External speaker compatible with Ampeg RB-210

Discussion in 'Amps and Cabs [BG]' started by rkm1993, Nov 30, 2021.

  1. rkm1993


    Nov 30, 2021
    I am not experienced in combo amp and external speakers as far as how compatibility works. For example do I need an external speaker with a higher wattage than my combo amp?

    Would I be able to hook up an Ampeg Portaflex 115 - 400w to my RB 210 - 500w?
  2. The 500 watts will be shared by the external cabinet and the internal speakers. You’ll be fine wattage wise. How many ohms the external cabinet is listed at is a more important consideration.
  3. rkm1993


    Nov 30, 2021
    So I was looking into the svt210 micro cab also and the specs state a nominal impedance of 8 ohms

    how does that work with the rocket bass specs of:
    500 Watts RMS @ 4 ohms 5% THD+N (with external speaker)
    250 Watts RMS @ 8 ohms 2% THD+N
  4. abarson


    Nov 6, 2003
    Santa Cruz
    The RB-210 has two 16 ohms internal speakers connected in parallel, resulting in an 8 ohms load. The amp
    delivers 250 watts when only the internal speakers are used.

    You can add an external cabinet of 8 ohms so the total speaker load presented to the amp will be the minimum of 4 ohms. Do not go lower than the minimum! The amp will deliver 500 watts to the total 4 ohms load it sees.

    The SVT 210 cabinet contains two 4 ohms speakers connected in series, resulting in an 8 ohms load. The speakers in this cabinet are rated for about 100 watts each. If you used it with the combo, each of the 4 speakers would be displacing 125 watts, or 1/4 of the total 500 watts. The SVT 210 speakers might be able to sustain this, but I'd feel more comfortable with a more capable cabinet.

    It's too bad Ampeg hasn't introduced any RB series cabinets to match the aesthetics, too.
    57pbass likes this.
  5. Analogeezer


    Jul 29, 2021
    yeah that is interesting given Fender does this (offers a lightweight, Class D combo with the option for an external cabinet to get the full power from the amp section).

  6. growler571


    Sep 19, 2007
    What about the a peg port a flex cabs. They pretty much match and I think among intends on people using them as extension cabs to the TV combos. If I hot the a peg rub 210 combo I would also get an alley of 115lf cab or whatever the ported pf115 cab is called with no horn in it to get the real deep fat lows and the full 500 watts.
  7. mbell75


    May 23, 2016
    Where are you playing you need more than the 210? That’s an awfully big stage for a large crowd. At that point, you should have a head with a 4x10 cab.