@mijostyn -- Just looked over at your profile, and you have an impressive set-up from what I can assess (haven’t heard it, obviously, but I’m sure it’s sonically extremely capable). You wrote "Sound Labs" being your main ESL’s, but the profile reads Acoustat’s - which is it? A friend of mine have a pair of older Acoustat’s, smaller than yours (can’t remember the model number), and they’re very coherent sounding, transparent and informative. Having a single transducer cover the entire range from 100-20kHz is an impressive, and not least an important feat when done well; being ESL’s I can only imagine that it is. Moreover being a line source (as such) from floor to ceiling adds to their traits. Personally and over time I’ve never been fully convinced or taken the type of presentation from the line sources I’ve heard, but as executed in your case, with subs augmentation and the ESL’s relieved below 100Hz to boot, I may feel differently about it. You don’t shy away from cone area with the subs either, and with lots of power at hand from your QSC’s bodes well for headroom and clean bass. Have you tried spreading out your subs DBA-style? Not meant as an advocation of mine, but just curious what you’ve come to find here, in case. I can certainly relate to where you’re getting at with your set-up imagining a large, enveloping and coherent sound field that’s fairly uninhibited LF-wise as well. It’s not at all unlike what I’m after, though quite obviously very differently executed. @johnk -- Community made the best horn designs even today we haven’t equaled what they offered during the 1970s. Their multi cells are by far the most advanced on earth the leviathan and the radials all not bettered by modern designs. I have been beta testing for a few companies they know I have many horn types to use the horns they made to go with there new designs are just based on older designs but are smaller. So while it is possible to design better horns today we don’t because of the size and costs to build them. It’s the recurring roadblock for sound reproduction in a home environment: size. JMLC horns (with the proper calculated horn profiles, that aren’t mostly used) are great, I find, and don’t skimp on size. The upcoming bigger EV horns of mine (HP9040) mayn’t dance with the best, but I’d wager they bring about advantages (compared to smaller, more modern horns) precisely because of their size and controlling directivity as low as they do. Getting a closer coverage pattern match over the cross-over range arguably is one of the "macro parameters," and being successful seeking out and attaining others as well is what it’s about, basically - to me, at least. Size restrictions keep one from hitting many of said parameters, but more than cost considerations it appears size itself (and the change in design narrative) is the primary obstacle. |
My reply is intended to illustrate why & how some high performance speakers are purposely designed knowing that they will have to be low in efficiency because of the laws of physics and engineering. Mini-monitors, like the sealed BBC LS3/5a's and the rear vented KEF LS-50's which have fairly good bass, superb mids & highs but low overall efficiency (82db to 84db) have obviously earned a prominent place in the market. While higher efficiency spkrs are the ideal it it's impossible to achieve both extended bass & high efficiency is small cabinets. Therefore, if you want a mini monitor to achieve bass the efficiency will have to be limited to about 82db to 85db. The smaller the speaker box, the lower the efficiency must be to avoid sounding thin. The laws of physics & engineering just can't be ignored. But there are tricks to make it possible for small woofers to perform well in both the bass and midrange in small enclosures. The 1st is the use of small magnets which raises a woofer's Total Q factor(QTS) which partly determines the bass output consistent with Theile-Small equations. The 2nd trick is to increase the compliance of the woofer surround which lowers the woofer's resonance frequency. A 3rd way is to select high mass cones effectively raising the QTS and lowering the free air resonance frequency. A 4th method is to use crossovers that simultaneously tame the mid frequencies of the woofer so that they don't drown out the woofer's bass output and at the same time use woofer crossover inductors (coils) with a high enough measured DC resistance to raise the woofer's effective QTS. A 5th method in sealed boxes that accentuates bass but lowers efficiency is to judiciosly overstuff the cabinets with absorbent material eg fiberglas or polyester pillow stuffing which makes the woofer behave as if it's in a much larger box. The stuffing amount can be adjusted to change the QTC (the box's QT) ideally between ,707 and 1.0. A final thought...complex crossovers can be very helpful in compensating for imperfect woofers, tweeters, & mids but they lower overall efficiency and often tamp down dynamics. Obviously there's lots to consider.
