Vox AC30CC1 a simple fault
This Vox AC 30 model is a lightweight one speaker version and the speaker is a special light weight design. The amp circuitry is the same. Its big disadvantage is no lovely Alnico Blue speakers
The owner reported the amp as sounding weak and intermittent.
I played detective and asked a number of questions.
When was the amp last used?
It has not been used in a number of months. It is my spare AC30 and I store it in the garage.
There was the key clue. Us poor folks in the UK have to endure a cold wet miserable climate in the winter months. Sometimes in the summer too ! The roads are covered in salt especially in the northern half of the UK. I already knew the owner lived close to the North Sea.
On the back of these amps are a set of slider switches. One for the speaker impedance setting,, one for the FX loop bypass and one for the the bias resistor setting.
Slider switches often develop bad contacts through oxidisation as they are open to the atmosphere. Add in a salt covered wet car being parked in the garage and the salty North Sea and you have the perfect conditions for oxidation.
The weak sound made me suspect the bias resistor slide switch. It was duly sprayed with contact cleaner and the amp sprung into life.
I live next to the North Sea and see a lot of oxidation effects. It is common to have folks reporting their spring reverb is causing hum or not working and the cure is usually to remove and re-insert the phone plugs on the reverb pan and on the connections going into the amp.
The worst case of garage corrosion was on a Peavey Classic 30 where the copper wire in the speaker coil had turned from shiny copper to blue powder due the damp.
So my message is ‘ NEVER STORE A GUITAR AMP IN THE GARAGE”
Unless of course you want to add to my bank account
We do have some nice tube kits for these amps . We tend to fit Tung Sol preamps and Sovtek EL84 for rock genres and JJ for country and 60’s tones.