Diezel Einstein combo problem

[guitar_face]

Hey there

-- I've got a problem where my Einstein emits a metallic hiss some time after notes are played. It seems to affect how long a note sustains too, as the sound seems to cut out prematurely and get replaced with a nasty hiss. It's especially obvious when I let chords ring out in Texas mode but I'm sure it's prevalent whenever there's any distortion.

I have a good tech where I live that I trust to undergo any maintenance, but I thought I should post here to make sure that there's actually something wrong and I'm not tripping balls for lack of a better term. Also it would be nice to have some input from Mr Diezel as to what the problem might be.

The problem is that I don't have any recording gear. I've tried recording with a phone mic, but as expected it doesn't do a very good job at all of recording distorted guitar tones. I will try a video camera tonight and hope for the best.

-- Any suggestion for a cheap mic in the event that the video camera doesn't capture the sound properly?

Thanks for any input anyone

 

[TooL46_2]

From what you're writing it seems to me that your preamp tubes might be experiencing the phenomenon called microphonics. If that's the case -- replacing the tubes (or only the one in the first stage) should help you remedy that. Tubes in combos are usually more susceptible to microphonics because of the neighborhood of the speaker and the vibrations it produces. Yet, I bet Peter looked into that during the design stage and in your case it's probably just a faulty tube.

I might be wrong, though, and Peter will probably give you a better advice Good luck anyways!

 

[guitar_face]

Thanks for the response. This problem has been going on for a while actually (as long as I remember having the amp really) but I tried to ignore it. Now that I'm getting into more in between sounds and using the volume knob and dynamics to control gain it's getting slightly annoying.

I doubt it's a tube problem; last year I retubed my whole amp (I know, slight overreaction ) just in case it was the problem and nothing changed.

Hope will be able to demonstrate the sound with a clip soon-ish.

 

[guitar_face]

Finally got a relatively decent sound clip of it. The sputtering I'm talking about is pretty obvious here and the strums in the end emphasize it well - 99% of this is not camera distortion.

So, 2 question:
- This is not normal, am I right?

- Any insights as to what it might be? I realise I'm asking a lot in wanting a diagnosis via youtube, but any ideas would be nice.

Thanks

 

[guitar_face]

bump

So over 50 views of the thread and no one wants to answer my first, extremely simple question. No Einstein owners listened to the clip? Turn the volume up if you think you're not hearing the noise I'm talking about.

- Does your amp make that hiss/static/sputter after notes or not??

Thanks

 

[TooL46_2]

Try playing with reverb knob. See how it sounds with Rev fully cranked and turned off. Maybe there's sth around this. That's where I would probably start after seeing your vid.

Hope this helps a bit...

 

[guitar_face]

Never really thought about that, cheers man. Unfortunately while it does affect the noise slightly, it's still present no matter where the reverb knob is set.

I'm not sure how to fully turn off the reverb as for some reason my amp didn't come with a reverb footswitch jack; there's a plastic cap covering where this socket is supposed to be.

Thanks again for the response.

 

[gibson08]

Hello, Sorry I do not own an Einstein combo, but I have played a head unit pretty extensively, so I will try and help(I said TRY!) What channel/mode was your video clip played in?? So you changed the tubes trying to fix the problem? In other words the problem was def there before? and the same after? Just reading your complaint before I heard the clip it sounded like you had maybe a bad voice coil in the speaker, have you tried another speaker/ext cab? Hopefully someone else will also chip in, because I am sure there are more qualified people here than me! I am sure either Peter Diezel or Mark2C will answer and help you, they always do,,hang in there!

 

[guitar_face]

Hello, Sorry I do not own an Einstein combo, but I have played a head unit pretty extensively, so I will try and help(I said TRY!) What channel/mode was your video clip played in?? So you changed the tubes trying to fix the problem? In other words the problem was def there before? and the same after? Just reading your complaint before I heard the clip it sounded like you had maybe a bad voice coil in the speaker, have you tried another speaker/ext cab? Hopefully someone else will also chip in, because I am sure there are more qualified people here than me! I am sure either Peter Diezel or Mark2C will answer and help you, they always do,,hang in there!

