Hoffman Amplifiers Tube Amplifier Forum

Other Stuff => Effects => Topic started by: AScott on July 24, 2018, 01:53:23 pm

Title: 6G15 Troubleshooting
Post by: AScott on July 24, 2018, 01:53:23 pm
I put together a Hoffman G615 using the turret board and it sounds great. I have been taking it out gigging and last night late in the last set,  (I would say we have been playing about 4 hours), it started cutting out. It would not go dead but the total volume would just suddenly cut in half. The head was sitting on the stage floor not getting bounced around. I am not sure what would cause this and I haven't started trouble shooting it yet.

So does anyone have any opinions on what could be likely cause of this problem is?
Title: Re: 6G15 Troubleshooting
Post by: pompeiisneaks on July 24, 2018, 04:57:16 pm
Intermittent sound often is one of two things:  1. tubes starting to go (since this is a new build less likely) 2. connections that are dry soldered, when heating up, start causing shorts.  You may want to look for grey looking solder joints.  If nothing specific seems obvious, power it up outside the cabinet, and use a wooden chopstick to probe every connection, capacitor, resistor, etc and see if something makes noise etc.

~Phil
Title: Re: 6G15 Troubleshooting
Post by: AScott on July 25, 2018, 09:08:59 pm
Thanks Phil, It ended up being the V1. I did an inspection of the solder joints, focusing on the tube sockets, and everything looked okay. Since I had a supply of tubes I just swapped out the 12AT7 and it fixed it. I went ahead and replaced V2 and the 6V6 while I had the back off.  Love the reverb.

Keep on rocking ....