Axiom Home Page Forums General Discussion Home Theater Bass Management

I have an EP800, M80 mains, VP180 center, and M22 rears. Using a 250 watt five channel amp at 8 ohms (500 watts at 4 ohms), would the conventional wisdom be to have the crossover for my front three speakers set at 60 Hz and the rears at 80 Hz? Does the 60 Hz crossover for the entire front soundstage put considerably more strain on the amp? Is anyone doing 40 Hz for the M80s and VP180? Thanks.

I use a 40 Hz crossover with my little ol' 75 WPC receiver.

There you go. I bet you have little to no sub localization.

Well, not with the 100Hz and 120Hz crossovers for my center and surrounds.

I’ve varied between a 40/60/80 crossover for my 3 M80s L/C/R depending on the situation. Right now I’m using 80 because the SVS AS-EQ1 actually makes the bass sound much better with the EP500 than the M80s alone. W/o the SVS AS-EQ1 I use 60Hz in this room since I hear no advantage to going lower. In my apartment were I sat 6-8 feet away (not like 11-12 now) I could better feel the mid-bass punch by lowering the crossover to 40Hz across the front.

In any of the cases I’ve never shut down or clipped my Denon 2807 at 6-8 feet or Onkyo 3007 at 11-12 feet playing at and average 80dB calibrated level.

I think what works best is very room/seating location dependant and best determined by experimenting.

Dean

My personal settings ended up being pretty close to what Audyssey adjusted for my room characteristics.

m80's at 60hz (however using multiple subs 80hz can be better as the sub does a better job moving air in those lower freq's)

vp150 80hz

qs8's 90hz

LFE above 80 becomes directional. I used to have my surround channels set to 90 and 120, per Audyssey, but it drove me nuts. Dropping them to 80 made the LFE much more enjoyable. My fronts (M80’s) are set to 40 and my center channel (two M22’s and one VP150) is set to 60. Different room configurations and characteristics will affect optimum set up, but I would still refrain from setting LFE above 80.

If you have Audyssey turned off, that is ok to reduce the crossover setting, however, you only want to increase the number with Audyssey engaged. Otherwise, you are losing material between what you reduced it to, and Audyssey's results.

I am not sure what you mean by "losing material". I think you will find that when you lower the crossover from what Audyssey suggested that you do not have Audyssey processing in that channel for the frequency range that is below the crossover that Audyssey calculated.

That was my understanding as well.

That’s also my understanding that you just don’t get the Audyssey EQ below where the original crossover was set by the receiver. OTOH the LFE channel filter Audyssey applies is suppose to be much “finer” than that of the other channels so theoretically the signals going to the LFE channel are getting “better” EQ. Or like me you can just turn Audyssey off.

But you are using an AS-EQ1 aren't you?

I'm glad I don't have that kind of wizardry with Rotel (I'm not knocking it; I'm sure Rotel didn't want to pay the licensing, and perhaps that savings made my pre/pro a better "value" -- I'm certainly not missing it).

Question: For those with M22s, do you use 60 Hz as a crossover? I do feel my M80s and VP180 work well at 40 Hz, and I like the idea of having a difference no greater than 20 Hz in the handling range of the fronts vs. rears (maybe that's a silly notion). So I'm going with a crossover of either 60 front/80 rear or 40 front/60 rear, but maybe M22s are just ideally suited for the tried and proven default of 80 Hz.

Blu, when I ran Audyssey, the measurements taken, in co-ordination with the standard set by the receiver manufacturer, resulted in a 60Hz crossover setting. Nevertheless, I wanted the EP500 to do a little more and take more of the lowest bass load off of the M22s, so I manually reset the crossover to 80Hz, which led to excellent sound without sub localization.

Makes sense. That's where my head is, too. But then, according to Alan, a head and two ears don't... well, you know.

Yes I use the AS-EQ1 which is a form of the Multi-EQ system however, it only works below 200Hz so it doesn’t screw up the rest of the FR range. So when I say that I turn Audyssey off I’m talking about the receiver. If there was a way to only use the LFE curve in my receiver I would do that but Audyssey is all or nothing in my Onkyo 3007 and I don’t even like using the “Flat” curve anymore.

AS-EQ1 does work quite well. However, the LFE EQ on my Onkyo is only marginal at best since its not as robust as the AS-EQ1.

Is it a good idea to run Audyssey just to see the EQ applied and then switch to manual EQ and actually only use the values calculated by Audyssey for the low frequencies (let's say below 200Hz) and leave the rest un-EQed (0dB).

Unfortunately the values shown in the user interface, and those which can be manually entered, are not the whole story. Audyssey, computes and uses other information which you can't manually enter. So it's either use all which Audyssey gives you, or go with the lesser manual settings.

In addition the EQ curve used by Audyssey in general, even more so below 200Hz, uses a finer filter than what is allowed in the manual EQ settings. So even w/o the other information Audyssey uses switching to manual doesn’t even give you the same EQ.

Yes, Bruno; as Chris and Dean point out, there's no way to manually duplicate the Audyssey measurements in certain frequency ranges. As Dr. Kyriakakis(with some irritation)points out, the manual parametric equalizer isn't part of Audyssey and is a "crude"(his word) approximation of a small part of the results.

Thanks guys.