50 Hz Humm...

[Guy 13]

I can see the third power supply cap in the first of the two "pictures before shipping" (horizontal at the back on the left).  So Geary installed it. 

However you might have received it in a plastic bag if it somehow fell off before delivery. 

A photoflash cap should help you troubleshoot this problem.  Try some jumpers and attach the cap with the negative lead on terminal 12 and the positive lead on terminal 13.  Both of them go in the upper openings of the terminals when you get to soldering.

I can't remember about photoflash caps.  I think they dump energy quickly, which is a good thing.  So for testing they should be fine.  Probably good permanently.  Although this is the spot you can put in a film cap for an upgrade so keep it in mind.

Hi Grainger49
After a nation wide investigation involving my wife and myself,
we have discovered that the capacitor has fell off from the circuit
and was put into a Ziploc bag,
of course the guilty person would not admit her guilt...
I have to take also part of the blame for misplacing the Ziploc bag
with the precious little capacitor inside.
The instruction manual as vanish from the surface of planet Vietnam
and we have not found yet someone to blame
Your jumper idea is a great idea,
I don`t know why I did not think of that myself,
well I guess I am not as smart as you are.
Minds you, I can live with that, since I have access at this forum filled to the rim with smart people.
Photography flashes do dump their load of electron very fast
and if that`s good for audio, that`s good for me also.
Now it`s too late to start any project involving electrocution potential, so, it will have to wait until tomorrow when I will be fresh, alert and rested.
Get back to you tomorrow if my wife don`t request my assistance for something involving manual work.

Guy 13
 

[Guy 13]

Hi Grainger49 and all.
They say only the crazy don't change their mind,
well I guess I am not crazy or if I am, I am just a little.
I could not wait and resist trying the capacitor with jumpers.
So, I did it and guess what ?
No more humm, the humm is gone, the humm is a thing of the past,
the humm is dead and the Crack is dead silent.
Yes, the Crack work like it's supposed to.
I've listen to a few CD tracks and to my ears, it sounds good.
I will go with the permanent soldering of the 220uF - 400V [M] brand capacitor.
So, the adventure is finish, it's over, it's athing of the past.
At last, at long, long last I can enjoy my Crack/HD-650 combo,
minds you, I still find the sound DARK...

Guy 13

[Grainger49]

Guy,

The guys at Bottlehead are pretty good at designing quiet power supplies.  Without the last cap in there there was still a little ripple in there that would have disappeared on the final bit of filtering. 

A good "Fast" cap there is a good thing.  This is why so many people only upgrade the last stage of the power supply, it is the one that feeds the circuit.

[Guy 13]

Hi all.
My sick Bottlehead Crack that needed to have a capacitor transplant came back from the emergency room and he’s now in my reanimation room or if you prefer; in my listening room.
As per the pictures below, you will see that the Vietnamese doctor did a decent job and most important, he did not charge me exorbitant amount of $$$ as many other doctor would do for such a small operation.
Soon, I will check the blood pressure or all the resistors values and then check the hart beat or all the voltages throughout the operated body of my Bottlehead Crack.
I will write up a printable and complete report as soon as possible.
See you later alligators…

Guy 13
Life without humor is not life, its hell.

[Guy 13]

Hi all.
I did full examination of my Crack vital organs
and everything check good, it will outlive me that's for sure.
However, I still don't like the shaved off harmonics of the HD-650
I wonder what other brands and models would be better.
Maybe the Bayer Dynamics DT-990 300 Ohms ? ? ?

Guy 13