System that sounds so real it is easy to mistaken it is not live

"The vast majority of albums are recordings?"  "Who knew? "

@wolf_garcia 

It was sarcasim ...you missed it  ... before your sarcastic reply. 😉 too funny...

No sarcasm backtracking...deduct 9 points.

No. Not even close. Although, playing a Taylor 410 myself, Magnepans seem to get closest to an acoustic guitar.

Absolutely!

Closest I have come is when I was playing solo piano on vinyl, and my wife who is a pianist was a couple of rooms over called out to me and asked who was playing (she knew that I don't play and thought that I had a visitor sitting at her piano.

“In another room “ stories are absolutely irrelevant. When the source is in another room with respect to the room inhabited by the listener, the ear and brain are deprived of several cues used to distinguish live from reproduced music. Phase and bandwidth included. When it’s an unaccompanied vocalist or single instrument, it becomes plausible that you’re hearing a live musician, until you check it out by entering the space containing the source.

The fun thing here is knowing that microphones, electronics and headphones have been so real sounding they can fool a jaundiced audiophile and have been able to do so for decades.

I can recount several experiences where this was underlined in spades. I won't do all of them, here's one (ask if you want more): I was doing an on-location recording of a choir concert about 30 years ago, using an Ampex 351-2 tape machine, a set of Phillips small diaphragm tube condenser mics and a set of $20.00 Radio Shack headphones. After the intermission the choir was gathering at the other back stage door from the one at which I was stationed. Apparently they were going to do a number where they walked in while singing. So I rolled the tape. All of a sudden someone started singing behind me; I figured they were a soloist going to enter the door where I was. I looked around but no-one was there; I had missed the soloist entering the stage earlier (luckily got the tape rolling in time...)!

I could never get the machine to do that off of the tape playback, but off of the mic feed it was easy. Sometime if you get a chance, get your hands on a Zoom recorder or the like and headphones and see how easily you can talk while its in record mode. If you tend to shut up when someone else is talking you may find it hard to talk in this situation until you get used to it, especially if your voice is delayed. That's how real sounding mics and headphones actually are.

When we use speakers playing in a room and using a recorded media its another kettle of fish and much harder to get that spooky real thing I referred to in my first post on this thread.

Dear @mijostyn: Sorry but  everything the same your statements are wrong, it does not matters the quality level of your room/system.

 

I have no doubt that your system performs really good but even that fact it's far away, more that what you believe through your first hand experiences, from live MUSIC and if you still think that way then your ears are foolishing you.

 

Now, you post very often that listen at 95db SPL seat position that means that peaks could goes as higer as 105db SPL. I don't know if your seat position is at 1m. or 3m-5m,, maybe between 3m-4m.. Your Soundlabs has a sensitivity of 89db SPL at i meter and I'm wondering which distortion levels you measured at your seat position at that 95db-105db SPL that seems could be higher than the live MUSIC levels.

Btw, you posted that crossover speakers degrades the signal but the transformers in your speakers does it too . Nothing is perfect.

Anyway there are a few issues against what you posted.

 

Regards and enjoy the MUSIC NOT DISTORTIONS,

R.

We wholeheartedly agree that there is nothing that compares to a live performance, whether it’s on a street corner or in a concert hall. All of the attributes ultra high-end systems seek to replicate are experienced in these live venues. Many advances have been made in modern high-end audio equipment to optimize impulse response.

 

Traditional systems, especially the speakers, distort the phase on a frequency by frequency basis. This muddies the impulse response and takes away the depth, layering and imaging of sound that comes from being in the same space with the musicians.

We work extensively with Dirac Live in audio systems, and it has brought us closer to the goal of recreating the feeling and texture of a live performance.

 

 

@atmasphere , come on Ralph you just squish them in there. Hold that thought:-)

@lewm , the 6 ohm MC Diamond has more gain in voltage mode, about 3 dB. It definitely sounds better in transimpedance mode. Bass drums have more punch and the bass has more definition. I spent 30 minutes going back and forth on a number of different records. You can't hear the background noise until the tonearm lifts but then there is a hiss you can hear clear across the room and you know how tall ESLs are when it comes to projecting noise. This is at 95 dB or minus 6 dB FS. The Seta L 20 is 12 dB quieter, an awfully expensive solution. 

