jjscreeds

picked up a trace elliot brightbox from mike recently , works great with my 15" trace combo. Really friendly bloke and a pleasure to talk too, even got a great cup of coffee and checked over a fender p bass for me. Thanks for the tip with the clippers on the carpet too, I can now get that perfect trace style

just picked up this today, Its in a sage green metallic , I havnt seen many in this colour so i thought i would share it. [attachment=160836:DSC_0786#1.jpg][attachment=160837:DSC_0793.jpg]

This is what im learning to play bass with, I had the Ibanez sr300 with a tiny practice amp then joined this forum to buy the Warwick fortress. Feeling the need to do the Warwicks growl a bit more justice I got the Trace Elliot GP12SMX and now my neighbours hate me I had no idea how loud this was going to be . [attachment=159584:DSC_0780.jpg]

thanks for the diagrams icastle, just shows that even with almost zero knowledge of electronics, a bit of common sense and google can fix anything

parts arrived today, so got my tester and soldering iron out, changed tr22 and tr23 as tr22 have gone open circuit, changed tr1 because it only took 5 mins extra while it was out. Standby is now fixed fully functioning . tr1 didnt seem to need changing and made no difference to the high input gain required, but i can live with that as it may not be a real fault anyway.

ordered some , like you say they are cheap so why not

I have just had my gp12 smx amp apart for a different reason and checked this out as i had read your post, mine isn't connected to the speaker outputs at all, the high pass filter control on the back is only on the send and return and doesnt control anything on the speakers . Maybe someone had modified it for a specific reason.

they are j112 transistors, i just edited the above post with another idea, 1 more transistor is on the pcb and thats in the input gain circuit

Thanks for the diagrams, reading the output stage bit about a transistor between the output and ground that is switched on by sw3 (standby switch) and the drain is the same voltage as the source and shorts that out to ground for standby. Could that be why i cant switch to standby? and if so where is it on the diagram? because the standby switch does nothing but turn the led on, the amp functions as normal, maybe its not grounding the output. maybe tr22 and tr23 and tr1 have blown , they are all JFET transistors. tr22 and tr23 look like the ones that goes to ground for the standby and tr1 is in the input to input gain circuit, could all 3 of them have died and cause both the standby and low input gain problem? I had already fixed a broken power wire to the pcb board, they had two orange and a black wire, one of the orange ones was broke at the connector. Could a dodgy power supply from this break have caused all the FETS to die from a low voltage or something? My Googled knowledge of circuits can be a little dangerous and if there is anybody that can tell me if this could have happened, i would really appreciate it. thanks

well i got it all back together and its exactly the same as before. Is using the amp the way it is going to kill it completely, as i cant switch it to standby? Also it makes a screech thud when i turn it off, is that still related to the standby not working problem?

i probably should have said that i knew it wasnt the main tube, it looked like small versions. sorry

its not the valve, its a tiny uv lightbulb. I found the number for EMS on this site and just got off the phone. Man said that i can just remove it and it wont affect the amp so i am hoping that the other bits ive fixed have cured the problem. Its almost back together now, 30 mins and i will let you know if ive fixed it or not.

Hi everybody , Thought i might use my first post as a cry for help from the guru's here. I have a slightly not working GP12 SMX amp combo that i have in pieces in front of me. The problems are that the standby switch did nothing, still noise when off, even on max input gain with an active bass i could only just get the ok light to flicker, and a slight hum when on passive but silent when switched to active. Other than that it sounds great . As im not scared of taking things apart i have found a few problems, input jack joints was loose, broken wire to the main board ( think it was a power supply ) , loose speaker wire at the board and a smashed tiny tube valve ( Luna G II or IT on it) that was on the right hand side of the EQ board . I fixed the rest but would like to know what the valve type thing is and where i can get a replacement from? Please dont go too technical, i am no electrician . Thanks

bought a warwick fortress 1 from martyn. very easy to deal with and answered all my novice questions without laughing at me once. friendly bloke and was a pleasure to meet .