Thanks for the input! Yeah the sound was definitely present before I fully retubed the amp; I even ordered a low noise/microphonics 12ax7 for V1 just in case but didn't help the situation. I wish I had an extension cab to test out the whole speaker problem theory - might have call the tech eventually and ask if he's got a cab to try out.

The clip was in channel 1 mode 2/Texas mode by the way.

 

[MARK2C]

Try a new speaker.

If that does not fix the issue, look at the 22uf/500V filter caps to see if they are leaking any yellow goo.

 

[bronz79]

Try a new speaker.

If that does not fix the issue, look at the 22uf/500V filter caps to see if they are leaking any yellow goo.

I agree with you Mark,
to my ears it don't seems a microphonic preamp tube feedback.

 

[guitar_face]

Thanks, I'll definitely get hold of a cab at some point to see if it's the speaker. I'll look at the guts for now.

 

[gibson08]

Hello, Sorry I do not own an Einstein combo, but I have played a head unit pretty extensively, so I will try and help(I said TRY!) What channel/mode was your video clip played in?? So you changed the tubes trying to fix the problem? In other words the problem was def there before? and the same after? Just reading your complaint before I heard the clip it sounded like you had maybe a bad voice coil in the speaker, have you tried another speaker/ext cab? Hopefully someone else will also chip in, because I am sure there are more qualified people here than me! I am sure either Peter Diezel or Mark2C will answer and help you, they always do,,hang in there!

Thanks for the input! Yeah the sound was definitely present before I fully retubed the amp; I even ordered a low noise/microphonics 12ax7 for V1 just in case but didn't help the situation. I wish I had an extension cab to test out the whole speaker problem theory - might have call the tech eventually and ask if he's got a cab to try out.

The clip was in channel 1 mode 2/Texas mode by the way.

OK, yeah at this point you need to try another speaker/ext cab before you go any further. Good Luck and let us know what happened.

 

[guitar_face]

Well it's not a speaker problem; it's a bit more subtle with a Marshall 4x12 but it's definitely still present.

I took a few gut shots of things which may be suspicious or may be me having no idea what I'm looking at... does the yellow stuff under these parts qualify as 'yellow goo'? I didn't notice any capacitor leaks as they normally appear according to google/wiki.

thanks

 

[TooL46_2]

Check this thread -- that's the yellow goo with electrolytic caps Mark is talking about.

Photos do not show that properly, but I think what you're calling yellow goo is simply a glue under the caps to keep them in place.

 

[guitar_face]

Heh, kinda figured; if that was what MARK2C was talking about then my amp would be truly screwed.

Just opened her up again, all the caps look fine actually.

Hmm , will definitely take it to the tech anyway. I really hope he figures it out.

 

[TooL46_2]

Have a read around this web. Maybe something will help you.

 

[gibson08]

Heh, kinda figured; if that was what MARK2C was talking about then my amp would be truly screwed.

Just opened her up again, all the caps look fine actually.

Hmm , will definitely take it to the tech anyway. I really hope he figures it out.

That sucks, a speaker would have been an easy fix,,well i am sure your tech will get it figured out for you. Good luck and let us know what happened!

 

[PBGas]

-- I've got a problem where my Einstein emits a metallic hiss some time after notes are played. It seems to affect how long a note sustains too, as the sound seems to cut out prematurely and get replaced with a nasty hiss. It's especially obvious when I let chords ring out in Texas mode but I'm sure it's prevalent whenever there's any distortion.

I had this problem.....I guess it was similar. It would almost be like some unwanted distortion or a strange sound. I attributed it to my different effects on my pedal board that were causing it. It was really obvious with the delay on. Hard to explain the sound though......

Haven't had this issue with my Herbert though.....I hope you get it fixed!

 

[guitar_face]

Thanks everyone; it's with the tech and I've let Peter know that the tech will get in touch with him if he needs advice. Yeah that sounds about right PBGas, though it's present with or without effects for me. It's most obvious in mode 2 with gain at about 12 o'clock, and the hiss/fizzle starts as the distortion begins to fade.

Will keep you all posted, and with any luck I'll eventually be able to tell you what was wrong.