I'm only guessing here. Perhaps because some cables purport to maintain absolute phase better than others. Only single driver and 1st order cross-over speakers maintain absolute phase. Of course the skeptic might say that sellers feel the need to provide a reason for all the cable options and a means to qualify their suggestions.
40 responses Add your response
I think that's one of those things that boil down to a matter of taste. Most people in audio are trying to build a system that serves their music, and gets out of the way. Some people are disturbed by phase errors or certain types of distortion, and some consider these acceptable trade-offs.
I personally prefer time and phase coherent speakers, although I have none in-house right now. I was raised on Vandersteens, and these kind of speakers just seem to serve the music better over the long haul. Of course there are only a few companies making this kind of speaker, now that Meadowlark is gone. The parameters that are needed to make a first-order speaker go are more limiting to a designer than than say fourth-order ones.
Unsound you're partly correct on the 1st order=correct phase. Until recently I thought all 1st order crossover speakers maintained correct phase.To my dismay there's a couple of imposters in the group.Sonus Fabers and some Dynaudio speakers have their tweeters and midrange drivers wired in/out of phase or the bass drivers are wired in/out of phase.The drivers in these speakers aren't all wired in positive polarity together.
I started a thread on this a while back which turned into a sometimes heated and very informative discussion. I'm no computer whiz so I don't know how to locate the thread and provide you with the link. But I bet someone, perhaps yourself Blindjim, can locate it and I would recommend you do. I heard from everybody from Jeff Joseph of Joseph Audio (who uses very steep 4 order filters) to the guy from Green Mountain Audio (can't remember his name but a proponent of first order designs). Also, check out Richard Hardesty's "Audio Perfectionist". He adheres to the first order mantra. After much reading and reflection I came to the conclusion that you need to design the crossover to work with the drivers you have selected and the overall design. This is much more important than phase coherence. Can even the best drivers operate far outside their natural frequency response limits in a 6db slope design--I have my doubts. Should all drivers be shut down radically so they operate within a fairly narrow range of frequencies--I don't think so either. I am of the opinion that the dogmatic approach (i.e. must use first order, must use 4th order) doesn't make a lot of sense. Rather, the crossover should be tailored and tuned specifically to complement other aspects of the design (intended use, drivers, bass loading, etc.). Of course I'm no expert and you should read some of the literature out there for yourself to form an opinion.
Gmood1, you'r absolutely correct. The crossover is only 1 design aspect necessary to maintain correct phase in a multi-driver speaker. It is how ever a pre-requiste. My narrow answer was in response to Blindjim's question as to how it may effect cable selection. Mind you I'm a bit dubious about the very premise of cross-overs determining cable choices. As to whether they're best, well to me the best would be no cross-over. Unfortunately, that would usually would require compromises I'm not willing to accept. That said, I favor 1st order cross-over designs. I fully accept that other may have different priorites and that other options may better suit their desires.
1st order is 6db, 2nd order 12db, 3rd order is 18db, correct?
A lot from what I gather here is the ability of the manufacturers to blend the drivers well. Some companies use steeper crossovers (18db will cut off the signal much more sharply than 6db) to prevent overlap.
So, no matter what slope is being used, a lot matters with the driver selection and boxes.
I wouldn't buy a speaker based on crossover design unless I was looking at NO crossover. However, a 4th order crossover is much harder to make and more expensive. So, you have to factor in the quality of components used if you look at 2 equally priced speakers with similar drivers-who is cutting corners to allow for crossover components?
Unsound...Where did you (and a lot of other guys)get the idea that a first order (6 dB/oct) crossover has no phase shift? Actually the woofer and tweeter phase varies with frequency, but always differs by 90 degrees. The tweeter can be physically positioned so that at some particular frequency, usually the X/O frequency, the two drivers are in phase. As you get away from the X/O frequency the phase difference between drivers becomes unimportant because one or the other is attenuated. Inverting the polarity of one driver changes the phase discrepancy from plus90 to minus 90...take your choice.
Polarity inversion makes more sense for a second order crossover, where the phase discrepancy is 180 degrees. The selling point for fourth order, apart from the 24dB slopes, is that, with 360 degrees of phase shift the drivers are in phase. Fourth order is difficult and expensive to implement with a passive speaker level X/O, but quite easy for an electronic line level crossover.
