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A hole in my combo?

Discussion in 'Amps and Cabs [BG]' started by Dan Loader, May 16, 2003.


  1. I took delivery of my brand new Peavey Combo 115 2 days ago, it sounds amazing, especially with a lead guitar :)
    Before I bought it I noticed on Peavey's site that it has a rectangular hole, about 4" by 6" to the right of the main woofer. You can just about see it on the picture below:
    [​IMG]

    I'm not sure what this is for. Could I fit a horn tweeter to it? Or is it just because my amp uses the same mounting board another amp that does have a tweeter, and PV are just mass producing them?
    The TNT and TKOs both come with 1" circular tweeters, which leads me to believe that I could mount one if I wanted to.

    Could anyone help?
     
  2. tombowlus

    tombowlus If it sounds good, it is good Gold Supporting Member

    Apr 3, 2003
    North central Ohio
    Editor-in-Chief, Bass Gear Magazine
    That is your bass port. IMHO, it would not be a good idea to plug it up with anything. You might be able to add a tweeter to your box, but you'd have to incorporate a crossover, and watch out for impedance loading on your amp.

    If I were you, I'd leave it as is - at least until the warranty expires.:D

    Tom.
     
  3. Bass port? I'm guessing that's something like a sound hole on a hollow guitar.

    The 2x10TVX cab I have my eye on has a tweeter, so I don't have any need to mount one to the combo, I'm just interested :)
     
  4. The bass port tunes the cabinet. It's kind of like blowing across the top of a Coke bottle and getting the ship's horn type of sound. The same idea tunes the cab to about 40 Hz or so and makes the speaker and cabinet work together to make more sound in the lows. The hole size, cabinet size, and speaker characteristics all go together to determine the tuning frequency.

    Chris
     
  5. tombowlus

    tombowlus If it sounds good, it is good Gold Supporting Member

    Apr 3, 2003
    North central Ohio
    Editor-in-Chief, Bass Gear Magazine
    Your woofer is designed to work in a ported cab. There are a number of reasons why engineers would chose ported versus sealed cabs, and I don't have a strong enough knowledge of the topic to try and explain them in adequate detail. However, if the cab is designed to be ported, this is an integral part to allowing the speaker to work effectively in the box. If you put your ear down close to that port while you are playing (quietly, please! save those eardrums!), you should notice some very deep notes emanating from the port. In theory, this should be non-direction low notes, but placement, shape, and design of the port(s) is all part of a manufacturer's efforts to produce an amp that will have certain characteristics, volume, and tone.

    Not sure if this is helpful information or not, but there you go.

    Tom.
     
  6. It's a PeaveY BassXtendR (TM)

    No seriously. Almost every hifi, PA and bass speaker cabinet has a socalled "port". The port makes the cabinet into a resonator, really, tuned to a specific frequency, in order to boost the lower bass in such a way, that it picks up where the speaker itself starts to drop.
     
  7. Thanks very much everyone! It had be puzzling me for a while. Now I realise why it has a backplate aswell, otherwise the sound wouldn't be contained within the cab. Cheers!
     
  8. Hmmm. Crowded here. Three posts within a few minutes telling the same thing.