[mcandmar]

Funny when i seen that pic of the open side i was going to post and say for god sake be careful around that amp.  Then decided not to state the obvious...

 

[olegausany]

Hi there
 
I have a NOS NIB Tung Sol black glass black plate 12AU7 I'm selling (ordered six weeks ago, but just arrived) - Please see my signature for link to listing (sorry Lachlan - I need to sell). 
 
Also the following:
Matched pair NOS NIB 6AS7G RCA JAN
NOS NIB Tung Sol clear top 12AU7A
Tung Sol clear top 12AU7 (used but strong, printed marking rubbed off)
3 x used but strong Tungsram E80CC (white box)
Quite a few Baldwin branded but Japanese made 12AU7 tubes (white box, lightly used but strong)
Matched pair Mullard ECC82 (Mitcham 1960) wrinkled glass (white box, lightly used but strong)
RCA 5963 (driver tube for Crack) long black laddered plate with top D getter, 1956 (NOS, white box)
 
That's it gents and I'm out of tubes for the Crack.
 
Let me know if you are interested in any or all of the above.  I am in the middle of a major depressive episode, agoraphobic, unable to work and out of money, so you would be doing me a favour.
 
Cheers and sorry for the sob story.
 
Nathan
 

 

By any chance any of the 12AUs sound exactly as Mullard E80CC?
Why am I asking cause I just got Simens 12AU which does exactly that

 

[captslow]

Just read through this thread... The Crack just made it to the top of my want list. It is unbelievably cheap and looks like a fun project, may have to build it and the reduction for my turntable. 

 

[Bimbleton]

Painting & varnishing the wood to make it look nice... does that have to be done before or after assembly?

 

[Loquah]

  Painting & varnishing the wood to make it look nice... does that have to be done before or after assembly?

 
It's probably easier after assembly because gluing will be tricky once there's varnish in the joints.
 
I've done the stain and varnish on both of mine after assembly with no problems.

 

[drizek]

   
I'm glad you didn't die too!!
 
Very important to take lots of care when testing the circuit and always unplug the cable from the power socket (i.e. mains power supply) before doing anything "under the hood". A friend of mine fried himself on a capacitor even after unplugging the unit for a few minutes (the circuit was faulty and didn't drain the caps) so beware of loaded capacitors to - a rubber handled set of pliers can serve as a good guinea pig for live current.

 
It was a bit ambiguous in the manual, so I figure I will ask: the capacitors in the Crack will be drained automatically by resistors after a few minutes, right? I'm not an electrical engineer or anything so I don't understand the diagrams intuitively, but my goal is to actually know what all the bits and pieces do before I go ahead and upgrade it with a speedball and make it even more complex.
 
Anyway, I couldn't stand not being able to listen to it due to my lack of possession of RCA cables, so I unplugged my subwoofer and used that cable to get one channel connected. At first I was concerned that the volume was really low, then I realized that I had plugged it in to the other channel, and all the volume I was getting was actually crosstalk 

. How much of that is normal for this amp? At maximum volume, the crosstalk alone reaches a comfortable listening level.
 
Edit: I do enjoy taking pictures of this thing, 
 

 

[Loquah]

   
It was a bit ambiguous in the manual, so I figure I will ask: the capacitors in the Crack will be drained automatically by resistors after a few minutes, right? I'm not an electrical engineer or anything so I don't understand the diagrams intuitively, but my goal is to actually know what all the bits and pieces do before I go ahead and upgrade it with a speedball and make it even more complex.
 
Anyway, I couldn't stand not being able to listen to it due to my lack of possession of RCA cables, so I unplugged my subwoofer and used that cable to get one channel connected. At first I was concerned that the volume was really low, then I realized that I had plugged it in to the other channel, and all the volume I was getting was actually crosstalk 

. How much of that is normal for this amp? At maximum volume, the crosstalk alone reaches a comfortable listening level.

 
Yes, the resistors will drain the capacitors fairly quickly once power is disconnected.
 
