Eros is humming
- Thread starter Why1504
- Start date
I spoke to soon. For the first 1-2 hours this thing sounds fantastic. And then periodically I get a horrible scratchy popping noise (its like you drug your finger over the stylus on your cartridge at a medium high volume). It will last less than 15 seconds then it will stop. Sounds beautiful for 4-15 min then it happens again. It is so violent I was worried it was going to damage the speaker. It is only occurring on the B side. Right now I am in the 4th iteration of good sound.
If I tap on the chassis nothing. If I wiggle the Phono input into the Eros when it occurs it makes it much worse. If I wiggle the input when it isn't occurring no noise.
I am stumped.
Edit:
Re-wet everything again this morning.... Man it sounds good. I hope the gremlin is gone.
Edit 2:
This is promising, I swear it is sounding better and better!!
If I tap on the chassis nothing. If I wiggle the Phono input into the Eros when it occurs it makes it much worse. If I wiggle the input when it isn't occurring no noise.
I am stumped.
Edit:
Re-wet everything again this morning.... Man it sounds good. I hope the gremlin is gone.
Edit 2:
This is promising, I swear it is sounding better and better!!
After multiple de-soldering/re-soldering of all of the connections on the "B" side the problem persist. I no longer believe the problem is my poor soldering skills.
I find that 2 of the socket pins from below are loose even with the tube plugged into it. When I push on the offending tube the noise occurs. Could this be a dirty / bad socket or tube? please advise.
I find that 2 of the socket pins from below are loose even with the tube plugged into it. When I push on the offending tube the noise occurs. Could this be a dirty / bad socket or tube? please advise.
The Static on the B channel is constant now. Channel A is clean. Voltages are within spec.
I checked the tube pins, They were black. I got some DeoxIT contact cleaner. I polished the pins and cleaned them and the sockets with the cleaner and some 800 grit sandpaper. Zero Effect. Swapped tubes, no change.
HELP!!
I checked the tube pins, They were black. I got some DeoxIT contact cleaner. I polished the pins and cleaned them and the sockets with the cleaner and some 800 grit sandpaper. Zero Effect. Swapped tubes, no change.
HELP!!
Doc B. said:
Turned it on, no real change. Waited maybe 20 seconds, then the two towards the "A" end flash on and off. a few seconds past and the two LED's toward the "B" end got bright then went dim, then back to "normal"
The voltages are changing very rapidly and violently.
One possibility is that there has been some damage to one of the carbon comp resistors that connect to the grid terminals of the EF86 and the 6922, and maybe also the one that connects to the plate of the 6922. Try gently prodding at those with a chopstick with the preamp on, and see if you can make the fluctuation happen as you prod them. The leads on the carbon comps can develop a bad contact where they are inserted in the end of the resistor body if they get a little too hot when being installed and soldered.
Doc B. said:
I did as requested. I was unsuccessful in getting the LED's to blink or dim. The voltage spikes now seem to only be bouncing between 140 and 160.
So, I re-installed the Eros back into the 2 channel system. The "B" channel is producing music but it is way over shadowed by the noise. Again I was not able to get the LED's to blink or dim, nor was I able to cause the noise to increase, or decrease when pushing on everything (focused on the Resistors at first). Tapping on the plate also had zero effect.
I expect when I started I had several bad joints which I believe I have now repaired. The noise is popping, scratching, loud even at low volume and very violent.
Another possibility is the 6922 is making the noise. You mentioned wiggling the tubes generated the problem at one point. Not sure if that is the case now. Does wiggling the 6922 create the noise? Even if it doesn't make noise when moved it could be that the tube is misbehaving. Of course the best way to test is to try a different 6922.
It's not really a guitar amp tube so I kind of doubt they would carry them. We can send one to you. It kind of sounds like one pin sleeve in the socket might have been stretched and is making intermittent contact. You might try taking a very thin piece of stiff wire or a really tiny jewelers screwdriver and see if you can fit it between the ceramic holes and the metal sleeves and ever so slightly unstretch the metal sleeves in the tube socket.
pvannest
Member
I agree with what Doc just stated. I had a similar issue with mine when I first completed my Eros. I was going crazy trying to track the problem down. Then one day I had to move my system around and found that one of my interconnects had gone bad between the Eros and my preamp. Sometimes, it is hard to see the forest for the trees.