I don't think many speaker designers would use the same drivers for a 1st order cross-over as they would for a 4th order cross-over. The very reason for using a 4th order would probably be to avoid that much over lap and to maximize particular drivers strengths. On paper a 1st order-cross over appears to be the simplest and cheapest. What not may be immeadeately obvious is that most manufacturers who choose 1st order crossovers go to great lengths to use first order cross overs towards a final goal. That goal being a time and phase coherence at the listening position. Thiel even goes further to present the amp with a steady load. These cross overs are far from simple. They compensate for driver irregularites, box resonances, etc. First order cross overs are only 1 step towards a final goal, these cross overs are tweaked along with many other designer considerations. The cabinets are time aligned which can add greatly to manufacturing costs. The drivers themsleves usually need to be capable of greater range. To suggest that first order cross-overs are a cost cutting decision is short sighted. Unless one is designing their own speaker, judging by isolated compenents to determine the value of a speaker is fraught with problems.
Correct you are.
And after listening to many different speakers in many different price ranges, Vandersteen speakers sound the most correct (realistic) in their respective price ranges, and even when compared to higher priced models. Geeze, did I piss away money before wising up!!!!!!
Beware the quicky listening tests at dealers!! Can you live with the speakers in your own home for years after the purchase? Why do you see SOOOO MANYYY speakers on this site for sale? I bet that most have a problem area with certain music in the living space that makes the owners want to "upgrade".
Just an idea...
I think understand..it's similar to what a baffle step correction circuit does for my speakers. The amplifier sees an almost constant 9 ohm load. This makes the impedance flat from 100Hz all the way passed 20Khz. Also the phase angle is nearly zero in the same frequency range. There was a time when I didn't think this stuff mattered.I know better now as I can hear the difference.
Gee. . . thanks. to clear up something before it getts too far afield...
the note regarding speaker cables is ONLY where I derived the info as to what speaker is in use or may be in use... the cable guys expanding on that theme of possible speakers then provided some of their insights on First, Third, fourth order types of speakers. I, as some of you, did and do not see the correlation between cables and the type crossover being used in a given loudspeaker.
As with most of the audio realm, murkiness prevails. I agree that time and phase coherent speakers, although picky to setup IMO, provide a very coherent and larger sound field... or such is my limited experience.
The thrust of the thread was/is to delve into characteristics of given first, third, fourth order crossover designed loudspeakers. Both positive and negative traits. So thus far, I gather the higher the order of crossover, the strickter the field of operation. No wiggle room, or certainly less so, correct?
Also I've gleened no actual determination of a good, better, or best scenario exists soley on the basis of how low or high the order is in application & design. Correct?
My aim was/is to gain some more solid footing in finding which design, creates more fluidity, and natural a presentation, on average, and is not dependant upon a particular sort of amplification.... with the understanding an increase in sensitivity of loudspeaker is accomodating to those amps of lesser power capacity. The key, so far as I am concerned is not the available power, but the way it is handled. though I might be off track with my thinking here, I'm looking to find a design that is accomodating to music, more so than power or the lack of it. Personally, I'm sold on the notion of more power equals more control... and saying that I realize much of the sound is genrrated in the first 50 wpc. A good bit, if not all. Its impact however, imaging and sense of realism, for me, seems to come a bit further on up but then, Im no engineer.
I got the impression from speaking with certain manufacturers a discernable or audible difference is apparent between speakers with different order designs like a thumbprint so to speake. Im not so sure. B&Ws in general use a higher crossover, Monitor Audio, another English unit, uses no caps whatever for crossovers VSA, again a higher ordered crosss and the same with older Phase Technology three ways. Ive owned several of the B&W two way & three way units. The Gold 60s from Monitor Audio, three way and two way PTs, and now the 4JRs. the latter when set right does provide a striking field of sonic involvement. That being said, as with the BWs, I do notice specific spots where the music seems to end with some abruptness. Not a terrible thing, but one Id like very much to avoid on the next set of speakers I get. Hence, my curiosity.
I quit reading after the first 60 or so threads, or rather the PC quit reading to me maybe its got a high crossover as well.
Any further thoughts to clear up my ignorance in this regard, or add to another's enlightenment, are greatly appreciated.
