2-way bookself xo point

Hi all

I'm building a 2-way bookshelf for my mom to use with the tv (subwoofer to be added later) and some light lounge music.

The system employs a 4" mid-woofer and a waveguide mounted tweeter.

Driver selection was based on what I had in hand and I'm considering Rod Elliot's Parametric and Sub-Woofer Equaliser to smooth out the tweeter response - would that be worth the effort?

I'd be bi-amping the speakers (TA2020's for the tweets and LM3886's for the mid-woofers) and am thinking of 24dB/oct LR xo. I am a bit lost on the XO point - I'm not too good at deciphering an optimum XO point form the graphs... would someone help me with this:confused:

I used Fabien Lefebvre's MESSON app on my iPhone 4s for the measurements, the graphs are done in Excel with the exported data. I forgot to use the same gain settings for the tweeter and the mid-woofer, however, as I would be adjusting the gain at the active xo, I figure it would not present itself to be much of a problem...



I'd really appreciate guidance from the fine folks of this forum :)

Thank you in advance

Regards
 

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:hypno2:

Thanks for the replies guys :)

was out of town for a while, hence the delay in replying...

re:"4" mid-woofer and a waveguide mounted tweeter" do you make & model number?
I don't really think it's worth bi-amping a 2-way like this.
The graphs are a bit hard to interpret, it looks like a crossover freq of ~3Khz would work

Hi Pete

I'm not sure of the make and the model of the drivers..they are OEM units I purchased long time ago at a surplus sale...

One reason I've decided on the bi-amping route is because I don't want to use an L-pad for gain-matching the drivers. The second - I wanted to use the amps I already had, so I just needed an xo...

4KHz was my choice of frequency considering the FR of the drivers and Rod Elliot's articles on bi-amping...

However, I developed a vague notion about waveguides from my sporadic readings in this forum and was thinking - would choosing a frequency lower than 3KHz with a steep (24dB/oct) XO yield any benefit in terms of making the speakers act more like a point-source? Also, how does driver integration fit in to the equation?!?

It indeed looks like 3K for a crossover point will work just fine but you will have to dial back the mid-woofer by appx 8 Db to match the on-axis response of your tweeter.



-----------------------------------------------------------Rick............


Hi Rick,

The gain settings for the mid-woofer and tweeter measurement were not the same. This was an oversight on my part...the sensitivity of the drivers are much closer in reality :) I'l measure again, just to be sure :)