Please pardon the lengthily reply: You asked what I want out of a speaker system. But to answer that can you please confirm something I should know first: Are many speakers systems substantially better at reproducing certain types of music than other types?
It was partly based on this presumption that I’ve been planning to build two different speaker systems: One for my living room and another for a spare bedroom (questions for the latter at another time).
Living room system: To play soundtracks (i.e. John Barry, John Williams, Dominic Frontiere, Bernard Hermann, Elmer Bernstein, et al), orchestral pop (loads of examples from my collection that don’t come to mind at this hour, except for some Burt Bacharach. Brian Wilson’s “Pet Sounds” album and some of his early Phil Spectoresque arrangements), 60s and 80s Herb Alpert, Jazz (McCoy Tyner, Harold Maburn, Sergio Mendes, 1966-69 and his “Ye-Me-Le”), some well recorded soft to mildly hard and psychedelic rock and some operatic vocalists (i.e. Thomas Quasthoff).
That said, and as I’ve often mentioned before, even in a fairly typical sized living room like mine, my ears can’t take high SPLs. Besides, my First Watt J2 and F4 amps are each only 25wpc (though the F4 does 40wpc into 4 ohms). So even though the drivers I hope to end up with (above the 416s) are quite sensitive, big SPLs are (happily) not my thing-just as long as the drivers can still handle the dynamics of the above orchestral stuff.
Therefore, I think there seems to be no question that as alnicos are all about tone- …….“shimmering and vivid tone”, as you say in post #12453-the 416 is a perfect choice in a system to play all of the above music. Furthermore, and perhaps even more so with the 416s in Gary’s cabinets, “……tone and spatial qualities usually go hand in hand”. So, if a pair of Gary’s can at least equal or better the spatial character of the 7.1 system you mentioned, then it looks like the 416s are a shoe-in for the music I’ll play in my living room system.
So the system will have a pair of Gary’s Altec 416s and Rythmik subs that Jim Salk is nearly done building for me. However, the BIG question is what goes above the 416s??
As we’ve both been wowed by what electrostats can do (given their very real limitations), I’m strongly considering a pair of SoundLab’s custom HF/MF range ESL drivers for above the 416s. Roger West says he’s owned Altec horn systems and believes that his ESLs’ dispersion patterns should complement that of the 416s reasonably well. Each left & right ESL drivers are comprise two 5” panels fitted with a special “lens” fitted to them (not really a waveguide he said). The drivers are all used in these speakers SOUND LAB However, as the ESLs only do down to 950Hz, Roger cautions that the ESLs and the 416s need to be crossed very close to 1kHz. He recommends a 2nd order filter, which should be no problem implementing with my First Watt B4 active crossover.
That said, I presume that using ESLs above the 416 for a two-way system and my subs would still not be a good way to go for playing mostly orchestral soundtracks, orchestral pop and mild to slightly harder rock?
So if no to both these ESLs and the SEAS T35 tweeter for above the 416s, then what about a particular RAAL ribbon model that you might recommend-also without a dedicated midrange driver-above the 416s? If yes, please suggest one from here https://www.madisoundspeakerstore.com/index.php?p=catalog&mode=search&search_in=all&search_str=raal
However, if a RAAL ribbon/Altec 416 two-way solution won’t work either, then what about passively crossing a RAAL ribbon with a Tone Tubby alnico? Red Alnico If yes, would I do well with the 12”-which you had measured and played in an open baffle-or the 10”, also in an OB?
If you think that this last solution will definitely fly right, there may be one other concern: Gary’s Altec cabinets are 20” high-maybe an inch or two higher, if you happen to think I will need this on a carpeted room Auralex BabyGRAMMA v2 Isolation Riser | Sweetwater.com ).
My living room’s about 19 ft x 14, not that small, but how concerned should I be about being on vertical axis with the 10” TT in the OB, sitting atop the Altecs and the RAAL ribbons mounted in the OB right above the TTst?
