Every hobby has it’s staples and with audio I would say you would be hard pressed to find a piece more well regarded than the Bottlehead Crack. Accessible, customizable, modable, well priced and well supported on by the BH and multiple forums. It is a great first step into the OTL tube world.
I bought a kit last year and kind of forgot about it but the talks on the forum have me trying to set aside time to even just start assembly. First steps first. I have everything finished and the soldering iron ready to go. Currently looking at helping hands for soldering, I will take suggestions on types that work well. @MazeFrame I am sure you may have an opinion here.
The chassis is lacquered and the plates and powdered, both gloss black. The lacquer was done by good friend Cris Mirabella ( Mirabella Guitars ) who does amazing guitar work. His work has been in NYC’s MET Museum of Art, he has done reproduction work for Gibson, and his finishes are . The stripe around the top is a faux binding. Instead of cutting a notch and inlaying something, the black lacquer is scrapped back so you see the wood underneath. I am trying to find some gold lettering I can put on as labels but I have had no luck yet.
Depends on what type of work you do. Those PCB-clamp holders are nice for inspecting and fixing PCBs (who would have guessed ). Likely not super helpful with the BHC.
As far as the mods are concerned, pick and choose since what you do to yours is what makes it yours!
I spent time reading through this guide before I upgraded mine, useful stuff and it’s nice to see the “upgrades” by order of meaningful impact and the fact that it mentioned the nice to haves but not necessary.
So now you have assembled your stock Bottlehead Crack OTL amplifier, it’s time to learn how to upgrade it to the next level!
There’s a couple of fun quotes from the man himself which made me laugh. Certainly someone that understands the mindset. lol
“No need for $350 teflon caps or $200 stepped attenuators. My suggestion is to try Audyn 100uF 400v cap from Parts Express and an Alps blue velvet pot. They deliver good bang for the buck.”
“… to further develop the thought, it’s not just that there is a new flavor of cap every week. It’s that so many people want to represent themselves as polishing a turd by putting a $300 cap in a $300 product.”
The crack is basically the only sub 1k amp I keep around, sure it doesn’t match up to what else I have on hand, but it’s unique enough and enjoyable enough for true casual listening it can justify it’s existence even with a far amount of other options laying around, which is at least high praise from me lol. Excellent for those times when you just want to kick back and relax with some senns or beyers and not pay attention to the music, just be enveloped by it
Mods: wired internally with Kimber, mundorf msolder silvergold, mundorf Evo oil output caps, audio note potentiometer, lundahl choke, and another mundorf foil cap in the psu. Perhaps something else that I’m forgetting. Generally all this did an excellent job at improving dynamics, resolution, background, and staging while still maintaining the cracks warmer fun nature but tightening up and refining it a bit (not too much though)
Tubes: Mullard GB CV4003 & CV2984, this really has given me the signature I want, that rich, warm, organic, and smooth tone but still having reasonable technical ability, very enjoyable combo
Yes, im thinking of grabbing the alps and the Jensen Capacitors. TBH I used jensen in guitar work and theyre probably in my guitar now but the values will be way different. They were always suggested as they were “vintage correct” paper in oil. Right now though im having one heck of a time finding any Jensens even listed anywhere.
This is basically what I want. Ive been saving the HD6XX just for when i get this kit and finish it. Then hoping the next Sunday morning I am off work and it’s a relaxing autumn rainy day outside and that cup of black tea hits the sweet spot.
In case anybody wants a Bottlehead Crack but isn’t comfortable building it themselves, I can highly recommend James (etsy shop TheHeadAmpBuilder). He is a bit expensive, but the quality of his work is unmatched.
Noted, maybe I go audio note then. The tkd is about 1/3 the cost of what I payed for the kit and I think will be overkill for me.
Yes, it seems there are a lot of jensen out there that all look the same. I also looked at that site before and I didnt realise that you had to dive through a few layers then hit “buy now” on the bottom. It came across more as a info site.
I was also tempted to send my kit to him/buy a kit that was built by him and swap it into my chassis then sell my kit. Very good clean work and I heard he provides good support as well.
I’m almost sure most people know they aren’t really getting their money back when they go nuts with crack mods, it’s more a pet project and just for fun for them. There’s not really an amp that can replace it, so why not have fun taking it to the limits
Personally, I would save the huge cap money and invest in tubes if I wanted to really go for changes but to each their own. And why not both?
I would also think once you sink huge money into the bhc, I would think in investing into a decware, but tbh I have not heard a dec to say its anything besides sharing some inspiration.
That’s personally exactly what I would do if I wanted that sort of signature. I just modded my crack for fun knowing that it wouldn’t bring returns
If I had to say the most valuable mods to the crack, it’s obs the speedball (almost necessary imo), upgrading the volume pot (as you can get a better one for not much more), and then getting better output caps (try for foil caps). Not including tubes. Depending on your power situation if you can source a cheaper choke like a triad 10h that can make a big difference depending on your situation
. The stripe around the top is a faux binding. Instead of cutting a notch and inlaying something, the black lacquer is scrapped back so you see the wood underneath. I am trying to find some gold lettering I can put on as labels but I have had no luck yet.
). Likely not super helpful with the BHC.
