Advantages of using a higher x-over point?

Vaughan Odendaal · 10-30-2005, 11:59 AM

Hi there,

Over the weekend, I was experimenting with my equipment. I have an SVS PB-10 ISD and I have Whalfdale Diamond 8.4 front speakers, center and Diamond 8.1's for rears. I know, they are quite old speakers, but I think they still sound great.

Now, since I've had my SVS subwoofer, my bass has gone through certain phases. At first, the bass droned on and on and there was a lot of overhang. I didn't know what was causing this. Two months later, I found out that I had the phase set on my reciever as "reverse" instead of normal.

I changed it to normal and the bass was more in sync with the mains, with less obvious bass overhang. But the bass was still a bit "thick". Now I know that the room contributes towards the sound in a big way and I have no treatment to speak of.

However, this morning I changed my crossover point from 80hz to 60hz. All of a sudden, the bass firmed up. There was almost no overhang to speak of. No lag. But there was slightly less bass (not as boomy as it was before).

The bass sounds precise and "quick" now. With films, I'm still getting the same very deep bass that I feel with films (I don't think I'm missing anything at all), and when there is music, the bass just sounds precise.

I also noticed that if I change the x-over point from 60hz to 80hz, there are more high frequencies.

Can someone please explain to me what I'm experiencing here. Why I am getting less overhang with a lower crossover point and why there is less boom?

I don't know if the high frequencies sound better at 80hz or 60hz, I honestly don't know because I have no frame of reference in which to judge. But the bass sounds absolutely wonderful with the 60hz x-over point (arguably better than with the 80hz x-over point).

Your thoughts?

--Sincerely

SethH · 10-30-2005, 09:25 PM

I can't explain it. At first I thought you might be losing the frequencies between 60 and 80 when you dropped the crossover, but according to the Wharfedale website, the 8.4's are good down to 30. It may be that you had a large peak somewhere between 60 and 80 and that by dropping your crossover point your speakers are sloped lower at that peak frequency, thus reducing the peak -- but I could be completely wrong.

Anyway, the key is that you should use what sounds better to you. If you can set your crossover between 60 and 80 then play with it more. If you can't, then leave it at 60.

Wayne A. Pflughaupt · 10-30-2005, 11:43 PM

In lieu of “before and after” room response curves, we can only speculate. A good place to start is that you had a peak in response in the 60 Hz region that crossing over there helped smooth out. If your mains have weaker output at 60 Hz than at 80 Hz, that would also help this theory along.

Regards,
Wayne A. Pflughaupt

Jacob C · 10-31-2005, 12:19 AM

another issue could be the location of the mains vs. the sub. Similar to moving your sub around in your room. It sounds different at different locations.

MikeyWeitz · 10-31-2005, 04:44 AM

Yep, as soon as I read you post, a peak @ the 70-80hz range is what 1st came to my mind.

**HTF Ads**

Vaughan Odendaal · 10-31-2005, 05:56 AM

Thanks for the responses, guys. You know, I've tried placement. You don't even want to go there.

But if I leave the subwoofer in it's present location and change the x-over point from 80hz to 60hz, the bass is just so precise sounding. There is no bass lag.

At 80hz, the bass sounds a little bit muddy with music. Now I know this shouldn't be used as a reference but I'm using satellite as an example. I've got around 50 or so dedicated music channels. It sounds great, but obviously not 100% cd quality.

I tried the Foo Fighters cd (latest album), and with an 80hz x-over point, the bass sounds like it's dragging on just a little bit. But if I change the x-over point, the bass is more agile, sounds more precise, but there is slightly less apparent bass.

I never thought that I might have a peak in my response at 80hz. So lowering the x-over point would help with peaks?

And I just would like some input from those of you who have tried the same x-over point. Have you guys also noticed an improvement in bass articulation by lowering the x-over point from 80hz and down?

I'm sorry I can't give you more in-depth information about my room response but I have no SPL meter at present.

Thanks a bunch.

--Sincerely,

Vaughan Odendaal · 10-31-2005, 06:02 AM

Sorry, I just wanted to add that I have my speakers all set to small on the receiver.

--Sincerely,

SethH · 10-31-2005, 07:34 AM

Quote:

I never thought that I might have a peak in my response at 80hz. So lowering the x-over point would help with peaks?

Vaughan Odendaal · 10-31-2005, 07:54 AM

A question: is the 60-80hz bass region the most critical when it comes to music? Would that region cause a "thick" sounding bass if there were peaks in the response?

The thing is, I don't know if I'm getting peaks because I can't measure it, but if someone could let me know what the effect would be if there were peaks it might help me understand what is going on.

In other words, do my observations correlate with a peaky response in the 60-80hz bass region?

With regards to phase, I've played around with it for a long, long time and I've found the best position for it while playing a music dvd (Eric Clapton Live in Hyde Park), so that is sorted out.

Thanks for helping.

--Sincerely,