Is is not that a system should sound exactly like a specific live performance. It is that a system should be able to convince you that you are sitting in front of a live one and supply a similar amount of sonic satisfaction. The experience will never be the same without the visual aspects. A BluRay player and a large screen can take care of that. May not be quite the same but then you do not have to fight the crowds or the traffic. 

@rauliruegas , thanx a bunch Raul. I sit 4 meters away. You have to remember That my system is line source. It's volume does not fade with distance like a point source system will. Yes, each main speaker has two transformers. They are nothing near as complicated as the crossovers in most modern high performance speakers. I also take the bass below 100 Hz out of them with 48 dB/oct digital filters which increases their headroom rather dramatically. 105 dB peaks is not a problem at all. Each one has a 350 watt amp on it and each subwoofer has 1800 watts on it, all 4 of them. 

Your Soundlabs has a sensitivity of 89db SPL at i meter

@rauliruegas Being that the Sound Lab is a large curved panel, you have to add 6dB to the rating to find out the effective sensitivity when you are back about 10 feet. The reason is that at 1 meter most of the output of the speaker is not picked up by the microphone. Roger's sensitivity numbers on his website doesn't tell the whole story, since sensitivity is a voltage measurement and so impedance is pretty important. The Sound Lab is 30 Ohms in the bass (the sensitivity is stated for 8 Ohms), meaning its efficiency is actually higher by a good 3-6dB in the region where most of the power exists.

The speaker isn't hard to drive for any other reason than impedance. If you have amps that can drive the impedance the numbers @mijostyn provided are entirely realistic in many rooms.

Much of the energy used to drive the Sound Lab is soaked up by the passive crossover, because SL (for other compelling reasons) chose to use a resistance in the RC network that comprises the high pass filter that is much lower than the natural impedance of the panel itself, sans RC network. Thus the amplifier is expending more energy to drive the resistor than to drive the panel. With RC network removed, the big SLs are remarkably efficient and present an impedance in the 20 to 25 ohm range (never below 20 ohms) from about 100Hz to 5kHz. Impedance goes up below 100Hz and down between 5kHz and 20kHz. This gets rid of the midrange impedance issue that Ralph alludes to. And of course it’s favorable for an OTL tube amp. I daresay that a 50W amplifier is sufficient; my Atma-sphere amps with about 100W are coasting. Of course, you also have to replace the treble audio trans with a suitable full range audio trans. They’re not easy to find.

Many years ago as an audio dealer peddling "descent stuff" , I attended a concert featuring the Polish national champion string quartet -- to "recalibrate" my ears.  It didn't take long to come to the realization that our equipment was embarrassing insufficient at replicating the experience of a live performance.  The lack of lower midrange detail struck me as the most prominent deficiency.

As a result we upped the ante on just about everything in the musical chain and lived happily every after.  Well, for 2 more decades, anyway.  

Sarcasim is obvious ....points restored...

Claiming to read minds when doesnt read post,  automatic disqualification for Sheldon Garcia...

Haven't been to a lot of live concerts, but if my system would sound like the ones I have attended (including most recent on), I would trash it immidiately and get my 80s boom box out as an upgrade. 

@dekay Sorry.  Slip of the typing finger.  1971, Bristol VA/TENN King College (now "University") concert.  We played a set, they played a set.

Will promise to proofread my posts from now on!!

Cheers!

@atmasphere , not to mention that mine are 8 feet tall which means the volume does not dissipate nearly as quickly as point source systems. Horns can make up for this with extreme efficiency and controlled dispersion. Other dynamic speakers not so much.  

@lewm , tell me about it. For some strange reason Sowter stopped making ESL transformers and the ones I have found are peanut 50 or 75 to one jobs that will not handle the power I could throw at them. That resistance is primarily in the treble region, that Brilliance control which I roasted fine tuning it. I substituted the appropriate sized power resistor and it will heat the chassis almost to the point where you can not keep a hand on it. More wasted power. You still have to keep a resistor on the primary for most amps, just an ohm or two to keep them from shutting down. Since I take the bass and can fine tune the frequency response digitally I should easily be able to get away with one transformer and maybe a resistor if I could fine one with suitable power handling. I do not think the HF toroid will handle it. Roger is of the mind that you do not want to modify his speakers for any number of reasons.

