Jet City JCA 5212 doesn't seem loud enough. Please help!

[MR MARCUS]

Actually it isn't loud enough. I can stand right in front of the amp at full volume. It's kinda loud but for a 50 watt tube amp it should be really loud. I swapped out tubes. The tubes are biased at 35ma(they were at 9ma). I reflowed the solder on the preamp and power tubes, probed all resistors and checked for loose connections and could find nothing. Only thing that looked wrong was the effects loop return ground wire was disconnected and when I try to connect it to a random ground I either get silence or loud hum. I haven't checked any voltages yet and I can't find a schematic. I was just checking to see if any of you guys might have an idea.

 

[racerevlon]

Since the effects loop on those is serial I can see where that wire not being correctly connected would mess with your signal strength. Get with Jet City tech support or Brian from BFG (Briango2000) and one of them should be able to tell you where to reattach that wire.

Good luck!

 

[bravedude2]

buy 100 watt next time

 

[roberto1000]

Hi, i'm robert and i bought a jca5212rc a year ago. I really like its sound. I have played it just at home but last week I took it to a garaje to play with some friends and I notice it has a low volume for a 50w amp. My friends played with a 40w fender blues deluxe and a 50w fender hot rod. They have very much more volume than me. I have tried to search in the internet but you are the only one I have found with that problem. I would be very grateful if you could tell me how you repair it or any idea. Thanks a lot
Pd. I replace six months ago the power tubes with a pair of tad premium 6l6 gc

 

[midnightlaundry]

They have good sized transformers but no choke. 'Not sure about the efficiency of the JCA Eminence tho..

A 112 open back certainly won't match a 412 of Vintage 30's..

 

[Jimnastic]

Hi, I’m a bit late to the 5212 party but I picked one up and agree, it’s not loud. Looking through the schematics I THINK it’s because of the R16 resistor taking the signal down low enough to feed effects send for standard pedals (which seems reasonable), which is unlike its SLO based jca50h which outputs at roughly line level (and you don’t need to look far to find folk who are frustrated by this also!)
So, having had a quick play with a pot, if you up the value in R16 you get a SIGNIFICANT amount more signal going through to the reverb mix stage.

Did you ever resolve your issue? If not, have a look in that part of the schematic!

#im sure I’m supposed to say somewhere don’t open the amp up unless you know what you’re doing, some big voltages be thaaaaar#