Finally, it’s a shame the Nelson Pass’s First Watt amps would likely be a bad match for a horn system. I would have very seriously considered using just about any horn system you would suggest for this system with the 416s-or for how my bedroom system will take shape. You say that horns“….retain their trademark clarity and vividness at very quiet playback levels…..If casual background listening is the primary goal, full range backhorn-loaded speakers are the first choice. They sound cohesive and effortless when played at quiet and medium levels, and there are never any issues with the dynamic tracking of different drivers at different levels.” And much of my “bedroom music” will be of a type for fairly low, if not quite low level listening. But I already have a pair of Nelson’s amps for each system and I’d prefer to go with drivers that will work with them. Given that situation, I hope that one of these driver configurations will well together, and for the type of music I want to play in my living room.
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Oltos,
I just don't follow at all your logic of using the Tone Tubby speakers in a playback system. You are going to all the trouble to duplicate the Altec design from Gary Dahl and then your going to ruin the entire thing with a guitar speaker? If space is not a consideration for your large room why not just do the right thing and get some compression drivers and horns or at least consider a three way system with a mid-range cone driver and dome tweeter if that is what you would want to do. Then you could use the dome tweeter from Seas if you insist and put something that will cover the mid-range that the dome tweeter could never do. A smaller 6" or 4" driver to fill in the missing section that is just asking to much of the Altec or the Seas to cover.
I just don't follow at all your logic of using the Tone Tubby speakers in a playback system. You are going to all the trouble to duplicate the Altec design from Gary Dahl and then your going to ruin the entire thing with a guitar speaker? If space is not a consideration for your large room why not just do the right thing and get some compression drivers and horns or at least consider a three way system with a mid-range cone driver and dome tweeter if that is what you would want to do. Then you could use the dome tweeter from Seas if you insist and put something that will cover the mid-range that the dome tweeter could never do. A smaller 6" or 4" driver to fill in the missing section that is just asking to much of the Altec or the Seas to cover.
I have no connection to Madisound but they sell Markaudio...
https://www.madisoundspeakerstore.c...ode=search&search_in=all&search_str=markaudio
https://www.madisoundspeakerstore.c...ode=search&search_in=all&search_str=markaudio
oltos,
I don't have a vinyl system up and running yet. I use a Modwright Sony cd / sacd player for now and is more than adequate plus over 2000 cd's, sacd's. I have heard several "high rez" files from different sources and some did not impress me. I will have a server system in the not too distant future. If you want to hook up your computer / dac to my Cary SLP-05 preamp, have at it.
I don't have a vinyl system up and running yet. I use a Modwright Sony cd / sacd player for now and is more than adequate plus over 2000 cd's, sacd's. I have heard several "high rez" files from different sources and some did not impress me. I will have a server system in the not too distant future. If you want to hook up your computer / dac to my Cary SLP-05 preamp, have at it.
I think microphone choice and placement, post production mixing and mastering skills, and quality of music and performance completely trumps any high res / low res considerations. I'd rather hear an mp3 with these factors well addressed than many a hi-rez file (with low grade production values) I've heard—even for 'serious listening'.
The whole ribbon tweeter / big woofer thing seems like a non-starter to me. You're going to use a big woofer that will have narrowing directivity at its high end and then cross it to a ribbon which will have very wide directivity. That's a recipe for a bad speaker. Big woofer plus similar sized midrange horn is a recipe for a good speaker - the directivity of the two devices will be closer to matching at the crossover, and if you do the crossover right you won't have an abrupt shift in the power response of the system. This will help reduce tonal coloration.
I concur with John Sheerin. In addition, there's issues with grossly dissimilar efficiency (10 dB) and headroom (more than 10 dB) between stats and a 416-class 15" driver.
I did enjoy listening to the B&W Model 70 many years ago (at Radio People in Hong Kong in 1971), and that did use a curved ES panel sitting above a bass enclosure with a closed-box 12" or 15" driver. It was a nice-sounding speaker, legendary in some circles, but the join between the LF and HF was pretty obvious. It wasn't a matter of crossover, which B&W has always been pretty good at, but the character of the drivers being so different. The B&W woofer was a heavy-cone AR-1W type driver, and mid transparency was not all that good. The 200 Hz range sounded slow, while 2 kHz shimmered in the usual electrostatic way.