@atmasphere , Ralph, do you know any makers of ESL transformers that could supply a 100:1 step up able to handle 200 watts continuous with a frequency response of 100 Hz to 20 kHz?

Many years ago, I recall reading some literature about Klipsh.

Their contention was that one of the most difficult sounds to reproduce was 

scissors cutting a piece of paper.

richopp:

I also have difficulty placing things during that time period for some reason.

Duane died when I was a sophomore in HS, so that narrowed it down to 71 (as I recall that it was around Halloween).

I saw them in Des Moines, Winter of the following year, and ended up driving to Illinois to  their next concert the following day.

No Dwayne, but Betts was incredible (playing from a pool of sweat both times). 

 

DeKay

Dear @mijostyn : My dynamic type speakers can be operated in line source or point source fashion, we have to remember that ADS designed it as true proffesional/studio monitors and not for home systems.

 

My seat position is at 2m.-3.m. and sensityvity ADS spec is 95db. Normally I listen it in the 80's db SPL and only go to 95db SPL at seat position or even a little higher when I’m testing or comparings audio items. I like to take care of my way limited ears.

 

Btw, thank’s @atmasphere .

 

R.

@rauliruegas , I think we may have different definitions of point and line source.

A point source is a driver that is smaller in all dimensions  than the shortest wavelength it is to reproduce. I line source is a driver that is larger in at least one dimension than the largest wavelength it is to reproduce. There are drivers that can be line sources at higher frequencies and point sources at lower frequencies. There are only two drivers that are line sources from zero hertz to over 20kHz. The first is an infinitely tall one and the second is a tall or long one that both ends terminate at fixed barriers like a floor, ceiling or wall. It is impossible for a driver to be both full frequency line source and full frequency point source. It is actually very bad for a speaker the swap radiation characteristics mid audio band as the power projection is very different and will cause frequency response  aberrations that vary with distance. 

Both my ESL and subwoofer systems end at fixed barriers. My system is line source from zero to as high as the ESLs will go which is probably not higher than 18 kHz. Roger West won't publish that spec. I am toying around with inserting a ribbon tweeter to go from 12 kHz up. This would relieve the main amp from having to deal with the crazy impedance curve of ESLs up there and give me a little more flexibility. I will have to biamp it and add a second digital crossover. 

Fact is, it is rare that reproduced and live sound is nearly identical. Once a system accomplishes this the experience is spellbinding (big understatement).  I read many reactions to thisr post, who "believed" this not possible. But this is a clear admission they have never experienced this.  Nay-saying the possibility is no excuse for slacking from the works it takes to achieve it.  In this case, there is no rule to be broken. 

I suspect that some form of Aromatherapy would be required in order to truly recreate a live musical performance @ home.

Did anyone see John Waters "Hairspray" in the 80's?

 

DeKay

Yes this can be done, I have done it.  It took many years to find the secret. I’m good friends with a well known rock band and as so I get requested to see their performance often. At one of these gigs the band sounded incredible, twinkling highs and thunderous bass, above average. So I made my way to the sound engineer and he introduced me to the DBX drive rack. A standard looking peace of equipment that can correct music output for any environment. So l took a chance on it, it is pro equipment so there was a big learning curve and it’s built with XLR connections only. After a few weeks of learning and tweaking, great results the DBX can filter and adjust anything you throw at it (room acoustics, sound nodes etc.) great for people that don’t want to cover there room with acoustic treatments and have to keep the wife happy. One of my inherent problems was speaker placement, one is next to a side wall and one not, so l always had a speaker with wall induced sound reinforcement. With the DBX I can correct each speaker separately so that problem solved. It works with a microphone and can store as many programs as you want. I set mine as the perfect concert hall, and love it. It also doesn’t hurt that I’m running four 15” woofers and a total of 3800 watts. But that’s what it took to get live venue sound like the pros do it. One last thing only buy gold plated connectors or you will develop a hum when the tin connections gets tarnished. Best of luck in your pursuit of great sound and don’t forget it’s about the music enjoyment not the sound.

P.S. I forgot to mention that I do not run cross overs. The DBX has its own digital fully adjustable. You just need one amp channel for each speaker, so I run a 200 watt AB amp to the tweeters, 300 watt AB to the mids and 3000 watt class D to the subs in a open baffle configuration. DIY inspired by Jamo 909s.