Blindjim, with all due respect You might be a bit off base with some though certainly not all of your assumptions. Many of these issues can and have been argued here ad nasuem. While I admire your approach, perhaps it might be best to just use your ears and determine what you seem to like and then determine if there seems to be any correlation or similarity between those systems/components. From there you might find a springboard into the archives and into the current and future forum to confirm your impressions and perhaps open your horizons to other gear that might fit into your personal preferential hieracrchy. Good luck.
For the people that haven't seen it.Here's a nice little walk through by Pat McGinty on Time Coherence and how to read a step response of a loudspeaker..The Step Response Reveals All.Of course time coherence is just one part as speaker design is quite complicated atleast for me.
I am a fan of first order crossovers and Thiel, Vandersteen and Meadowlark designs. But to get back to the basis of this thread I feel it is simply hogwash and marketing hype for any cable manufacturer or dealer to say that certain cables are/are not appropriate specifically for first order designs. The electrons couldn't give a rat's ass about phase effects in the wire; that is simply silly snake oil mumbo jumbo. While I am convinced from first hand experience that cables do make a difference in sonic quality, this imparting of anthropomorphic behavior to electrons is complete horse hockey. Go with the cables that sound best, not those which some cable marketeer tells you is compatible with the electronic bahvior imparted by the freakin' crossover design. Man, it really gets my goat when good people on agon get messages like this from industry jerks with nothing more than $$$ signs in their eyes.
Blindjim, you are a good man, don't fall victim to this nonsense. Would you care to share those particular manufacturers with us?
The complexity of the X-over will effect amps differently,as the back EMF will have different phase angles.Simple 6db/oct reduces this effect and is more agreeable to small set amps.
The order of x-ver is generally determined by the drivers used,their frequency response and resonances outside their operating spectrum.Many manufacturers will take a great tweeter and run it as low as possible using 3rd and 4th order x-overs.When using these crossovers the mids or woofer are wired out-of-phase to bring them back into phase.
I believe simplier is better,but when designing a 6db/oct system,sometimes it is best to use a L-pad on the tweeter.This prevents the x-over from changing as the impedance of the driver changes over its' range.Having just built a speaker system of this design premise,I understand the difficulty involved.Frequency respomse abnormalities,over excursion of drivers and phase coherency are all balls to be kept up-in the-air during the juggling routine.
However, a 4th order crossover is much harder to make and more expensive.
This is the opposite of what I have been told; first order done right is not an easy task.
Also, and correct me if wrong, the advatage of lower order cross overs is less parts in the signal path, therefore less to degrade the signal.
Brianmgrarcom...Take a look at the schematics for first and fourth order X/O, and think again about which is more difficult and expensive to design and build. However, your comment about having fewer components in the signal path is very valid. IMHO this, rather than phase issues, is the chief advantage of the first order X/O.
I have a hunch that manufacturers who use first order crossovers, often for very good technical reasons, feel vulnerable to accusations that they are looking to save cost, and respond with marketing hype and the suggestion that their crossover design involves some mysterious art.
Crossovers are a necessary evil. Even the so-called "full range" drivers have crossovers...mechanical crossover that causes only a small section of the cone (sometimes a separate section called a "wizzer") to vibrate at HF. The only truly crossover-free driver is an electrostatic.
here you go again! As Dodgealum pointed out there was a thread started by Rbischoff on 9/14/02 on this matter & there are some 160+ posts on the matter incl many informative ones by Roy Johnson, who is the owner & designer of Green Mountain Audio. Here is a link to that thread:
it'll be worth your while to read it all of it. There is some great info in there.
Then member Gmood1 started a thread on the same matter on 8/5/03. Here is a link to that one:
it'll be worthwhile to read this one too.
And finally, here is the link to the thread Dodgealum started on 4/11/05:
i know that it must feel that I'm the historian on this matter!! :-) not so! I'm very interested in this particular matter hence read these threads w/ much interest.
Here is also a very good write-up by Elliot Sound Products (Rod Elliot):
worth reading! this explains Eldartford's comment about 1st order having phase shift but its remaining constant over freq.
a little search of the archives you have yielded this, my fellow A'gon member!
