in-wall speaker setup

[OptimusPrime]

I am trying to setup my home theater speaker system for the best possible sound production. I know that specs can only take you so far, and you really benefit more by gauging by ear and individual preference. Still, the science intrigues me and I really don't understand the way crossover ideally works.

I am trying to incorporate my old Yamaha sub (YST-SW015, 50-150 HZ, 70 W) with my new in-walls from MonoPrice.

Here are the specs of the in-walls:
8" Mains/Surrounds (52-20,000 HZ, 80/120 W), 8" Rear Surrounds (43-20,000 HZ, 80/160 W) 5 1/4" Center (freq. range not known, 50/100 W).

I am using an old Denon AVR 3330 receiver that I have had for a number of years. I am very familiar with the settings/options. Since I've been happy with this receiver, I am not ready to transition to a "built for blu-ray" AV receiver just yet.

The in-walls have a crossover switch (0, -3db, -6db). The sub has a high cut control from 50-150 HZ.

Based on these specs, what would be an ideal configuration? Right now, I have the in-walls all set to zero (default) and the sub set to high-cut at 110 HZ.

The Denon on-screen display gives the option of outputting bass to both the L/R mains as well as the sub, or the sub alone. Based on the size and specs of the in-walls, is there an ideal recommendation?

Finally, I'd be interested if there is anybody out there with a similar setup. This is my first speaker set with any type of crossover switching - so if your willing, please share your configuration. Thanks!

[Cholly]

I would guess offhand that directing bass to the fronts in addition to the sub would prove to be too heavy on the bass. I'd try with and without to see what sounds best to you. As to crossover frequency, you may be ok where you are, but you didn't provide enough information on the mains. At what frequency do they roll off by the selectable amounts? This will have an effect on your rolloff settings and the crossover frequency of the sub. In wall speakers can be kind of tricky, because their response is affected by the enclosed air column. If the lengths of the enclosed columns of the left and right speakers aren't the same, it will color their response characteristics.

[OptimusPrime]

I have since made some adjustments. On my receiver, I can either set the speakers to small ("when using speakers that cannot fully reproduce low sounds of below 80HZ with sufficient volume,") or set the speakers to large ("when using speakers that can fully reproduce low sounds of below 80HZ,") taken right out of the manual. So, after getting some help on the AVS forums, I set the sub's crossover to 150HZ, the highest it can go. I have the in-walls set to small, and the sub is carrying the low end well. Eventually - when I get a new receiver with HDMI, I'll probably pick up a new sub. I really cranked it up last night - and I am very impressed with the way everything is sounding together.

I set my sub phase to "reverse." I tried it both ways and it sounded better on it's default "reverse" setting.

After measuring the distance to the main viewing area in feet, I was also able to position the pivoting tweeters to directly bring it to "point." Despite once being a "doubter" that this could have a significant effect - I am happy to report that is has made a good difference.

I also turned the DB switch on the speakers to -6 DB. This significantly helped reduce any "hissing" that may have been heard when the speakers were playing at softer levels. I have my center channel set at +6, all the others are set to 0 (the top surrounds are set to +2).

I still want to play around with where I have my sub positioned. Do you have any other suggestions?

In summary, I am very satisfied with the MonoPrice in-walls. I feel I have a great matched speaker set that was very economical. They sound great with my older Yamaha sub and Denon receiver. When I run into some money I plan to upgrade my receiver to one that includes HDMI. I'd also like to purchase a terrific sub. Any recommendations for these items?

Thanks for your help and suggestions. I really appreciate it!

[OptimusPrime]

At what frequency do they roll off by the selectable amounts?

In wall speakers can be kind of tricky, because their response is affected by the enclosed air column. If the lengths of the enclosed columns of the left and right speakers aren't the same, it will color their response characteristics.

Oops - sorry - I forgot to respond to your question. Unfortunately, it wasn't included in the spec sheet and I have no way of measuring the roll-off frequency.

But - when I built my basement walls I made absolutely sure the enclosures were identical for every speaker. I even made sure to build a box for the ceiling speakers to improve their bass response.

I researched insulating behind in-walls too. Some say it was a good idea, others say it's no good. I decided to insulate and if I didn't like the sound I could always pull it out. So far, no vibrating or dampening. I think insulating was a good move in my case.