It is currently Mon Mar 16, 2020 8:53 pm

All times are UTC - 7 hours



Post new topic Reply to topic  [ 8 posts ] 
Author Message
Post subject: Vibrolux Reverb Reissue fuse blowing
Posted: Mon Sep 22, 2014 7:08 pm
Offline
Amateur
Amateur

Joined: Mon Nov 01, 2010 10:31 pm
Posts: 154
Having an issue with a reissue vibrolux reverb.. Power and standby switches turned on and the amp pilot light is lit.. Then about 5 seconds after that thud! And the fuse is blown.. Any pointers?

Thanks
Pooch


Top
Profile
Fender Play Winter Sale 2020
Post subject: Re: Vibrolux Reverb Reissue fuse blowing
Posted: Mon Sep 22, 2014 7:40 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Tue Jun 29, 2010 1:20 pm
Posts: 9640
Location: Indiana
Remove the output tubes (and rectifier tube?) and try again. Likely a bad tube.

_________________
---> "The amp should be SWITCHED OFF AND UNPLUGGED before you do this!" <---

Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.


Top
Profile
Post subject: Re: Vibrolux Reverb Reissue fuse blowing
Posted: Mon Sep 22, 2014 7:45 pm
Offline
Amateur
Amateur

Joined: Mon Nov 01, 2010 10:31 pm
Posts: 154
I was thinking that exact thing.. But don't understand as to why that would make the issue go away.. I will check and post the outcome.. (this particular reissue amp has no rectifier)


Top
Profile
Post subject: Re: Vibrolux Reverb Reissue fuse blowing
Posted: Mon Sep 22, 2014 9:07 pm
Offline
Amateur
Amateur

Joined: Mon Nov 01, 2010 10:31 pm
Posts: 154
Power tubes were the culprits... Thanks again!


Top
Profile
Post subject: Re: Vibrolux Reverb Reissue fuse blowing
Posted: Tue Sep 23, 2014 1:40 am
Offline
Rock Icon
Rock Icon
User avatar

Joined: Fri Feb 05, 2010 4:31 am
Posts: 14049
Location: Province de Québec, Canada
michaelbpuccio wrote:
Power tubes were the culprits... Thanks again!



New power tubes need a bias check.

Cold bias = poor sound .

Very hot bias = it shortened tube life


Top
Profile
Post subject: Re: Vibrolux Reverb Reissue fuse blowing
Posted: Tue Sep 23, 2014 10:58 pm
Offline
Amateur
Amateur

Joined: Mon Nov 01, 2010 10:31 pm
Posts: 154
This amp is the Reissue and is fixed bias... Would have to install a pot and everything that goes with that for it to be adjustable.. To me it makes no sense that Fender would make this amp fixed and the Deluxe RI an adjustable as they are very similar.. Sometimes they just don't make sense to me...


Top
Profile
Post subject: Re: Vibrolux Reverb Reissue fuse blowing
Posted: Wed Sep 24, 2014 1:17 am
Offline
Rock Icon
Rock Icon
User avatar

Joined: Fri Feb 05, 2010 4:31 am
Posts: 14049
Location: Province de Québec, Canada
Most of the amp company don't put adjustable bias


Top
Profile
Post subject: Re: Vibrolux Reverb Reissue fuse blowing
Posted: Wed Sep 24, 2014 3:29 pm
Offline
Rock Icon
Rock Icon
User avatar

Joined: Tue Jun 29, 2010 1:20 pm
Posts: 9640
Location: Indiana
michaelbpuccio wrote:
This amp is the Reissue and is fixed bias... Would have to install a pot and everything that goes with that for it to be adjustable.. To me it makes no sense that Fender would make this amp fixed and the Deluxe RI an adjustable as they are very similar.. Sometimes they just don't make sense to me...


Once again, "fixed bias" just means that a negative DC voltage is applied to the tubes control grids, it still must be set for each set of output tubes. It does not mean that the bias can not be changed. It might not have a bias adjust pot, but has a bias resistor that can be changed (there are fixed bias amps with adjustment pots). The bias for different output tubes on a fixed bias can vary wildy from one set to the next, so do yourself, and your amp, a favor and check/set the bias.

The biasing scheme that needs no adjustment when changing tubes is "Cathode biased", meaning pretty-much self-biasing. Your preamp and PI tubes are Cathode biased.

_________________
---> "The amp should be SWITCHED OFF AND UNPLUGGED before you do this!" <---

Por favor, disculpe mi español, no se llega a la práctica con mucha frecuencia.


Top
Profile
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 8 posts ] 

All times are UTC - 7 hours

Fender Play Winter Sale 2020

Who is online

Users browsing this forum: No registered users and 2 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum

Search for:
Jump to: