ADA Depot - A Forum To Support Users of ADA Amplification Gear

Please login or register.

Login with username, password and session length
Advanced search  

News:

Lets get Technical > All Things Tube All about preamp and power amp Tubes.

Pages: [1]   Go Down

Author Topic: Hi pitch beep gohst sound on MP1 3TM, please help!  (Read 6214 times)

0 Members and 1 Guest are viewing this topic.

j4q0

  • Newbie
  • *
  • Offline Offline
  • Posts: 31

Hello all,
I was wondering if someone can chime in about this problem.
There is a high pitch sound coming from my ADA MP1 3TM that only manifest itself on 3 of my guitars when the volume pot is all the way down (?!)
These guitars have different pickups and different pots, though they are all mini pots (2 of them DPDT). My other guitars don't show this problem and some of them have the same pickup as one of the ones with the problem, and those guitars not showing the high pitch sound have both mini and full sized pots.
I'm completely lost at why this is happening.

You can hear this weird sound in a recording I made with my phone:
https://soundcloud.com/r3set-1/beep/s-AgNaj

I'm far from being very knowledgeable in electronics but I do know the basic stuff and how to solder electronics on my guitars (not perfect though ;D).
I hope somebody can help me with this problem as it gets really annoying.

Cheers.
Logged

MarshallJMP

  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 4702
    • marshalljmpmodshop.net

Could be the pots are bad.Sometimes the wiper of the pot can loose contact so the input of the mp-1 is floating and this can cause the high pitched sound.Try to replace one pot and see if this helps.
Logged

j4q0

  • Newbie
  • *
  • Offline Offline
  • Posts: 31

Thanks MJMP.
I also thought the pots could be bad, although this sound doesn't show up when using another preamp or my 5153. Given this, do you think it could still be the pots?
In any case I'll change the pots for sure, I just have to order new pots and wait until they arrive.
Logged

MarshallJMP

  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 4702
    • marshalljmpmodshop.net

Well replace them first and see what happends and we'll take it from there.
Logged

j4q0

  • Newbie
  • *
  • Offline Offline
  • Posts: 31

Signed in to report the issue solved and I didn't realize it was 6 weeks ago :P Too much work, need more play  ^-^

Although it was a simple and easy problem I really appreciate MarshallJMP taking the time to help us all.

Logged

rnolan

  • Administrator
  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 5998

 :whoohoo!: Glad it's solved  :thumb-up: go MJMP  :wave: :bow:
Logged
Studio Rig: Stuff; Live Rig: More Stuff; Guitars: A few

MarshallJMP

  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 4702
    • marshalljmpmodshop.net

So was it the guitar pot?
Logged

j4q0

  • Newbie
  • *
  • Offline Offline
  • Posts: 31

I wanted to change the pots on 2 guitars for a push/pull pot and after the new pots were installed the problem was gone.
What is curious is that yesterday night I played the third guitar that showed that same problem and is not showing it anymore. I didn't change anything on the guitar, though I did some changes on the rack, made new MIDI cables and rearranged the power strip and power supply (coiled and tied their cables) of my Rocktron units.

Any idea if this could have contributed to the problem?

Logged

MarshallJMP

  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 4702
    • marshalljmpmodshop.net

Could be that it was the cables.Strange things can happen in racks,sometimes you just need to call the ghostbusters >:D
Logged

rnolan

  • Administrator
  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 5998

I suspect midi cables (not part of audio chain) would make no difference re beep (but who knows), but power cables/strip well that's another story. Maybe the pot cleared in 3rd guit ? I'm with MJMP, call the ghostbusters LOL
Logged
Studio Rig: Stuff; Live Rig: More Stuff; Guitars: A few

MarshallJMP

  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 4702
    • marshalljmpmodshop.net

Well if you hold a midi cable near an audio cable you can sometimes hear some noise,but not a beep sound.
Logged

rnolan

  • Administrator
  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 5998

Good point MJMP. Here a thought bubble, when you coil up a power cable and cable tie it off to tidy up your rack, don't these cause inductance loops ? So ideally you should cut your power cables to minimum distance. I'm assuming the various units filter this out in their power supply circuit ?
Logged
Studio Rig: Stuff; Live Rig: More Stuff; Guitars: A few

MarshallJMP

  • Superhero Member
  • ******
  • Offline Offline
  • Posts: 4702
    • marshalljmpmodshop.net

Well yes but the inductance will be so low it won't affect anything,unless you have 100m of cable.
Logged

j4q0

  • Newbie
  • *
  • Offline Offline
  • Posts: 31

Good point about coiling up the power cables.
The beeping sound was before coiling up the cables, at that point the cables were just hanging from the back of the rack in a very
"tidy untidiness" out of the way of the units themselves.

Logged
Pages: [1]   Go Up