Integrating electrostats with direct-radiator bass has always been difficult ... Martin-Logan has been doing this for decades, and subjective integration is still kind of marginal, just as it was back in the days of the AR-1W and the JansZen Z-130. It's just not an easy thing to do, and plenty of people have tried their luck at it over the last sixty years.
Horn + 15" driver? You betcha. A studio favorite going back to the Thirties. Lots of famous records were mastered on systems just like this ... the Lansing Iconic, Altec 604 Duplex, Altec A7 and A5, Tannoy 15" in studio cabs, the UREI Big Reds, the list goes on and on. This is pretty much the classic studio-monitor formula.
And horns have gotten better ... much, much better than the Golden Age of the Fifties. This is where modern computer modeling has really paid off big-time. There's Dr. Earl Geddes' Oblate Spheroid, Dr. Bjorn Kolbrek's thoroughly analyzed AH425's, various modern horns optimized for low-diffraction, etc. etc.
The only real choice from a horn perspective is the choice of small-format 1" exit compression drivers, which will need a crossover in the 1~1.5 kHz range, or a large-format 1.4" to 2" exit driver. Large-format drivers and horns can use a crossover from 500 Hz to 800 Hz, but are not really at their best above 10 kHz. (It's still a good rule-of-thumb to not use horns over more than 3 octaves, but there are exceptions.)
I chose a large-format compression driver because I really like how they sound in the 800 Hz to 2 kHz region ... but that also meant accepting a matching supertweeter. I like Beryllium and traditional aluminum alloy diaphragms ... and don't like titanium (which is what is used in modern movie theaters).
Plenty of people really like small-format compression drivers; you just have to use a somewhat higher crossover. No supertweeter is needed, and modern plastic diaphragms are much sweeter-sounding than the titanium diaphragms that are widely used in portable PA systems.
The only real alternative to a horn is an modern AMT driver like the TPL-150; these are efficient, with studio-monitor headroom (to match the bass driver), and have pretty flat response. (Plastic diaphragm with aluminized conductive coating.)
Ribbons and true electrostats are not a good match for a studio-monitor 15" driver; they work a lot better with audiophile-style 6" to 8" midbass drivers, and associated 87 dB/meter/watt efficiencies. A system like this has 10 to 15 dB less headroom than a traditional large-format studio monitor.
Entirely aside from issues of coloration, high-efficiency speakers (and I'm not talking Lowther or full-range Fostex here) have a very different dynamic presentation than high-quality audiophile speakers. It's hard to describe unless you've heard it for yourself.
I have friends who really love the Tone Tubby + Lowther/OB setup, but it's not my thing. I actually feel kind of guilty about my TT writeup; what I really wanted were more hempcone drivers, but as usual, politics have gotten in the way. Maybe the cone manufacturer should move to Colorado; hemp and hemp products are state-licensed and legal here, and we have lots of high-tech manufacturers in the Denver/Boulder/Fort Collins corridor.
I did enjoy listening to the B&W Model 70 many years ago (at Radio People in Hong Kong in 1971), and that did use a curved ES panel sitting above a bass enclosure with a closed-box 12" or 15" driver. It was a nice-sounding speaker, legendary in some circles, but the join between the LF and HF was pretty obvious. It wasn't a matter of crossover, which B&W has always been pretty good at, but the character of the drivers being so different. The B&W woofer was a heavy-cone AR-1W type driver, and mid transparency was not all that good. The 200 Hz range sounded slow, while 2 kHz shimmered in the usual electrostatic way.
Integrating electrostats with direct-radiator bass has always been difficult ... Martin-Logan has been doing this for decades, and subjective integration is still kind of marginal, just as it was back in the days of the AR-1W and the JansZen Z-130. It's just not an easy thing to do, and plenty of people have tried their luck at it over the last sixty years.
Horn + 15" driver? You betcha. A studio favorite going back to the Thirties. Lots of famous records were mastered on systems just like this ... the Lansing Iconic, Altec 604 Duplex, Altec A7 and A5, Tannoy 15" in studio cabs, the UREI Big Reds, the list goes on and on. This is pretty much the classic studio-monitor formula.
