Acme B1 as mid/high cab when bi-amping?

Discussion in 'Amps and Cabs [BG]' started by jock, Jan 24, 2004.

  1. jock


    Jun 7, 2000
    Stockholm, Sweden
    Is this a bad idea?
    Im going to build a sub 12" based on the Eminence Omega-12pro (700W RMS) speaker and need a cab for the highs and mids in my small bi-amp rig.
    I thought the B1 would be good as its flat and true sounding. And if the cab is only getting frequencies over say 100(?)Hz it would probably be loud enough, right?

    Is it a good idea?
  2. In SBB4, the Omega Pro 12 is good for 222 watts before it exceeds Xmax at 0.1189". Mechanical damage is at 0.8200".

    You can expect about 115 SPL at 90 Hz, 222 watts, not considering power compression. Therefore, you want a High unit that is capable of this. On paper, the Acme B-1 is good for 112 SPL at full rated power. Exceeding Xmax with the B1 won't be a problem, because it will be handling only the highs, where Xmax is not an issue.

    Think ahead as to how you are going to wire your biamp rig. You will want to use the B-1 standalone full range for very small venues. If you are running two cables, one from each side of the stereo power amp, that is fine. However, if you are planning on using Speakon cables (I do), with Pair #1 as the Lows, and Pair #2 as the Highs, you will have to wire the B1 cabinet for Speakon Pair #2 to be the Highs. This poses a problem.
  3. jock


    Jun 7, 2000
    Stockholm, Sweden
    Thats a little to tecnical for me I guess.:meh:
    Are you saying the Omega is a bad choice?
    Wont the Acme be loud enough?
    Do you think it could work with a stereo poweramp and a preamp with crossover? :confused:
  4. Petebass


    Dec 22, 2002
    QLD Australia
    Actually compared to some other 12's, the Omega Pro 12 isn't too bad.

    What he's saying is that while the Omega Pro 12 is a 700 watt speaker, the specs indicate that it is likely to start distorting when fed 220 watts. The adhesives etc may be good for 700 wats but the speaker itself moves too far at that power input to produce clean sound.

    So assuming you are running 220 watts, into the 12, the maths suggests that it produces 115dB maximum volume.

    So whatever speaker you decide to use as a mid-high has to be able to make 115dB worth of noise as well or it won't be heard. The B1 may not be able to match the 12 for volume.

    A B2 might but....I wouldn't use an Acme for Bi-amping. They're a full range cabinet. Acme actually recomend that you don't bi-amp their speakers simply because there's no need to.

    Can I ask why you're happy to build one of the two cabs? I'd be inclined to either buy 2 cabs, or build 2 cabs that are designed to work well together.
  5. jock


    Jun 7, 2000
    Stockholm, Sweden
    Thank. Now I get it.:D

    I was gonna build because its cheaper here in Sweden. And I think that the highs and mids is where the color of the sound is. Thats why I wanted a good cab with tweeter crossover etc cause I dont think I will be able to build that with a good result. The sub on the other hand is "just" a driver in a tuned box.
  6. Suburban


    Jan 15, 2001
    lower mid Sweden
    Not just that....

    Anyway, the mentioned issue of dissimilar output is very important. It could be what you opt for, considering that the ear is less prone to low freq's, but the rule of thumb is to keep it equal.
  7. Ok this might make me sound like a newb, but isn't the point of the acme set ups to be so that they get flat down to the lowest range? I would say the acme would be more of the sub and there would be much better mid/high range speakers. I figure that since the woofer in the acme is made to go low, there are probably competitors that beat it in the mids and highs. I also think that this is why it is quiet. Correct me if I am wrong.

  8. alexclaber

    alexclaber Commercial User

    Jun 19, 2001
    Brighton, UK
    Director - Barefaced Ltd
    If you're willing to import one Acme cab to make a bi-amp rig and you want that amazing studio monitor like clarity, why not just import a pair of Low-B2 cabs? Get the 8 ohm versions and match them up with a power amp that will put about 1500W RMS bridged into 4 ohms. Use one cab for small gigs, both cabs for larger ones. Works for me!

    The exchange rate is currently 7.3 SEK/USD which is the best it's been for over 5 years so they should be quite a bargain even with shipping and import costs added.

  9. brianrost

    brianrost Gold Supporting Member

    Apr 26, 2000
    Boston, Taxachusetts
    I'd contact Acme first and check where the 10" woofer is crossed over.

    You may find that in a biamp setup, the 10" is doing little or nothing.
  10. alexclaber

    alexclaber Commercial User

    Jun 19, 2001
    Brighton, UK
    Director - Barefaced Ltd
    I'm pretty sure it's crossed over at about 1000Hz so it does carry a lot of the mids as well as the lows. However for a small bi-amp rig I'd be more inclined to get something like an Epifani UL110, which is much efficient because it doesn't go as low. A UL110 with a Low-B2W carrying the lows would be a wicked bi-amp rig.