@atmasphere , I should have phrased that differently. It is the SLs that do not like making bass. The MA 2's should be fine driving the SLs in the bass because the impedance is so high. I am not asking the MA 2's to drive 2 ohm subwoofers.
@rauliruegas , I had Velodyn subs for the better part of a decade. The surrounds corroded and they literally fell apart. I can not quote you figures but I do know that given appropriately large drivers in well constructed sealed enclosures distortion levels are easily under 0.5%. It is only when using smaller drivers in flimsy enclosures that distortion becomes a problem. An amplifier that has tight control over the driver like the JC 1s with their damping factor over 1000 will result in excellent performance far in excess of what any Class D plate amplifier can provide assuming a large driver in a well constructed enclosure of which there are very few. The Velodyns do not qualify as a well constructed enclosure. No commercial subwoofer excepting the Magico Q series qualifies. If you commission me I will build you a knock out set of subwoofers.
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As a 25 year user of an Atmasphere OTL, I can tell you that with these amps a failing tube signals its demise rather gently. But keeping them in open air for ventilation and in plain sight is a good idea.
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@rauliruegas Pardon me for continuing this sidebar.
@mijostyn I assume you will not be placing your new Atmasphere MA-2s under the floor as with the JC1s. While heat dissipation is important, I'm more thinking you will want to be able to keep an eye on the tubes. I did have a situation with a tube amp where if I had not been able to see a problem as it occurred the consequences would have been very unpleasant.
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the JC 1+ puts around 300 watts at 16 ohms and can handle even higher impedance with absolute aplomb.
@rauliruegas That amplifier is designed to operate as a voltage source. The Sound Lab has an impedance peak of about 30 Ohms in the bass. That means that if the JC-1 makes 300 Watts into 16 Ohms it will be a little bit more than half that into 30 Ohms. Being a voltage source, it will cut its power by half with each doubling of impedance.
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Dear @mijostyn : I think you builded your subwoofers that are digital controled in its parameters and I whish to know which is its THD at 120db SPL at 16hz-20hz.
In my Velodyne's ( sealed design ) its woofers are mated with a self powered amplifier that MEETS all the woffer characteristics along that the woofer is under self " inspection " around 16k times at each second and all those makes that its THD at almost full power been as low as 0.5%.
If you have not " something " that be checking in real time the subs THD then the JC 1+ is not the " best " option because that Parasound was not designed for subwoofers as your desing.
@atmasphere the JC 1+ puts around 300 watts at 16 ohms and can handle even higher impedance with absolute aplomb.
R.
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Their output impedance is on the high side but I am not using them to make low bass so, that is not important.
@mijostyn
The Sound Lab has its highest impedances in the bass region. That is why solid state amps struggle to drive them- they can't make the power. For the MA-2 though its a walk in the park- they play bass very well on that speaker!
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@rauliruegas, I suppose that makes both of us (without technical foundation). I am moving my JC 1s to subwoofer duty and had a choice between the JC 1+ and the Atma-Sphere MA 2s. Both amps have a reputation for excellent performance on SL speakers. I opted for the MA 2s. They are class A all the way and have a very fast slew rate. Their output impedance is on the high side but I am not using them to make low bass so, that is not important. I also like hand made in America. Atma-Sphere does a beautiful job wiring it's amplifiers.
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In the DIY community, Nichicon electrolytics are very highly regarded. Not a compromise at all compared to Vishay or CD. I use them and if I thought there was a better brand for a particular application I’d use that brand over Nichicon. The cost differential among different brands of electrolytic caps is trivial, now that Black Gate and Cerafine are defunct.
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Dear @mijostyn : " from a cost/performance ratio I will take the JC1+ any day. Is Meitner any better than John Curl? "
Well, Parasound builded at a specific market price and the build parts they used are good but not good enough. Example: Parasound used Nichicon elctrolytic filter caps instead say Vishay or Cornell Dubelier that are 50%+ higher in price but even with better quality performance levels. For the JC1+ price tag can’t be outperformed, agree with you. Btw, the 130/84 K monoblocks neither use Vishay/Cornell or even Kemet and looks more like Epcos/TDK or maybe Nichicon ! ? ! ? ?.
Meitner or JC ? I think both designers are different more than better one over the other, however and maybe because I own the legendary JC design in my system and already listened the Parasound mated with Sound Labs and big Dynaudio I could incline for JC but with no specific technical foundation.
R.
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@rauliruegas
That is true. Source was a very good vinyl rig. Don’t want to take that for granted.
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Dear @mapman : System that sounds so real it is easy to mistaken it is not live.
That's the thread tittle: SYSTEM is the key word and any amp is only one link in a very complex room/system chain.
Anyway, you can post whatever you want because you have the rigth to do it.
R.
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The Classic Audio room running off the Atmasphere Class D amps did a nice job of this today at CAF. Very smooth and natural. A small jazz ensemble recording including piano played in particular sounded very relaxed yet lifelike.
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Raul, You are right. I apologize to you and any others who were offended by my and Mijostyn's going off topic. It seemed to be permissible because no one else was trying to change the subject, back to the actual subject of the thread. But, dear sir, please also keep in mind that you do the same from time to time.
Mijo, I will take our conversation private from here on out.
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@lewm It was sort of iatrogenic. The processor was doing what it was programmed to do which was make the frequency response of the speaker flat. Because of that speaker's location there was a large dip in the high frequencies that the processor was correcting. I then poured the coal into that situation with very powerful amplifiers. New processors have programmable limits to keep such an event from happening. I corrected the problem by removing the window next to the speaker and replacing that brilliance control with a 500 watt resistor and a very large heat sink.
