| Author | Message | ||
     tim shearer (timmins) Username: timmins Registered: 06-2009 |
It was working fine before I left for the show. At soundcheck, everything was powered up as normal, but zero output. Things I tried: - Checking the standby switch was off! - Valves all glowing healthily - Tried all inputs on both channels, hi and lo power setting. The behavior is as if the amp is stuck in standby. Any suggestions of what to check? The amp is a little frustrating, it's in spotless condition, but gets through a set of valves every 10 months and just isn't dependable. Disappointing because my old 65RP served me for nearly ten years, and didn't fail me once! Thanks, Tim | ||
| Mike Kaus (mm210) Username: mm210 Registered: 05-2006 |
Maybe it IS stuck in standby. Warm up amp, then watch the tubes AS you turn on the standby. Does tubes flair up for a second? If not, maybe the HV is not GETTING to the tubes. The heaters run obviously, without the standby so maybe the switch is junk OR the HV side is out. Just need to investigate a little further. By the way, does this have a 12ax7 or is it SS driven? | ||
| tim shearer (timmins) Username: timmins Registered: 06-2009 |
Thanks for the reply Mike, the amp is at the practice space, but I will try your suggestions. It's the 12ax7 phase inverter model. I didn't think to check that tube... | ||
| Mike Kaus (mm210) Username: mm210 Registered: 05-2006 |
That goes south, you also get nothing. | ||
| Lars Verholt (lmv) Username: lmv Registered: 11-2009 |
Is this by chance an export model? Some of these have fuses in the HV circuit. Cheers, Lars Verholt | ||
| tim shearer (timmins) Username: timmins Registered: 06-2009 |
Not an export model, but than ks for the suggestion. I will check into it this weekend! | ||
| tim shearer (timmins) Username: timmins Registered: 06-2009 |
Sooo... I checked the suggestions above. The 12ax7 tube is glowing happily. When I switch it out of standby, all four EL34s flair up a little, with a blue tinge that isn't there in standby. Doesn't glow as bright in low power mode, as I guess you'd expect. Still, he amp is dead silent. As I said before, I've tried all inputs, both channels. Any other suggestions welcome! Thanks, Tim | ||
| Mike Kaus (mm210) Username: mm210 Registered: 05-2006 |
Now I would start by checking the cord from the amp to the speakers and the speakers themselves for continuity. Then let us know. Simple things first. Mike | ||
| Brian M. Watson (mrroundel) Username: mrroundel Registered: 06-2007 |
I know that I'm late to this one, but I wanted to add to Mike's suggestion on the chances of the 12AX7 going out. I know that this is correct because after doing the cap job on my 210HD 130 I forgot to put the PI tube in. Everything started up nicely, with tubes glowing a healthy orange, but I got no sound after switching the standby switch. I was worried for 30 seconds until I realized what I'd done. Doh! Don't have me replace Homer at the nuclear plant. As soon as I put the 12AX7 in, she worked like a charm. Sweet sounding amp, for sure. | ||
| Christophe (vignau) Username: vignau Registered: 06-2011 |
I had the same pb with my 210HD130 SS driver, it took me long time to finaly discover it was the IC spliter (0.30 €) that was in short after running 30 min with new caps/tubes. Check if you have the +16-16 V on preamp, could be the zeners as well, they are too low wattage. |