Sorry, does this belong in “tech talk?”
Is Speaker design evolution stagnant
Based on what I read from speaker manufacturers, many use the same drivers but apply different crossover philosophies to achieve a particular sound.
My simplistic understanding is that while limiting the range of high or low signals , the remaining signal is corrupted ( phase inversions, roll off, etc.. ).
With today’s technology, why aren’t more speaker manufacturers using active crossovers to be connected after the preamp and sending exact spectrum signals separately to be amplified to each driver. That would Eliminate all electronics inside the speaker cabinet except the drivers. Each driver gets fed only the signal that it works best at. No out of phase, half phase, quarter phase issues, no phase angle issues. 100% of the power goes to each driver without limiters to scale it back. I think Bryston Model T Actives is designed this way ( don’t work for them and not pushing any product). Am I looking at it too simply? Do electronic crossover play havoc on signals the way inductors and capacitors do?
Some speaker manufacturers have gone half way with built in woofer amps ( Vaughn?)
Of course you would need a 3 channel amp for each side ( based on W/M/T config) or some variable of mono amps, whatever.
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Some manufactures and designers are using techniques like you describe. Linn has been using active (Aktiv) systems for decades. All of Meridian’s speakers/systems use digital active processing. Solutions such as MiniDSP allow people to implement digital active crossovers, time alignment, parametric equalization and room correction. Passive crossovers have become a mature technology and technique, and the amplifier watts to power them have become more affordable. Both passive and active designs can offer great sound, but more and more companies are starting to utilize active systems and digital processing, which I think will continue to grow in the future. |
Given the ever dropping cost of computer technology and ever increasing processing capabilities , this is what I imagine will happen IF there is good money to be made : a few companies will pop up to manufacture active crossovers that can be used with any speaker along with an application that can be operated from a computer ( I-pad, I-phone, laptop....) and utilize a Bluetooth microphone. It will allow you to generate the full spectrum of sound, take readings, give you graphs and allow you to equalize your speakers on the fly. i know some form of this exists, but I am talking user friendly software with real time results on a graph. like my son’s simple clip on guitar tuner, 3 led lights that light up to show you whether to tighten or loosen the string to be in tune. As as far as the cost, I think manufacturers will jump on board if they can sell more amps...home theater setups get people to buy 5-7-9 speakers instead of 2. that seemed to catch on. |
OP: You need to go away. Seriously. You need to go away from this forum and go build your own active speakers. :) Join us over in DIYAudio or the Parts Express forums. You'd learn a huge amount, build just what you like for pennies on the dollar and be much better informed than you'll gain from hanging out in open forums. Good luck, Erik |
Given the choice, many speaker manufacturers would probably say that a every speaker should be built with its own external crossover and dedicated amplifiers, optimized for each driver. Every parameter would be within the designer's control. But the audiophile marketplace just doesn't accept that whole integrated philosophy. People want to mix and match speakers, cables, amplifiers, etc. So speaker manufacturers build what they think people want to buy. |
I agree that active crossovers are excellent. Yes you need more amp channels. But multi-channel amps are readily available. Take Erik's advice and learn more about this. My suggestion is to check out Linkwitz Labs website. Linkwitz also eliminates the box. His speakers are stunning IMHO and you can build a pair! |
GT Audio Works produces their own planar drivers without any crossover on their main mid range panel which is about 6 feet tall. They have won numerous best of shows and unlike other planar magnetic drivers that have a plasticky sound due to the fact is a single membrane these particular speakers have a quasi membrane which is bonded to the mylar which causes no resonances. The technology goes on and on with the speakers such as a frame with in frame construction to reduce any vibration resonances, the use of pure copper traces versus the cheap and inferior aluminum which is not as good as an electrical conductor as copper. Another important fact is is that the speakers have a lifetime warranty and have a lifetime upgradability. These are also the only speakers that are being produced with cryogenically treated drivers |
I would not say development is stagnant, maybe just turning in a direction away from whats been done for years in one form or another to a new direction fueled by new materials and theories. Back in the infancy of speaker development, Kellog and Rice of Bell Labs patented a new speaker technology the electrostatic speaker, it used stretched pig intestines applied with gold leaf to hold a static charge as a diaphragm material, obviously it had its drawbacks !! Mylar, the diaphragm material needed to make this tech possible was still 18 years away. Same holds true today.new materials and applications will open up new possibilities. For instance, check out this video https://youtu.be/HGOt3JhrUs0 Graphene can be exited and caused to radiate sound by beams of light modulated by a music signal. Cool !! Greg |
