RM510 w/ Onkyo TX-SR875 Speaker Config

zero hectic

Hi all. I recently purchased an RM510 package (2 RM8, 2 RM7 and a PSW110) to go with my Onkyo SR875. I have the sub connected by the LFE input. I just ran Audyssey and something seems a little off. In my speaker config menu, my RM8s and RM7s are set at 150Hz, and the LPF of LFE is set to 120Hz. Does that seem right? I'm a bit of a novice at this, but I remember back when I was using the RM6800 set, my speakers where set at something like 120Hz. Can anyone more knowledgeable than I point me in the right direction, maybe give me some tips on other settings?

Thanks!

apphd

That 150Hz does sound a little high for those speakers. You can try running Audyssey again or go in and adjust them down a little maybe around 130-140Hz. Audyssey is not fool proof and does sometimes get things wrong. Try a couple different settings and see what sounds best to you. The lower -3db for those is 130Hz so you are not too far off. Maybe someone else can offer a little more for you on this.

kuntasensei

Audyssey is very much garbage-in/garbage-out, so lack of proper setup procedures (such as using the mic on a tripod, being out of the room during the tests, not placing the mic within 12" of room boundaries, etc.) can greatly affect the results.

LPF of LFE is NOT adjusted by Audyssey, as there would be no way to test for the proper setting. This has nothing to do with the crossovers for the other channels, and is only there for usage with speakers designed to THX specs. For THX style subwoofers, LPF of LFE should be set to 80Hz (since THX spec'd subs aren't meant to play back significant audio above that point). For pretty much any other subwoofer, leave it at 120Hz, since the LFE channel is brickwall filtered at 120Hz anyway. You want it to pass the full bandwidth of the LFE channel to the subwoofer. You'll see people claim that this would make your sub more easy to localize, but that's nonsense. Audio engineers rarely put anything above 80Hz in the LFE channel anyway, but the harmonics above 80Hz are important to the perceived tone of the sound in the LFE channel, even if they're not significant enough to be localized.

As far as the crossovers for the speakers, keep in mind that Audyssey detects the IN-ROOM performance of the speaker, which can vary wildly from the claimed anechoic specs due to interaction of room acoustics, placement, etc. Usually, you'll gain a bit of extension below anechoic specs due to acoustic reinforcement in the room itself (such as boundary gain), so you'd normally expect to see a speaker with a -3dB point of 120Hz possibly reach slightly lower than that when tested in-room.

You also need to be aware that Audyssey INTENTIONALLY doesn't set the crossover for that speaker at its -3dB point. Crossovers are a gradual slope, not a sudden transition, and normally you want to transition higher than the speaker's -3dB point so that you don't get a gap in frequency response due to the speaker's natural rolloff. For instance, in an ideal room, setting a system crossover of 120Hz on a speaker with a -3dB point of 120Hz can result in as much as a 6dB drop in the range near and just below 120Hz, since you haven't afforded enough above the -3dB point for the subwoofer to significantly take over bass duties.

Ultimately, 150Hz is not a bad crossover point for speakers with a 130Hz -3dB point, and is very likely only that low because the speaker is doing better than -3dB at 130Hz in your room. Ideally, you want speakers that can be crossed over at at least 80Hz to prevent localization. You will very likely hear the location of the sub when using speakers that have to be crossed above 100Hz, and there's not much you can do about that except step up to some bookshelf sized speakers that can troll below 80Hz.

And now, sir, you know how upgradeitis begins. If you have any other Audyssey questions, let me know.

Mike21

I have used Audessey with my Onk 805 about 6 times because I keep moving stuff around. Audessey has never adjusted my sub (now subs) right. I always have to do that manually.

Mr. K makes a great point about the -3dB issue. I never considered that.

kuntasensei

What about your subs isn't it getting right, Mike? Level or distance/delay?