50 Hz Humm...

[Guy 13]

Hi all.
I have a steady 50 Hz humm that is always present
and disturb my listening enjoyment.
I cannot hear it when the music is playing,
but between track I can clearly hear it.
I have checked the ground connection, the interconnects in case they pick-up line voltage.
I have changed the tubes, even if I don't think that could be the problem.
The level of humm as a fix level and is not affected by the position of the volume control.
I am posting some pictures in case you can see something suspicious.
What and where should I look for.
Other than that, my Crack is breaking in slowly, but surely,
I am getting closer to the magical 100 hours.

Guy 13

I don't remember if the problem was there on day one ?

 

[Paul Birkeland]

Hello Guy,

Are your electrical outlets grounded?

Does this happen with all your sources? (try playing music from a laptop running off its battery if possible)

PB

 

[Guy 13]

Hello Guy,

Are your electrical outlets grounded?

Does this happen with all your sources? (try playing music from a laptop running off its battery if possible)

PB

Hi CB or PB.
Yesterday, I tried the Crack with my Rega Apollo CD player
(Both of them on a certified by me grounded outlet.)
and I had the same humm.
Today, I will try with my laptop running on battery
and get back to you with my findings.
Thanks.

Guy 13

 

[mcandmar]

Shouldn't there be three caps in the power supply?

 

[Doc B]

Yup, Mark called it. You forgot one power supply cap.

 

[galyons]

That's a bit weird!  Here are the final pics before shipping....

Was there a cap loose in the box?  Dazed and Confused,

Geary

 

[Guy 13]

Hi all.
Yes, now that I think of it, there was a capacitor in a Ziplock type bag.
My problem now is...
I don't know where I've put it ? ? ?
I just finish looking for it, but no luck.
What is the value (uF) of that capacitor?
I have many capacitors that I use for my photographic flashes,
but they are all 360WVDC.
Also, can you give me directions where to install that capacitor?
Maybe a picture would be best,
because a picture is worth a thousand words.
Waiting for your help so I can fully enjoy a cemetary type of silence
from my Crack.

Guy 13

 

[Doc B]

Am I getting it correct that Geary built this? If so I will request that the community respectfully let him help you get it up and running. After all if a person takes on the job they should be allowed to follow it through to completion.

 

[galyons]

Am I getting it correct that Geary built this? If so I will request that the community respectfully let him help you get it up and running. After all if a person takes on the job they should be allowed to follow it through to completion.

Yes, I built it after visiting Guy in Vietnam, when  our family traveled there.  Absolutely agree that it is  on me to get this resolved with Guy. All three caps were installed and tested before shipping.  There is a another thread discussing the project.

Given the transit challenges from here to Vietnam, no telling why the cap is not there now. Honestly I am thrilled that it played out of the box after the trip!  But, fortunately, this is one of the easiest caps to solder back in, and should, indeed, resolve the hum issue.

Cheers,
Geary

 

[Mach2]

Hi Guy 13,

I checked my manual. Looks like the missing cap is of the same type of the other two sitting nearby, so it should be a 220uF 250V one.
Are you living in Saigon? You should be able to find a replacement easily in a local electronic shop.

Let me know if you need my help.

PH

 

[Guy 13]

Am I getting it correct that Geary built this? If so I will request that the community respectfully let him help you get it up and running. After all if a person takes on the job they should be allowed to follow it through to completion.

Yes, I built it after visiting Guy in Vietnam, when  our family traveled there.  Absolutely agree that it is  on me to get this resolved with Guy. All three caps were installed and tested before shipping.  There is a another thread discussing the project.

Given the transit challenges from here to Vietnam, no telling why the cap is not there now. Honestly I am thrilled that it played out of the box after the trip!  But, fortunately, this is one of the easiest caps to solder back in, and should, indeed, resolve the hum issue.

Cheers,
Geary

Hi Geary.
I wonder if the capacitor that I saw in the Ziplock bag was put in there by my wife's aunt,
because she brought the Crack in a large hand bag that was inside her luggage.
I might have unsoldered and fell and she picked it up and put it in a zip bag.
I will look again for it, I've have missed place it, if not, I will not loose my time and buy you, mind you, if I could use my  220uF /360V Hitachi capacitor if would be great because I've got hundreds of those in my warehouse and they are not much bigger than the original.
Please let me know what you think.

Guy 13

 

[Guy 13]

Hi Guy 13,

I checked my manual. Looks like the missing cap is of the same type of the other two sitting nearby, so it should be a 220uF 250V one.
Are you living in Saigon? You should be able to find a replacement easily in a local electronic shop.

Let me know if you need my help.

PH

Hi PH.
As I mentioned in my previous post, I have lots of 220uF/360V Hitachi capacitor that I could use.
Now, where does it go ?
Can you post a copy of the page where they show where it goes
or should I ask Geary?

Guy 13

 

[galyons]

Can you post a copy of the page where they show where it goes
or should I ask Geary?

Guy 13

Guy,
Please see email sent about an hour ago.

Geary

 

[Guy 13]

Hi all.
I am now in contact with Geary who put together my Crack and he did a very fine job.
It's a fact that one capacitor is missing, but Geary is in no way responsible for that,
it's my wife's aunt that took the Crack from a very well packed FedEx box that Geary put together
and put it (Believe me or not) in a hand bag within a box of clothing as shock absorbent material.
She probably broke off the capacitor when she transfer the Crack from the box to the hand bag
and to a new box.
I am sure she did not do it on purpose, but by ignorance and lack of experience.
I found a capacitor and on Monday it will be soldered by a young man without shaking hands like mine.
I will get back to you on Monday, because Vietnam is now on a 5 days National Holiday.
My God those Vietnamese have so many holidays they don't know how to call them.
The proof of that: They have an holiday called: The insects holidays.
Believe me or not...

Guy 13

 

[Grainger49]

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.

 

[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