Crate GLX65 Question; Working Amp w/ no Sound from Speaker

[itscali]

Hello, and thank you for looking into my post. I have a Crate GLX65 combo which I have had for a few years. The amp has always worked great until I connected an extention speaker one session. I connected the amp up to a Marshall 4x12 cabinet that it was setting on top of in the session area, and the amp worked fine for that session. After getting home and trying to use the amp again, there wasn't any sound from the resident speaker. I checked the physical speaker connections (which were good) and anything else that I could inspect without opening up the amp to the electronics inside. I hooked another external speaker up to the amp and it worked great. I also hooked up another amplifier directly to the speaker that is in my GLX65... and my speaker works fine. The only thing I can think is that there was a glitch with the External Speaker switch where the amp still thinks that is where sound output should be going. Would sure appreciate any input that anyone can give me as I love the amp and really don't see it being a cataclysmic issue (although it certainly is something that I can't figure out on my own to date). Thank you again for your time looking into my delima

[Fragger]

The easiest thing to try first is spray a little DeoxIt D5 on a guitar cord end and plug it in and out in the Ext. Speaker jack, repeat.

I noticed in the user`s manual for this amp the combo speaker is in series with Ext. Speaker jack so both the combo speaker and the external cab. in theory would sound together.

Is that how it worked?

[Jazz P Bass]

Crate GLX65

I looked at the owners manual.
Page 7 has a block diagram of the amplifier.
Sure enough, the external speaker jack has a normally closed contact that completes the internal speaker signal path.
Something is amiss with that ext. spkr jack.

[justjunkymail]

Loosen the nut on the external speaker jack and wiggle it around while playing the amp. If sound cuts back in (or out), it's a strong indication of a failing solder connection on that jack.

[Enzo]

Well now, that is a nice simple trick that doesn;t require access to the innards. I never thought of loosening the nut as a test procedure, I am so used to working inside. Good idea.

[pecorporation]

If the Deoxit D5 doesn't work, the extension jack shorting tabs are probably stuck open preventing signal flow, in which case a new jack would need to be installed for reliable operation.

[chipprogr]

2nd that to pecorporations comment.. the jack is best replaced. the spring strength of the internal contact weakens over time and wont allow enough pressure to keep the circuit closed to pass signal. bending usually is only a temp fix and for the low cost of a jack, And since youve got it apart..replace it.

[itscali]

Wow you guys are awesome, thank you so much for the information. In a way, all of you were correct in your assumptions.

I connected the amp up to my Marshall cabinet once again to verify that the amplifier was at least putting out signal. It did put out noise in series to the Marshall cab and resident 12" as Fragger mentioned. Of course without the extension speaker plug inserted, there was no sound from the amp as before. I loosened the external nut for the extension speaker plug and wiggled it around while a guitar was plugged in and the power was on as Justjunkymail had suggested, but still nothing.

The removable recessed handle in the top made a very easy access point to get to this plug block, so I removed it as well as the nuts holding the plug block in place. On closer inspection of the removed plug block, I noticed there to be (2) metallic tongs that draped over the single plug enclosures, one for each contact on an inserted plug shaft. The inner-most tong had a decidedly large gap from its contact point, unlike the other tongs of the plug block. So, when a plug is inserted, divets on the tong itself pick up contact against the inserted plug shaft, and then series the sound to both the external and internal speakers. When the plug is removed, the tong in question would not fully rest down on its contact again, making for a broken connection to the resident speaker. Seeing this I remembered that at the time all this occurred, I used a rather short extension cable to get to the cabinet I used and recall it even pulling back on the amp a bit. This must have cause the inner tong to deform more than it would if it were not under this undo stress.

After looking at the plug block for a bit, I really didn't see a way of getting the tong-end itself to reshape it to it's correct position. Then, I plugged in a cable and noticed that the tong end was raised enough from the contact that I could simply push down on the end of the tong with a tool and bend it down. Once the cable was removed, PRESTO, the contact was once again made and I saved buying a new part. I followed suit with all the other plug block tongs (Effects Loop) as well so that all the connections would be sound. After reassembly, my awesome amp works again .

Thank you very much to everyone that replied. I know it was not a major problem, but for a guy like me it certainly was a bit daunting. I have read other posts regarding much more detailed issues and explanations, but you take them all as a problem that you can help solve and treat them all with urgency. I can't say enough about this forum resource!

You guys ROCK!

[itscali]

I did just see what Chip wrote and think I will take his suggestion as what I ended up doing really is a temporary fix. Knowing now what the issue actually is, and how to replace the part, should make this a very easy swap-out. Thanks again Chip for bringing that up.

[Jazz P Bass]

External Spaeker Jack

Personally, I would let it alone
You fixed it.

[Fragger]

I`m with Jazz P Bass but with that said, "that which does not kill us makes us stronger" should you decide to remove the amp from the comb.

On my Crate GFX65 combo I pulled two speaker wires off the terminals, removed or loosed 4 bolts on the top till I could slide the amp out and seperate it from the combo and set it on a folded towel on the kitchen table for inspection.

Hardest part of removal was pulling wires off speaker terminal `cause they have some kind of lip to hold them on.

[Jazz P Bass]

Let It Be

Yeah, and the wires pull off the terminal or you snap off the terminal board or......
Let it go!
Just my 2 pence worth.
Been there, done that.

[Enzo]

You bent it so it would work, that's good enough. In the trade we'd write that as "reformed contact blade."

[itscali]

You bent it so it would work, that's good enough. In the trade we'd write that as "reformed contact blade."

Enzo, I better like your lingo than mine on the proceedure. Mine sounds like I went in with a barbarian axe

[pecorporation]

I like that, "reformed contact blade"..may I use it?