weird noises - malfunction Einstein, watch vid!!!

[Sebwo]

Hi,
does anyone know what the problem is?

https://www.youtube.com/watch?v=j4NTch4Shh8

This happens almost everytime I play the Einstein. When I fire it up, the einstein runs perfectly for a few minutes or hours. Than all of a sudden what you can see in the video happens.

Any advice would be nice.
Thanks, Sebastian.

 

[King Guitar]

Always start with the tubes. Sounds like one of the power tubes is bad and when it heats up it checks out. Look to see if any of them is glowing blue vs. orange.

Brad

 

[Sebwo]

No.
That's probably not the problem.
This happened with the older tubes too!

When I turn off the amp, and wait for about 10 min., the problem is gone and it does not appear until the next time (for example next day) I turn on the amp.

 

[duesentrieb]

Ruf Peter an:
09288/957664

 

[Peter Diezel]

Please send me the amp, but first take
a try outside the rack without pedals.

Thanks,

Peter

 

[Sebwo]

I did what you said Peter, but nothing changed. The problem still exists, so it's definitely not the rack-units or pedals.

If I send the amp, I have to be sure that the problem is not tube-related. Because it's too expensive and a waste of your little time to send it.
For the record: no tube is glowing extraordinary, changed all tube (pre and powertubes) and problem still exists, this "malfunction" exists for about a year or so and the period between the "attacks" gets shorter.

So either I'm not a lucky-guy and both sets of tubes (the old and new ones) aren't flawless or it's a bigger problem.

(Maybe it's a problem with my powersupply for the amp? Is it possible? I will try tomorrow another powersupply.)

 

[steve_k]

Sebastian:

Just a quick check before you post the head...I had the same thing with my Mesa Dual Rectifier last year. Problem was a tube fault caused by the tube socket in V1 pre-amp tube and the phase inverter tube. As there are no amp techs where I am, I was left to my own devices. Looking at the Einstein layout it looks like V1 and V3 are shared by both channels (as you have noise on both). The phase inverter tube in V6 will be shared as well. Not sure if you did this or not, but take an old tube and spray the pins down with contact cleaner and run them in and out of the socket several times on V1, V3 and V6. See if this helps.

You didn't mention if you had blown any fuses before?

You aren't operating any wireless bits in your kit are you?

Good luck!
Steve

 

[Sebwo]

Hey Steve,

that's a good advice. Cause I do think that the tubes are responsable.

No fuse ever blow. I destroy once a fuse cause I of my own "uncontrollable power" ( ). Replaced everything and the amp runs as hell.

No there are no wireless bits in my kit.

So just to come back to the tube-theory, I should kind of clean the contacts, right?

So If I use a 12ax7 in V6 instead of a 12AT7 (because I have no 12AT7 left) would the amp run as it is supposed to?

 

[steve_k]

yep, if it were me and i was doing some diagnosing on my own, with your particular problem, i would disconnect all the effects on the board and in the rack. reconnect your amp to speaker wire, then:

1) pull v1 (the one closest to the input).
2) spray the pins down with contact cleaner.
3) run the tube in and a few times (carefully).
4) replace it and turn on the amp.
5) check channels 1 and 2 for noises.

if this did nothing for you;

6) repeat all the above for v3.

if this did nothing for you;

7) repeat the same for v6 (you can temporarily use a 12ax7 for v6, but your at7 is probably ok.

if this didn't work and all the noise is still there,

8) turn the amp off and remove the fuse for the first pair of power tubes.
9) with your multi meter on 2ma range, put the red pin in the red hole and the black in the black hole (sing a few bars of black hole sun).
10) turn the amp to on (run not standby).
11) read the bias for the first pair of tubes. you should read 60-70 ma (this is x2 for the pair).
12) turn it off and replace the fuse.
13) repeat the above for the second pair.
14) you can adjust the bias from there too. unbiased tubes won't cause all that noise, but you could tell if you have a problem in one of the tube pots or a particular tube. if one of the pairs is out of wack, just remove one at a time to find the culprit.

you haven't left the amp on without a speaker (no load) plugged in have you?

if all this fails, go get drunk and wait on DHL to pick your amp up.

steve

 

[Sebwo]

Hey Steve,

thank you very much. It seems the problem is gone. I did what you said and up to now, it didn't happened again.
I will wait the next days to see if I can be happy for a long time.

Thanks and keep on helping guys like me

 

[Peter Diezel]

yep, if it were me and i was doing some diagnosing on my own, with your particular problem, i would disconnect all the effects on the board and in the rack. reconnect your amp to speaker wire, then:

1) pull v1 (the one closest to the input).
2) spray the pins down with contact cleaner.
3) run the tube in and a few times (carefully).
4) replace it and turn on the amp.
5) check channels 1 and 2 for noises.

if this did nothing for you;

6) repeat all the above for v3.

if this did nothing for you;

7) repeat the same for v6 (you can temporarily use a 12ax7 for v6, but your at7 is probably ok.

if this didn't work and all the noise is still there,

8) turn the amp off and remove the fuse for the first pair of power tubes.
9) with your multi meter on 2ma range, put the red pin in the red hole and the black in the black hole (sing a few bars of black hole sun).
10) turn the amp to on (run not standby).
11) read the bias for the first pair of tubes. you should read 60-70 ma (this is x2 for the pair).
12) turn it off and replace the fuse.
13) repeat the above for the second pair.
14) you can adjust the bias from there too. unbiased tubes won't cause all that noise, but you could tell if you have a problem in one of the tube pots or a particular tube. if one of the pairs is out of wack, just remove one at a time to find the culprit.

you haven't left the amp on without a speaker (no load) plugged in have you?

if all this fails, go get drunk and wait on DHL to pick your amp up.

steve

Thanks Steve !!!

Btw. You get a parcel