[jjinh]

Quote:

I have had this kit sitting for a year now......finally started the wiring up today because a buddy motivated me to finish this project & offered assistance. Hopefully the rest will be done tomorrow.

 
Hey, I've also had my kit for >1 year! I'm just lazy but I had an hour to spare so I soldered in all that stuff there in the pic below.
 

 
 

 

[Armaegis]

Quote:

 
From the Bottlehead website, "max output about 10V into a 300 ohm load." I bet if you e-mailed them they'd tell you the milliwatts.

P = V^2/R, or roughly a third a watt in this case.

 

[sennheiserhd485]

Quote:

P = V^2/R, or roughly a third a watt in this case.

Ick. So, 333 mW?
 

 

[igotyofire]

 
Quote:

 
Hey, I've also had my kit for >1 year! I'm just lazy but I had an hour to spare so I soldered in all that stuff there in the pic below.
 

 
 

Good luck bro! I just finished mine tonight & unless you have some better amp's lying around you will be kicking yourself for waiting so long for your fix! This thing is sweet & is only the 2nd amp I have built(CMOY first for experience). I did all the soldering & my buddy cut up all the wires for me. Only had 1 cold solder join with the LED's that was probably the one of the hardest parts since everything was so tiny. Everything voltage tested perfectly fine with various amounts off to small percentages. Now I was ready to throw my HD600's away as my Maverick D1 wasn't doing them any justice. My 600ohm Dt880's far exceeded them & the HD600s sounded far better on Ray Samaual's premier amp on a balanced setup that I once heard which was the whole reason i purchased the HD600s. Well the Crack amp & the HD600s was a match made in heaven. It makes the DT880's almost seem useless in certain circumstances in the very short amount of listening Ive done. Ofcourse its all genre specific but I will have to do some more listening & critique after I can get some more time in!  So thats my two cents for now! Here is the finished product below
 

 

 

[captouch]

Pictures of my recent build. . .
 
Underside, currently stock.

 
 
Top looks black, but isn't really.  It's Rustoleum Universal Metallic Oil-Rubbed Bronze.  Pretty easy to apply - satisfied with that.  A little sparkly at the right angles.
 

 
With tubes: Tung Sol 5998 and Amperex Bugle Boy 12AU7.  Have the stock '72 Sylvania 6080 that shipped with the unit, as well as the stock Electro Harmonix 12AU7, plus another Amperex Voice of Music 12AU7 as well as a McIntosh by RCA 12BH7 tube, which I haven't tried yet.  
 

 
Not really satisfied with the wood finish.  Would try wood conditioner next time to smooth out the staining, and tape the edges where the glue could overflow and touch since that affects stain absorption.  Used Varithane stain (red chestnut) and glossy polyurethane finish.  It was hard to tell how much poly finish was going on with the spray - would get liquid next time and apply with brush.
 
Speedball will be added later.  No plans for other upgrades or tubes at the moment.
 
Sounds really great with DT880/600's on most tracks - some sound a little trebly/harsh (due to recording).  May pick up some HD600's to smooth out those harsher recordings.
 
Very happy so far with amp.  Haven't done a huge amount of comparative listening against my HiFiMan EF5 - both sound really good, but I do think there are some differences.  Just haven't had time to do a really good comparison yet.

 

[captouch]

Quiet here.  Haven't some of the group buy people received their kits yet?  Looking forward to hearing other people's feedback and experiences.

 

[tdogzthmn]

It's quiet because we are all too busy listening to sweet sounding music!

 

[Timbeh]

I hope they will ship my order soon, then there´s still the delivery time to Finland 

 

[Doc B.]

Hi folks,
 
We've been at the Rocky Mountain Audiofest over the weekend and we're just getting back to work today. Shipping Cracks from the recent sale is a priority and we should see lots of them going out over the next few days. Here's one Crack related comment from the show, courtesy of Tyll Hertsens:
 
http://www.innerfidelity.com/content/canjam-rmaf-2011-bottlehead

 

[kongmw]

seriously thinking of ordering my Crack. in fact the only thing holding me back right now is that i have no experience finishing wood case and aluminum plate. 
 
any suggestions on how i should go about finishing the surfaces? i've read the first 20 or so pages in this thread...

 

[Doc B.]