Mijo, This is perhaps not the place to discuss it, for fear of boring a few others, but I have been there, done that, when it comes to audio transformers for the SL speakers. First, a single transformer with a 1:100 step-up ratio does not cut the mustard for good bass response from the panel. Of course, since you are subwoofer supplementing, perhaps you could get away with some compromise, but so far as we have been able to find out, the bass transformer on our speakers is 1:250, or something close to that range. (SL will not divulge the information.) And you do not want a full-range trans with such a high step-up ratio, because that will produce very low input impedance as frequency goes up. (Remember that an ESL is naught but a giant capacitor.) For the full-range transformer in my speakers, which I couple with the OEM SL bass transformer at low frequencies, I use a 1:90 ratio in a very hefty step=up that was made in Australia. Unfortunately, that model is discontinued but the same company may make a suitable substitute. Anyway, I tried driving my SLs with the Australian transformer full range without any bass transformer, and the bass to low mid-range was very anemic, totally unacceptable in fact. So, there’s a reason that SL uses two transformers to achieve a robust full range response. I use a single huge air core inductor to roll off the OEM SL bass transformer somewhere in the low midrange, in parallel with the 1:90 Australian transformer running full range with no RC network at all. In theory, you’d think that might present problems. In fact, the first time I heard it in my home, it brought a tear of happiness to my eye. If I were to do this today, and if the Australian company don’t have a suitable substitute for the discontinued units I use, I would consider the full-range 1:75 toroidal transformer made by Plitron. A small benefit of that unit would be slightly higher impedance at high frequencies, compared to what I’ve got. But you are way too concerned about the Z at high frequencies, in my opinion. You once mentioned that you boost response by 6db per octave above 12kHz. That probably contributes to heating up your crossover. But more than a decade ago, some SL users found that the higher the power rating of the R in the treble RC network, the better was the sound. Guys were using humongous resistors that did not even fit into the backplate. (I was one of them.) But real happiness is no RC network at all.

One last thing only buy gold plated connectors or you will develop a hum when the tin connections gets tarnished.

@5windowcoupe Tin and gold share a property which is they boh are resistant to corrosion! This is why tin is often used in connectors and the like. If your tin connections are getting corroded, you've got some kind of chemical involved that is responsible or the connectors are so worn that the copper beneath has been exposed. Tin is often preferable to gold since it is so much harder and therefore harder to wear off when the connector is plugged in and out.

You have to remember That my system is line source. It's volume does not fade with distance like a point source system will.

There's probably a Nobel waiting for someone to show the inverse square law doesn't apply to sound from any source.

Yes my giant horns have gotten more than a few is that a real band playing in your home comments. A few speakers have horns that were actually used in concerts by some of my favorite acts a few shows I attended had the horns in use. When I play back a live recording of some of the bands I get a spooky real sound quality that's damn near real sounding. I also have real theater horns these can playback movies so that it sounds like a real theater but with higher-quality playback.

I never thought it’s possible to listen to a system that make you feel you are on the concert hall or on the venue.Couple of months ago my audiophile needed a help to fix his toilet, I came to help him. After Iam about leave, I requested him to play his system. He did, I stayed 3 hrs to enjoy the music , I’ve never experienced a system like that.It stops me from analyzing the sound, The performances of his system won’t let me, because I felt Iam inside the concert Hall.The system is Using Plinius sa100, Audio Research LS2 b preamp, Meridian CD player, I forgot his tt , I know it’s $500 with goldring cart and musical fidelity phono preamp, speaker cable Kimber 8ag, Speakers B&W 607 or 707? Interconnects Audioquest Columbia , And cobras.

There's probably a Nobel waiting for someone to show the inverse square law doesn't apply to sound from any source.

@dogberry In a line source when you are close to the speaker the sound you are hearing is coming from right in front of you. As you move further back, more of the driver(s) sound is able to reach your ears, so the sound pressure appears to not fall off as quickly. In fact its seems almost constant, but if you got far enough away (not possible in most rooms) you'd find that is obeying the inverse square law.