Brian, on the surface a 1st order crossover would seem to be simpler, having less parts in the signal path.I wasn't saying a first order is "simipler" (to design), actually just the opposite; while it has less parts it can be harder to get right. Unless by "simpler" you mean the finished design is simpler than a more complex higher order.
I can't argue with the rest of what you said...not that I am arguing anything, I don't know enough to do so! :)
Let me close with this, in theroy, the less a signal has to "go through" the better, yes? (I am not saying all first order designs are guaranteed to be better.)
I didn't want to bias any opinions, color any insights or cause any undue discourse by throwing in the names of those cable manufacturers that made mention of their applications with different speakers crossovers... though they brought it up, not me. they are prominent and popular wire makers, for sure. I own some of their products myself, and am most pleased with the preformance, which is what ushered me to go back and check them out once more.
Everybody is trying to make the best item they can. Of that I'm positive... some fall short... some don't have resources enough to attain the goal... and with such a plethora of designs and configurations of designs, my attendance to "Simpler is better", in this regard may well not hold true, or be entirely accurate, I suspect. I also clearly see the logic in the "Hear for yourself" notion... and were I able to jump in the car my weekends would be filled with that activity. Trust me, they certainly would. Such is not the case. 'All roads lead to Roma', or so I've heard. fine. I just don't want to take the 'scenic' route... or as little as possible. yes, until the speakers are sitting in the living room, no one really knows.... dealers ain't big on the idea of lending out speakers too much around here... unless you lay out the full bill... and I ain't by nature or economics able to fade that action... especially in the 4K to 8K retail range... so even in face to speaker comparisons, it's doubtful anyone can truly say that'll work fine in my room....without hauling all their gear in to try things out... and even then perhaps. So some research in advance to cull the herd, seems wise enough a notion to me.
Let's say all the drivers are of equal value in a certain enclosure... the heart of the system then would have to be the crossover, I would think. Like the transmission and brakes in a car. Great motors need those two items to get ya where you want to go. the more closely matched and better they perform, those latter devices are meshed, the better the efficiency and hence performance of the overall system. I would think.
Given all the insights, and debate, if nothing is clearly determined, it remains beneficial and noteable in and of itself, to find out that certain crossover designs are better suited (or not), to particular driver configurations, and evne that notion seems without great substance in determineing a choice solely on that one crossover over another, provides more naturalness and fluidity in development of the signal. for audible re-creation. One factor I overlooked in my haste was to add for three, or four way enclosures. As they are the focus for me. Id really like to have a pair of speakers that do not need subsonic aid but so far, the few Ive found to do that deed are either cost prohibitive, or are lacking elsewhere in sonic reproduction mind you, I dont need perfect just balanced would suffice with any prominence or lean, being set toward the mid and/or lower ranges, though balance is the goal. Which is in keeping with my sonic preferences.
Of all the imformative venues Ive experienced, this one remains an insightful, and dependable one as Ive encountered on my little audio-addict sojourn. And why I prevail upon the experiences of those with far more than I.
Thanks Eldartford, I hope I made it clear enough in my post that I am not making comments of any great authority of my own, just some things I was told and/or picked up. I was simply told that it is harder to do a first order cross over correctly than higher order, if that isn't the case I am fine with that, but it would beg the question, why don't more manufacturers do first order cross overs. (Another "thought", is it possible that schematics for a high order cross over looks more complex, but it is actually harder to get the same result with less parts, therefore in the end the one looks simpiler but the road to the result was just the opposite?)
"However, your comment about having fewer components in the signal path is very valid. IMHO this, rather than phase issues, is the chief advantage of the first order X/O."
Eldartford, i think that you are discounting the merits of 1st order x/o far more than you should. (LOL! you could accuse me of the opposite! Anyway, w/o meaning to take a pot-shot @ you; rather, to have a meaningful discussion...) there is a definite merit to using 1st order x/o circuits in a speaker that has to do w/ better preservation of phase compared to a 2nd, 3rd, 4th & higher order x/o ckts. your statement of 1st order x/o ckts having a phase shift is very true but what you forgot to write was that 1st order x/o ckts are the only ckts that maintain a constant phase over freq. No other higher order x/o ckt has this feature. it is also true that a 4th order x/o ckt yields a 360 degree ph shift, which can be equated to a 0 degree ph shift but the key here is to realize that in the 4th order x/o ckt, the phase shift between tweeter & midrange & woofer is 0 degrees *only* at the x/o frequency. at all other freq above & below the x/o freq, the ph shift amongst these 3 drivers varies i.e. it's not constant. this is *unlike* a 1st order x/o ckt (which maintains a const ph shft above & below the x/o freq). That Rod Elliot paper I provided a link to describes this very well. IMHO, it is this preservation of ph shft across the freq band that makes music thru a 1st order x/o speaker sound far more real than one w/ a higher order x/o.
