonight I plan to go online and order my board, turrets, standoffs and an impedance selector switch from a vendor. I will then begin building my board. Once completed I will order the electronic parts to populate the board with. Thanks to Dockery amps for the prompt service.

Watch for pics of the board as I get it started. My hopes are that documenting all this will possibly help someone else who is thinking about or doing the same thing.

Have a great evening.

k