Please help me with this noise, Fender DRRI

SoK66

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I did a writeup on the noise exorcism I had to do on my '20 '68 CDR.

 

Cheap Trills

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Scratch and dent usually means a demo or otherwise new amp that's been marked or has a minor cosmetic defect.

Yours is a 'refurb'. That's not a bad thing, BTW. You've scored a Celestion Redback - that's a $250 speaker. Most people wouldn't put one in a DR but if it's doing it for you that's great.

Your amp also has JJ power tubes - did you put those in? Were the originals Groove Tubes or Fender- branded? Tube rolling - OMG, should we start you down that rabbit hole? JJ 6V6s are considered the toughest current production power tubes for a DR which does run them hard

Manufacturers don't usually fit the 'best' tubes. They do a deal for bulk purchase of tubes that will get the amp sold and last through warranty.

There's tubes, and there's tubes. All 12AX7s are not created equal. JJ preamp tubes are not as revered as their power amp tubes. Except in Mesa Boogies which seem made for them. 'Marshall' branded tubes are made by Shuguang, a Chinese company. As are most Ruby and a few other brands. 'Tung Sol' and 'Mullard' tubes are holy grail brands resurrected for marketting purposes but are made in Russia. Many people will fit different tubes - you will hear terms like 'bloom', bright, dark, gainier, smooth, harsh etc. There NOS meaning 'new old stock' or brand new tubes in boxes from forty years ago. The general consensus and experience is the old production tubes are better sounding and last longer.

The fact you have a tube marked ECC83 indicates someone has been trying different tubes. ECC83 is the old Euro designation for a 12AX7. Not commonly used since tube factures thee shut down in the 80s. So that was probably an old tube. Might be a good one for V2. That's the first preamp tube of your reverb channel.

If that tube was in V6, the phase inverter position it could provide a volume boost because it has more gain. But it will also make your eqs more active and possibly increase noise floor and make reverb a bit more twanky. It is likely the source of your noise combined with dirty pins

I'd try cleaning the pins of all tubes - power off, unplugged.

If you prefer the sound with the 12AX7 in the phase inverter position, you will do absolutely no harm leaving it there. Ditto the Redback. Depending on what sort of music style you play it could work. Mostly the Redbacks are used in higher wattage Marshalls as they handle 150 watts. But there's no rule that says you can't use one in a Fender.
Thank you for all this useful information! The deoxit arrived in that mail and I'm planning on cleaning things thoroughly tonight
 

Cheap Trills

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got derailed with a certain virus running through my household, but got to it tonight. I sprayed deoxit on all the tube prongs and worked them in and out the sockets, and put in new tubes in the p1 and v1 locations, and.... it's still making the noise. So frustrated! I immediately started looking into digital amps, but then I watched some videos and realized it would take me forever to figure out how to configure them. I guess next stop is to have someone look at it that knows what they're doing?
 




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