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ADA Preamps => MP-1 Classic => Topic started by: Griphook on July 09, 2017, 11:44:50 AM

Title: Fast dying sound
Post by: Griphook on July 09, 2017, 11:44:50 AM
Heyho Guys,


it's been a while since I last posted sth.


I did not use my Classic really much, because the MP2 fits better in our Band context.
Recently I gave my Home-MP1 to our second guitarist, so the Classic came back to live.


The problem now is:
I have to put OD1 and OD2 to 10.0 to get as near as the distortion of the MP-1 at OD1=3 and OD2=7. This is at Distortion-Voicing
At Brown Voicing I only get a little bit of crunch, even with both ODs set to 10.
The Clean Tube does not even crack up really on the same settings.


Also I found out, that the sound is dying pretty fast.


Maybe some of you experienced similar issues?



Title: Re: Fast dying sound
Post by: Harley Hexxe on July 09, 2017, 11:53:15 AM
Does it do this on the SS voicing too?

   If not, more than likely, you need some new bottles in it.
Title: Re: Fast dying sound
Post by: MarshallJMP on July 09, 2017, 03:30:05 PM
I think Harley is right, try some new tubes first.
Title: Re: Fast dying sound
Post by: Griphook on July 10, 2017, 08:40:22 AM

Thank you

I Got no New tubes, but Ich recently Got another MP-1, which sounds great btw.
So I just swapped the tubes of the MP-1 and the Classic. The the MP-1 still sounds great and theProblem still persists, but it Got better. It seems, that  the Noise Gate Kicks in, but it is turned off definetly.


I Dont  get A Sound off the Clean Tube Voicing with OD1 and 2 Set to about 6. The Sound I get, when it comes out, sounds more like A fart...


No obvious Problems with S.S.


Sorry about All the capital Letters . My Smartphone thinks, This is german :facepalm:
Title: Re: Fast dying sound
Post by: Harley Hexxe on July 10, 2017, 09:13:17 AM
It's beginning to sound more serious than just new tubes.
Title: Re: Fast dying sound
Post by: Soloist on July 10, 2017, 10:44:06 AM
Sorry about All the capital Letters . My Smartphone thinks, This is german :facepalm:
Hahahahhaahaha.... that's funny!
Title: Re: Fast dying sound
Post by: Harley Hexxe on July 10, 2017, 11:56:06 AM
Sorry about All the capital Letters . My Smartphone thinks, This is german :facepalm:
Hahahahhaahaha.... that's funny!

  I've hit the language button by accident many times sending texts too. It's still funny  :lol:
Title: Re: Fast dying sound
Post by: MarshallJMP on July 11, 2017, 09:32:39 AM
I'm starting to the think it's a bad R151 resistor.

Check this topic   http://adadepot.com/index.php?topic=1879.0
Title: Re: Fast dying sound
Post by: Griphook on July 11, 2017, 10:22:57 AM
Thanks, I will check that asap  ;)


The Video posted sounds exactly like mine..
Title: Re: Fast dying sound
Post by: Griphook on July 12, 2017, 11:07:23 PM
I got about 2000 reistors laying around, but 180kOhm ain't one...

Hope i get one in the next days. I hope 1/4W 5% Tolerance is okay?
Title: Re: Fast dying sound
Post by: MarshallJMP on July 13, 2017, 01:40:21 AM
1/4W 5% is okay but try to get a metal film, these are more resistant to high voltage then carbon resistors.
Title: Re: Fast dying sound
Post by: Griphook on July 13, 2017, 07:48:43 AM
Alright, thanks  :thumb-up:
I ordered A bunch of resistors, the should arrive on monday.


In the meantime I desoldered R151 and measured IT around 1,4 MOhms.  :facepalm:  just slightly more than 180k  ::)
Title: Re: Fast dying sound
Post by: MarshallJMP on July 13, 2017, 09:34:10 AM
Well seems you found the problem. :thumb-up:
Title: Re: Fast dying sound
Post by: Griphook on July 18, 2017, 01:25:06 PM
Works like a charm again.

Thank you!  :thumb-up:
Now I only have to get the 499k Ohms Resistor.