Wisconsin Crack

[Mak33]

Built the Crack amplifier (or should I say 'started building'  ) in Fall of 2010.  This is my first time soldering and first time working this in-depth with electricity and electronics.

I'll post more pictures when I find some of the earlier build, but this is current state of the belly up.  I know it doesn't look pretty, and I have no desire to finish the chassis.  I may stain the wood when I get around to it...

AMP: Was stock for about a year.  Great for a beginner getting into some serious audio and recommended by a friend/co-worker.

Minor upgrades begin (though not nearly as extensive as most Crack builders & owners)
POT:  I grabbed a Blue Alps potentiometer in Fall of 2011.  In addition to the pot, I grabbed an aluminum volume knob from PC.
TUBES:  A few months after that, I found a decent RCA 6AS7G power tube to give me some variation from the Tung-Sol 6080 that Doc included in the kit.  Also picked up a different input tube at low cost.
SPEEDBALL:  In early 2012, I bought the speed ball upgrade just before the price increase.
CAPS:  Axon True Caps... 51uF x 4.  Then I put a 2.2 uF as a bypass(?)... All of this is really just following other people's builds and not paying too much attention to the circuit.  I know... bad practice and somewhat risky, but I electricity doesn't come easy to me.

I'd like to keep upgrading parts, but that will come with time.  Currently I'm very content with how little of money I purchased the amp and upgrades for and how beautiful the output is.

UPDATE (6/23/12):

Was getting anxious to get the capacitors off of the ground from the adhesive cable tie mounts not bonding well when the chassis gets hot.  Found some #10 bolts and nuts (1/2" length, but wanted 1/4") and bolted the mounts to the underside.  The cable ties were not easy threading through the mounts, now with a screw there.  Would have been easier with a smaller bolt/nut.  I threw the aluminum knob on again too.  Overall it wasn't too bad, but I wish I used a different mounting system to make the job easier.  I'm borrowing the interconnects from a friend, who also sold me the KECES DA-151 DAC (USB) at a generous price.

 

[Laudanum]

That'll work!  That's about all Ive done to mine with the exception of installing 100uf Mundorf MKP's instead of parallel Axons.  I also installed a 2.2 uf mundorf bypass to last ps cap.  Alpine Blue Velvet which tracks great at all volumes and doesnt sound colored at all to me ... hard to beat for $14.  I still havent found an aftermarket knob I like.  Got one from overseas but too big.  I installed speedball a month or two after the build.  And only other thing I think I did differently was a mills resistor.  I have rolled quite a few tubes.  Right now using a 5998 and a Sylvania 12BH7.  It's been about a year, I couldnt be more pleased.  Great amp and a load of fun.

You could shorten up the leads on the bypass cap.  Supposedly, the shorter the leads the better but in all honesty, I highly doubt I would hear a difference. 

Looks good to me 

 

[Grainger49]

Looks like good and tidy wiring to me.

And you probably know, I'm a big fan of large caps.

 

[Mak33]

Thank you for the comments.

The leads on the bypass cap are definitely long (didn't cut them).  I was going to shorten them up, but like you said, I really doubt I would hear a difference.  Next time when I am looking for something to do, I'll turn that thing over and shorten it up.  I'm also noticing that the mounting squares for the caps/cable ties aren't holding the greatest.  While drilling a hole for a screw is an option, I may just try to find adhesive that bonds well at higher temps.  I always knew that the plate gets warm, but mine gets hot.  It has plenty of room for air, but it gets to the point where my fingers can barely stand the heat... maybe a low pain tolerance.

 

[Laudanum]

Thank you for the comments.

The leads on the bypass cap are definitely long (didn't cut them).  I was going to shorten them up, but like you said, I really doubt I would hear a difference.  Next time when I am looking for something to do, I'll turn that thing over and shorten it up.  I'm also noticing that the mounting squares for the caps/cable ties aren't holding the greatest.  While drilling a hole for a screw is an option, I may just try to find adhesive that bonds well at higher temps.  I always knew that the plate gets warm, but mine gets hot.  It has plenty of room for air, but it gets to the point where my fingers can barely stand the heat... maybe a low pain tolerance.

The metal base 6080 adds to the heat.  They generally run cooler with the phenolic base tubes and maybe even cooler with the larger ST shape tubes (6AS7).  But hot is not abnormal.  
I bit the bullet and drilled mounting screws for the tie-strap hold downs.   The hold downs I preferred actually have two mounting holes each and I used two per capacitor.  I used small (#4 I think) stainless  button head allen screws and made sure I lined them up straight and symmetrical between both sides.  I also changed the some of the other through-the-plate screws to the same type.   It turned out fine but definitely overkill.  I probably could have gotten away with a single tie strap mount per cap and a single screw.   I would think that scuffing up the bottom of the hold down and using a good epoxy may hold for good while.  Maybe even silicone sealant/adhesive if allowed to overflow into the center screw hole area of the hold down.  But the screws are fail safe.  You just have to be willing to drill the top plate.  

There is a photo of mine showing the screws


http://www.bottlehead.com/smf/index.php/topic,2188.0.html

 

[Mak33]

Thank you for the comments.

The leads on the bypass cap are definitely long (didn't cut them).  I was going to shorten them up, but like you said, I really doubt I would hear a difference.  Next time when I am looking for something to do, I'll turn that thing over and shorten it up.  I'm also noticing that the mounting squares for the caps/cable ties aren't holding the greatest.  While drilling a hole for a screw is an option, I may just try to find adhesive that bonds well at higher temps.  I always knew that the plate gets warm, but mine gets hot.  It has plenty of room for air, but it gets to the point where my fingers can barely stand the heat... maybe a low pain tolerance.

The metal base 6080 adds to the heat.  They generally run cooler with the phenolic base tubes and maybe even cooler with the larger ST shape tubes (6AS7).  But hot is not abnormal.  
I bit the bullet and drilled mounting screws for the tie-strap hold downs.   The hold downs I preferred actually have two mounting holes each and I used two per capacitor.  I used small (#4 I think) stainless  button head allen screws and made sure I lined them up straight and symmetrical between both sides.  I also changed the some of the other through-the-plate screws to the same type.   It turned out fine but definitely overkill.  I probably could have gotten away with a single tie strap mount per cap and a single screw.   I would think that scuffing up the bottom of the hold down and using a good epoxy may hold for good while.  Maybe even silicone sealant/adhesive if allowed to overflow into the center screw hole area of the hold down.  But the screws are fail safe.  You just have to be willing to drill the top plate.  

There is a photo of mine showing the screws


http://www.bottlehead.com/smf/index.php/topic,2188.0.html

Appreciate the photos and words of wisdom.  I may have to travel down this route... one of the mounting squares isn't holding.  I may try another one to see if it will stay, but I will look for another solution if it doesn't do the trick.

Thanks!