my 73 silverface deluxe reverb just died!

[Skiroy]

Hey guys,my amp just stopped making sound. You know when you turn the amp on you here the noise floor out of the speakers? Yeah it doesnt even do that. I was playing for 3 hours with a bunch of different pedals doing a huge shooutout.

I know its not the preamp tubes and from what I was told the amp will still work even with the reverb, recovery reverb and tremolo tubes taken out so it cant be them. I also swapped the phase inverter 12ax7 tube with no luck. The fuse is not blown and the main transformer is getting power.

So it has 2 power tubes. is it one for each channel or are they in series? Im trying to rule them out. I tried measuring voltage on some resistor and caps in the preamp circuit and there is nothing. The power amp tubes come after the preamp section right the the problem is before the preamp sections and it affecting both.

Is it neccessary to pull the tubes to test voltages of the transformers? And how do I know what voltages to look for?

And help here? Could it be the big rectifier tube?

If one power amp is out will it cause this or is each power tube for each channel?

[dconeill]

The only help I can be is to tell you that the power tubes are a push-pull circuit, that the device only has a single power amplifier section. Best thing to do is to take all the tubes to a testing machine and see if they're all OK.

Easiest thing to do is to swap out the power tubes with another set that is known to be good, but if something up-circuit from the power tubes has caused them to blow then you might put the testing power tubes at risk.

In the old days you could go to the neighborhood drug store and test the tubes on a big ol' tester. Alas ... Do you know any places that have a tube tester?

[StephaninMelb]

I sense you don't have much electronics background with tube amps and with voltages in the 300 to 500V range it is necessary to be extra careful.

Your Back Pocket – The Most Important Tube Amp Tool

When working inside a live amp Put your Second Hand in your Back Pocket. When working with one hand if you get a jolt it is going to sting. If you have your second hand touching the amp chassis or other ground point the current path will flow through your heart. Chances are you are doomed if you take a high voltage jolt with both hands completing a circuit.

You will be working around 300-500V circuits!

Other Safety Tips

• Use a nylon potentiometer screwdriver
• Alternatively, use a metal tip insulated screwdriver
• If you drop your tool while the amp is on - don't reach for it
• If you drop your tool turn the amp off and discharge the caps before attempting to remove tool
• Don't leave your amp unattended with the enclosure open if children are around
• Don't connect/disconnect test leads with the amp on
• Don't touch any of the circuitry outside the potentiometer with the amp running
• Rubber soled shoes/rubber mats can provide additional safety
• Do not touch any other plugged in electrical item or pipes while you are working

[T Prior]

Quite frankly, you should not pull the chassis and mess around with looking for voltages if you are not familiar with the amp and electronics.

+430 DC volts inside...( approx for Deluxe Reverb) you will get hurt. 117VAC on the primary of the power transformer as well, you will get bit...

Yes it could be a tube or the rectifier tube. With the amp power on..are all the tubes lit , not glowing, filaments on, you may have to dim the lights in the room to see each one.

IF you want to do something simple and safe, go get a 12AX7, a 6V6 and the rectifier GZ34...don't pull the chassis.

Swap the rectifier...check the amp

Swap ONE 6V6 ..check the amp

Swap the other 6V6..check the amp

Starting from the opposite end, swap the 12AX7, check the amp..do it in the first three positions..

If this doesn't help I would recommend bringing the amp to a technician.

[mistermullens]

Basically, what Stephan is saying is...DON'T TOUCH THAT AMP! Just kidding. Stephan has had some great posts, and always gives good advice.

My advice is to find a good amp tech in your area. I've got a great guy in Atlanta I really trust. Should be pretty easy to find one in FL.

[alnicopu]

Originally Posted by mistermullens

Basically, what Stephan is saying is...DON'T TOUCH THAT AMP! Just kidding. Stephan has had some great posts, and always gives good advice.

My advice is to find a good amp tech in your area. I've got a great guy in Atlanta I really trust. Should be pretty easy to find one in FL.

There's a couple of guys that have a shop down the road from you in Gulf Breeze. Don't know anything about them but I grew up there and surfed on Gulf Breeze High's surf team in the late 70's. Let me know how and where they are if you try them out. I've stumbled upon them once or twice.

[adjason]

Time to find a tech

[JohnS]

I agree with the back pocket comment, except that I mean the one you keep your wallet in. Take it to a good tech. Good luck.

[CoolBlueGlow]

Also, Don't want to overlook the obvious. You SURE you didn't just blow a speaker? 3 hour pedal fest means lots of thumps pops, pedal changes, and heavy overdrive, which is a speaker killer.

Sometimes they blow and just go silent, you know.

CBG

[Skiroy]

Originally Posted by CoolBlueGlow

Also, Don't want to overlook the obvious. You SURE you didn't just blow a speaker? 3 hour pedal fest means lots of thumps pops, pedal changes, and heavy overdrive, which is a speaker killer.

Sometimes they blow and just go silent, you know.

CBG

Holy crap. Its the speaker. I just bought that speaker. I would think you could play it for hours. So do you have to turn down the amp ever time to change any cables,guitars ect.? I didnt realize this would blow a speaker. is it also bad for the amp?

