Guitar amp problem - advice needed

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Sorry if this is a bit of a strange request but my guitar amp is not working and I would really appreciate some help with it. It a laney 100w TF300, turns on ok but has no sound coming out of it. I've tried different guitars and leads. Thought it could be the speaker but still makes a "pop" sound when turned on/off. I'm wary of taking it into a shop and paying someone to fix if its something basic I could do myself as I'm usually pretty good with electronics. It last worked a few months ago with my Bass which makes me think I could have blown it.

I'm sorry to hear about your amp and wish I knew enough to help you out. I can tell you that playing bass through it didn't blow it. At worst, you could blow a guitar amp speaker with a bass. If that was the case, you'd hear sound, but it would sound bad.

Good luck.

I have the same amp at home, is the speaker plugged in at the back, and it the input jack tightened up?
EDIT: Those amps are really bad for the input jack being dodgy. Are all 3 channels silent?

Sounds like your line in is blown somewhere along the way. Is it solid state or tube?

It's a so-called "Tube Fusion" amp, it's solid state with a single 12AX7 in the preamp. Do the gain channels still make heaps of hiss when their drive and masters are turned up?

Thanks everyone for the replies. Yeah its a "tube fusion" amp. I've just tightened the input jack. There's now some sound coming out of all three channels but not as much are there sound be. The blue wire going into the back of the speaker was loose as well.

I'd want to have the thing checked out professionally, because if the lead to the speaker was loose, you were running the power amp w/o a load, or an infinate load which will kill a transistor amp.

I don't know if you can afford it or not, but I would scour Ebay for an old small tube amp of some sort. Old tube PA amps go for low prices, and they can be converted for guitar usage relatively easily and a lot of times they have old tubes in them as well, which are usually much better than what is currently produced. -- It's usually just a matter of installing a 1/4" tipring jack.

You can actually get tubes (the Russians still make them, for one), if there's an amplification problem. I think the tube is actually there to supply 'tube harmonics', to get the 'analog' sound.

Note- nothing against tube amps, I owned one for decades; but there's the transformer, which is a great, hunking, block of iron (not actually...) that tends to weigh a ton, and throws the balance off when lifting. It will have an effect on your shipping of an amp should you get one that way.

Pawn shops, music stores, Craig's list, etc., might be a better option (if you're in the US)

Does sound like an amplification problem with the Line in. I'm no electrician, but that's where they'd start...

Current production tubes are nowhere as robust as tubes made in the past. A lot of the Russian stuff also sounds horrible due to the fact that their tubes aren't quite the same as former western tubes. Furthermore, Russian tubes were primarily manufactured for the Military not for consumer applications like HiFi so they never really cared about making a good sounding tube.

That being said, yeah tube amps not only have a PSU transformer like nearly all other amps, they also have an output transformer as well which brings the high tension high voltage signal back down to voltages and impedences that can be used with speakers. depending on the size of the amp you have this can add either a little weight or a lot of weight.

As far as throwing the physical balance of the amp off, this would be entirely dependant on the physical layout of the amp. A lot of manufacturers distribute the weight by placing a transformer on wither end of the amp chassis.

Ugh...well, at least its just a matter of breaking out the soldering gun. I never had contacts break in an amp pickup but I used to have that problem all the time with the output jack of my guitar - seemed to break its welds at least once every few months.

Check the jack on the guitar as well. You might want to check the contacts are all good on the inside of all the jacks (that means opening it up). The problem is not with the tube.

Ok, I'll admit, I'm prejudiced; I schlepped a Peavy Centurion around for about 20 years. The transformer was at the end, so when you picked it up by the handle, the whole thing sloped...

Didn't know about the quality problem with the Russian tubes; but then in all the time I had tube amps, I replaced maybe a single 6L6, (or was it one of the E34s?)

yeah, here's a quick buy noisy way to check the connection is your guitar or the amp. Take a known good signal cable and connect it to the amp, and then turn it up (enough to tell is all). Place your thumb over both contacts at the end. You should get a loud hum for whatever amount of time you do that. If the volume is right, check the electronics on your guitar (or better yet, have someone do it).

If I remember correctly, Peavey's older amps used the same transformer layout as Fender and Marshall, which had the power supply transformer (The bigger of the two transformers) on one end of the chassis, and the output transformer on slightly off center of the middle of the chassis, not unlike this amp that I own.

yeah, you pick it up, and it pitches forward, or backward. I finally bought some casters, borrowed an electric drill, and drove it for the next 19 years...