There was also work with ultrasonic transducers which vibrate the air at frequencies the ear can hear with very directional properties. It could lead to music aimed at you like a parabolic dish which only you would hear, like headphones but nothing on your head. https://youtu.be/4eZVF1ouTT4 https://youtu.be/hmNzf9ztnAk Greg |
Erik, so tempting to build my own, but I have to admit......I’m afraid. So much to learn. Before I make a choice of any component, I may end up looking at all the alternatives to make sure I make the best choice. I am not afraid that everything on paper looks good but the actual audio result may stink. I can live with the journey and failure, just don’t know if I am up for the amount of learning work involved to understand theory and apply math. i really am not at the semi engineer level that many of you kind posters are. But I will look at the other forums and see if I can follow. jack |
Greg, fascinating technologies, Really fun stuff. Great practical applications. I think plasma speakers are pretty cool too. Faxer, in the 70’s I saw foam flat panel speakers. They sounded eh...ok at low volume. The beauty is , as you stated - single driver so no crossover. But if you pumped more power into them they would catch on fire. |
Jack, GR Research offers a number of speaker kits that are not too difficult for a 1st time DIYer. Check out the website. By the way, the OB/Dipole subs found in some of the GT Audio Works speakers (mentioned above by faxer) are actually a design/product made in a joint effort between Danny Richie of GR Research and Brian Ding of Rythmik Audio. Fantastic subs! |
One more time. Here is a link to Madisound for the Linkwitz LXmini speaker kit. There are online videos from folks who have built these. Active DSP crossover w/ Linkwitz design genius offer great, no, GREAT sound. Kit is about $530, You assemble and paint. Check it out. I have the early version and love them. https://www.madisoundspeakerstore.com/2-way-speaker-kits/lxmini-linkwitz-lab-speaker-kit-pair/#tab-3 |
All speakers are build practical the same :tweeter, mid- and bassspeaker. Now there is one exeption: the Ilumnia Magister, build by two brothers in Belgium. Those 2 boys worked for 7 years on it. It is the first speaker in the world with a floating Crone driver on a magnetic field. It’s 99,7% linear/always pure sound, regardless of noise level or dynamics. Theorie slogan is: Less is more. This patented and progressive loudspeakertechnology gives a new dimension to high fidelity. No energy absorption: 100% preservation of th signal down to the smallest details. No unwanted resonances and distortion caused by spider and driver. I have them at home,and i can say: I never heard such a pure and detailed sound. High-,Mid,and low in harmony. You can see them on the website: ilumnia.be. Now they are buiding a Monitorspeakers. |
A bit of history, if you don't mind: In the mid-1970's one could purchase a combo-effort on the part of two of the premier manufacturers. Magnepan's inventor Jim Winey and Audio Research's inventor Bill Johnson got together--whether Wendell had anything to do with it is moot--and developed a tri-amped system that used an external (tube) crossover. The Typmani speakers were in three parts...kind of what Mr. Winey's son has gone back to recently, with superb results...and they were driven by three+ (you could bridge the amps and run 6 if you wanted to) Audio Research amplifiers run through an Audio Research SP-3 pre-amp. The amps were of the D-76(A) vintage, which was then doubled into the D-150--still an awesome amp all these years later. The crossovers were both passive (PC) and active (EC-tube), and one could select a number of ways to set this up. More importantly, HOW DID IT SOUND?? All that technology is fine, but if it does not sound like a live concert, or as close as possible to one, then it is of little value. The good news is that the SOUNDED AWESOME. Set-up properly in a good room, this was the ultimate in those days. Today, I would guess that the new Magnepan 3-part speaker set driven by quality amps is probably somewhat better as the technologies of all these components has improved since the mid-1970's. In any case, it sounds better than any box speaker system, so I don't think speaker design is in the tank today. Most designers use conventional drivers, but I constantly see engineers trying different materials, etc., to get the accurate sound they are seeking. Too bad that Magnepan found a way to do it better than cone or electrostatic designers have so far...but that doesn't mean engineers are not hard at work looking for the "next big thing." |
