Crossover Advice

Posted by: Bayne

Crossover Advice - 08/09/13 12:01 AM

So, after a failed experiment with an Anthem MRX-700 I bought a Denon AVR-4520CI to replace my AVR-3808CI that needed to go to work in our living room. I've been playing with Audyssey MultEQ XT 32 and am in full tweaking-mode. I always second-guess the crossovers and was hoping for some advice. I'm using M60's for the fronts, a VP160, EP500, QS8's for surrounds, and M2's for the rears--all are v2, except for the VP160. Audyssey identified the M60's and VP160 as large and full-band, and everything else as small. It set the crossovers to this: M60 and VP160 as 40Hz, QS8 as 100Hz and the M2's as 60Hz. Sounds good, but I want to try for better. After reading up on the Denon-to-English Dictionary, I've set all my speakers to small and the Subwoofer Mode in the AVR to LFE+Main, but I'm unsure what to do about the crossovers. Any advice? Should I raise the Fronts and Center to 80Hz and maybe the Surrounds and Surround Back to 120Hz?
Posted by: JohnK

Re: Crossover Advice - 08/09/13 12:36 AM

Bayne, don't know what you read that led to a LFE+Main setting, but if the speakers are set "Small", that doesn't have an effect. All the frequencies below the crossovers set(including for the mains)are sent to the sub and it handles those plus any LFE that may occasionally be present during movies. The LFE setting is the appropriate one. The "+Main" is meaningful if the mains are set "Large" and are playing full-range. The "+" setting would then duplicate the low bass from the mains in the sub and isn't generally advisable.

For two reasons the crossovers set at 40 or 60Hz should be raised to 80Hz: giving the EP500 more work in the frequencies that it handles best, and since Audyssey has higher resolution in the sub channel, it equalizes it better than it would if those frequencies were in the speaker channels. The QS8s at 100Hz is apparently the best setting for their location, and should stay at that setting.
Posted by: Bayne

Re: Crossover Advice - 08/09/13 10:03 AM

John, I see what you're saying. I read that if you have a subwoofer, set everything to small. Then I read about avoiding double-bass by setting the AVR to LFE+Main. Re-reading the article. I see that I missied the bit about LFE+Main having no affect if the speakers are all small. Thanks!
Posted by: SirQuack

Re: Crossover Advice - 08/09/13 07:59 PM

Audyssey measures the -3dB point of each speaker in "your room" and reports that back to the Denon AVR. Denon and most other AVR's determine that a speaker capable of 40Hz should be set to Large, so it is actually the Denon that set that figure. In any case, I follow what most (including the mfg's of Audyssey) say that if you have a subwoofer in the mix, change those values to "Small" and adjust the crossover accordingly. For the M60's and 160 most likely 80Hz would be the best, but you could try 60Hz. I have my M80 and 180 setup to Small and 80Hz, but have experimented. I think my Q's are at 90Hz if I remember correctly.
Posted by: exlabdriver

Re: Crossover Advice - 08/09/13 09:15 PM

My Audyssey/Denon sees my M22s' as -3Db at 40Hz which surprised me a bit - I kinda expected 60Hz.

I've tried them at 60Hz & 80Hz but have settled on 60Hz. My system just sounds a bit fuller that way, but it could be placebo effect, ha!

TAM
Posted by: fredk

Re: Crossover Advice - 08/11/13 08:11 PM

Originally Posted By: exlabdriver
My Audyssey/Denon sees my M22s' as -3Db at 40Hz which surprised me a bit - I kinda expected 60Hz...

TAM

It could be you are getting a good bit of room gain with your placement. Are they close to a wall?
Posted by: exlabdriver

Re: Crossover Advice - 08/11/13 09:00 PM

Here are some pics of my HT in the Wall o Fame. The only difference now is a new Sony LCD TV & a VP100 on the lower shelf:

http://www.axiomaudio.com/blog/home-theater-pictures/?album=1&gallery=143

The system sits in a window alcove (11.5' wide by 2.5' deep) with the back panel of the M22s (perched on the 10" Velos) being about 18" out from the window/wooden venetian blinds. The front baffles are a couple of inches inside the front of the alcove but are far enough away from the side walls so as not matter too much I would think.

