Crack;Bottlehead OTL - Page 92

Quote:

Originally Posted by networkn 

I would really like to find a nice Black Finish on the wood. Anyone able to recommend something?

I used Ebony Minwax stain with 2 coats of Minwax polyurethane and mine looks great.  It's not black black (has an ever-so-slight brownish hue to it) but if you put 2 coats of the Ebony stain on it, I think you could end up with the pitch black look. 

Thanks for the compliments. The finish is simply a Jarrah timber stain on pine wood, then multiple coats of polyurethane spray rubbed down with 800 grit between about 6 coats. I've been thinking of re-making the woodwork on it as I have gotten hold of some nice western red cedar on which I'd try bees wax. But for now the Crack looks good and performs well. Just I'm keen to do the Speedball upgrade, or build another Crack with that upgrade to try to pick the sonic differences... will have to contact Bottlehead 

How much difference in sound will I hear from Crack + Speedball with my HD 650's vs my O2+ODAC combo?

Quote:

Originally Posted by scjarrett87 

How much difference in sound will I hear from Crack + Speedball with my HD 650's vs my O2+ODAC combo?

 

Apples and oranges comparison.  You are asking folks to comment on differences between a tube amp (no DAC) and a solid state amp and DAC.  I have the Crack + Speedball and can tell you it sounds excellent with Beyer T70 and other 250 ohm or higher impedance cans.  But, I am feeding it lossless files via an Emotiva XDAC-1.  Have never heard either the O2 amp or ODAC.

Quote:

Originally Posted by BmWr75 

 

Apples and oranges comparison.  You are asking folks to comment on differences between a tube amp (no DAC) and a solid state amp and DAC.  I have the Crack + Speedball and can tell you it sounds excellent with Beyer T70 and other 250 ohm or higher impedance cans.  But, I am feeding it lossless files via an Emotiva XDAC-1.  Have never heard either the O2 amp or ODAC.

Also keep in mind that even [Crack] vs [Crack + Speedball] sounds different, for the better.  Speedball is definitely worth the extra cash.

Someone also asked earlier if they could just install Speedball in conjunction with building the Crack.  You can, but it is recommended you build the Crack FULLY first and run resistance and voltage measurements to ensure everything is installed correctly.  THEN uninstall those components to be replaced with Speedball.  Some have run into issues integrating the Speedball installation into the Crack and it could take considerable more time to troubleshoot than just the Crack itself.

Quote:

Originally Posted by Mak333 

Also keep in mind that even [Crack] vs [Crack + Speedball] sounds different, for the better.  Speedball is definitely worth the extra cash.

 

Someone also asked earlier if they could just install Speedball in conjunction with building the Crack.  You can, but it is recommended you build the Crack FULLY first and run resistance and voltage measurements to ensure everything is installed correctly.  THEN uninstall those components to be replaced with Speedball.  Some have run into issues integrating the Speedball installation into the Crack and it could take considerable more time to troubleshoot than just the Crack itself.

Thanks, that is very useful. 

I will complete the crack amp first (Started last night and assembly less to the beginning of the soldering section took about 1.5 hours I think. Most of that time was spent trying to determine which screws were which etc, I think it could be clearer honestly, as for those of us who a) don't work with this stuff a lot and b) work in metric, these descriptions can be troublesome. 

Quote:

Originally Posted by irishsammy 

I used Ebony Minwax stain with 2 coats of Minwax polyurethane and mine looks great.  It's not black black (has an ever-so-slight brownish hue to it) but if you put 2 coats of the Ebony stain on it, I think you could end up with the pitch black look. 

Hmm trying to find the equivalent product in NZ is proving to be difficult as we don't have a lot of the brands people talk about here. Is there a specification based description I could use to try and track down the equivalent?

Just go to the hardware store and ask someone in the paints department about wood stains and they should be able to fill you in on what you need. Bring a piece of the enclosure with you.

Quote:

Originally Posted by skeptic 

So I had a chance to do a little monkeying around with my crack over the holidays, including the installation of a pair of 100 uF / 400 V obbligato's in place of the 91 uF axons I was previously running as output caps. The folks in the bh forums weren't kidding about the easily audible improvement you can get from changing up these caps! Treble instruments are now totally grain free, and the bass response is bigger and better than it was with the axon's - although I imagine the latter has more to do with the change in capacitance than anything else (based on Doc et al.'s comments about expected bass roll off from using lower value caps).
In any event, if any of you are looking for a <$100 upgrade with an obvious impact on sound quality, this is definitely worth considering and only takes about 10 minutes if you already have zip tie pads in place. Happy listening and new year to you all!

Could you post some pictures?  I've been thinking of "upgrading" my Crack/Speedball, but afraid to mess with it.  Sounds so good now.

Quote:

Originally Posted by lextek 

Could you post some pictures?  I've been thinking of "upgrading" my Crack/Speedball, but afraid to mess with it.  Sounds so good now.

Sure lextek.  Beefy held my hand through doing this, and hopefully these pics will give you what you need.  I haven't photographed the internals with the new obbligato's installed, but they are similar in size to the axon's depicted below (albeit a little longer).

I would recommend going about it in the following order:

First - install fly leads for the output caps before doing your speedball.  You can see that I am still using the stock caps at this point, but they are now on leads.  This is really the most important piece of the equation because it would be a real hassle to do after installing the speedball boards.

Second - based on the size of the caps you ultimately want to use, measure the placement of your zip tie mounts, then drill your top plate to install the zip tie mounts that will hold your film caps in place.  Here are photos of the top and bottom showing the mounts and visible screws on the top, prior to installing the film caps:

Third - solder in and tie down your film caps:

Fourth - sit back with drink in hand and enjoy the music.  Hope this helps!

How much for a pre-assembled unit? Does Bottlehead even offer such a service any longer?

What difference do you get when you upgrade the caps? Does it change the sound character? and is it really noticeable?

I am just starting the soldering section and I found : 

  AC Mains and power switch wiring