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Topic: 4 ohm load in a Fender Deluxe Reverb amp? |
Dave O'Brien
From:
Florida and New Jersey
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Posted 7 Jun 2014 5:56 pm |
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What are the pro's and con's of long term 4 ohm load on a silver face DR? either 8 ohm extension cab or a 4 ohm speaker installed (like an EPS-12C?)
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Dave O'Brien
Emmons D-10, CMI D-10, Fender Deluxe Reverb, PV 112, Fender Pro Reverb
www.myspace.com/daveobrienband |
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Stephen Cowell
From:
Round Rock, Texas, USA
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Posted 8 Jun 2014 12:39 am
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Accelerated final tube wear. Fenders are normally OK for a one-step mismatch in impedance... unless you're really honkin' on it, you should be OK. Two steps is a no-no.
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New FB Page: Lap Steel Licks And Stuff: https://www.facebook.com/groups/195394851800329 |
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mike nolan
From:
Forest Hills, NY USA
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Posted 8 Jun 2014 9:36 am
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| As Stephen says, OK 1 step either way. I know that you can't get an 8 ohm EPS 12-C, however, you can get a Telonics 12" at 8 ohm. I put one of those in a SFDR, along with a pair of JJ 6V6S power tubes. After fiddling with the bias and a couple of preamp and PI tubes, it makes a nice louder, cleaner DR. It is great for low to medium volume gigs... and bigger if the amps are miced. |
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Tom Wolverton
From:
Carpinteria, CA
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Posted 8 Jun 2014 7:50 pm
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I've got a Telonics 12" neo, 8-ohm in my old BFDR. Sounds great.
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To write with a broken pencil is pointless. |
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Jim Sliff
From:
Lawndale California, USA
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Posted 10 Jun 2014 3:20 pm
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You can also run many 6L6's in DR's with the right bias setting. There's plenty of info on the web about it.
Please also note that the 100% impedance mismatch being OK applies to most *Fender* BF and SF amps - but NOT many others. Marshalls, for instance, are very picky about impedance and many are equipped with an impedance selector switch.
Also - a mismatch down (a 4 own speaker in an amp looking for 8 ohms) is far safer than a mismatch *up* *1 16 ohm speaker in an amp looking for 8 ohms).
In the first case you will suffer from a small amount of early tube wear, but nothing significant. But with too high an impedance, many amps will encounter a phenomenon known as "flyback" where current is bounced back, primarily to the output transformer - a very bad thing.
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No chops, but great tone
1930's/40's Rickenbacher/Rickenbacker 6&8 string lap steels
1921 Weissenborn Style 2; Hilo&Schireson hollownecks
Appalachian, Regal & Dobro squarenecks
1959 Fender 400 9+2 B6;1960's Fender 800 3+3+2; 1948 Fender Dual-8 Professional |
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mike nolan
From:
Forest Hills, NY USA
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Posted 10 Jun 2014 6:12 pm
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The JJ 6v6s can handle a lot of voltage, they are somewhere in between a 6L6 and a 6V6 in that respect.
With the 6L6 tubes, you might want to go with a solid state rectifier... Also with 6L6 tubes, the DR OT is running closer to 4 Ohm.... so the 4 Ohm speaker might be a better match. |
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Carl Mesrobian
From:
Salem, Massachusetts, USA
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Posted 13 Jun 2014 6:25 pm
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Load resistor??
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--carl
"The better it gets, the fewer of us know it." Ray Brown |
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Dave O'Brien
From:
Florida and New Jersey
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Posted 14 Jun 2014 4:09 am 4 ohm
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Thanks guys...I'm keeping the original Utah 8 ohm.
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Dave O'Brien
Emmons D-10, CMI D-10, Fender Deluxe Reverb, PV 112, Fender Pro Reverb
www.myspace.com/daveobrienband |
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