And horns have gotten better ... much, much better than the Golden Age of the Fifties. This is where modern computer modeling has really paid off big-time. There's Dr. Earl Geddes' Oblate Spheroid, Dr. Bjorn Kolbrek's thoroughly analyzed AH425's, various modern horns optimized for low-diffraction, etc. etc.
The only real choice from a horn perspective is the choice of small-format 1" exit compression drivers, which will need a crossover in the 1~1.5 kHz range, or a large-format 1.4" to 2" exit driver. Large-format drivers and horns can use a crossover from 500 Hz to 800 Hz, but are not really at their best above 10 kHz. (It's still a good rule-of-thumb to not use horns over more than 3 octaves, but there are exceptions.)
I chose a large-format compression driver because I really like how they sound in the 800 Hz to 2 kHz region ... but that also meant accepting a matching supertweeter. I like Beryllium and traditional aluminum alloy diaphragms ... and don't like titanium (which is what is used in modern movie theaters).
Plenty of people really like small-format compression drivers; you just have to use a somewhat higher crossover. No supertweeter is needed, and modern plastic diaphragms are much sweeter-sounding than the titanium diaphragms that are widely used in portable PA systems.
The only real alternative to a horn is an modern AMT driver like the TPL-150; these are efficient, with studio-monitor headroom (to match the bass driver), and have pretty flat response. (Plastic diaphragm with aluminized conductive coating.)
Ribbons and true electrostats are not a good match for a studio-monitor 15" driver; they work a lot better with audiophile-style 6" to 8" midbass drivers, and associated 87 dB/meter/watt efficiencies. A system like this has 10 to 15 dB less headroom than a traditional large-format studio monitor.
Entirely aside from issues of coloration, high-efficiency speakers (and I'm not talking Lowther or full-range Fostex here) have a very different dynamic presentation than high-quality audiophile speakers. It's hard to describe unless you've heard it for yourself.
I have friends who really love the Tone Tubby + Lowther/OB setup, but it's not my thing. I actually feel kind of guilty about my TT writeup; what I really wanted were more hempcone drivers, but as usual, politics have gotten in the way. Maybe the cone manufacturer should move to Colorado; hemp and hemp products are state-licensed and legal here, and we have lots of high-tech manufacturers in the Denver/Boulder/Fort Collins corridor.
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Yes. I know of no speaker technology that is equally good at all types of music. Plenty of people might disagree with me, but that's how I feel about it. Price, fame of the manufacturer, and good reviews have nothing to do with it; the technology and materials science have inherent limitations at the current state of the art, and different technical solutions favor different types of music and different types of musical tastes.
OK, I'm going to step on some toes here. The Sound Labs is a first-class loudspeaker that is 100% aimed at the mainstream audiophile market. It is also the polar opposite of what the triode/high-efficiency enthusiasts are all about.
I don't really have the language to describe the difference, but Sound Labs A1's powered by 200-watt Krells are one end of the spectrum, and Altecs powered by 300B's, push-pull KT77's, or a Pass single-MOSFET amplifier are on the other end of the spectrum.
Maybe two inherently different-sounding technologies (with different power requirements) can be brought together, but I'm not the one to do it.
No, no, and no. Sorry to be so negative, but these don't work together. Ribbons are at their best in the VHF range. Power-handling isn't one of their strengths, although the RAALs probably have the best power-handling of any ribbon. Think 7 kHz and above.
I for one disagree. Mainly, because it's the complete system, as a unified entity, that makes or breaks the subjective quality of the playback.
What I aim for is to ensure that samples of the most intense, high energy, heavily layered recordings, irrespective of genre, don't show up audible deficiencies in the system, in the volume range of interest. If this is achieved then all recordings will come across well, IME. I don't see problems in the technology, rather a lack of attention to details that nearly always trips up all systems, irrespective of money and amount of engineering focus on the conventional, small range of issues.
Of course. There should be no doubt on that. But the electronics have contribution too.
A simple example is about "speed". Big diameter woofers have heavy cones. They are not "fast" enough for HF dynamics. Even most dome tweeters have limitation with "speed" at their low usable bandwidth.
