Great,
Hate to see you have to spend mega-bucks on tubes but in the past few years since I had my Crack and several other tube amps the prices have just gone bonkers…
Do you have ebay sellers in Aussie land?
Alex
Not aware of any.
6080 Tube search on ebay.com.au has something like 14 actual tube hits. Lot expensive
This maybe: https://www.ebay.com.au/itm/6080-Electronic-Tube/223640245049?hash=item3411ff5339:g:BHEAAOSwybZdZaRa
They would do just fine.
As long as the seller is honest and they are really NIB, thats a good find…
BEST OFFER!! So try that for $30?
Alex
Yeah, low feedback always worries me, probably shouldn’t.
I have a friend lending me his VC, he well into Tubes, may have something I can borrow for a short run.
Side note: Its next to me, say a foot n half away, and it hit 30c today, and its warm. Tubes + Queensland weather, ugh. Need the air con on just to feel like a normal temp.
With amps with no feedback the impedance can be an issue, but when its done well the results are stunning…my TUBA is a great example of this…no feedback and really a clearm wide open honest presentation…if the tube is running in its linear operating area its wonderful…
Alex
A friend has lent me;
Sylvania 7236
6AS7G RCA NOS Gray Plates 1970’s
Svetlana Winged C
Which is the pick of the bunch there to try first?
Oh, and his Verite Closed.
Just to echo what was said already…
I’ve rolled about 6 different power tubes through my Crack, and the sonic differences between many of them were smaller than the differences I hear between many DACs, if that gives you any idea about it. Find a solid yet inexpensive 6080 and be done with it is my advice.
The 12au7 input tube is where the sound changes the most, and that’s where I’d be putting my money. In my experience:
Most Amprex are usually amazingly clear and detailed,
Mullards are like a mug of hot coco and a blanket on a cold snowy day,
Sylvania/RCA seem fairly balanced and kinda sexy in some areas, but I wouldn’t introduce them to my parents,
GE should be avoided like the Corona virus.
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Yeah fair.
I have a stock input tube and a Brimar CV4003
And in the power I have a few to choose from at the moment as said above.
Will test some tonight. Winged C looks the coolest 
The 7236 probably be the pick for cleanness
The Tall Coke Bottle RCA 6AS7G’s I have a bunch of them, they are my favorite.
I have Bugle 12AU7’s they are nice but so are a bunch of JAN 5963’s I have USN mil spec stuff…
In the pix is a very stable RCA with a RCA Clear top 12AU7A…my favorite for a long time…but again
there are other tubes that will make you smile as well…
Its all in you "Head!!..
:>)
Alex
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FYI…After selling a ton of stuff this am I turned on the Crack to see if I would sell it.
Listening this am and when Eric Clapton & Wynton Marsalis, Play the Blues came on with the tune “Just a Closer Walk with Thee”…
The opening etc…
BIG SMILE. HD 600’s
So the answer of me selling the Crack is:
NO!!
lol!!
Alex
“amps come and amps go…this puppy stays!”…
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So I decided to take the plunge and order a Crack kit. What’s not in the manual that I absolutely should know before building this? Also, is Crack addictive? Will I be able to see my son again?
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Yes
and No…give him a hug and kiss now while you can!
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Go to the Bottlehead site, and forum for the Crack.
Several things to read:
1st the FAQ: Crack FAQ
Then this little advice:
Since I bought my kit a few years back things have changed abit, but not much…but still small changes for the better. You should have all these incorporated in the latest manual and parts.
Get the Speedball upgrade, but dont intstall it without getting the base kit up and running well. Listen for a few weeks to get any idea of what the base sounds like, bass etc…then you will have a good idea what Speedball adds etc…
The third item in the FAQ is one that most Crack addicts install…it makes volume so yu have to turn up the vol pot more to get more travel and get out of the lower imbalance part of the pot…when you get a chance its a good upgrade to install a nice authentic ALPS pot. The original is fine, but its a low cost part and to keep the kit price down etc…many install the ALPS or even a stepped attenuator…IMO not necessary but the ALPS makes for a buttery smooth vol adjustment and the ch imbalance which I did experience always bugged me…but again build the stock Crack before you do this…then many of us can help u with the pot mod if u want to go there.
There are many mods, but most dont really improve things much more than the basic kit (not counting speedball)…but its an experimenters dream…
Doc at BH came up with the Crack-a-two-a which is really the way to go if your a modder, the basic crack circuits been around for ages and works very well as is…except for the pot upgrade all others are ok, but sonically well …your wallet will get low…better to get a Crack-a-two-a…
But that said a Crack w speed is just plaine sublime!
Tubes is the big thing for folks and lots of options but again its really a rabbit hole…
You wont know what tubes you will get until you get the kit!
