Need guidance in setting x-over points

Glowrdr

I just received all of my order for new speakers tonight, and I have to say that I can notice a world of difference already with these new M70's.

I did have to re-adjust my receiver to accomodate the new speakers and sizes, as you could definately tell my receiver was trying to compensate for something that was no longer there.

Being new to actually having to give a damn (lol) - whats the proper way about setting the x-over settings? Do I go strictly by the speaker specs, and set the crossover to match the low point of the speakers? Not sure what options there generally are, but I can set my points in 10hz increments. Currently my HK receiver has everything crossed at 40, and I believe my sub is at 120. I can choose the crossover point for every speaker as well (again, this may be normal, but I've never felt the need to pay attention previously).

Also, I was able to choose my sub size, which made me realize it was set to 8 this whole time (years), so I changed it to 12". Are systems smart enough to know whats best nowdays? Or should I be looking at the specs for the sub as well, and making these choices manually? I know some things definately know whats best for me, others are better off left in control of the user (DSLR anyone?)

So, if there is a hard and fast rule for this - do tell. Otherwise, if this is one of those things that depends on the speaker connected to the receiver in a certain sized room with howe many rugs... yadda yadda yadda - let me know and I can certainly just experiment and tweak things as needed.


Thanks again - hopefully I havent been too much of a pain in the past few days since I've been bitten by the bug.

whgarrett1394

I'm definitely no expert but I think that your sub is set to high @ 120hz. Your new speakers can go pretty low and all that overlap seems like it might be a problem. Maybe 80 for the sub, 60 for the mains. I think the M70 is 40hz @ -3db. Might be a good starting point and then fiddle around from there. There are a lot of variables and your ears tell you what you like best. You may not even need that much overlap, but I don't know how great the internal crossover in HK receivers is. Slope and such. Cheers.

ben62670

Set the XO point via the receiver for 80 on the mains and 80 on the sub. Turn the subs XO point as high as it will go on the sub itself.
Welcome to Club Polk
Ben

Knucklehead

ben62670 wrote: »

Set the XO point via the receiver for 80 on the mains and 80 on the sub. Turn the subs XO point as high as it will go on the sub itself.
Welcome to Club Polk
Ben

Thats exactly how I set mine...no issues.

kuntasensei

ben62670 wrote: »

Set the XO point via the receiver for 80 on the mains and 80 on the sub. Turn the subs XO point as high as it will go on the sub itself.
Welcome to Club Polk
Ben

+1. And if your AVR has a LPF of LFE setting (possibly just listed as a sub filter on your HK), 120Hz is the correct setting to fully pass the LFE channel. The crossover on the sub itself should always be turned to its maximum so you don't cascade that filter with the filters on the AVR and create a gap in frequency response. This also reduces the chance of filter-induced delay that can throw off the proper distance setting for the sub.

Glowrdr

The LFE LP FLT line selects the frequency setting....should you wish to make a change from the 120Hz frequency....

The setting for a 12-inch/305mm driver activates a 20Hz subwoofer high-pass filter

That sound about right for the sub? I'll definately change the rest of the speakers to 80 (I noticed a lack of low end last night, unless I was really pushing it). Also, I'm reading a little that says you should always set your center (CS2 in my case) to small. I currently have mine set to Large, thinking it could handle a little oomph. It sounds like for voice tracks - I do not want this (makes sense, I dont want boomy voices).

Sound like I'm on the right track? I'm not a complete noob when it comes to audio, but I realize HT stuff is new to me.

ben62670

Some people like the over voiced boom of crossing the sub higher than 80-120. It does sound louder, but not better IMHO. After listening to it at 80 for a while you most likely not want to go any higher.
Ben

BorisBoris

Can somebody give me some advice on crossover points as well? My sub does not have a knob on the back for crossover.. only for gain. It's an Onkyo SKW-110

My setup is:

M60s F/L
CS2 Center
M30s Surround + Rear

Currently I have everything at 80hz and the bass setting at LFE and crossover at 80hz as well



Thank you, didn't want to make another thread! Sorry for hijacking

jinjuku

Does your receiver have an Auto-EQ routine and Microphone?

You could always start there and see what the receiver setup and then use that as a point to start tweaking from.

ben62670

You're good BB.
Ben

Glowrdr

jinjuku wrote: »

Does your receiver have an Auto-EQ routine and Microphone?

You could always start there and see what the receiver setup and then use that as a point to start tweaking from.