"I have a hunch that manufacturers who use first order crossovers, often for very good technical reasons, feel vulnerable to accusations that they are looking to save cost, and respond with marketing hype and the suggestion that their crossover design involves some mysterious art."
it is possible that they do cover up w/ some marketing hype. however, i do feel that few people in the audio manuf industry understand how to correctly implement a 1st order x/o speaker. there is much skill needed. IMHO, you might be discounting their talent a bit too much. maybe you have some experiences that lead you to believe that 1st order x/o speakers are all hype? you seem to be jaded? or, is it typical cynicism from an engineer?
"....but it would beg the question, why don't more manufacturers do first order cross overs."
there might be several reasons for this. I can shed light on 1-2 that *I* think are the reasons. it is only quite recently that well-made drivers have become available. i define "well-made drivers" as those that have a wide(r) range of operation such that they can be x/o at reasonably high freq. For example, the 10" Audax woofer in my 1st order speaker is x/o at 350Hz to the midrange but the woofer has a flat response upto nearly 1 octave higher. this has allowed the speaker designer to make a true 1st order x/o speaker 'cuz @ the x/o freq only the electrical network kicks in & the driver roll-off due to its mechanical structure has not yet kicked in. Most drivers in yester years did not have such performance. Thus, they were not true 1st order x/o speakers - @ the x/o freq they had the 6dB/oct roll-off from the electrical netwrk + the 6dB/oct roll-off from the physical driver. so, they were, in effect, 2nd order systems.
2ndly & related to the above reason, it is only very recently that drivers are better able to handle more spurious power. by this I mean that in a 1st order x/o, the roll-off slope is very shallow (6dB/octave) so a considerable power leaks into the adjacent driver (woofer's power into the mid & mid's power into the tweeter). with the advent of better power handling drivers, the speaker designer is better able to make a speaker that can play at reasonably high volumes. Even then, a 1st order x/o speaker cannot play all that loud. For example, the woofer in my speaker compresses at 105dB SPL. Quite loud but way softer than a 4th order x/o speaker of the same physical size & power handling. So, if one wants to play rock at paint-peeling loud volumes, this is not the speaker. Several users do not like this short-coming. the slope of a 4th order x/o is much steeper & the power leaked into adjacent drivers is significantly less.
Aside from this, if you read the Rbischoff thread that I provided a link to, you notice that a 1st order x/o speaker does have to deal w/ "comb" effects i.e. periodic nulls created in the space surrounding the speaker. i believe that every speaker design has to deal w/ this but, it's my understanding that, in 1st order x/o speakers this effect is worse.
Additionally, improper implemented 1st order x/o speakers seem to have very poor vertical dispersion so that if you stand up from your listening seat, the 1st order magic sound is lost. it takes some skill to minimize (or even eliminate) this effect.
Eldartford, while obviously somewhat esoteric I think the original Walsh driver Ohms could be included with ES drivers as being cross over free. As you said (and I completely agree) that cross overs are a necessay evil, even ES drivers have limitations with regards to frequency range at typicaly desired volume levels. On another note when do we seperate mechincal from electrical cross overs?
Bombaywalla...The link you provided looks interesting, and when I have time to spend I will study it. However, I must dispute your suggestion that the phase difference between drivers in higher order X/O does not remain constant at frequencies away from X/O. A second order X/O is basically a series connection of two first order X/O, and what works the first time does also the second time. A Crown professional electronic X/O that I keep around for experiments is 18 dB/oct, and has a comprehensive manual that shows graphs for both amplitude and phase response for various frequency settings. 270 degree phase difference exists at all frequencies (as I would expect).
