[bloodhawk]

So I'm getting ready to mod my Bottlehead crack and was getting my shopping list ready. I've decided on adding a choke, replacing the 2 output caps with film caps, modding the power supply with cree diodes. Anyone got suggestions on what to purchase to mount the choke? I think I've got the film cap mounting and the PCB board down.

I used the spacers from this -https://www.amazon.com/gp/product/B018C19KJ0/ref=oh_aui_detailpage_o08_s00?ie=UTF8&psc=1

Wrapped them in electrical tape for good measure.

 

[Demoninja]

Thanks for the suggestions, went with the set from Amazon. Just waiting for all the parts to come in and I can get started modding.

 

[Quadfather]

I am getting a low-level ringing in the Left Channel. When I tap on the tubes it goes away for a while. Does this sound like one of the tubes?

 

[FunyunBreath]

I am getting a low-level ringing in the Left Channel. When I tap on the tubes it goes away for a while. Does this sound like one of the tubes?

Yeah that sounds like microphonics in either the driver or power tube. If the tube is fairly new then sometimes that can go away with burn in. Try leaving the amp on for 3-4 days straight to give the tube cathodes time to form.

 

[Quadfather]

Yeah that sounds like microphonics in either the driver or power tube. If the tube is fairly new then sometimes that can go away with burn in. Try leaving the amp on for 3-4 days straight to give the tube cathodes time to form.

There have been a few times that my Crack shuts itself off, but it's rare. When I tap on the power tube the ringing will temporarily go away. Sometimes that happens with the smaller tube as well. Damn, still sounds great. I have an RCA CRC 6080 and an RCA 12AU7A

 

[bloodhawk]

There have been a few times that my Crack shuts itself off, but it's rare. When I tap on the power tube the ringing will temporarily go away. Sometimes that happens with the smaller tube as well.

That is not normal. I would check the wiring pronto. Along with the solder joints, could be a cold joint somewhere.

 

[Quadfather]

That is not normal. I would check the wiring pronto. Along with the solder joints, could be a cold joint somewhere.

What kind of solder should I use? I use tin- lead 60/40 rosin core solder to fix a loose wire but everything else looked good. And said it was for electronics.

 

[bloodhawk]

What kind of solder should I use?

Any 60/40 rosin core leaded solder is fine. I personally prefer Kester. Though people would love to sell you on Cardas / Audio grade solder etc... But that is a totally different can of worms.

Main thing with soldering though, is to use flux. Apply flux, heat up joints while feeding solder in. With the properly heated joints, the solder will easily flow across.

 

[attmci]

What kind of solder should I use? I use tin- lead 60/40 rosin core solder to fix a loose wire but everything else looked good. And said it was for electronics.

All of the joints.

Those two tubes can be obtained for $10 each, so no big deal.

 

[Paladin79]

Most solder is hollow core and already contains rosin flux. On occasion extra flux is needed to clean new metal.

 

[Quadfather]

@bloodhawk, is it normal for one side of the tube to be so much brighter than the other?

 

[bloodhawk]

@bloodhawk, is it normal for one side of the tube to be so much brighter than the other?

Not really.
But unless your voltages are off , or you are having channel imbalance , i think you should be ok.

 

[Quadfather]

Not really.
But unless your voltages are off , or you are having channel imbalance , i think you should be ok.

The channel balance is fine, and the amp sounds drop dead gorgeous. I am thinking maybe the tube imbalance in brightness is a sign that it's going bad which may be part of the problem

 

[bloodhawk]

The channel balance is fine, and the amp sounds drop dead gorgeous. I am thinking maybe the tube imbalance in brightness is a sign that it's going bad which may be part of the problem

Definitely could be, some tubes start becoming micro-phonic as they are about to go bad.

 

[hawkwindx]

What song or songs makes your Crack shine?

It’s a question that’s been asked a lot, but it’s nice to discover something new. Something I recently discovered is “Sinatra At The Sands”.