Why would you choose.....>

Discussion in 'Home Theater Projects' started by Cam McFarland, Jun 6, 2004.

  1. Cam McFarland

    Cam McFarland Supporting Actor

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    one of these "Creative amps" over the next?

    I am considering using one of these amps.

    The SUB250RC, the SUB250RF with the bass boost disabled or the SUB250R with 4dB bass boost at 25Hz.

    I am in the process of building an "Adire ported" based sub
    using a Tempest driver. The room to be used in is approx. 20'x18', with 12' vaulted ceiling. There are (2)36" "hallway" openings in one front corner (one ea. wall of course), and a ~7' opening in side of exact opposite back corner.

    What would be the reason/s for using any one of these amps
    over the other....benefits, advantages, disadvantages?
    How would you choose a "custom" amp, or maybe why choose one, is a better question?

    I know these are all "extremely simple" questions to
    answer (lmao) so I am sure I will have more replies than I will be able to read. [​IMG]

    Hopefully I have included all pertinent info to make responses easier. Of course, I am counting my chickens as
    nobody might want to go to the trouble to answer, as I figure it would be a fairly involved reply, but what do
    I know.....



    Thanks,

    - Cam
     
  2. Allen Ross

    Allen Ross Supporting Actor

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    if you lived in canada and the shipping was dirt cheap,

    I think its the same amp as PE #300-793 but tweaked a bit more output, or like the rhythmic but with the remote controls thingy
     
  3. Cam McFarland

    Cam McFarland Supporting Actor

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    Thanks I guess,.....dont wanna sound rude, but you didnt really answer any of my "actual" questions....[​IMG]


    but then again...you did at least reply....[​IMG]
     
  4. Allen Ross

    Allen Ross Supporting Actor

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    so you are just comparing two amps, one with EQ and the other doesn't?

    well seems pretty cut and dry, if you need EQ, that would be a big advantage to getting that one. If you don't need it, get the one with out.

    As for the tempest in a ported enclosure, you don't really need the boost if you follow adire's specs, it should be flat, so i would get the one with out the EQ.
     
  5. Cam McFarland

    Cam McFarland Supporting Actor

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    THIS is some useful info.....but then.....what do you mean by "flat"?


    Thanks very much Allen..... [​IMG]
     
  6. ThomasW

    ThomasW Cinematographer

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    You'll 'know' by measuring the in-room performance. Your existing sub should provide adequate info for the decision.
     
  7. Cam McFarland

    Cam McFarland Supporting Actor

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    So, since my current sub has such a large jump at 30Hz.,
    & has no drop at 25Hz, I can theorize that I DO NOT
    need the bass boost at 25Hz.

    Gosh......I feel so smart. [​IMG]
     
  8. Allen Ross

    Allen Ross Supporting Actor

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    bass boost is a for of EQ [​IMG]

    by flat, i mean that with a normal amp it models flat, i only see major spikes around 60-70hz, room diffraction and other stuff thats above me.

    If its a commercial generic sub, not that i am saying it is, then most likely it has internal EQ(boost) to give you more output at 30 hz.

    Where is the sub located in your room? Move the sub around the room, see if you still have that 30 hz boost right in the center of the room, if you do then chances are the peaking you see is the subs fault not your room.

    my theory is start flat, if you need boost get a better driver, and to tame in room response get a BFD.
     
  9. Cam McFarland

    Cam McFarland Supporting Actor

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    Thanks Allen.....[​IMG]
     
  10. Craig Treusdell

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    I built the Adire alignment as my first diy home sub and was quite happy with it in a room wider/longer and mostly open on the back but not as tall as yours. I used a QSC RMX2450, bridged at first with 2400W. After several "pops", I backed off and used a single channel giving 750 watts. Still had problems overdriving it. I never used any bass boost or eq (except for running the gains a little high) and did not see any reason to do so. Stuffed it in a corner and it gave me plenty of deep bass.

    I bought a 250W plate amp from Parts Express, but before I installed it I picked up 2 Tumults (the Tempest was not cracking the sheet rock) and never got around to it. But I would bet that 250W is plenty of power with the Adire alignment based on the Tempest's near-death experiences using 750W. Most plate amps also offer signal-sensing turn-on. I wish my pro-amp did the same.

    If you go ported or PR'd and have the option, buy a plate amp that provides a subsonic (or infrasonic or rumble) filter, adjustable if possible. A class D/G/T/non-AB amp would be good too, but probably more expensive. 250W-350W. Auto turn-on. I don't consider the other options to be as important to the decision (such as remote, bass boost, eq, or low-pass filter). Parts Express has just this for $128 US (although it is clas AB).
     
  11. Cam McFarland

    Cam McFarland Supporting Actor

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    Craig......now that was absolutely AWESOME!!

    I have already ordered the SUB250RF with 360w @4ohms.


    Thanks.........[​IMG]
     

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