The chassis panel really needs no finish. The transformer end bell is raw steel and it will benefit from a spray of some kind of clear coat if you don't want to spray paint it with a color coat. As for the base, it's really easy. It just glues together with wood glue like a picture frame, using a few strips of masking tape. Just be sure to clean off any excess glue that squeezes out and let it dry. Sand it with 220 grit paper and then you can either stain it and then clear coat it when dry, or do like we do and just put on a clear urethane finish. I prefer aniline dye if it needs to be stained, but a good quality wood stain will work fine. I know some folks like the one step stain and finish products, but I have never found them to be very satisfactory. Varathane makes good clear finishes in both oil and water based versions. The oil based version will bring out more of the grain, the water based version will keep the wood grain looking more like it does when unfinished.

 

[kongmw]

Quote:

The chassis panel really needs no finish. The transformer end bell is raw steel and it will benefit from a spray of some kind of clear coat if you don't want to spray paint it with a color coat. As for the base, it's really easy. It just glues together with wood glue like a picture frame, using a few strips of masking tape. Just be sure to clean off any excess glue that squeezes out and let it dry. Sand it with 220 grit paper and then you can either stain it and then clear coat it when dry, or do like we do and just put on a clear urethane finish. I prefer aniline dye if it needs to be stained, but a good quality wood stain will work fine. I know some folks like the one step stain and finish products, but I have never found them to be very satisfactory. Varathane makes good clear finishes in both oil and water based versions. The oil based version will bring out more of the grain, the water based version will keep the wood grain looking more like it does when unfinished.

Thanks Doc! Now other than the initial sanding with 220 grit paper, is there additional sanding required between the polyurethane coats? I might just forego the staining part this time to minimize my chance of messing it up entirely. Although I'm still thinking of spray-painting the panel so it's not bare aluminum, is this (spray painting) recommended at all? Probably need to use a primer as well. Oh, and do I need to finish/seal the inside of the wooden case?

 

[Doc B.]

You can sand lightly between varnish coats and carefully wipe the dust off (tack rags are great) to get a really smooth finish. Hammertone type paint is probably the easiest finish to apply to the chassis plate, and quite durable after it hardens for a couple of weeks. I just lay on several thin coats in quick succession ( don't let them dry) to build up one heavier coat that hammers out very nicely - no primer is necessary with this paint. It will work on the transformer bell too, just be sure to clean both the plate and bell really well with a good degreaser like Formula 409 or maybe some VM&P Naptha before spraying.

 

[Armaegis]

Quote:

Thanks Doc! Now other than the initial sanding with 220 grit paper, is there additional sanding required between the polyurethane coats? I might just forego the staining part this time to minimize my chance of messing it up entirely. Although I'm still thinking of spray-painting the panel so it's not bare aluminum, is this (spray painting) recommended at all? Probably need to use a primer as well. Oh, and do I need to finish/seal the inside of the wooden case?

If you do decide to stain, I found the lighter ones easier to work with as a beginner. The dark stuff get get splotchy if you don't do it right or some of it rounds a corner if you don't notice it.
 
 
 

 

[captouch]

Quote:

Thanks Doc! Now other than the initial sanding with 220 grit paper, is there additional sanding required between the polyurethane coats? I might just forego the staining part this time to minimize my chance of messing it up entirely. Although I'm still thinking of spray-painting the panel so it's not bare aluminum, is this (spray painting) recommended at all? Probably need to use a primer as well. Oh, and do I need to finish/seal the inside of the wooden case?

As a beginner to all this, I did have some complications with the stain and finish.  The staining complications came from having some wood glue seepage near the corners that affected absorption of the stain in those areas.  If I had to do it again, I'd put blue painters tape on the exterior edges so any glue seepage would be blocked from hitting the actual wood.  And then the spray on polyeurethane I used either didn't go on thick enough or I didn't wait long enough for it to dry (though I wanted 24hrs which the instructions said was fully dry), because when I tried to sand before the final coat, I ended up sanding some of the stain off.  So if you like the natural alder color okay, it would eliminate one possible mess-up to just leave it natural color and finish it.  Even if it's not perfectly smooth, you're not dealing with a non-uniform or blotchy stain.
 
As for the bare aluminum, that was pretty easy.  I used Rustoleum Universal (primer and paint in one) Metallic spray paint.  The only non-ideal thing I did was not apply it as uniformly as I should have, but it didn't show up as bad in the end.  As they advise, more light coats is better than few heavy costs in terms of the end result. Both with the build itself (soldering) and the finishing, don't rush if you can help it.  Be patient.