Despite my vehement discussions with another poster elsewhere who repeatedly says that they drop off dramatically below 80Hz. Whatever the reason, mine hold their bass extension way lower than that & work exceedingly well here in my medium sized, irregularly shaped room...

TAM
Posted by: JohnK

Re: Crossover Advice - 08/11/13 09:46 PM

Tom, I don't know anything about that discussion that you've had elsewhere, but I certainly can confirm that the M22s have strong response to well below 80Hz. They would appear to drop rapidly below that frequency to someone simply looking at a graph taken in an anechoic chamber which doesn't give accurate numbers below about 80-85Hz. The impedance curve indicates(from the bass dip minimum)that the enclosure is tuned to the high 50s of Hz. Beyond this, support in the bass from closeness to room surfaces or the separate factor of "room gain"(the smaller the room, the more the gain at very low frequencies)would give further bass extension in typical listening situations.

As I've reported in the past, in my own setup the M22s give strong output down to about 50 Hz, and much weaker, but still audible output to about 40Hz. Nevertheless, I still cross them over to the EP500 at 80Hz for the stronger performance in the 40-80Hz octave which it provides, together with taking some of the low bass burden off the M22s so that they can play more cleanly higher up.
Posted by: wilwom

Re: Crossover Advice - 08/12/13 07:39 PM

Originally Posted By: JohnK
Nevertheless, I still cross them over to the EP500 at 80Hz for the stronger performance in the 40-80Hz octave which it provides, together with taking some of the low bass burden off the M22s so that they can play more cleanly higher up.


+1

When you have a really good sub it should be used for that portion of the audio spectrum. Especially when your receiver has Audyssey MultEQ XT 32.
Posted by: Bayne

Re: Crossover Advice - 08/13/13 02:11 PM

So I raised all of my crossovers to 80Hz and left the QS8 at 100Hz and changed LFE+Main to LFE. Everything sounds great. The base is smooth, like really good milk chocolate. I'm very happy with it now. Watched several movies and both the Mumford & Son's and Sully Erna's concerts on Blu-ray. Makes my system sound like it's all new. Thanks for the advice!
Posted by: tomtuttle

Re: Crossover Advice - 08/14/13 12:25 PM

Isn't it *possible* to have room nodes in the 60-80Hz region that might be mitigated by setting a lower crossover when using floorstanding (full-range) speakers?
Posted by: Adrian

Re: Crossover Advice - 08/14/13 12:43 PM

Good point, Tom. I believe using a lower crossover point with might be beneficial by evening out the base throughout the room, as long as the speakers in question are capable of putting out clean/lower freq's. Kind of defeats the purpose of full range speakers if they are crossed too high, imo.
Posted by: exlabdriver

Re: Crossover Advice - 08/14/13 01:07 PM

From what I've been reading elsewhere, the wisdom now (FWIW) is that the extra capability of floor standing towers (bass-wise) is largely wasted in HT applications if capable sub(s) are used. Their argument is that there is not a lot of point of towers if the AVR is filtering bass from them.

Speakers in the size & class of the M22s I think are ideal when combined with sub(s) & generally are a lot cheaper than the floor standers. That's why I went that way for both HT & one of my audio only systems (M2s + EP400s).

Works for me...

TAM
Posted by: whippersnapper

Re: Crossover Advice - 08/14/13 08:42 PM

Having lived with M22s as the mains in my home theater for a good while now, I have to agree. I had originally planned/hoped to go with M60s but just couldn't work the budget. When it finally dawned on me to change to the M22s, everything fell into place. They fit nicely on stands beside the TV, they produce a wonderful flood of clean sound, they blend perfectly with the VP150, my sub does the heavy lifting, etc., etc.