A music type that requires "speed" is a symphony. Listen for a crescendo followed by an "explosion" (what do you call this musical execution?). MANY speakers will show it's limitation when producing this music. At some point you need a (speaker) comparison to know which one is right and which one is wrong, but regarding "speed", often it is slow enough that it will ruin the music such that you will know even without A/B comparison.
I support Lynn in his context of loudspeakers. You really need to have had a wider technical background and been into audio reproduction for decades and tried the many diverse options first hand. If you have this and common sense you do realise something about the selection process to produce a good speaker, a good system.
My view I repeat here, is that the right cheap driver choice and system match can for normal listening levels be at the very top. DIYers forget the Rolex syndrome. Forget turning it up to over 120dB +. That is another arena. 90dB with peaks of up to 120dB is affordable
The TWO34 P47N version Troels specifies is a great tweeter with heavy ferrite magnet with cloth dome, no faraday rings, yet Troels suggests the T35 is perhaps marginally better as a Neodymium, state of the art silk dome tweeter. A no brainer. Audio apparatus must not become an investment but rather a replaceable device that wears out.
Taking an identical driver and changing from a ceramic magnet to an Alnico or Neodymium magnet will lower the distortion by only that fact, less eddy currents than the cheap ceramic. At the same time many great sounding devices still use ceramic magnets.
I have a bit of trouble getting my head around one speaker system being better than another for a certain type of music. The only way I can think of that is that in certain music it could be simpler and have a different balance to the spectral content. But the way I think about it is that a speaker where it can handle the fast transients and can handle the dynamic range of the most complex music should in theory be able to handle any lessor demand, a great speaker should be capable of doing it all, a lessor system may be limited to simpler music or less dynamic range. Some may prefer a very directive speaker system and others may want a very diffuse sound field like an omnidirectional speaker, think MBL or Bose 901, that is more a personal choice than wanting an accurate reproduction of the source material.
I have a bit of trouble getting my head around one speaker system being better than another for a certain type of music. The only way I can think of that is that in certain music it could be simpler and have a different balance to the spectral content. But the way I think about it is that a speaker where it can handle the fast transients and can handle the dynamic range of the most complex music should in theory be able to handle any lessor demand, a great speaker should be capable of doing it all, a lessor system may be limited to simpler music or less dynamic range. Some may prefer a very directive speaker system and others may want a very diffuse sound field like an omnidirectional speaker, think MBL or Bose 901, that is more a personal choice than wanting an accurate reproduction of the source material.
I believe that if it were possible to make a perfect loudspeaker, it would work perfectly with all types of music. Every real-world speaker I have heard, however, is the result of the compromises chosen by its designer. The sonic consequences of these compromises don't impact all types of music (or listeners) equally.
For example, I have heard speakers that sounded wonderful while playing music that would normally be performed with electronic amplification in a live setting, but didn't sound very good at all playing classical music. If I were trying to build a system for listening to the former, I would likely choose different compromises than I would in a system intended for the latter.
I'm not in a position to know precisely why the alnico GPA 416 in a sealed box sounds so musically "right" to me, but after so many years of seeking realistic orchestral reproduction, its virtues were immediately obvious upon first listening. Someone with different listening habits may or may not come to the same conclusion.
I am looking forward to hearing reactions from the attendees at the DIY Showcase event (a joint activity by Sound DIY and Pacific NW Audio Society) at the end of the summer. It will be the first time my speakers have been heard outside my home, in a room more familiar to the other listeners.
Gary Dahl
For example, I have heard speakers that sounded wonderful while playing music that would normally be performed with electronic amplification in a live setting, but didn't sound very good at all playing classical music. If I were trying to build a system for listening to the former, I would likely choose different compromises than I would in a system intended for the latter.
I'm not in a position to know precisely why the alnico GPA 416 in a sealed box sounds so musically "right" to me, but after so many years of seeking realistic orchestral reproduction, its virtues were immediately obvious upon first listening. Someone with different listening habits may or may not come to the same conclusion.
I am looking forward to hearing reactions from the attendees at the DIY Showcase event (a joint activity by Sound DIY and Pacific NW Audio Society) at the end of the summer. It will be the first time my speakers have been heard outside my home, in a room more familiar to the other listeners.