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My reply is intended to illustrate why & how some high performance speakers are purposely designed knowing that they will have to be low in efficiency because of the laws of physics and engineering. Mini-monitors, like the sealed BBC LS3/5a's and the rear vented KEF LS-50's which have fairly good bass, superb mids & highs but low overall efficiency (82db to 84db) have obviously earned a prominent place in the market. While higher efficiency spkrs are the ideal it it's impossible to achieve both extended bass & high efficiency is small cabinets. Therefore, if you want a mini monitor to achieve bass the efficiency will have to be limited to about 82db to 85db. The smaller the speaker box, the lower the efficiency must be to avoid sounding thin. The laws of physics & engineering just can't be ignored. But there are tricks to make it possible for small woofers to perform well in both the bass and midrange in small enclosures. The 1st is the use of small magnets which raises a woofer's Total Q factor(Qts) which partly determines the bass output consistent with Thiele-Small parameters. The 2nd trick is to increase the compliance of the woofer surround which lowers the woofer's resonance frequency. A 3rd way is to select high mass cones effectively raising the Qts and lowering the free air resonance frequency. A 4th method is to use crossovers that simultaneously tame the mid frequencies of the woofer so that they don't drown out the woofer's bass output and at the same time use woofer crossover inductors (coils) with a high enough measured DC resistance to raise the woofer's effective Qts. A 5th method in sealed boxes that accentuates bass but lowers efficiency is to judiciosly overstuff the cabinets with absorbent material eg fiberglas or polyester pillow stuffing which makes the woofer behave as if it's in a much larger box. The stuffing amount can be adjusted to change the Qtc (the box's Qt) ideally between .707 and 1.0. A final thought...complex crossovers can be very helpful in compensating for imperfect woofers, tweeters, & mids but they lower overall efficiency and often tamp down dynamics. Obviously there's lots to consider.
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Hi @atmasphere ,
There are a lot of examples when amplifier has mixed SE and PP stages.
For example some SET amplifiers have first stage SRPP and PP amplifiers have SE first stage before phase spliter.
Another example - SE preamp and PP amplifiers.
Do all these amplithis have a prominent 5th harmonic in addition to a 2nd and a 3rd ?
Regards,
Alex. |
Great conversation. I think some of you would really be interested in JTR speakers. They were mentioned earlier in the thread. JTR does pro audio as well as some high sensitivity home speakers and subwoofers. I am looking forward to hearing them because of the great reviews I have read. |
There are a lot of examples when amplifier has mixed SE and PP stages.
For example some SET amplifiers have first stage SRPP and PP amplifiers have SE first stage before phase spliter.
Another example - SE preamp and PP amplifiers.
Do all these amplithis have a prominent 5th harmonic in addition to a 2nd and a 3rd ? In P-P amps what is concerning is what circuits are in the feedback loop. They will affect which harmonics have more prominence. IOW the topology affects the distortion signature. IMO a single-ended preamp can work alright with a balanced amp, but I'm not sure that is what you are asking as P-P amps cover quite a range of circuits! |
Large size costs more in all ways more to build, ship, store more materials used more finish applied. It's just the way it is. Size is one of the most costly parts of horns. |
Quad 57's still sound more like real music than most of today's overpriced offerings! I own two pairs! |
And still a formidable contender in the small box category is the BBC LS3/5A! I have a pair of Rogers 11 ohm's. |
a systems engineering approach should always compare the output with the input, including impulse response. Sure a hyper well executed high efficiency driver using best available materials, engineering, machining, etc are expensive. I think any reputable end speaker company designing own drivers, even semi custom w Scanspeak, are similar $$$$$. Some of those take into consideration that output is not a measure of quality.
I also believe, no designer should ignore ear brain. Many just sell distortion we like. Flavorizers.....
sure, the holy grail is low mass, breakup far from the passband, pistonic, with super high strength motors and high duty cycle....nothing has changed....
also, as an ESL owner, I think about the sonic impact of transformers and edge clamping distortion as well as energy storage in the panel....ain’t no free lunch
glad the conversation has returned to civility.... |
No free lunches indeed. There are those who'd like to sell the idea that big means much more expensive, but to them boutique, often vintage drivers with field coil or alnico magnets in addition to luxury, hand-build finishes is the only validating entry into the high efficiency arena. Their (affiliated) business, obviously, but NOT representative of what's possible with high efficiency and large size at more reasonable prices that can as well produce great sound.
The real non-free lunch here is size (and the product segment typically associated with that), as we're seeing considerable expense being shelled out already for a speaker package not much larger than a meager shoebox. Sound is physics, meaning displacement and efficiency is irreplaceable as that which accommodates truer dynamic envelope, low distortion and ease - core parameters into what is perceived authentic as a live event, yet they're wildly neglected for above reasons; not price, but size predominantly and the product narrative that follows here. Last but not least: live sound mayn't be that big of a draw after all.. |
Clearthinker, good questions, great thread!You brought up all the eternal questions in audio - high power vs low power and high vs low efficiency, and of course, cost issues. Looking at the average audio product, 1 in 10 sounds very good, while the rest is mediocre to bad. (Due to flaws, or more frequently, due to equipment mismatching. Even for low efficiency speakers, you have to hear about 20 to find one great sounding. The same is true for high efficiency speakers, and given that it's rare to hear even a single one of those, and you need to hear 20 systems with them to have a comparable basis to low efficiency speakers. Most people do not get to that point, and as there's a minuscule chance that one trips onto a great sounding one right at the first try, the automatic assumption is that H.eff speakers are inferior.
