How I solved a speaker problem in my Super Reverb

[Lewguitar]

Boy, this was really bugging me:

I put a set of four brand new Weber VST 30 watt P10Q's in my Super, wired it all up correctly and the amp sounded about 2/3 as loud as it did before putting in the Webers. :smack:

I checked several times to see if I'd wired a speaker out of phase but no. White wires to the red terminals and black wires to the unmarked terminals of each speaker.

But I knew something was wrong. The sound was just to thin.

So I took a 9 volt battery and soldered a wire to each terminal of the battery.

Then I unplugged the speakers from the output of the amp and using the battery, held the + wire to the + terminal and the - wire to the - terminal of each speaker...one at a time.

Watched the movement of each cone and the first three I tested all moved forward.

Got to the fourth speaker, did the same test and guess what? The speaker cone moved BACKWARDS.

Weber had labeled the terminals of one speaker backwards. The unmarked terminal should've been marked "red" and vice versa.

I scraped off the red dot, marked the other terminal red instead, wired that speaker up correctly and: WAHOOO! :dance:

The best Super Reverb I've ever owned is the best Super Reverb I've ever owned again! :laugh2: Lots of volume, lots of clarity, deep solid low end again, growly mids...everything that was missing is there again.

Thought maybe some of our younger members might benefit from that knowledge and testing method to check if your speakers are really in phase with each other...cuz mistakes happen, sometimes with the best of manufacturers.

Lew

 

[SoCalSteve]

Re: How I solved a speaker problem in my Super Reverb

Thanks for the info! That's why I enjoy coming here - all these handy little tips that only come from the experience of others.

 

[TheJangus]

Re: How I solved a speaker problem in my Super Reverb

Nice troubleshooting. You don't expect the manufacturer to screw up marking the terminals.

 

[Gearjoneser]

Re: How I solved a speaker problem in my Super Reverb

I've heard of that test, but never tried it. I'm assuming there's NO risk to the speaker with such a small amount of current, right? I love Super Reverbs. I guess its the trademark Fender tone with the room-filling power of a halfstack.

 

[Artie]

Re: How I solved a speaker problem in my Super Reverb

Some of the same guidelines for electronics troubleshooting match driving tips:

Expect the unexpected.

Nice reminder, Lew.

 

[SlyFoxx]

Re: How I solved a speaker problem in my Super Reverb

Good ear and good catch. The 'ol 9 volt battery trick.

Just make sure you only close the circut for a split second though....speakers don't like direct current too much.

Having a single speaker's polarity reversed can also cause damage at high volumes. I guess the sound waves fighting each other can cause the cones to self destruct. Probably more of a problem with bass bins in high volume PA arrays.

 

[Artie]

Re: How I solved a speaker problem in my Super Reverb

Just make sure you only close the circut for a split second though....speakers don't like direct current too much.

As long as you don't exceed the wattage of the speakers, its not too bad. However, that is good advice.

9 volts, into an 8 ohm speaker is about 10 watts.

 

[Lewguitar]

Re: How I solved a speaker problem in my Super Reverb

9 volts, into an 8 ohm speaker is about 10 watts.

I didn't know that. Good info guys...Thanks!

When you put 9 volts DC on the speaker the cone moves but stays there until you remove the battery again. So I only held it there for a second...the whole idea is to watch the speaker cone move and see whether it goes forward or backward.

 

[skyydogg01]

Re: How I solved a speaker problem in my Super Reverb

I didn't know that. Good info guys...Thanks!

When you put 9 volts DC on the speaker the cone moves but stays there until you remove the battery again. So I only held it there for a second...the whole idea is to watch the speaker cone move and see whether it goes forward or backward.

this is called DC Offset.