New 65 PRRI - feedback with high reverb

Discussion in 'Glowing Bottle Tube Amp Forum' started by bglaze, Feb 24, 2020.

  1. bglaze

    bglaze Tele-Holic

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    I bought a new 65 PRRI today.

    It was the floor model, but that didn't bother me, as it's still under warranty, and the shop is a small boutique shop that doesn't get Guitar Center-like traffic. Also, since it's a Fender Princeton, I doubted highly that any metal heads cranked this thing to demo it.

    Anyway, the amp sounds amazing. But, if I have the volume above 7, and the reverb above 6 or so (which honestly, I would likely never do in a real playing situation), the reverb begins to give feedback. As the feedback was growing, I made the mistake of turning the reverb UP, and it grew instantly into a squeal that killed my (and my dog's) ears.

    Anyway, should I be getting any feedback at all with a new 65 Princeton Reverb Reissue?

    This is my first tube amp, so I am not sure what to expect.

    Overall, the amp is so good, that I really don't want to return it. Or, maybe there is another solution? Maybe it can be easily remedied some other way?

    Any advice would be great.

    Thanks so much!
     
  2. Peegoo

    Peegoo Tele-Afflicted

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    Probably a microphonic reverb tube.
     
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  3. corliss1

    corliss1 Friend of Leo's Platinum Supporter

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    Yup - either a funky tube or maybe a cable issue is the most likely answer.
     
  4. Dacious

    Dacious Poster Extraordinaire

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    What are you doing which may cause this - sitting right in front with your guitar? Using lots of overdrive. What's your guitar and pedals if any, and where are you sitting the controls. Most people would never run PR reverb on 7, be all swampy and too syruppy.
     
  5. bglaze

    bglaze Tele-Holic

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    The first time I heard it, I was using a single pedal - Ibanez Tube Screamer TS-808.

    Also, yes I was sitting in front of the amp with my guitar, about 3 - 4 feet away.

    I then noticed it one other time, without the pedal, but volume was at 7 and reverb was about 6 (like in my OP).

    And... I agree with you. I would never play it this way. It is just a new amp, and I am testing its tone with various settings (even bad ones).

    So, this may not be an issue with regular tone settings. My typical settings, as far as I can tell right now, would be Treble 4, Bass 7, Reverb 4, Speed 3, Intensity 3.

    With those settings, I am not getting feedback.
     
  6. Dacious

    Dacious Poster Extraordinaire

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    Well, sitting facing any amp 3-4 feet away will make an amp squeal. Esp through a Tube Screamer which boosts - treble. At that distance you also won't hear what it really sounds like. You need to be a good dozen feet away to get a balanced hearing. Otherwise you are only hearing treble freqs and losing bass.

    With treble set 4 and bass 7 if your guitar is dimed you're at risk of fart outs. Esp with volume 6+.

    The speaker will sound spiky and harsh for a few hours - they play in to become smoother over a week or so.
     
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  7. muchxs

    muchxs Doctor of Teleocity

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    The tank is stuffed right under the speaker. There is more gain than necessary on the reverb recovery, more gain than you'd use. Cue litter of hungry piglets...

    Dynamat on the tank will calm it right down.

    I've set up any number of Princeton Reverbs to play clean almost wide open and cranked Trainwreck dirty louder than any stock Princeton could hope to be on the other end. That's clean 'n' tight. I haven't applied my recently developed Evolution II tricks to a Princeton Reverb yet.
     
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  8. schmee

    schmee Poster Extraordinaire Silver Supporter

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    It's not uncommon even on vintage Fenders. Can it be feedback free? Yes, if all the planets align right, or you have everything in the reverb path tweaked to perfection....
     
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  9. bglaze

    bglaze Tele-Holic

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    Thank you so much! This is great advice. Also, I LOLed at:
     
  10. bglaze

    bglaze Tele-Holic

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    Thank you! I was just wanting to make sure that it was normal and that this floor model hadn't been used so much that something had gone out of spec.

    This is my first real tube amp, so I'm very ignorant. But I'm also very excited to learn, as this is the best sounding piece of equipment that I've possibly ever owned. Super fun!
     
  11. schmee

    schmee Poster Extraordinaire Silver Supporter

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    I would definitely try a different reverb driver tube for improvement, it probably came with cheap tubes anyway and one of the biggest problems with 9 pin tubes is microphonics, even (especially?) with vintage tubes!
     
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  12. fasteddie42

    fasteddie42 Tele-Holic

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    Sounds like you're just using goofy settings.

    Turn the reverb down lol.
     
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  13. bglaze

    bglaze Tele-Holic

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    I believe you are correct =)
     
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