5F1 Champ Build (Weber Kit)

[ReginaldBisquet]

Ordered basic kit on September 30, 2011.
Packages arrived on October 12, 2011 . Hot daym!

Here's what arrived in the packages...











The Ted Weber Cabinets Name Badge (shown above) was glued to the front of the grill cloth, but came off very easily without any damage or noticeable markings. The speaker was already installed. Lots of little baggies everywhere in the boxes. Made me feel like a coke dealer!

The components are good. Here's my take on them:

Cabinet: Solid. Looks like pine. Knotty! Great tolex covering job - no loose pieces. Small flat metal feet on bottom and brass screws in the front. From what I can tell, it is indeed finger jointed.
Tube sockets: ceramic. Nice!
Wire: solid and stiff. Much like my... ehhh.... forearm.
Potentiometer: Alpha.
Jacks: Cheap. Very very cheap. I only know this from working on an older MI Audio pedal where wafers in the the input jacks (literally) crumbled apart. These jacks look to be of the same type/build.
Transformers: More than meets... ehh, sorry. Both transformers are solid and Weber brands.
Board: solid. The kit also included the traditional brass plate!

NEXT: Shopped around at Hoffman Amps, Marsh Amps and Watts Tube Audio to source out the remaining parts: capacitors, resistors, Switchcraft jacks, tubes... and... what the heck, a Classictone output transformer and a cute green knob with matching jewel lamp cover.

I also plan on installing a 1/4" jack for the speaker connection instead of wiring directed to the circuit. Perhaps foolish? But then again, that's how Momma raised me.

Will post again when I have the additional parts delivered.

[big mike]

Looking foreward to seeing your build. Def upgrade the jacks if they're questionable.

[guitarcapo]

Mine has a bightness cap switch and a switch that changes the cathode cap on V1. 10" speaker and no nfb loop

[ReginaldBisquet]

I'm going to stick with Ted Weber's schematic for the build except that I am using 1 watt carbon film resistors instead of 1/2 watt carbon comp. Reason: I have heard that the carbon film resistors are sturdier (more stable)... which can be a good thing considering my neanderthal approach to soldering.

The capacitors are Sprague Atoms and a Mallory for C1 & C2.

I should have taken the back off the amp cabinet so everyone could see that a 10" speaker would fit (with the right baffle) with no issue in this cabinet. When peering inside, I considered changing out the baffle... but if I can build the Champ without burning down the house, then my next build will be a Princeton Reverb with a 10" speaker.

[guitarcapo]

Carbon comp gets a bad rep for adding hiss to the signal if used in the early gain stages and also being sometimes off spec. They are supposed to have a slight "varistor" quality to them under large voltages, though, so they might actually be a good choice in high voltage applications like around the phase inverter and as plate resistors to power tubes.
For quality I would pick metal film resistors everywhere though.
I don't know if cap types make that much difference in sound, huge arguments over that...but I like the look of foil and oil myself.

Have you thought about adding a choke instead of that huge 5 watt "chalk chunk" resistor?
You might also want to add a 25uF/25 volt cap across the V1 cathode resistor (ala the 5E1 circuit) to see if you like it.
Most original "5F1" Champs had that cap even though it's not on the official schematic. Either the change was never implemented or Fender used older boards...but it's worth considering. Personally I like the extra brightness and gain it provides.

[Mattbedrock]

Keep us posted!
Love a good build thread!

[ReginaldBisquet]

Most of the parts have arrived...



... just need a couple more tubes and the output transformer. I'll start populating the board this weekend.

Have you thought about adding a choke instead of that huge 5 watt "chalk chunk" resistor?
You might also want to add a 25uF/25 volt cap across the V1 cathode resistor (ala the 5E1 circuit) to see if you like it.
Most original "5F1" Champs had that cap even though it's not on the official schematic. Either the change was never implemented or Fender used older boards...but it's worth considering. Personally I like the extra brightness and gain it provides.

Quite a while ago, I considered adding a choke to my Vox Night Train, but several tech heads dissuaded me from doing so saying it was in the territory of diminished returns. The consensus seems to be that chokes are handy for amps rated 30 watts and higher.

I looked up the 25uF/25 volt cap idea you mentioned. Not sure I want "extra" brightness from this amp - but it's an easy mod if I want to try it. For now, I just want to build the thing without having to explain to my wife that I burned down the house.

[blam]

neat. I'm kind of tempted to try one of these. im surprised the cabinet isn't finger/box jointed.

[ReginaldBisquet]

Originally Posted by blam

neat. I'm kind of tempted to try one of these. im surprised the cabinet isn't finger/box jointed.

I was too... but then I looked closer and found that the cabinet is indeed finger jointed. It's hard to tell from the photo.

[blam]

oh, that's good to know.

maybe in the new year I'll pick one of these kits up.

[Casey4s]

Good luck with the build. Keep posting pics as you go. Thanx

[ReginaldBisquet]

Sleep is over-rated! I went ahead and populated the board last night. Once I got started, it was a quick process.



I moved the 5 w chalk resistor so that it's elevated and a little further away from the capacitors as I don't want the heat from the resistor to become an issue.

Some weird issues:

1. The indicator jewel lamp that comes with the kit is a Chinese made bayonet -style bulb holder. If you want to order a replacement jewel lens, you will need to order a Chinese made lens (narrower threads) or a new indicator lamp bulb holder.

2. I thought the board was supposed to be secured at two places on the chassis. However, this board only lines up with one hole on the chassis. Weirdness.

3. I think the next time I make a circuit board, I'll try out the turret system as the eyelet boards can get a little cramped with multiple wires coming and going.

[Hulakatt]

Double check that the jewel light cover you ordered works with the light housing. When I built my weber 5f1, the housing was just different enough that I couldn't swap the jewels. Overall though I love mine 3 years down the road!

[ReginaldBisquet]

ISSUES AND TRAGEDY

While building this amp, I've run across a number of issues that makes me doubt using Weber for their kits. My only other amp kit building experience comes from Ceriatone. See:

http://www.thegearpage.net/board/sho...d.php?t=843360

The Ceriatone kit came with lots of high quality components and plenty of photos on their site to help inexperienced builders (like me).

Anyway, some more notes:

The green wire that I used on the board is supposed to be used for the filaments. It's a heavier gauge wire than the red and yellow wires. Thankfully, it's a small chassis and there's plenty of wire left.

The black & white wires that came with the kit are for the speaker connection.

The mounting holes of the eyelet board did not line up with the mounting holes in the chassis. So I had to trim and 1/2" off one side so it would fit.

Otherwise... all was going well until I decided to plug in the 6V6 into the tube socket:



It was a super tight fit, which I thought was very odd. When I pulled the tube out, the center pin had come off! CRAP! I tried out a 6L6 tube I had sitting around... and now the sockets are loose as the tube slides in and out too freely.

Ugh! Any insight as to why this occurred?

[big mike]

Tube is still good, don't sweat it. Draw a line on the tube where the indicator would be, and draw the same line on tjhe tube socket and proceed.

This really isn't Weber's fault, some 6V6s and even other tubes, the centering pin can be different sizes. Also the tube's metal pins can vary (JJ is notorious for that).

I use beldon for all my power tube sockets because of that (michalex material) but it's no biggie really.

My only complaint with your kit is the way the cabinet appears to be jointed.

Looking good with your build! These little hiccup's teach us things along the way.