| Author | Message | ||
     Rolandgp16 |
I bought a HD 130 HD head amp brand new back in 1979 or 80 and still own it today. I have replaced the tubes once and I can honestly say this amp is superior, reliable and in excellent condition. I noticed over the years especially when the bright switch is on there is hum/noise...not bad but its there. I run the amp thru 2 e120 jbls that I bought in 1980 and they are amazing speakers. Steve you have a good website here. Very informative. Im think about replacing the 4 el34's with some JJ tubes as well as the PI tube. Any suggestions about the noise/hum that I have. I always run the reverb on and I notice when I turn it off the noise diminishes but it is still there | ||
| michael kaus |
25 yr old tubes amps are due to have the caps changed. The electrolytics ones are the ones that need changing. Make sure that you change ALL the elctrolytics, not just the main filter caps. The bias supply cap is VERY important. There are also a couple of small ones on the main circuit board as well as in your tube driver version, on the driver board. That's where I would start with hum problems. Mike |