Gary Dahl
Seriously, it doesn't bother me. I publish occasionally in this thread because a few readers might be interested in my thoughts. If the S/N ratio goes down, I leave the forum for a few days or weeks, and return to private correspondence with my collaborators.
Part of the horn community are sympathetic to the low-power DHT and PP-pentode enthusiasts, and another part thinks transistor amps (and DSP) are just fine. These two groups sometimes talk past one another, since the subjective and technical goals are different.
Similarly, the DHT-triode folks are not going in the same direction as high-watt mainstream high-end audio. They parted ways in the late Eighties, and there hasn't been much convergence since then.
I've never met or phoned Oltos, so I have no idea how much Oltos has been exposed to the direct-heated, high-efficiency Sound Practices culture of the Nineties. I'm not 100% with the SP crowd, but I'm sympathetic and know where they're coming from. The best way to explain it is that I'm traveling in a parallel track that is close but not quite the same.
I never intended to imply the Pass single-MOSFET amplifiers are "bad"; I just don't understand them, or the appeal of the sound. I like vacuum tubes, for all their hassles, much better, and I like speakers that work well with them. The Ariels were designed for moderate-power vacuum-tube amps, and the new speaker is designed for the same kind of amplifier. There are working versions, being used with vacuum-tube amplifiers, in Washington State, Canada, the Greek Isles, Norway, and Australia. My hifi neighbor, Thom Mackris, and I will be building our set in the near future.
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Hi Lynn,
Going double seems interesting, I think you might gain some control on the horizontal dispersion that way. I am sure you've seen Rod Stewards RobSpeaker with 2x416+288+ST, which is pretty similar to what you are considering.
I have been wondering 1) how high would you cross the double 416s (using two will lower the max crossover point vs using a single)? and 2), (what interests me more) how have you thought to use the 515 + 416 combination? What do you think are the advantages of this over the double 416?
Have you considered a resistively ported/aperiodic enclosure ported to a larger sealed one behind/below? This would help with standing waves associated with larger cabinets and would flatten the imp curve @ resonance. There is a WD speaker design like this. If the 416 works in a closed box it should work like this.
(in one of the last classic articles on the onken there was a thick absorber placed behind the woofer, much separated from the back wall. I don't have the article anymore, but I think (?) it was almost a separation of the enclosure in two (I must look for it))
A single 416 doing well without a sub in a 4 cft sealed enclosure would be a pretty nice. How low would this go? I have been thinking of doing an onken with a 416 for some time now the size difference is considerable!
Finally one question: are 10 or 12" divers considered too large for a good (small) low mid front horn?
Going double seems interesting, I think you might gain some control on the horizontal dispersion that way. I am sure you've seen Rod Stewards RobSpeaker with 2x416+288+ST, which is pretty similar to what you are considering.
I have been wondering 1) how high would you cross the double 416s (using two will lower the max crossover point vs using a single)? and 2), (what interests me more) how have you thought to use the 515 + 416 combination? What do you think are the advantages of this over the double 416?
Have you considered a resistively ported/aperiodic enclosure ported to a larger sealed one behind/below? This would help with standing waves associated with larger cabinets and would flatten the imp curve @ resonance. There is a WD speaker design like this. If the 416 works in a closed box it should work like this.
(in one of the last classic articles on the onken there was a thick absorber placed behind the woofer, much separated from the back wall. I don't have the article anymore, but I think (?) it was almost a separation of the enclosure in two (I must look for it))
A single 416 doing well without a sub in a 4 cft sealed enclosure would be a pretty nice. How low would this go? I have been thinking of doing an onken with a 416 for some time now the size difference is considerable!
Finally one question: are 10 or 12" divers considered too large for a good (small) low mid front horn?
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Using the measured values of my own GPA 416's in the mh-audio modeling software, a 4-foot sealed cabinet would produce a system Q of .798 and be -3 dB at 53.8 Hz. This could be accomplished with a box having inside dimensions of about 30.7" H x 19" W x 11.75" D.
