1st tube amp - problems galore - need advice

S

SculptureOfSound

New member
Hi all,

Sadly my 1st tube amp purchase is not going so smoothly. Starting to wonder if I should have gone the easy route and got a Kemper instead.

Anyhow, I bought a Framus Dragon off of Reverb. It came in with one broken power tube. Working with the seller now on a shipping claim.

Thought I just had to look at this head for the next week or two while this resolves but then remembered I have a Carvin TS100 tube power amp that I used with my old pedal board that was fitted with EL34s. I pulled those tubes and put them in the Framus but the gain is *maybe* 50% of what it should be. Sounds more like a 70s Marshall tone rather than the balls to the wall hotrodded JCM800 tone the crunch channel should have, or the SLO-esque tone the lead channel should have. Seriously the gain is maybe 50% of what it should be.

The tubes that were sent were Ruby EL34 BSTR and the tubes I swapped in from the Carvin are Electro Harmonix EL34 03 05. Could power tubes make SUCH a drastic difference in gain? I thought it was preamp tubes primarily responsible for the gain so I swapped them around a few times in case one was bad but noticed no change in tone. I don't have any spare 12AX7s to test - how likely is this the problem?

So assuming that power tubes can't lead to a gain reduction of 50% or more (even if the bias is off, which it probably is with the new tubes), then something is wrong with the head. Any idea what it could be or what I could try? I tried different cables to no effect, tried a different guitar. Not much more I can think to do with the gear I have.

Also, not sure how I should go about this with the seller. We're in the middle of a shipping insurance claim on the original busted power tube - need a quad matched set for replacement. But if there is other damage was caused by the shipping that is leading to this lack of gain (feels like a whole gain stage or two are missing?!) then what do I do? Ship it back to him before resolving the original power tube issue and let him make any additional claims on damage? Adjust the claim to cover the cost of any additional repairs?

Any advice is appreciated. Just wanted to move from digital to a tube amp, didn't think the transition would be so difficult! lol
 
Did you bias it? Sounds like maybe a bad preamp too, or it took a hit in transit. I'd take it to a tech, or arrange a return.

But, my first course of action would be a COMPLETE douching. Pull the chassis and tubes, clean the sockets, retube with brand new tubes, and bias it properly.
 
If you're going to be a tube amp owner you're probably going to want to have some spare tubes. Most of the time, a problem with tone, output, or noise is tube-related. Everyone is different, but when I buy a new amp I often figure in the cost of retubing it to, just depending on how old the tubes are, how it sounds, etc.

If you've just replaced the power tubes but haven't biased it then you're already in a situation that's sub-optimal. Bias it and then see how it sounds. Then I'd rotate in new preamp tubes one at a time.
 
Lack of gain in that type of amp (High gain preamp) is most likely a preamp tube...maybe the input jack and pots need a cleaning (spray with deoxit) but I'd bet you have a weak pre tube or 2. Sometimes the FX loop jacks might need a cleaning too, which can affect tone (Silver Jubilee) but probably a 12ax7 or 2 need replacing.
 
The guys above are all correct. Get her sockets and loop all cleaned up, biased properly then work the pre amp tubes.
 
I preface this comment by admitting I’ve never owned a Framus - but - some channel switching amps will ‘default‘ to a single channel when the footswitch is disconnected. This design may require the switch to be plugged in to allow you to access the additional gain stages. By way of example only, Mesa Mark series had a push-pull pots on the gain controls that would allow you to access the higher gain lead channel when the footswitch was disconnected, but they were pretty clearly labeled ‘pull-lead’. Just a thought.
 
OK - the Dragon has dedicated push-button switches on the face of the amp to select the channels - along with a footswitch. It looks like V2 & V3 are your lead gain stages and 5 is the phase inverter, any of which could be the culprit for a lead channel with only half the gain. Known good 12AX7s are relatively cheap. I’d swap the full compliment at once. If more than one preamp tube is faulty, swapping only 1 at a time would not resolve the missing gain stage.

https://m.jam.ua/files/files/WW_DRAGON_EN_MANUAL.pdf
 
Can't really add anything that hasnt been posted. When I buy an amp I fully intend on replacing the tubes, period.