Years ago I built an OTL guitar amp that employed four 8" drivers snuggled as close together as possible in a vertical line. This was meant so that the musician wouldn't have to play seemingly quite so loud for the amp to project nicely and it worked quite well for that- you could hear the amp as easily at the front of the stage as you could in the rear of the club.

Dear @mijostyn  : That could be but here my speakers where you can read about. Please do it:

 

R.

@rauliruegas It might be a good idea to have the suspensions of the drivers renewed. Its hard to imagine drivers that old that are working right unless they are either all paper or use a latex-impregnated cloth surround.

I don't do the envy game, but I would love the L2030s.  Even via YouTube they sound spectacular.  

jayctoy, No one would argue with the positive experience you had listening to your friend's system, but in my opinion the system as described is very pedestrian for its day (late 90s to early 2000s) or any day, actually.  For one thing, my buddy owned an LS2B.  We both thought it was one of the least good sounding preamplifiers ever made by ARC. That's the nicest way I can put it.   I can say this to you I hope without personal insult, because it was not your system.  But this just goes to show us that there is pleasure to be had from even a set-up that would be considered mediocre at best by most.

Wow! Raul's speakers sound wonderful in those Youtube videos.  I'd love to hear a pair in person.

@rauliruegas , I down loaded the article and will get back to you on it. Cool Loudspeakers for sure. 

Tough call. Lots of folks say no way.  I am sure plenty arent fans of Klipsch speakers on here.  I would say the new Jubilees, which are huge by the way, can get you very close and I 100% refute the fact you need a lot of power.  Efficient speakers will bring you the detail you need at low volumes or high volumes.    Klipsch heritage line will give you a very realistic live soundstage and they love tube amps.    

K Horns , Cornwalls with a great matched amp set up I think many would be surprised how lifelike they are.

 

 

 

@rauliruegas , Back in the 80 ADS made what were arguably the best dynamic speakers on the market. The L2030s were landmark speakers in several respects. They used and active crossover and required bi amplification.  They used a line source midrange array. Cross over points are at 450 Hz and 4000 Hz. To orient people the wavelength of 450 Hz about 2.4 feet depending on altitude and barometric pressure. 4000 Hz about 3 inches. In order to radiate as a line source an array has to be as tall as the longest wavelength it is to reproduce. In this case  the mid range array is 30 inches tall so it does act as a line source over its entire range. The woofers and tweeter however are point source as the tweeter is 1" and the woofers are 30 inches total. This is unfortunately a distinct problem for amplitude response except at one distance from the loudspeaker. Point source acoustic power drops off at the cube of the distance while line source drops off at the square of the distance. This is why you always see line source arrays at big concerts. They radiate acoustic energy more effectively. In this case the midrange drivers are going to get relatively louder as distance increases creating a hump in the amplitude curve. They will sound "right" only at one distance. This can be adjusted to some degree by the crossover so you can probably tune them to a specific distance. The other problem is that point sources radiate differently than line sources. Point sources are more or less omnidirectional whereas Line sources do not radiate above or below the array. This is why the line sources you see at big concert are always curved. In this case if your head is either above or below the midrange array the midrange will virtually disappear.  The speaker as a whole should be treated acoustically like a point source system from a room treatment perspective. It is not highly directional as is a line source dipole.  

As a whole I think this speaker system should sound wonderful at a specific distance while in your chair. I am sure they are capable of wonderful bass however, since the woofers run up to 450 Hz which is a big chunk of the mid range (middle C is 256 Hz) these speakers will still benefit greatly from the addition of two subwoofers, two very big subwoofers. I would also exchange the cross over for s digital system. Check out the DEQX Pre 8 which will be released shortly. It has all the power you need and 4 crossovers! I plan on getting one to run a ribbon super tweeter from 12 kHz up and the subwoofer system. It will take the stress off the MA 2s from running the treble of ESLs. 

Dear @atmasphere  : Woofers are made of paper cones and the periphelical surround it I think is a very special rubber treated material. 

I'm original owner and I can tell you that if my memory does not foolish me the rubber suspension " feels " as the first day I own it at your sigth and when you move those woofers with your hand. Not scientific way but its quality perormance levels never gone dawn but the other way around because any change I made it to the speakers or my system is detected for the good or the bad at once.