Jack, There are many ways to get into it, but in my experience it has been very rewarding to go active and take the learning curve. I echo what Erik suggested about diyaudio (multi-way forum). I started my journey 4-5 years ago. I had a great preamp (Lamm LL2 deluxe) and loved it, but thought a system optimized to do one thing very well would be better, for a given amount spent, than a system attempting to do several sources as good as possible. I bought a multichannel DAC, took the Lamm out, built an "audiophile" computer to be my only front end, and implemented active crossovers between my subs and mains. The tube amp was happy not attempting to reproduce below 80Hz, and so were the B&W 804 speakers. Sound improved. Then I purchased "class-D" amp kits from Hypex, assembled, and now have those 400W driving each B&W bass section. So I removed the passive crossover and have the Hypex directly connected to the woofers, running from 70 to 350Hz. For now I still have my McIntosh tube amp driving the midrange and tweeter section, where the passive xo between them is still in place. So it's a 3-way active. In the process I learnt a lot in many aspects. I am now working on a pair of DIY 4-ways, fully active, to replace the B&W. I really love tubes, and DIY active allows to design to maximize the benefit. For example I want to use SET for the mid and treble sections and SETs are constant voltage sources so high and constant impedance speaker is a real benefit for them...so that narrows it down for me pretty good. I belive conditions have matured to go into this direction. Digital signal processing is enabling stuff unheard of some years ago. Low power Class A amps aren't very expensive these days (SETs or Nelson Pass' First Watt, for example), class D amps of high power and good enough performance for bass are cheap these days, professional speaker drivers are pretty good and a lot cheaper than exotic audiophile stuff (which I reckon I also like). A Rythimk subwoofer kit is cheap. You can build a 3 or 4-way system that will sound super. There is also a lot to be gained with good box (or lack of) design practices - things that tend to be too labor intensive for manufacturers to adopt). It's been a rewarding experience for me. The big trade off is the time I've spent, and will continue to spend. But that's part of the fun for me. |
Loudspeaker design evolution most certainly stagnated. Precious little has moved forward since Y2K. We've seen some improvement in drivers, but mostly in cabinetry, as that is where the talents of today's builders lie. Most of the reason is the designers who either understood the art and science or possessed the intellect toward that have left us. Look to the designs of the previous two generations, you find radically more innovation, and the work of these folks still shines |
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@kosst_amojan absolute no necessary spend huge amount the money if you use 3 way electronic crossover. You can use 2 amps for bass and midbass non expensive class D or class AB , but for mids and high absolutely necessary use high end amps, and basically is much more less money because you need the high end amps much more less power then use one high end amp for all 3 drivers ,like convention 3 way speakers with passive crossover design. Actually you can use 2 big power class D and one low power SAT tube amp. But is very hard and almost impossible made right balance . You have to use measuring microphone and computer program like RTA |
it Seems to me that the flexibility and cost saving to use class D amps for the woofer and AB amps for mid/tweeter is another positive reason speaker manufacturers should be evolving toward targeted amplification of drivers. so I guess the point Bache makes that once you do this you have to strike the righ balance - that is the weak link in the chain, or the hard part to achieve |
Jack, A significant point Bache made and I neglected to mention is the need for measurement. This means a mic and learning how to do it. USB mics are easier to implent but not as good as the internally do analog to digital conversion with a clock that is different from your DAC. But an easy way to get going, which in my mind is most important. Incremental improvements rather than radical changes. The learning curve for radical changes is even steeper than the upfront cost and likely to frustrate. |
@Jacksky Yes , i already know what i am talking about, i made semipowered LS Bache audio-002 with build in 2 amps . one for low base 25-150Hz (adjustable) and one classAB 100-700HZ (fixed) customer need just one external low power AMP. sound pressure was balanced (using RTA) sound so good , so need to be listen |
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kssst_amojan, I dont want to argue. You are DIY guy and build and rebuild for own use, i hope you sound as perfect as you tell us. is no secret we use high quality amp module from Hypex , it not such expensive and no chip, we have account and get good price. you see on market now plenty accembled amps based on Hypex M-core Some people like it ,some not, but without doubt is best choice to amplified 25-700 hz, The quality , damping is excellent amd price for all parts no more $700-800 per speakers ( no labor cost) FOR mids and high my customers using low power class A (tub or solid state) My personal preference is Pathos double TT 20 Watt per channel. See my http://bacheaudio.com/bache-audio-002ab-loudspeakers-v2-stereotimes-com/ http://bacheaudio.com/6moons-audioreviews-bache-audio-002ab/ |