Not sure who you were asking, but if it was me - then yes. I did use the autoset w/ the mic, and that's what gave me all kinds of screwy numbers. I think this is one of those times that I can probably do better than the auto-set can. I mainly like to use that for setting up speaker delays based upon seating. Otherwise the sound I'd like to take control over.

I'm going to have to double check what I originally put in the first post about the settings it auto-selected, but either way - something was missing. I could tell the sound was a lot smoother and cleaner, but something definately wasn't there. Could possibly be (1) x-over points, and (2) I never knew that I shouldn't be using sub crossover, so I've been doubling up (not sure what my receiver settings are/were, but it still appeared to me that I had full sub control using the dials - so I think the receiver was not crossing it over correctly)

kuntasensei

ben62670 wrote: »

Some people like the over voiced boom of crossing the sub higher than 80-120. It does sound louder, but not better IMHO. After listening to it at 80 for a while you most likely not want to go any higher.
Ben

I just want to be sure we're clear: There is no crossover for the subwoofer in any AVR. In the AVR, there are crossovers for the other channels that send bass to the subwoofer, then there's a low pass filter for the LFE channel (and JUST the LFE channel - not the summed output of the subwoofer line out). Then on the subwoofer, you often have a crossover control that is only active if you're using a speaker-level pass-through instead of RCA cables, or alternately, a low-pass filter (which is not a crossover).

So here's the bottom line:
1) The crossover/filter dial on the subwoofer itself should ALWAYS be set to its maximum or bypassed completely so that the AVR can handle all bass management.
2) The LPF of LFE (which many think of as a "subwoofer crossover") has ONE correct setting: 120Hz. The reason for this is that the LFE channel, on a digital level, is brickwall filtered at 120Hz by its very nature (which is what makes it the .1 channel, as it is only considered to take up 1/10th of the bandwidth of the other channels). If you set the LPF of LFE to anything below 120Hz, you are throwing away content that is meant to be reproduced by your subwoofer.
3) The LPF of LFE setting does not affect bass redirected from the other channels, which is what the channel crossovers themselves handle.

So why does the LPF of LFE control exist? It has one purpose: To maintain compatibility with subwoofers designed per outdated THX specifications, where the design calls for the subwoofer to only have flat response up to 80Hz. Regardless, this control will have little impact on the perceived level of bass, because surround mixers put very little content in the 80-120Hz range of the LFE channel. That said, there are harmonics of the sounds below 80Hz in the 80-120Hz range that give deep bass its perceived tone, which is what you will be tossing out if you set LPF of LFE to anything other than 120Hz.

And before anyone argues that there is a subwoofer crossover (because someone always does): A crossover is a combination of two filters - a low pass and a high pass - that handles the transition from one speaker to the other (in the case of AVRs, from each speaker to the subwoofer). The LPF of LFE is not a crossover because it consists of only one filter - the low pass. It doesn't redirect sound to any other channel, and no auto-EQ in the AVR will ever change that setting because there is no way to measure for it or any reason for it not to be set to 120Hz. On THX receivers, it defaults to 80Hz for compliance with THX specs... but both Chris Kyriakakis of Audyssey and Roger Dressler (formerly of Dolby) have confirmed in the past that the LPF of LFE setting should be set to 120Hz so that you don't truncate the content in the LFE channel.

kuntasensei

Glowrdr wrote: »

Not sure who you were asking, but if it was me - then yes. I did use the autoset w/ the mic, and that's what gave me all kinds of screwy numbers. I think this is one of those times that I can probably do better than the auto-set can. I mainly like to use that for setting up speaker delays based upon seating. Otherwise the sound I'd like to take control over.

I'm going to have to double check what I originally put in the first post about the settings it auto-selected, but either way - something was missing. I could tell the sound was a lot smoother and cleaner, but something definately wasn't there. Could possibly be (1) x-over points, and (2) I never knew that I shouldn't be using sub crossover, so I've been doubling up (not sure what my receiver settings are/were, but it still appeared to me that I had full sub control using the dials - so I think the receiver was not crossing it over correctly)

If your receiver has Audyssey MultEQ, I recommend running it, then changing the crossovers to 80Hz. Audyssey doesn't actually adjust system crossovers on its own. It sends the information about each channel's capabilities to the software in the AVR, which then sets the crossovers based on rules set up by the AVR manufacturer. Typically, you will get very good results by running Audyssey, then changing all crossovers to 80Hz with LPF of LFE at 120Hz (which Audyssey does not adjust anyway).

whgarrett1394

Thanks for the knowledge kuntasensei.