Regarding the mid-ranges and tweeters the pheriphelical surround is paper and is impregnated of a " touchy sticky " solution.

 

R.

Dear @lewm  : Thank's, any time you are welcomed at my place.

 

R.

Dear @jetter : Yes , those vintage speakers are really good and mines are even better due to my self modifications that I next explain along a little history behind ADS and behind the L230s:

 

" A/D/S/ (Analog & Digital System) History

​

In 1966, a brilliant physicist, Dr. Godehard Guenther, came to the United states to work for NASA. Being an accomplished pianist and possessing an intensive passion for music, Dr. Guenther was disappointed with availability of high quality, cosmetically appealing audio products. He sent home for his Braun hi-fi system and soon his friend and co-workers were all asking if these products were available in the United States. He had Braun send a few systems and it quickly elevated to container loads. Godehard was awarded sole distribution right for Braun hi-fi in the United states.

​

Dr. Guenther left NASA and move to Cambridge, Massachusetts in 1974. He started importing drivers from Braun and Id the assembling and selling of the finished products in the United States. Eventually, he sourced all components and began designing and building his own products sold under the a/d/s/ name. "

 

So those drivers and specially the tweeter and main midrange domes are just unique an unavialable and ADS used only in two speaker models: L 2030 and L 1530. We just can’t believe that those vintage domes can performs with that so high quality levels, we can swear are today best top drivers.

 

Btw, latter on Ed Meitner was the chief engeneering and ADS electronics appeared as were the Atelier line and Museatux one. My L 2030 were designed by Mickey Kelly that gone out from ADS to start Aerial Acoustics till today.

The L-2030 " seen " the ligth thank’s to Telarc LP recording group whom talked with ADS to they build a custom made monitors under Telarc specs and that was what ADS did it and named BC 8/11 and was a full range bi-amp design that Telarc choosed to been handled by Threshold electronics. After started Telarc recordings the L-2030 appeared and Telarc used it along the 1530 too, always through Threshold electronics.

 

I bougth my pair with out knowing nothing about ADS speakers design and I bougth it at Metex Int. in Laredo, TX where I listened mated with Pioneer electronics , turntable and Denon cartridge.

The tweaks/changes to it started to damp internally those big boxes:

first it has " three hands " of a insulation/antivibrational treatment ( like a white paint. I can’t remember the ingredients. ) from Acoustical Magic Company ( it works marvelous ) and took me one full weeek to do it because I have to let dry that " paint " for the second and third hand and I had to take out all the speakers drivers to work with an empty box ( btw, both woofers are wired in parallel but each one in its own sealed space/compartiment. ).

At the same time I change the internal stock damping glass fiber by 10kg ( in each speaker ) of long hair 100% virgin wool and change too the fabric cloth of the grille for a " transparent one ".

It is internally hard wired with Silver Oval by Analysis Plus cable and KCAG by Kimber Kable.

In original stock condition the L-2030 came with some convenience swtichs: one to choose mid-range line source or point source operation, two others to change the SPL in the tweeter and mid-range by -1.5db to +1.5 db and the other switch was for overload protection.

Well, all those switchs just disappeared when I decided to make changes in the crossover:

I take out the crossover ( now is external ) and change all the parts: resistors ( Powertron by Vishay. ), all silver air core solid ribbon ( 5.5 cms. of pure silver. Almost 2kg. of silver in the bigest one. ) Alpha-Core inductors , WIMA FKP 1 and KEMET caps in the crossover, the speakers cables goes soldered directly to the crossover parts. This speaker crossover is tri-hard-wired from the amps output to the 3-way crossover parts and speaker drivers.

In reality are three separate/stand alone crossovers: one for the tweeter, one for the midrange and the other for the woofer, all these hard-wired directly to the amps ( no connectors. ). I added two Dalhquist external tweeters at the back of the speakers running with its own external crossover hard wired to each amp and with the crossover at 6.5khz and up

In the woofers " today " instead that the crossover been with the inductor alogn its caps I take out the caps and connected in series only the silver inductor with no caps.

From 4-5 months now the L-2030s re wired for point source operation and what can I say: just phenomenal/awesome. Yes, maybe you could be foolished by your ears listened to these speakers, even me because all the speakers surrounded system performs at the same quality level. No, it's not perfect, nothing it's.