I don't fully understand your setup with the woofer cable, but there is very little crosstalk (i.e. not noticeable even with excellent cans) in the normal setup.

 

[drizek]

   
Yes, the resistors will drain the capacitors fairly quickly once power is disconnected.
 
I don't fully understand your setup with the woofer cable, but there is very little crosstalk (i.e. not noticeable even with excellent cans) in the normal setup.

It is just a single RCA cable, so I only get one channel. I initially had it hooked up to the wrong channel, so the sound coming into my headphones on the right channel was actually all from crosstalk from the left channel. 
 
I guess I'll have to go through and see where this might be coming from. 

 

[sjeffrey]

   
Yes, the resistors will drain the capacitors fairly quickly once power is disconnected.
 
I don't fully understand your setup with the woofer cable, but there is very little crosstalk (i.e. not noticeable even with excellent cans) in the normal setup.

 
This confuses me too.  I understand that you took just 1 cable so you have either a left or a right plugged in.
The only thing I can think of is either your cable was carrying the crosstalk and not the crack generating it(?)
Or, you have something wrong with your wiring and 1 channel is not working and cranking volume up allowed you to hear the music in other channel.  Have you tried plugging the one cable in each channel?
 
EDIT: Have any component cables around?  That would work just as good as your subwoofer cable

 

[drizek]

The other complication is that my HD 580 cable's left channel is gone, so I am waiting on a new pair of Sennheiser cables before I can actually listen in stereo. My actual setup was Left Out of DAC, Left In to Crack (with the woofer cable), then the headphones plugged in, but with only the Right side functioning. So the sound I was hearing through the Right driver was actually going into the Crack through the Left channel. 
 
And I couldn't find any component cables either. I made a point of making my home theater system 100% HDMI 1.4.

 

[sjeffrey]

  The other complication is that my HD 580 cable's left channel is gone, so I am waiting on a new pair of Sennheiser cables before I can actually listen in stereo. My actual setup was Left Out of DAC, Left In to Crack (with the woofer cable), then the headphones plugged in, but with only the Right side functioning. So the sound I was hearing through the Right driver was actually going into the Crack through the Left channel. 
 
And I couldn't find any component cables either. I made a point of making my home theater system 100% HDMI 1.4.

LOL, this has got to be the sketchiest setup so far.  And you are telling us you got shocked?  No!, really??

Just messing with you.  I'm sure you'll enjoy the crack once you get RCAs and working headphone cables

 

[Loquah]

  The other complication is that my HD 580 cable's left channel is gone, so I am waiting on a new pair of Sennheiser cables before I can actually listen in stereo. My actual setup was Left Out of DAC, Left In to Crack (with the woofer cable), then the headphones plugged in, but with only the Right side functioning. So the sound I was hearing through the Right driver was actually going into the Crack through the Left channel. 
 
And I couldn't find any component cables either. I made a point of making my home theater system 100% HDMI 1.4.

 
Not sure what would have caused the cross-talk, but I just checked my Crack with my Beyer T1s and there was no audible cross-talk and listening levels. I couldn't turn a channel up to full volume without risking damage to my cans.

 

[amcananey]

LOL, this has got to be the sketchiest setup so far.  And you are telling us you got shocked?  No!, really?? :blink:
Just messing with you.  I'm sure you'll enjoy the crack once you get RCAs and working headphone cables

Word. That is seriously the funniest, most effed-up way to test the Crack I've ever heard of. Next thing I know you'll tell us your source only outputs a signal on the right channel...except when there is a Tuesday with a full moon, in which case it is reversed...


Adam

 

[palmfish]

Oh, come on...ease up a bit everyone.

You remember how excited you were to power it up and listen after the build was done. He's only doing what each of us would do given the same circumstances - which admittedly, are pretty hilarious...

I must say drizek, you do take really good photos!

 

[drizek]

I couldn't help myself. It was sitting right next to me all day, glowing, begging to be listened to.