Menu

Show posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.

Show posts Menu

Messages - agdrago

#1
Amplifier Discussion / Re: Help with diagnosis...
September 01, 2009, 09:42:51 PM
Thank you! I Googled an Yahoo'ed and found no schematics on the web so I cracked and ordered one from Roland.

If this is the same service manual as I ordered (probably is) they've got some nerve given what they charge for it.

#2
Amplifier Discussion / Re: Help with diagnosis...
September 01, 2009, 02:36:05 PM
Thanks for the response.

I checked that the speaker was not the issue by playing through a remote cabinet. Unfortunately the same behavior was noted playing through known good speakers.

Performing the test mentioned above helped me to identify that a component of the ticking sound is not coming through the speaker but instead from a component in the amp. I'll remove the amp from the cabinet and see if I can identify what component that sound is coming from.

I do not have access at this time to an oscope or a signal generator (other than a guitar/bass/keyboard).

I have ordered a service manual which will be here later this week. I will post the schematic for the power section if I can provide additional info on the state of the amp.

Thanks again.
#3
Amplifier Discussion / Help with diagnosis...
August 31, 2009, 01:32:21 PM
I have a Roland Blues Cube 60. The amp works perfectly when it is first turned on, but then as if by a function of how hard it is driven and how long it has been on it develops a ticking sound reminiscent of a playing card against the spokes of a bicycle wheel. The sound of the guitar can still be clearly heard as well as the ticking noise.

The cadence of this tick changes based up on the attack of notes played. It also occurs in both preamp channels as well as if the guitar is fed just to the power amp via the effects return.

The guaranteed way to cause the ticking is to hit a 6th string 5th fret or a 5th string 7th fret harmonic. As the note decays the ticking slows and then abruptly disappears.

Any and all help is appreciated.

Thanks,

- Grady