You cannot just pop in another set of power tubes, the amp must be biased correctly to the tubes.

Preamp tubes, clean sockets, fuses. Yeah, there can be a lot of maintenance but as someone who has owned both the Kemper and the AX8, both great tools in their own right. Nothing can replace tube power, not yet anyway. It is worth learning an amp. Just like learning your guitar, guns, car, motorcycle, computer or whatever it is that you do.
 
scottosan said:
Let’s revisit this in a decade
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Agreed. Just like all the crap gear from the '80's did, I think the modeling gear will fade away eventually. I'm not knocking modeling technology. It's just not for me.

A power tube will probably not cause that much of a loss of gain. Like others said, re-bias the amp. My guess is that it is a preamp tube issue. I had this same issue with a Laney AOR 100 back in 1987. Tube amps do have an expense to them, but it's so worth it when you have a good one. I've bought amps for dirt cheap because guys thought the amp sounded like crap and all it really needed was a couple of hundred dollars worth of work done
 
flatheads_4ever said:
Agreed. Just like all the crap gear from the '80's did, I think the modeling gear will fade away eventually. I'm not knocking modeling technology. It's just not for me.

A power tube will probably not cause that much of a loss of gain. Like others said, re-bias the amp. My guess is that it is a preamp tube issue. I had this same issue with a Laney AOR 100 back in 1987. Tube amps do have an expense to them, but it's so worth it when you have a good one. I've bought amps for dirt cheap because guys thought the amp sounded like crap and all it really needed was a couple of hundred dollars worth of work done
Click to expand...
Modeling is a new chip or firmware upgrade away from being somewhat obsolete. On a tube amp, any part can be replaced. As for these modelers, they are packed with proprietary hardware and software.
 
maddnotez said:
You cannot just pop in another set of power tubes, the amp must be biased correctly to the tubes.
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I've done it numerous times over the years with no issues lol. Of course it's definitely better to bias if possible.


Either way, if a Framus Dragon has barely any gain it likely has nothing to do with the power tubes
 
Devin said:
I've done it numerous times over the years with no issues lol. Of course it's definitely better to bias if possible.


Either way, if a Framus Dragon has barely any gain it likely has nothing to do with the power tubes
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Depends on the amp and tubes. Typically, EL34's need biasing and not so with 6L6"s. I've swapped EL34's in and out of old Marshall's without issues before.

Ed
 
Thanks for all the responses so far. I definitely agree it's worth learning tube amps and their maintenance and I do intend to but am not sure I can be doing all of the above recommended while this may still need to be returned. However, if it is possibly/probably a preamp tube issue then I will buy a set of 12AX7s and try that out. Worst case scenario if nothing is fixed then I have a set of spares.

It feels like gain is maybe 50-60% of what it should be. Besides lacking gain the "character" of the tone is all wrong. The bass is super flabby no matter what I do. I know the Dragon is not as tight as the Cobra or a VHT UL or whatever but, well, I guess the best way I can describe it is that it makes my bridge pups sound like neck pups and neck pups sound like total mud. On my Carvin it has active electronics w/ a bass and treble knob, and even with the bass completely down and treble cranked the low end is super loose. Normally this setting on my guitar creates a thin almost shrill tone on any other amp.

Would biasing possibly have this effect? Maybe the fact that my speaker cab is Celestion G12 Centurys? (not Century Vintages). I can't imagine either of these would have such a drastic effect but maybe?

I put my Boss GT-3 infront of the amp and tried a few different OD pedal settings and that helped somewhat with the gain but it still all felt so loose and flabby and fizzy.
 
99% preamp tube is the issue. It's not uncommon.

I bought a jp2c brand new with bad preamp tube. Same exact symptom.
 
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