Archon 50 combo question about noise (low trrr... :) sound)

Discussion in 'Amplifiers' started by Gothearl, Jul 27, 2018.

  1. Gothearl

    Gothearl New Member

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    Hi all, this is my new/used amp. made on 12/15 bought of reverb.

    The sound is just awesome - both high gain and clean.

    I'm noticing constant low noise rattling trrrr.... sound ") on both channels. Putting amp into standby mode eliminates it. Is it preamp tubes?

    made on 12/15

    Also, one preamp tube missing the safety thingy - 3 of them standing at the top of the amp (where can I get one?)

    [​IMG]
     
  2. LSchefman

    LSchefman Hears Tones

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    You can get the tube covers at any parts store, like Allparts, though you might be able to get them from PRS Customer Service. However, they’re standard items.

    I’d suspect a bad preamp tube. Do you know how to check them? I won’t give you the song and dance if you’re experienced at tube stuff.
     
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  3. Gothearl

    Gothearl New Member

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    I don't know how to check them - going to google it. Ordered replacement, but would be nice to know how to check the wrong tube.
     
  4. LSchefman

    LSchefman Hears Tones

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    The trrrr sound you describe might be what’s called ‘motorboating’ and if so, it’s a preamp tube. But it might be something else, of course, there are no guarantees with this stuff.

    First, I always turn the amp off when changing a tube. Safety first!

    OK, unplug your guitar/pedalboard/dc loop. You want just the amp. Turn it on, let it warm up, and then switch it out of standby. Then turn up the volume a bit, not all the way up, just so you can hear the problem.

    The first thing I try is to tap very lightly on each preamp tube with a pencil or chopstick. The first tube near the input jack is the V1. Note that even if the V1 tube is good, you’ll hear the tapping in the speaker.

    But if it’s really loud, or really sensitive, it could be a bad tube. If it’s not the V1, move on to the next tube. In any case, tap each tube lightly, and see if they make any strange noises you can hear through the speaker. If you can hear ringing, or loud tapping, or anything unexpected, simply replace the tube.

    If tapping the tubes doesn’t tell you anything, then the next step is to swap each preamp tube - one at a time - with a known, good tube. Turn off the amp, replace the tube, then turn the amp back on. This is a process of elimination. Be patient, and replace each preamp tube with the known good one. If the problem isn’t solved, move on to the next tube.

    Also remember that more than one tube could go bad. Modern tubes aren’t as well-built as the old ones, and they tend to be more fragile. This is especially the case in combo amps, where the vibrations from a nearby speaker in the same enclosure vibrate the hell out of tubes. So you might find more than one bad tube. It happens.

    As an aside, I use NOS (“new old-stock”, or “unused”) preamp tubes from the 60s, 70s and 80s that tube dealers dig up, because they tend to sound better with less brittleness and ringing, and last longer. But even NOS can occasionally go bad, even though it happens less frequently. Then again, I’m a freak and maniac about tubes, so, take my advice with a grain of salt! ;)
     
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  5. Gothearl

    Gothearl New Member

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  6. Gothearl

    Gothearl New Member

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    Alright tubes did arrive today - after USPS sent them MA-NJ-TX-NJ-CT ;)

    and ... it didn't help - changed all 6 o_O



    should I look into Power Tubes now?
     
  7. dmatthews

    dmatthews Dave's not here...

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    Has the amp been plugged into any other electrical outlet than the one you're using now?
     
  8. Gothearl

    Gothearl New Member

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    Yes, I moved it around the house and tried Furman M-8x2. Still the same noise.

    I used to have Traynor YCV80 2x12 amp and that wasn't so noisy. Granted Archon sounds just stunning.

    Thank you guys for all your help. Going to look at what else can be done.

     
  9. LSchefman

    LSchefman Hears Tones

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    I’d give PRS customer service a call. They can help.
     
  10. vchizzle

    vchizzle Birdman.

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    Some amps can be noisy if the tube shields are not on. Also, the Archon can be noisy with pedals sitting on top of the amp. This sounds a little weird to me. Almost as if it’s something running on the same electrical circuit as the amp. I know you switched outlets but maybe something like a fan, dimmer switch, refrigerator fan, air conditioning unit...

    I’d probably replace the power tubes too since they’re 3 years old, just to rule it out. Les’ advice on contacting PRS customer service is a good idea.
     
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  11. Gothearl

    Gothearl New Member

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    solved

    alright, it's was internet via powerline. THIS thing solved it. CyberPower from homedepot
    ($40)

    Hope it will help someone else.

    [​IMG]


    Sounds great even with noise though I do need an overdrive pedal :)
     
  12. bodia

    bodia Authorities said.....best leave it.....unsolved

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    Glad to hear you got it sorted out!
     

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