My main speakers are Magnepanar MG1.6, and the high pass filter is first order. The low pass is second order, and the break frequencies are significantly different. Of course the Maggie "driver" is quite different from the common cone driver, but it all goes to show that a X/O network can be taylored to the characteristics of the drivers used.
I also use an electronic X/O for subwoofer/main, and it is fourth order. In prior systems, where the main speakers were biamped I have had excellent results with fourth order.
Unsound...We don't separate them. The full range advocates don't like to admit that their drivers break up, and emit different frequencies from different parts of the cone, and this constitutes a mechanical filter. If you think that design of an electrical filter is difficult imagine the work it takes to get a mechanical filter right!
Yes single drivers do have a mechanical filter being the driver itself.But there's a bit more to it than that.I think Wayne Parham explains it very well here Electrical filters and Acoustic Filters.Also when it's right ..it's pretty darn good.Martin King and Bob Brines have found a method that works well.Though single drivers..especially mass loaded transmission line models won't play at rock concert levels.What they do within their usable SPLs and frequency range is terrific.One of attributes of their design is minimal impedance and phase angle shifts.The difference can be heard if one were to only take time to listen.The distortion levels are the lowest I've heard in my home and anywhere else for that matter.My Magnepans didn't have the speed of these single drivers with 50 wpc,even with a 600 wpc channel amplifier on Maggies.Bombaywalla
thanks for the links ..this is good stuff!
Apparently, this thread has become but a public forum for a couple folks to correspond... ever hear of email? Your dialouge seems to have gotten off topic some.... with point & counter point rehetoric about personal perspectives... though input is more than appreciated, getting back to the gist of the thread might well serve others, right? ...and not be "Who's right & why" sort of thing. OK?
Blindjim, See your own quote here, not sure but looks like you are fishing and someone put some bait on the line for you to help. And further your title states " Are first order crossovers best?" yet you explain you own 4th order, so you got opinions and reasons thats it.
"What order crossover is in them, first, second, third, etc?"
I believe mine (VR4 JR's), are fourth order.
The thought that comes to my mind is this...What does that matter? Should I care what sort of ordered crossover there is in a speaker? How big or small a part does it play?
At this point I have no answers for the above Q's.... if I could have your thoughts and experiences it would be more than appreciated to shed some light on this currently dimly lit subject..."
havbing found out that with most everything audio, there is a sonic signature of some sort, I felt to inquire as to crossovers. I figured simply to find out about a subject I know little of and hopefully determine some basic traits of the different type networks.
Example... most people will say a certain preamp is 'warm', and another is 'dynamic'. One amp is better suited for this, and another for that... The aim was to decrease the huge number of available speakers out there in terms of possible compatibility or incompatibility, with present and/or future gear.
Like I was sort of expecting to hear something like:
Well, with first order networks I've found they work best with SET amps. or Fourth order does best with Solid state. I've since began to think along the lines of "What did the speaker maker use to voice them with in terms of amplification?" instead of focusing on what sort of crossover is in them... I apologize if it made no sense to anyone else... it did to me... at the time.
I believe I've had mostly 'fourth' order in my previous speakers (B&W), and The Monitor Audio people say they use no caps in their Gold 60's, of which I also had a set... my PC 10.5 Phase Techs I'm not sure about what is in there... 3rd, I think. The Jr's use a 4th. All of these have been paired with 120 wpc to 250 wpc solid state amps of various brands. Never tube amps. My level of experience and/or my ignorance as to system synergy and it's importance along with some poorly put 'professional advice' cost me severely with some past efforts to put together a decent system. I'd as soon forgoe that experince again, if at all possible.... I sought to do that by asking what I believed a simple question. That's all.
I'm likely to stay with solid state amps and tubed preamps. . . and plan to move into either the BAT 600 or CJ P350 later on, with either a BAT, Thor, or CJ preamp. I also will probably get into a pair of speakers other than the VR4 JR's I have now. Something from perhaps VA. Strauss? Being goal oriented, and with fixed disposable income having some idea in place beforehand is comforting to me. hence the question (s).... I've not the resources to simply buy this or that to find out. truth be toled, that process is weairsome and tedious. Let alone expensive. Again, I apologize to misspeake or mislead, or be too grey with the inquirey.