I got a tall RCA 6AS7G coke bottle and a RCA 12AU7A…and still after spending $$$$ I like this combination very well…listening with it right now.
One last thing, take your time, read, and re-read the instructions, measure twice before cutting wire lengths, I hope you know how to solder well…this is the number one issue with most kits…cold solder joints, shorting out parts etc…the kit uses solid wire not stranded to avoid shorts…
Any questions or issues the forum at the BH site is wonderful and Doc and Paul Birkland will assist and answer your questions!
Good Luck!
Alex
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Thanks Alex! I can tell you really love this amp. I’m not shy to solder, since I’ve built a bunch of custom mechanical keyboards before.
I now have plenty of time over the next 6 weeks to read up on all the things you’ve sent (while I wait for the kit to ship). It’s great to see how involved and passionate everyone is on the BH forum.
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What are the typical assembling times for:
a) experienced hands?
b) never soldered anything in life?
Thanks!
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I think if you just sat down and did it with 0 experience a couple of days…with experience a couple of hours
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Well if you want it to look good, neat and nice probably 6-8 hours…less if your not Mr Neat…but if u go slow and double check stuff…your chances of things just working first time are very good…if you rush and put a wrong part in the wrong place or a diode in backwards or short one of the diodes in the power supply or on the small tube sockets…well your experience will be less than stellar…
Depending on how much of a novice you are it could be a few days…
The wood base of alder has to be assembled, glued together as well…but you can build the amp without this, get it glued up, taped and drying and you use this as a support for assembly…
If you have never soldered I would buy some cheap resistors etc on ebay or amazon etc and get some terminal strips and practice to get the heat, flux and procedure down to know what a good solder joint looks like…there are tons of videos on how to solder…its a good start…once the soldering is down its more of a mount stuff, measure wire, attach a resistor or wire around a log on a terminal strip with a good mechanical crimp, apply some flux and solder. Rinse and repeat…
Make sure you have a voltmeter and ohmmeter to do the resistance checks and it helps on knowing how to read resistance correctly. I always use a ohmmeter to measure resistors before installing…easy to mix up…
Not trying to scare anyone, its just instilling patience and doing a good job first…goes a long way.
Alex
Also get a soldering iron that will get hot enough to do the job, some solder 60/40 and flux.
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Orrrrrr… You could spend even more money and get into DIY mechanical keyboards. 
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Here is my quick and dirty prep guide for building a Crack:
It will take everyone a few days. Before you get to soldering there are several things you need to do first.
You’ll need to assemble the wood base first, as it serves as an assembly stand for everything else. I recommend making sure you have some Titebond II wood glue and some 1" wide painters tape handy. You can (and should) only worry about finishing the base after you’ve used it to assemble the amp section.
You will want to paint the aluminium base and transformer cap before you assemble the amp.
The glue for the base will take a full day to cure, and the paint at least 12 hours. That’s 1 day down.
With zero soldering experience, add another few days to that. For the inexperienced, most of your time will be taken up by checking the directions, double checking , rechecking and basically becoming paranoid about following the instructions step by step. If you follow the instructions, it’s actually pretty hard to mess this up.
If you have zero soldering experience, educate yourself before your Crack kit arrives. The cheap $20 soldering irons are hell to use, and I suggest making a basic investment for a good soldering station and tools needed to strip and trim the parts.
- Soldering station and iron tips
- Trim cutter
- Wire stripper
-
Helping hands
(The last item is optional, but very… handy.)
Since there are several times that you will be soldering many different items into the same small connection, having a variety of tips and using the right one is very helpful.
You’ll really want to know what a cold solder joint is and how to avoid it. Basically, if you are connecting several items to the same connection point, you need to ensure adequate heat is applied to everything when you apply the solder or you’ll get a cold joint. I would suggest practicing on before building the kit.
And, of course you will need to test the amp with a multimeter to make sure everything is working correctly. Fluke makes great MMs, and either of these will do nicely.
or
An edit about soldering:
Soldering is not like a glue. You don’t just apply a dab, and expect it to work. The solder will not adhere and conduct properly unless the metal pieces it is joining are hot. Really hot. In practice, it is best if you do not melt the solder with the iron tip itself. Heat the pieces of metal to be joined, and let those pieces melt the solder. If they are hot enough to melt solder, they are hot enough to correctly bond with the solder.
Pre-tin your iron tip and wires. Solder will stick to solder very quickly and efficiently. If you apply a super small amount to the leads and wires before you solder them together, you will (almost) always ensure a good joint. YouTube has more videos than you can shake a stick at for how to pre-tin wire. The videos on how to solder widely vary in usefulness, the vast majority of them don’t properly explain what causes cold joints or how to avoid them, so grain of salt with those.
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This is the correct answer 
lol…
This is the way…
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