Wired as point source permits that the inductor in the midrange could goes out ( the diagram says that ) but till today I did not because I preffer to mantain mid-range IMD as lower I can because with out the silver inductor the mid-range can goes deeper in frequency. Maybe some time I will test it.

 

These L-2030s runs from 80hz and up and the bass frequency is handled by two Velodyne active HGS-15 subwoofers that were modified too and where its woofers are made of paper as the L-2030. I do not change those subs because its very low THD at full power ( over 120db at 16hz. ) of only 0.5%. Subs crossed at 95hz.

These subs are just in front of the speakers looking in between face to face,

 

Btw, there is no additional external high pass crossover, this was solved internally on each Levinson 20.6 monoblock at its input with one FKP 1capacitor along a Vishay naked Z foil resistor.

 

@mijostyn I already check the DEQX and yes it’s a good option, thank’s.

 

R

 

 

@rauliruegas , see, you already had it all figured out! The subwoofers not only add bass but they clean up the midrange! It is important for people to know that. You certainly have a system capable of life like performance. 

@lewm , I went back to Sowter and they will make custom transformers. I drove the Acoustats with 100:1 transformers from 125 Hz up and it worked well. Right now I am crossing out of the stats at 100 Hz. I also am thinking about getting RAAL ribbon tweeters too cover 12 kHz up. I wonder if the bass transformer would handle that range or should I have 100 or 150:1 transformers made. The Plitron is too small. 

@rauliruegas Thanks for the history behind your fantastic speakers.  Since you mentioned Ed Meitner and Museatex I will put in a shameless plug for my amp and DAC, since nowadays no one really is aware of them.  I have the old Museatex Meitner MTR 101 monoblock amps and Meilor Museatex DAC subsequently modded by John Wright who use to work with Meitner.

Dear @jetter  : Good to know you own Mweitner designs, he was and is a very well regarded designer/manufacturer and I think that almost any audiophile read or knows some body that speaks about EMM Labs CD many years ago.

As a company Meitner still exist and doing fine.

Here some information of Meitner:

 

https://www.emmlabs.com/legacy.php

 

R.

@mijostyn  : Maybe even better than the JC1+ :

 

https://www.emmlabs.com/mtrx.php

 

R.

Mijo, You wrote, with reference to our SL speakers: "I went back to Sowter and they will make custom transformers. I drove the Acoustats with 100:1 transformers from 125 Hz up and it worked well. Right now I am crossing out of the stats at 100 Hz. I also am thinking about getting RAAL ribbon tweeters too cover 12 kHz up. I wonder if the bass transformer would handle that range or should I have 100 or 150:1 transformers made. The Plitron is too small."

My questions are with reference to your last two sentences.  What range are you talking about that you wonder whether the bass transformer could handle it?  If you are thinking about, say, 100Hz to 12kHz, I would say no.  One reason for my opinion is that when I measured the OEM bass transformer, it rolls itself off at or around 2kHz, probably due to self-inductance.  Another reason is that you need to keep in mind the effect of the ESL step-up on impedance seen by the amplifier is the converse of using a SUT with a phono cartridge.  The impedance seen by the driving amplifier is the intrinsic Z of the screen with no transformer divided by the square of the turns ratio.  So as you go up in frequency, a 1:250 turns ratio is going to result in a very low impedance for the amplifier, except as the self-inductance of the transformer seemed to dominate when I measured Z with the bass transformer alone driving the speaker.  Anyway, I would not be hopeful that this is a good idea.

And what makes you say the Plitron audio transformer is too "small"?  Have you ever seen the audio step-up transformers used by Martin-Logan and some other companies?  They ARE tiny, but SL use substantial transformers, and the Plitron 1:75 full range step up appears to be about the size, at least, of the OEM SL toroidal transformer they use for treble. Or is it the turns ratio (1:75) that you think is too small? To that I would only say that 1:90 of my Australian sourced transformer is excellent.  1:75 in terms of voltage is not that different, and because of the effect of the turns ratio on impedance (see above), Z at higher frequencies will be a bit higher than what I observe with a 1:90 ratio.  So it might be a trade-off with no untoward effects on perceived efficiency.  Anyone, like Intact Audio, who actually knows transformers is welcome to correct me on these generalizations.