I would expect the resulting cabinets to sound quite satisfying without subwoofers, depending of course upon the expectations of the listener. But keep in mind that the 416, with its underhung voice coil, has relatively limited excursion. One would need to account for this when using it at lower frequencies without bass reflex loading. In my case, limiting the LF extension is beneficial.
Gary Dahl
I would expect the resulting cabinets to sound quite satisfying without subwoofers, depending of course upon the expectations of the listener. But keep in mind that the 416, with its underhung voice coil, has relatively limited excursion. One would need to account for this when using it at lower frequencies without bass reflex loading. In my case, limiting the LF extension is beneficial.
Gary Dahl
Low A on a Piano is 27.5Hz. Deep bass is required, but there is a significant difference between Boom-Boom heavy cone subwoofer bass, and room-equalized high-efficiency big-cone-woofer bass.
==== Sd vs. cone diameter===
18" 1220 cm2
15" 855 cm2
12" 530 cm2
10" 345 cm2
8" 225 cm2
The large cone area of an 18" woofer provides high efficiency bass with modest distortion generating displacement. Side-to-Side physically connected woofer pairs use counter-forces to dramatically reduce vibrations. Two 18" woofers can provide high quality room-equalized bass from a sealed box alignment with modest watts. Two 18" woofers like (Faital 18FH500, Peavey LoRider18, Beyma 18LX60 rev1) which have modest Mms (140-180g) and Qts~ 0.37 connected in parallel in a sealed 9cuft volume can provide Qtc=0.7 alignment with F3=60Hz before equaliztion extends the bass to the 20-30Hz range using 10watts for over 100db room SPL. Smaller sealed volumes require greater power for room-equalized low frequency bass.
Sealed box volume vs. amplifier boost power using a Linkwitz Transform of 20Hz for a pair of Faital 18FH500
Two Faital 18FH500 woofers producing 100db SPL with -3db at 20Hz Linkwitz Transform
Box Volume = 9cuft____Qtc=0.70___Power for 98db SPL @30Hz = 10.4watts
Box Volume = 8cuft____Qtc=0.73___Power for 98db SPL @30Hz = 12.5watts
Box Volume = 7cuft____Qtc=0.76___Power for 98db SPL @30Hz = 15.5watts
Box Volume = 6cuft____Qtc=0.80___Power for 98db SPL @30Hz = 20.2watts
==== Sd vs. cone diameter===
18" 1220 cm2
15" 855 cm2
12" 530 cm2
10" 345 cm2
8" 225 cm2
The large cone area of an 18" woofer provides high efficiency bass with modest distortion generating displacement. Side-to-Side physically connected woofer pairs use counter-forces to dramatically reduce vibrations. Two 18" woofers can provide high quality room-equalized bass from a sealed box alignment with modest watts. Two 18" woofers like (Faital 18FH500, Peavey LoRider18, Beyma 18LX60 rev1) which have modest Mms (140-180g) and Qts~ 0.37 connected in parallel in a sealed 9cuft volume can provide Qtc=0.7 alignment with F3=60Hz before equaliztion extends the bass to the 20-30Hz range using 10watts for over 100db room SPL. Smaller sealed volumes require greater power for room-equalized low frequency bass.
Sealed box volume vs. amplifier boost power using a Linkwitz Transform of 20Hz for a pair of Faital 18FH500
Two Faital 18FH500 woofers producing 100db SPL with -3db at 20Hz Linkwitz Transform
Box Volume = 9cuft____Qtc=0.70___Power for 98db SPL @30Hz = 10.4watts
Box Volume = 8cuft____Qtc=0.73___Power for 98db SPL @30Hz = 12.5watts
Box Volume = 7cuft____Qtc=0.76___Power for 98db SPL @30Hz = 15.5watts
Box Volume = 6cuft____Qtc=0.80___Power for 98db SPL @30Hz = 20.2watts
Attachments
Lynn, are you using any diffusers or other treatments in your setup?
I ask because I think those are what made the most difference in getting ambience and spatial quality improvement in my system. A set of 1D diffusers about 5ft behind and to the sides (and also where they are directly in line of fire from the crossfired horns). More so than SETs that I've had connected, even.