Bass Response on Dunlavy SC-IVa

What type of floor do you have these on? What are the problems with low frequency reproduction that you are encountering? Any type of footer or support components between the cabinet and the floor? Sean
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While i can dig up the facts / figures on this speaker, does anybody happen to have the crossover points handy?

I agree with what Tom / Audiotweak is saying in that the woofers are non-symmetrically loading into the room. Since all rooms have various ceiling heights, the results with this type of speaker will vary from installation to installation. Then again, this is true ( to varying extents ) with any design that raises the woofer(s) up above floor level / very bottom of the cabinet. That's because boundary effects are somewhat "set in stone" with a design of this type.

One will also encounter this with woofers that are stacked vertically but somewhat spaced apart from the other. This is especially true if the bottom woofer is already measurably up off of the floor. The larger Vienna Acoustics speakers suffer from this quite noticeably and even the reviewer in Stereophile commented on this. If i remember correctly, he went so far as to say that they were the hardest speakers that he's ever had to deal with in terms of placement.

Having said that, the staggered woofer array can be put to great use, but one would have to fine tune the spacing between the drivers and the crossover points for the individual listening area that the speakers would be used in. By "tuning" the output range of one woofer where the nulls of the other woofer(s) are occuring, the response sums to something that is much flatter overall. This is probably what Dunlavy was trying to accomplish, but without knowing the ceiling height and the distance from the side walls and how far they are pulled out into the room, there is no way to optimize the design.

Having said that, Dunlavy gives pretty specific placement suggestions for these speakers that seems to work quite well, but if you can't follow them, there are other methods that may work for your given installation. Only problem is, this requires a LOT of moving & listening, which large speakers like this aren't exactly easy to work with. Sean
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1) What are you using for an SPL meter?

2) At what distance were these readings taken from the speakers?

3) Where in the room were the readings taken i.e. at your listening position, standing up near the speakers, etc ???

4) How close were you to spl meter when taking the readings? If holding the meter, how far away was it from your chest area?

5) At what height were the readings taken?

6) Have you tried measuring one speaker at a time and then taking readings with both speakers operating?

7) Have you verified that the speakers are properly wired i.e. using the same polarity?

8)Is it possible to do a wider sweep i.e. one that shows the lower midrange response readings also?

The more that we know, the more that we'll be able to make constructive suggestions. Sean
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