16 ohm speaker instead of 8 ohm ?

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by 335guy, Feb 28, 2012.

  1. 335guy

    335guy Member

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    What's the downside of using a 16 ohm single speaker instead of an 8 ohm speaker in a DRRI ? Is it okay ? Volume loss ?
     
  2. GearHeadFred

    GearHeadFred Member

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    It creates a mismatch... Some of the side-effects of a mismatch are:

    - Decreased output (volume loss, as you say)
    - Change in tone
    - Additional stress on the output transformer
    - Additional stress on the output tubes

    It's a bit political (you'll get other opinions).. but it's most likely "OK" to do this because it's "only" a 2:1 mismatch, and in the safer direction (higher, not lower)

    Or it could burst into flames on the first note :sarcasm
     
  3. zenas

    zenas Member

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    I don't know if the trannys in the RIs are as good as the vintage Fenders.
    The old black and silver face amps sometimes ran for years mismatched.
     
  4. LarryN

    LarryN Member

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    It should be fine. You won't notice much loss. The transformer build is the same.
     
  5. chervokas

    chervokas Member

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    With that amp you'll probably be fine safety-wise but yeah loss of power transfer from amp to speaker so less volume, less headroom from the amp too. There will also be a change in the amp's frequency balance because you'll have changed the reflected impedance load on the amp's output stage.

    There is a danger from mismatching with a higher load from flyback voltages which could potentially damage an OT, output tubes, or other parts depending on the OT's insulation and other factors. The Deluxe Reverb, at leat the old BF ones, were notoriously tolerant of slightly mismatched loads in this regard though so you'll probably be fine (a lot of the potential danger in this regard depends on the turns ratio of the OT), but all-in a mismatched load is less than ideal.
     
  6. Tele Wacker

    Tele Wacker Member

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    It may be ok but if you have an 8 ohm speaker, why put a 16 ohm in the amp?
    Some amp experiments are ok but Leo put out a great product. Why change it? I know your amp is well after Leo but I'd leave the 8 ohm speaker in the amp.
     
  7. pdf64

    pdf64 Member

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    That's safer for solid state amps.
    Tube amps are more tolerant of a 'downwards' mismatch (ie 4 ohm cab on 8 ohm amp). That's the arrangement that the vast majority of classic Fenders appear to be designed to accomodate.
    Pete.
     
  8. smolder

    smolder Gold Supporting Member

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    I recall reading that some small 6v6 amps ( was thinking it was a sf deluxe NR) are designed with an OT secondary of 6.2 ohm, which put the 8 ohm speaker at a mismatch already, and on purpose. Can someone validate or in invalidate that? I can't find where I read it.
     
  9. 335guy

    335guy Member

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    Thanks for the words of wisdom guys. I thought I would hear less volume ( output ). I just wondered if I would harm anything.


    It does have an 8 ohm speaker in it now. It's just that I have another speaker that is very different in tone and 16 ohms and I wondered how it would sound in my DRRI. The 8 ohm speaker is an Eminence RW&B, and the 16 ohm speaker is a Celestion GM12 Greenback.

    Yeah, I know I can do that. I was just wondering if a 16 ohm load would hurt the amp.
     
  10. ptrickamp222

    ptrickamp222 Member

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  11. smolder

    smolder Gold Supporting Member

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