48db/oct crossovers causing listening fatigue?

[puppet]

Originally Posted by tvrgeek

My recent experience is dealing between the mains and subs. I find the steeper the better. 4th or 6th electrical. From listening to others speakers, some of the best have had very shallow crossovers. I just have never found drivers I thought suitable for first order electrical. As was commented on before, it could also depend a lot if you are aligning the crossover with the acoustical rolloff. I don't always do that due to staying away from breakup or just too much distortion in the drivers lower end.

There is a lot of personal preference on this apparently. Steep slopes in the area you describe certainly do the job but I find that the system as a whole lacks some dynamics as a result of the higher order filters. Bass lines and a pianos lower register sound thin(ner) to me. A third order elec. seems like a nice compromise to my ear ... even though the Bessel adds a slight bump here (around 116hz) ... I'm very OK with that.

[DougL]

Another subjective opinion.
While playing with the DCX2496, my impression was that the LR24 might be "better implemented" than the LR48. Something simular could be an issue with the Mini-DSP.
I have no proof, but I picked drivers with wide overlap for my first project so I could try different crossover orders, types and points.

[Pano]

Originally Posted by ra7

What are you saying, Pano?

When choosing crossover points and slopes most designers talk about FR, power response, out of band, polar response - all of them important. But I never see discussions of harmonics.

A lot of what gives different materials their "sound" - paper, metal, plastic, kevlar, etc is the harmonic structure. If you truncate those harmonics too soon or in the wrong place something will sound "off". The ear expects to hear certain things, if it doesn't they will sound odd.

Not something you read much about, but it's an important consideration when picking drivers and designing crossovers.

[Barleywater]

Originally Posted by DougL

Another subjective opinion.
While playing with the DCX2496, my impression was that the LR24 might be "better implemented" than the LR48. Something simular could be an issue with the Mini-DSP.
I have no proof, but I picked drivers with wide overlap for my first project so I could try different crossover orders, types and points.

I've worked with DCX2496 a lot, and have captured IR for both filters; very text book. Each when properly aligned sounds near identical at moderate levels with music program. Stress becomes apparent at lower power levels with LR24.

[Boden]

Post 42 by Ra7 so far is one of the few posts that gives the correct picture.

Most of the posters here seem to think you can treat XO filters as separate beasts and make far reaching statements about the audibility of electrical transfer function as such. That is simply not correct.

Loudspeaker and XO should be treated as one. It is the combined filter plus driver acoustic output that matters. Only that way will the drivers sum correctly. Often the XO also has an equalizing function for baffle step and driver peaking. There should not be much of a difference between the transfer functions of active vs.passive.

Sometimes even a properly optimized 2e order electric will produce an acoustic LR4. There is no way a designer can evade measuring drivers in the enclosure that will be used and import the results in proper XO software, such as Leap, Calsod, LspCad. Standard calculators are completely useless here.

Simply playing with textbook filters of your DCX or MiniDSP will get you nowhere, because the summed SPL is all over the place. Once you have obtained flat on axis on 1 meter or so, and have also obtained a deep nul at the XO by reversing polarity of one of the drivers, you are on safe ground and have a starting point for any discussion.

Regards,

Eelco

[Scottmoose]

I imagine that is because most of the posters simply haven't thought it necessary to state the obvious.

[DavidL]

I get into "trouble" a lot on here for stating the obvious.

[Scottmoose]

[thalis]

True, there are a lot of things that change with changed crossover slopes (order), but I almost always found that 8th order slopes sounded worse than 4rth (and 4rth from 2nd), in middle frequencies (not in a sub), and with drivers that were working well within their “comfort” zone, even with matched driver directivities at the point.
Reasons could be (among many): differences in phase response (gr.delay), in dynamic response regarding power margin / distortion rise vs power / flux intermodulation in the v.c.-magnet assembly etc. (abrupt changes vs progressive integration), abrupt vs progressive change in the height of the sound source.

[tvrgeek]

Originally Posted by puppet

There is a lot of personal preference on this apparently. Steep slopes in the area you describe certainly do the job but I find that the system as a whole lacks some dynamics as a result of the higher order filters. Bass lines and a pianos lower register sound thin(ner) to me. A third order elec. seems like a nice compromise to my ear ... even though the Bessel adds a slight bump here (around 116hz) ... I'm very OK with that.

I should mention, I usually cross at about 60 to 65. That leaves 99% of the music in my main 6 1/2 inchers. My experience is any lack of punch in the bass is far more likely limitations in the upper bass. Frequently that may be a dip caused by sub phase-time mismatch causing a dip. For me, sub position and step crossover avoid that.