Crack;Bottlehead OTL
Jan 1, 2012 at 11:39 AM Post #976 of 12,335
For most circuits using the 6080, you can use any of the following: 6AS7, 6AS7G, 6AS7GA, 5998, 5998, 7236, 2399, 6N13, 6N13P, and 6520.  Of course, check with the owner's manual or manufacturer first before dropping these tubes in.  Of these, I'd say the most "colorless" would be the Sylvania 7236.  On the opposite side, the RCA 6AS7G is very colored and warm.
 
Quote:
@lextek, I don't see an issue coming from this, just make sure the connections stay the same.
Also, I was going to ask this on the Bottlehead forums but havent finished registration. I have a 6080 power tube in right now, is it easily replaceable with a 6SN7? I've read a couple things about needing to rewire, but others saying its a drop and go. If anyone can help, that would be awesome =)



 
 
Jan 3, 2012 at 8:40 PM Post #978 of 12,335
Ordered the basic Crack and a couple of cheap tubes, a Tong Sol 12ua7 and a RCA 6as7g Black Plate just to get a feel of the sound, I've only heard a GE and a Raytheon lately (last 35 years or so!) and their 5670's, but don't each company have a house sound so to speak?
 
I guess I have a month or so of waiting so at least I can read up on everything Bottlehead Crack.
 
I have two receivers, a Pioneer and a new Yamaha. My DT990's sound great through both of them and I have been hesitant in buying the Crack, thinking it can't sound 2 to 300 dollars better, so why waste my money, but I had to see if I was missing anything so I pulled the trigger.  I sure hope it's better than the receivers.
 
Jan 3, 2012 at 8:44 PM Post #979 of 12,335
I run my Dt990s through my Yamaha RX-V467 from time to time.  It sounds pretty darn good.  But, they reach their full potential on my tube amp.  You're gonna love your new tubes.
 
Quote:
 
I have two receivers, a Pioneer and a new Yamaha. My DT990's sound great through both of them and I have been hesitant in buying the Crack, thinking it can't sound 2 to 300 dollars better, so why waste my money, but I had to see if I was missing anything so I pulled the trigger.  I sure hope it's better than the receivers.



 
 
 
Jan 4, 2012 at 12:09 AM Post #980 of 12,335


Quote:
I run my Dt990s through my Yamaha RX-V467 from time to time.  It sounds pretty darn good.  But, they reach their full potential on my tube amp.  You're gonna love your new tubes.
 


 
 



Second this. I haven't run them thru a receiver, but the sound upgrade from my NFB-12's amp is a lot higher than I could have imagined.
 
Jan 7, 2012 at 5:12 PM Post #982 of 12,335
Ah you're killing me.  I ordered mine on 12/6.   Still waiting.  Have to get by with a non-tube sounding Valhalla.......
Wish I had my old MG Head
 
Jan 7, 2012 at 5:27 PM Post #983 of 12,335
All I can say is put your stain/coat on your finished base BEFORE you finish the circuit! I'm doing mine after (waiting for a poly coat to dry right now), and it sucks having to not listen to it!
 
I almost dropped for the Valhalla, but I couldn't resist Crack, and now I'm hooked!
 
Jan 7, 2012 at 5:36 PM Post #984 of 12,335
When I get my Crack.  I'm planning on relocating the headphone jack to the front plate and the RCAs and IEC to the rear.  I've had time to think about it.
 
Jan 7, 2012 at 10:20 PM Post #987 of 12,335
Thank you :)
 
 
I also thought about putting my jacks like that lextek, it makes more sense, but for some reason I've grown fond of everything coming out of the top.
 
 
Also found out today that the humming noise wasn't coming from my tubes, but actually my RCA jacks. When they are unplugged, completely silent. But when I plug the jacks in, even if the DAC isn't turned on, I get that static-y noise.
 
Would my jacks not be properly grounded, or perhaps a crappy solder into the jacks?
 
Jan 7, 2012 at 10:23 PM Post #988 of 12,335
Could be a ground loop.  Try running your DAC on a different circuit than the amp.  A different outlet on the same circuit would still cause a hum.  If you discover running the power from a different circuit fixes the problem, then it's a done deal.  If running the cords is a pain, you can get a $17 ground loop isolator from Radio Shack.
 
Quote:
Also found out today that the humming noise wasn't coming from my tubes, but actually my RCA jacks. When they are unplugged, completely silent. But when I plug the jacks in, even if the DAC isn't turned on, I get that static-y noise.
 
Would my jacks not be properly grounded, or perhaps a crappy solder into the jacks?



 
 
Jan 7, 2012 at 11:11 PM Post #989 of 12,335


Quote:
Could be a ground loop.  Try running your DAC on a different circuit than the amp.  A different outlet on the same circuit would still cause a hum.  If you discover running the power from a different circuit fixes the problem, then it's a done deal.  If running the cords is a pain, you can get a $17 ground loop isolator from Radio Shack.
 


 


Thanks for the help! Tried it, didn't work. Just to see, I plugged my crappy turntable's RCA jacks into the amp, dead silent. Then I plugged the RCA plugs from my DAC in, but unconnected. Still no noise. But connecting them, noise. I'm going to find some other RCA plugs to see if my cables are the problem, if not, then I'm going to try resoldering.
 
 
Jan 10, 2012 at 11:41 PM Post #990 of 12,335
This is a question for those that painted the power transformer on their Crack. Did you use special paint or apply any primer? The reason I ask is I have some Rust-Oleum primer and flat black lying around. The directions say not to use on surfaces that exceed 200 degrees Fahrenheit or on galvanized metal. I'm not sure if the Crack's power transformer gets that hot. I'm assuming no, but wanted to ask before starting the paint process.
 

Users who are viewing this thread

Back
Top