The true difference between low and H.eff speakers is that H.eff speakers couple cone movement to the air much better, hence they translate much more of the audio signal to sound. As a result, you hear much more dynamic resolution, and you also hear much more of any defects the system has. It's not just the speakers issues are magnified with high sensitivity, but also the rest of the audio chain is forced to come out of hiding, and their flaws are exposed. That's why slid state amps sound generally quite bad or at least disappointing with them. Indeed, most tube amps have issues as well, but a good tube amp can be built in a reasonable budget that will sound good, while I have yet to hear a solid state amp that sounds even remotely acceptable once efficiency goes beyond 100dB/Wm.
The issues with H.eff were not just affordability but availability as well. The retailer can stock half a dozen to a dozen plus speakers in the same space that a single pair of H.eff speakers require. When a store owner can stock 5 pairs of speakers total, he's not going to stay in business. Also, while nowdays the price range for H.eff drivers went down, in the 50s-60s when the low efficiency speakers changed the scene the driver costs for H.eff drivers were much much higher than low eff drivers, and the relative cost of even a simple audio system rivaled that of a motor bike or a car, so the only choice really was the low efficiency version. Plus, who wants to give up half the living room space to a stereo system when you can get one that can be shoved onto the shelves? Also, you cannot sell the weak amps and sources with H.eff speakers as any deficiency will be glaring at you, so that's another key factor that limits H.eff and favors low eff speakers.
Class D for the low end is a very enticing solution, and is a fantastic compromise if you want H.eff midrange and top end. Yet, the stark difference in sensitivity between the two parts of the spectrum will come and bite our donkeys (or, asses). Your ears will come to realize after a while that there is a huge disconnect, and you will loose interest in the sound. To me, one of the biggest advantages of high efficiency is the efficient bass. It sounds first as if there was lower bass extension, because you are not getting that "pressurized" feeling that your head is about to explode with the sound pressure. However, you will notice that the sound is not a porcelain muppet freakshow anymore with angry goblins kicking your seat, but you are hearing much more natural presentation - base will sound breathing and alive, and when you turn the volume down the soundstage does not collapse.Amplifier power: for 100dB/Wm efficiency you need 60 milliwatts for a VERY LOUD volume, and you still have tremendous headroom even when using a 500milliW (half a W) amplifier. The quiet passages will play at microwatt levels - that is a few millionth of a watt! So, if you have an amp that excels at 6000W that;s not necessarily going to be a virtue here, as does it also excel at a millionth of a watt?
I have a youtube channel dedicated to audiophile education, (Real World Audio), and most of my videos are about these subjects, distilling my 20+ years of experience building & designing speakers and amplifiers.
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Thanks realworld.
Congratulations on your perceptive first post here. Keep 'em coming!
I note this thread is well into its 4th page.
You mention equipment mismatching. How true!
In another recent thread dealing with: What's the most important element in getting good SQ, nobody had mentioned this in 40 posts, so I chimed in. I say it may be the MOST important single element. Certainly if you get it wrong.
But I am not in agreement with a generalised preference for H.eff speakers and tube amps. My Martin Logan CLXs are 87dB so fairly inefficient. But 400w of Krell Class A (real 1980s Class A, not today's pseudo stuff) does the trick. With +12dB on my pre-amp it's actually very loud at a quarter up. I have no doubt that some big tube monoblocs would also do a good job.
My speakers are big but panels. As you say, to get this kind of SQ and H.eff I would need very big speakers indeed, probably with very high associated cost some of which I would recoup on smaller amplifiers and electricity bills. |
Realworldaudio,
While I agree with some of what you wrote, ie that high eff speakers will reveal more amp issues, I can't agree with much else. They won't reveal any more of the signal chain than the amp.
I find other statements mainly conjecture based on implementation and nothing about hi/low eff. Low efficiency speakers are not more dynamic and their bass is not more natural. If you are running SE tube, good chance you have some frequency anomalies you like and those anomalies can be conducive to low level listening.