Sowter does not make toroids. I used a 1:100 transformer successfully on the Acoustats using the same set up. It was one of their standard ESL transformers at the time. They may help design transformers to suit. I do not know yet. Using a super tweeter next to 8 foot ESLs is sonically risky. I would prefer a 6 foot ribbon out of a Magneplanar which would be less likely to call attention to itself as the radiation characteristics are the same. Above 12 kHz I think the tweeter will likely be less obvious. With the new processor I'll have four independent crossovers and I can experiment with less expensive equipment before I go to town. I can buy used Maneplanars, get new tweeters with their serial numbers then sell them. Perhaps I can get the local Magneplanar store to wrench a pair out of the company. I'll figure something out. What else is a retired guy going to do?
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Dear @lewm : With all respect: I think that you posted this:
" This is perhaps not the place to discuss it, for fear of boring a few others...."
and seems now that you are just insisting with. You can follow doing but which is your target that could help us?
R.
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If memory serves me, you felt in the end that you had burned up your brilliance control because your equalizer was boosting the signal by 10 or 12 db at a frequency that was traveling through the brilliance control. So that was in medical parlance iatrogenic. A problem you can easily get around by ceasing to cause it. anyway, I am sorry to learn of the demise of Plitron. They made good stuff. Sowter is also a very good company, and I am sure they can do a good job as well. To my knowledge they make only EI type transformers. Is that still correct? My other point was that you are taking a shot in the dark as to whether a single transformer with a 1 to 100 step up ratio can adequately drive the panel at frequencies as low as 100 Hz with vigor to satisfying levels. I wonder about this because Although I did not measure the frequencies involved, my memory tells me that when I tried to drive the panel full range with my 1 to 90 transformer the response was unsatisfying at frequencies that went well above 100 Hz, at least up to 200 or 300 Hz or so However, one could argue that because you are taking the onus of driving very low frequencies away from the ESL transformer, perhaps it will perform better at the higher frequencies (above 100Hz) that will be required. Anyway, you will find out if you do this experiment. I personally would not add a tweeter to Soundlab ESL or any othe high quality ESL, but that’s just me.
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@lewm Plitron is no more. It was bought out by Noratel Canada. They do have a custom transformer department and will design transformers for audio use in larger lots. I doubt they would just build two, but who knows. If I remember correctly the 1:75 Plitron was good for 100 watts. I have much more power than that. Remember, I have already burned up a brilliance control. My old Sowters were good for 300 watts. If I do this the plan will be to use one transformer, straight up to power the SLs from 100 Hz to 12 kHz. This would get rid of the RC networks. Correct, all the crossovers will be digital handled by the soon the be released DEQX Pre8 which has the capability to do four 2 way crossovers. I will use a small class A amp to drive the tweeters which I will hang at ear level on the medial sides of the SLs. ESLs do not do the highest octave well, the diaphragm falls away from pistonic motion and starts vibrating haphazardly. Ribbons are perfect for this but again because of their very low impedance a transformer is required. The Magneplanar 20.7 tweeter would be perfect but they will not sell a pair separately. I would have to have the serial number of a pair to order replacements.
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What do you mean by "power"? I get that you want to play at high SPLs, but if you are going to use bass and high treble supplementation and probably roll off the response of the SL speakers with very steep slopes, given your penchant for digital crossovers, then why do you anticipate needing the transformer to take lots of power? Have you evaluated the specifications of the Plitron toroid, so as to form a basis for your belief they cannot be driven hard, or what? Anyway, I have no compulsion to dissuade you from your aim to use Sowter transformers. (1:100 would be technically more correct than 100:1, BTW.) Sowter certainly is well regarded, although I did not associate them with making audio step-up transformers to drive ESLs. Sure, go for it. My recommendation of Plitron was solely based on the idea of your driving the speaker with two transformers (one for bass and the other full range) and dumping the RC network in the process. However since you are venturing into the unknown, you might want to find a way to experiment with using a single 1:100 step-up before investing in a custom build of two of them. (Acoustats are not identical to SLs in terms of stator to diaphragm spacing and bias voltage, although using separate bass and treble transformers was originally the idea of Acoustat, borrowed by SL in the late 90s or so.)
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@rauliruegas , at $85K a pair I would hope so, but from a cost/performance ratio I will take the JC1+ any day. Is Meitner any better than John Curl? I do not know the answer to that question. At this point due to the reputation of the Atma-Sphere MA 2s driving my speakers. I am spending 1/2 that amount on them. We shall see how that works out. The JC 1s will be shifted to subwoofer duty.
@lewm , The Plitrons will not handle the power I plan on dishing out. I can have a pair of 100:1 Sowters made that will and I should think would do a dandy job of driving the SLs from 100 Hz to 12 kHz.
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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.
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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.
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@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.
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@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.
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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
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Dear @lewm : Thank's, any time you are welcomed at my place.
R.
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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.
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@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.
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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.
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@rauliruegas , I down loaded the article and will get back to you on it. Cool Loudspeakers for sure.
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Wow! Raul's speakers sound wonderful in those Youtube videos. I'd love to hear a pair in person.
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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.
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I don't do the envy game, but I would love the L2030s. Even via YouTube they sound spectacular.
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@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.
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Dear @mijostyn : That could be but here my speakers where you can read about. Please do it:
R.
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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.
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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.
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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.
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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.
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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.
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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.
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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.
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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.
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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
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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.
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@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.
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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.
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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
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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.
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@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?
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