I have a speaker but it has a tiny hole in it from a screw. What is the best thing to seal this hole. Marine silicon?

[CoolBlueGlow]

Hi Skiroy,

Yep - blown speaker...that's what I was afraid of.

re: is a long session of rocking out bad for the amp/speaker?

It is not "bad" for the amp, you are simply "using up" the amp's capability. Eventually, you'll need to retube it. That's normal wear and tear.

re: is it bad for the speaker?

Well, a lot depends on the speaker. Big heavy duty over-rated speakers in a Deluxe reverb are generally o.k. with this kind of abuse. Unfortunately, many of those heavy duty high power jobs don't sound so good in a DR. Their inherent "heavy duty design" can strangle them for lower wattage applications. (JBL excepted)

However, nominal wattage speakers (like a 25 Watt rated speaker in your 22 Watt DR) operated at or near their limit for many hours can and do fail with alarming ease. The thumps and pops of pedal changes are VERY high transient loads at very low frequencies. Those are speaker killers when you're dealing with a speaker operating at or near it's rated power.

Further, operating an amp at full power for several hours, especially with highly overdriven/distorted signals really heats up the voice coil in your speaker. (That 22 Watts of DR firepower gets turned into heat...in your speaker's voice coil.) As you heat up the voice coil, the resistance of the wire in the voice coil rises. Less efficient, you turn it up, more heat, etc. It's a vicious cycle.

The wire in your voice coil is 34 gauge wire. It is dissipating the vast majority of the 22 watts that your DR is putting out. It is VERY thin. VERY fragile. When heated and cooled and heated again and again, while being severely vibrated, it work hardens. That can lead to embrittlement failures, which make loudspeakers go "suddenly" silent.

I suggest that you check around here on the forum for recommendations for speakers for your DR. Sounds like you're a pretty heavy duty user.

Good luck with it,

Cheers,
CBG

[Skiroy]

thnaks man. I have a weber 150f I am going to try out.

Is regular silicon the best thing to glue a little hole in a speaker? I was putting it in a amp and a screw poke a hole in it. It has a flap that folds over to cover the hole I just need to glue it to keep the flap in place and prevent the hole form ripping worse during playing.

[supersam]

Originally Posted by Skiroy

So do you have to turn down the amp ever time to change any cables,guitars ect.? I didnt realize this would blow a speaker.

I wouldn't leave the signal hot while changing guitars/cables, if for nothing else than because that loud pop and scratch is really an awful sound to my ears. I use a boss tuner pedal when changing out guitars because it mutes the signal when you step on it. You could also pull the cable out of the amp halfway when changing out guitars and doesn't pop for some reason. I'm not sure why it doesn't pop when taking the cable out of a turned up amp though.?

[jmaul]

Originally Posted by Skiroy

Is regular silicon the best thing to glue a little hole in a speaker?

No. Rubber cement (perhaps with thinner) and tissue paper, a few layers.

[StephaninMelb]

Here is text by late Ted Weber of Weber Speakers on patching small tears / holes in a speaker cone:

"If it has doping on the surround, use acetone and a cloth to remove as much of it as you can around the hole. Spread some Elmers Glue around the hole. Lay down a small piece or tissue paper. More glue, more paper. Do that 5 times and make sure the paper is smoothed out all over and saturated with glue. Let it sit overnight."

You only need to remove the doping if the hole / tear is in the doped area. Dope is usually colored (red, black, etc.) and shiny. Speaker are made both with doped and undoped edges.

People have also used in place of tissue paper:

• Coffee filter
• Blue shop towel
• Hem reinforcement material
• Napkin
• Toilet paper
• Old speaker cone material

An even older fast method going back to 1960s is to use clear nail polish & tissue paper in place of Elmers Glue. This was done at gigs as many girls carried around clear nail polish and it dries in just a few minutes.

For long rips people have used: A bead of 3M Black Super Weatherstrip Adhesive

Other adhesives that work:

• Super glue
• Contact cement
• Wood glue

[Wally]

To add to what Cool Blue Glow has to say about pushing an amp hard and speaker failure, I would say this. Teh amp does not have to be run to the max of its output to cause a failure that is related to the amp's ability to disspate heat. One need only run a distorted signal at the speaker. Distortion causes the speaker's cone to be at full excursion...without the ability to cool itself. A 5-watt amp pushed hard or a distortion pedal through an amp that is not generating max power can burn a speaker down if the rig is run at distorted levels for extended periods of time.

[CoolBlueGlow]

Wally's right.

The "squarer" the signal ("squarer" as in more clipped...as in "raging overdrive tone") the more time the speaker's voice coil spends working like a toaster merely dissipating DC energy (as opposed to moving air). It's a love hate situation, if you get my drift. We love the crunchy tone, but too much without a break does bad things to voice coil.

Compared to SS amps, tube amps don't do a really bang up job reproducing square waves, mostly due to output transformer limitations. Nevertheless, they can still do that crunchy square wave thing quite well enough to turn your speaker into a toaster. That will soon toast it...as you have unfortunately discovered.

Cheers!

CBG