Vox AC15C1 dead reverb

[spleenharvester]

Annoyingly, my new (used) Vox AC15C1's reverb tank has suddenly given up. All I get when I turn the knob is an increasing 'ungrounded' sound. The RCA jacks appear to be seated firmly - what is likely the problem here?

EDIT: Can't get any reading between each side of the RCA jacks on DMM at all, springs all seem to be intact, haven't got chance to actually pull the tank out yet to have a look.

 

[spleenharvester]

Re: Vox AC15C1 dead reverb

Appears the output transducer on the tank is dead - the input (red connection, ground to signal) measures 77~ ohms. The output (white, ground to signal measurement) is open circuit. Is there any way to replace the transducer or is it just off to ebay for a new one?

EDIT: Okay, so I unplugged and replugged the wires a few times while trying to find the problem and suddenly I have resistance back, and the tank is working again (for now). Strange.

 

[zzmoore]

Re: Vox AC15C1 dead reverb

Some tanks have odd Ohms Readings.
Sounds like it was just a "dirty" connection between the RCA Cable and the RCA Jack on the amp.?
Seems like you are back in business. Though those transducers have Real Small wires. Lets hope the problem is gone for good. :beerchug:

 

[spleenharvester]

Re: Vox AC15C1 dead reverb

Some tanks have odd Ohms Readings.
Sounds like it was just a "dirty" connection between the RCA Cable and the RCA Jack on the amp.?
Seems like you are back in business. Though those transducers have Real Small wires. Lets hope the problem is gone for good. :beerchug:

It was actually the jack -> transducer connector that I unplugged and replugged. I have a feeling there's a dry joint somewhere and it's just going to pack up again. We'll see!

 

[James Rock]

Re: Vox AC15C1 dead reverb

If you have the money you should replace the reverb with an accutronics tank, you can search online about this mod. It (along with a few other mods) definately improved my brothers AC15C1.

 

[jeremy]

Re: Vox AC15C1 dead reverb

in my old fender amp the reverb tank has lasted more than 50 years so far. newer tanks dont seem any where near as well built, even "good" ones. ive had a handful fail over the past 5+ years. sometimes they can be repaired, sometimes ya need to replace em.

 

[spleenharvester]

Re: Vox AC15C1 dead reverb

Extended thread bump. I still have this amp. The reverb tank seems to come and go as it pleases now - sometimes it'll work fine for weeks, then completely pack up. Then inexplicably comes back weeks later.

Is this likely to be the tank itself or could the fault be somewhere elsewhere in the amp? I can't replicate getting it to work again via unplugging/replugging it.

 

[IM4Tone]

Re: Vox AC15C1 dead reverb

I suspect the tiny little wire from the transducer (inside the tank). Have you looked at it? If it were me and I couldn't re-attach the wire, I'd probably just buy a new tank. Only ~$20. HERE is one source.

 

[Chickenwings]

Re: Vox AC15C1 dead reverb

It is usually one of the fine wires that connect to the springs that wear out and break on reverb tanks. Have a close look and check for continuity.