In-wall subwoofer?

[DIAR]

How do you guys feel about Peerless XXLS drivers. Are they worth the money in this kind of application?

The Win ISD Pro simulations look good. According to them I could build a vented enclosure and plug the hole if needed.

Which one would you build: 3 cubic foot box with XXLS or 1 cubic foot with XLS+passive?

I'll post excursion plots later

[DIAR]

How do I know how much SP I need...

[simon5]

Sound effects if you go to a good movie theater are around 105 dB at listening position.

Aim for 105 dB at 20 Hz on WinISD, it's a one meter measure but room gain will boost that so it stays at least at 105 dB at listening position.

That's a rough estimation, you may need less or more, I don't know!

[DIAR]

Thanks Simon. Sounds reasonable

[Drew Eckhardt]

Originally posted by simon5
Sound effects if you go to a good movie theater are around 105 dB at listening position.

Aim for 105 dB at 20 Hz on WinISD, it's a one meter measure but room gain will boost that so it stays at least at 105 dB at listening position.

That's a rough estimation, you may need less or more, I don't know!

While your theoretical peak output at reference level is 105dB from the main channels, the LFE channel is good for 115dB.

In practice Dolby Reference Level actually means that the dialog plays back at 74dB SPL. If the full dynamic range was used you'd get 105dB main channel peaks although most sound tracks are encoded with the dialog at -27dBFS. When I've checked I've never seen anything with more dynamic range so the loudest possible sound main channel sound is usually 101dB SPL. If you want to play with this you can look at dialnorm values and knock them off 105dB SPL. The LFE channel gets a 10dB boost so the theoretical and typical limits are 115/111 dB SPL.

Home DTS often has lower peaks when you normalize playback for average SPL - I've seen DTS tracks put the average level over 10dB closer to 0dBFS.

You may also playback at less than reference levels - I find reference -5dB to be a nice number. Combine that with the typically unused 4dB and you're at least -9dB from the theoretical values.