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Kosst, What you describe is true, sometimes. As usual it depends on implementation. Active digital xo aren't that complicated to implement and can solve the issues you describe if done right. At a fraction if the cost of passive. But the system has to be designed to work that way - not just the xo. Why this isn't used more frequently? The learning curve is steep. It's a lot more involved. You need to be able to measure. It's a lot simpler to connect an amp with a pair of wires to the speaker, play music and call it a day. |
Based on what I read from speaker manufacturers, many use the same drivers but apply different crossover philosophies to achieve a particular sound. My simplistic understanding is that while limiting the range of high or low signals , the remaining signal is corrupted ( phase inversions, roll off, etc.. ). ~~~~~~~~~~~~~~~~~~~~~~~~ I can see where you are goping with this *stagnant* idea Yes agree. Wayyy back when. Speakers for hollywood's early days were FC/Wide banders. ,,fast forward,,, along came xover things. WE all fell for them. Sure EV < Zeinth, SupraVox, Jensen a few others had some nice speakers with wide banders,, but the labs had to go where the money was, rock N rollers wanted the boxes with xovers. A few were allright, most sound like garbage. Some folks like pannels/stats, others horns, others xover box types. While others are showing interest in the new wide band designs. New = past 10 years. I am of the new WBer camp. And i've decided to invent/design/experiement with my own ideas of what is possible/not possible with these WBers. Thing is don't need xovers, as i have no exp in designing xovers. Stats/panels pretty much are the same past 30 years. same issues Horns, again, pretty much same issues as tyhe early days. Xover types, same old, same old. Great Rock N roll speakers. There are the new concentric types that are making a hit, like ZU's, This design although a good alternative to WBers, just ain't my cup of tea. Everyone is going to stay with his own preference of speaker. A few might have several designs in their collection, but most really are just happy with the one selected design. I have found some use for the xover widwoofer and a tweeter as sort of supporting roles in the operatic casting. The main tenor and soprano are the WBers. W18's + tweet are welcomed on stage as long as both are well behaved and don't voice grouchy/colored. Midwoofers have to be neutral like the WBers and tweets have to be 91/92db. I note Seas has a dedicated midrange, which may substitue for a WBers midrange magic, but my tech gave 2 thumbs down on that idea for a 3 way. After this idea, I completely abandoned xover types a a main voice in my speaker set up. So like yeah to answer your Q. I ain't waiting around for Seas to develope a breakthough in a midrange magical speaker or a super WBer. Seas put all their money in the xover types, and never gave a hoot about the WBer design. The Exotic is wayyyy over priced and its a older design. Too old. The other with the grey cone is trash garbage. Inspite of the YTer tech geek with all his measurements giving 2 thumbs up to that Full range. I sent them back to Madisound after a 15 minute testing , Everyone here is going to gravitate towards his speaker design by choice. xover fan'atics ain;'t going to dump xover box designs and jump on the WBer band wagon. But at least, I am now awake and aware these WBers do exist and do make some nice musical sounds. There are countless possibilities to put together something really nice with whats already out there. You just have to get creative. |
Loudspeaker design could be said to have stagnated as there doesn't appear to be much difference between the boxes of the 1960s and the boxes of the 2020s. Ok, the boxes might be smaller and slimmer, but they're still usually cone/dome drivers in boxes. The age old problem is that in order to sell in viable numbers they will have to be domestically acceptable. Given that maybe we could say that development has been rather constrained by circumstances rather than stagnating by lack of effort or will? Perhaps the only real significant development has been the emergence of active designsalong with the increasing integration of subwoofers. These days virtually every single professional audio monitor has its own built-in amplifier. The main differences cited are usually accuracy (by far in favour of pro designs!) and the prevalence of near field designs in the professional world. Perhaps there is some convergence between these two approaches, as there should be with the use of sophisticated measurements available nowadays, but few professionals would consider using a domestic loudspeaker for their work. [Not even the truly iconoclastic Quad ESL]. The reverse might be said for many audiophiles, but that situation might change with the emergence of more measurement based sites like ASR. Perhaps as a direct consequence we might see more consumers gravitating towards pro designs in future? Nevertheless such sites still favour cone and dome drivers in boxes. So perhaps those early loudspeaker pioneers were on the right track after all? |
So perhaps those early loudspeaker pioneers were on the right track after all?
~~~~~~~~~~~~~~~~~~~~~ Actually the early pioneers were the Chicago and Berlin FC WBers. Here is my fav video of the 1929 Colotura FC WBer There are many xover box types of today that can't match this midrange quality. This is the Gold Standard where all speakers are judged. Put the Wilson's, Tektons, ZU's, next to this 1929 Colotura in midrange/voice. https://www.youtube.com/watch?v=Qrqv5nOjLuw |