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also, as an ESL owner, I think about the sonic impact of
transformers and edge clamping distortion as well as energy storage in
the panel....ain’t no free lunch Don't forget flexing and subtle mechanical movement of the panel :-). Good post tomic601. Lots of hand waving but at the end of the day you are either having accurate, low distortion movement, no matter the efficiency and amp, or you are not. |
I'm completely agreed with @realworldaudio.
High sensitivity speakers give much more real music reproduction.
The low sensitive speakers, even big and expensive like Wilson Audio, Dynaudio,... have artificial bass reproduction and sound not alive.
Electrostatic speakers have good microdynamics and sound more alive. But they have issue with macrodynamics and bass.
Regards,
Alex. |
Thank you clearthinker for your welcome! I agree with your
perception, equipment matching is the essence of a good system. Essentially,
any amplifier topology or speakers design can bring us to musical bliss when
every element is in perfect synergy. That takes long experimentation, decades
of trying combinations out, and ultimately sheer luck on stumbling onto it.
After much experimentation we know more, and can hit synergy more often. I do
not hold any technology superior to any other, each have their own compromises,
and cater for different experience.
In my audio journey my experience is that the major cost
element is the time and work I put in it. If you are willing to build the
cabinets and crossover, then high efficiency can be built for 6K$ or less.
(Sure, a comparable commercial design would be around 35-60K$, but then there’s
no need for 10,000 hours invested into R&D.) So, compared to even meager
speakers costing today at 10K$, and SOTA around 250K$+, I think that cost is
not an issue anymore to high efficiency for a dedicated serious DIYer, who had serious
mentors and experience.
To audio2design: I respect where you are coming from, and
all of us have different sets of experiences. Thus, I will refrain from holding my
experience base superior to yours, and I am open to new experiences. I have heard
and seen enough not to pass judgment blindly, and to find treasures at corners
where I would never suspect them. That’s the point of this thread, to open our
minds to new possibilities. When I wrote about the low level listening with SE,
I wanted to convey that it can reproduce music when played at soft level, while
complex big amps fall into anemia (crap out) when played at the same soft volume. The SE
amp with the H.eff speakers can play distortion free up to 100dB/m levels. While my SE amp has super low,
less than 1W output into the 16R H.eff speakers, the output transformers are
rated at 25W, and the power supply is build to deliver enough for 300W output.
Most SE amps fail at rating the PS and the OPT close to the output level, (and fail even more miserably at supplying a well filtered quiet B+) and
thus operate close to transformer saturation, starved PSU and lack of low level detail. When built right, the 1W amp sounds as dynamic and strong and distortion
free as an absolutely massive amp would sound. Indeed, you are right, most of what I said
depends on implementation. Actually, everything depends on implementation, so I’m
glad we can agree. There’s no single immutable point, everything is just a
generalization, as basically not a single parameter is kept constant for all
equipment installations. I was trying to rack my brains to come up with the
difference between H.eff and L.eff that would be a constant. I could think of
two aspects, which I found immutable regardless of setup conditions. One is
that with H.eff the concept of volume becomes obsolete: adding volume gives the
feel of greater dynamic range, but I do not get the impression that the average
sound volume is getting significantly louder. It’s the dynamic range that
expands. Still, this can depend on the system, and if preamp is not up to spec,
you might have different experience. My second observation is more versatile:
H.eff allows you access to EVERY record. Labels and pressings one would never
think as capable of providing music experience become playable and at shockingly
good quality. Not as good as a perfect recording, but they allow you to ENJOY
them, and they will sound much better than you ever heard them on any system, while on L.eff they are intolerable.
Getting back to the amp issue: laws of physics dictate that even
if we had a perfect way to amplify signals, then the amplification to 1000W
introduces x1000 times more entropic distortion than amplification to 1W, and
there is no mechanism to get back that loss. As technologies are imperfect, the
actual distortions with increasing power are even greater. My experience showed
me that tube amps have a much, much greater potential to present microdynamics, harmonic and spatial content. Not the 100+W ones, the small ones. The higher the power
the more the intricacies fall apart, and a big fat 200W tube amp just becomes a
wannabee solid state amp.
To me, SS amps sound inhuman, with extremely few exceptions.
Sure, lots of power and control, but lack of harmonic riches and low level
detail. I agree, they sound as perfect PA amps, and that’s king when one is
going for the ultimate amplified sound. My comparison is to live, unamplified classical
instruments. Tubes do a much better job for me to portray the message that the acoustical
instruments portray. I understand that systems preferences ultimately boil down to our listening habits, subjective preferences, and how far we came on our audio journey. Thus, such debates will never come to a closure. I hope that everyone find his and her source of joy. |
