Albert...The MG1.6 and models lower in the line don't use the ribbon. When I bought the MG1.6 I also auditioned the 3.6 but I decided that I really preferred the lower cost item. The "tweeter area has lighter conductors and (perhaps) thinner diaphram. A very simple 2-way crossover is used. I think, and others have also agreed, that there is better integration between woofer and tweeter sections because they share common technology, and of course there is no physical distance between them. Perhaps if my HF hearing had not deteriorated with age I would like the ribbons better.

If one likes the planar dispersion patern (and not eveyone does), and can tolerate the "ugly room divider look", Maggies are a very cost-effective alternative to electrostatics.

eldartford March 11, 2007 23:33

Interesting that you attribute the lack of a limited "sweet spot" to the line array configuration. I have always placed importance on this characteristic which my humble system also exhibits. My present speakers are Maggie MG1.6 which are commonly called "planar", but the truth is that their woofer area is 8 inches wide and 52 inches high, so it might be reasonable to consider it a line array. I have three in the front, and this may also contribute to the uniformity of the sound field throughout the room.

eldartford March 11, 2007 13:48

Albertporter..."Burst" is bad. Glad you made it.

eldartford February 24, 2007 04:37

Albertporter...In the quest for better digital recordings I don't think that higher resolution is the key. Agreed that 16 bit 44 KHz is a severe limitation. But 24 bit 96KHz (multichannel DVDA) is quite acceptable, and if you are content with stereo (which is all you get with vinyl) the sampling rate goes to 196KHz. It's hard to imagine that going faster than this would gain you anything.

eldartford June 23, 2006 02:21

Gregadd...Although I built my audio equipment area, and TT shelf as solidly as I could, in a wall that goes down to concrete in the cellar, I doubt that it could match the pier and granite slab on the job. A pool of mercury is very sensitive to vibration but I have no data for a comparison of mercury ripples vs phono pickup output. I do know that the Halcyonics servo'd isolation table really works, for less $ than the shipping cost of the granite slab.

What do you guys do about airborn (acoustic) vibration? Unless you use a vacuum platter the LP is like a drumskin and very sensitive to sound. The sonic effect is similar to microphonic tubes. Have you tested for it in the way I suggested above?

eldartford April 29, 2006 12:43

I used to have problems with vibration affecting my turntable, but these were solved by:
1. Installation in a solidly constructed equipment alcove in my living room.
2. Turntable with softly sprung platter/arm assembly, and arm that was balanced around all axes with downforce by a spring. (Empire 598 if you haven't guessed).
3. Present turntable has linear tracking servo'd arm, and also exhibits minimal sensitivity to vibration.

However, all of this is with respect to vibration transmitted from the base. My experience is that acoustic vibration applied to the vinyl remains a problem (for some music played loud). You can easily test for this by placing the stylus on a stationary LP, and playing loud music from another source such as a CD. Monitor the phono output while doing this. I do not have a vacuum turntable or even a record clamp that might help with this.

eldartford April 28, 2006 18:48

Zaikesman...Easy now! Mass does help. Of course that is why we had the pier and granite slab. For most purposes it was sufficient. Bear in mind that these test stations were in the same building where large machine tools were being used, so the environment was probably a lot worse than the typical home. Just the same, the vibration isolation provided by the Halcyonic table astonished everyone. We could even put it on the concrete floor of a lab (not on the granite slab) and still get good images off the mercury.

eldartford April 27, 2006 23:03

Albertporter...Don't fret about not having that pier and slab. In my work testing inertial guidance systems we had piers with two ton granite slabs on them, but when we tried to do critical optical measurements using a pool of mercury as a reflector ripples on the mercury surface were a big problem. The solution was to put the dish of mercury on a servo'd vibration isolation table (Halcyonic). In context of your system the cost of such a table would be trivial.

eldartford April 27, 2006 18:23

Audiospirit...Great loves, lost or otherwise, always seem to be high maintenance.

I "modified" the very simple X/O in my MG1.6 if you consider replacing coils and capacitors with like values to be modification. However I would be a bit leary of changing the basic X/O design, because the Maggie screen is a unique driver which is tuned by various weights and tensions, and may be carefully matched to a particular crossover circuit. Can you describe what's wrong with the stock MG3.6, and what you think could be done to improve it?

eldartford April 24, 2006 12:08

Albertporter...Bongiorno has audio credentials that warrant consideration of his arguments, even if you don't agree with all of them. I follow your postings, even if...never mind :-)

eldartford April 21, 2006 15:40

Gregadd...You are not alone in that belief, which is Bongiorno's point in his write up. You can find it on his website. Worth reading. FWIW my speakers are Maggies.

eldartford April 20, 2006 12:36

Albert...Thanks for the informative link. I had stupidly forgot the ribbon, which as is usual is operated as a dipole. As to the woofers, I wouldn't compare the six ports on the back to the twelve cones on the front. Speakers described as dipoles usually have cones front and back. But as you say the LF does tend to radiate in all directions regardless of which way the drivers face.

I recently read a write up by James Bongiorno regarding Loudspeaker basic design principles. He suggests that most manufacturers have got things backwards. He says that the LF should be dipolar, and the HF should be directional. It is usually the HF that they try to radiate in all directions, even going so far as to mount an "extra" tweeter on the back if the enclosure.

eldartford April 19, 2006 22:27

Albert...."the Dali is dipole". ??? Doesn't look that way to me. Can you explain?

eldartford April 19, 2006 18:31

Albertporter...Tubes do use high voltages which is why their power supplies tend to attract a load of dust. But 600 volts is nothing next to the CRT in a TV set, especially before regulators required reduction of X-ray emission. If my memory serves, 25-30 Kv was usual.

In your amp, for example, if the same part has failed twice there is likely to be a fault elsewhere that overstresses the part. Your repairman ought to study the schematic and consult with the factory people to review this issue.

eldartford February 25, 2006 23:34

Albertporter...What failed? As I am sure you know, tube amps are comparatively simple circuits and generally made of straightforward discrete components and should not require factory expertese to repair. The local shop should do fine. Back in the good old days I troubleshot and repaired many an amp without even having a schematic. Modern equipment is another story, what with all the tiny close-packed surface-mounted components. In the factory I doubt that they actually repair anything...just plug in a new circuit board.

eldartford February 25, 2006 21:40

Nrostov...What I meant is that existing CDs can always be easily copied. Not so easy with vinyl, unless you can be satisfied with a tape or CD copy.

eldartford February 17, 2006 18:47

A minor consideration, but copies of CDs will always be available even if the record companies disappear.

eldartford February 17, 2006 15:25

Gregadd...Don't forget that as a vinyl spinner you probably have a superior system all around, so you can't just play the guy sone LPs. Will you demo CDs and SACDs as well as LPs on your system?

eldartford February 10, 2006 23:01

Albertporter...Unfortunately in audio, as with most everything else, the people with the technical skills don't run the show. Managers and lawyers do. So I am not the guy to perfect digital audio. It would have to be someone with good connections to the industry, both the hardware and software sectors, and to performers. In depth experience with the finest analog equipment is also necessary.

Can you guess who might fit this descriptuion?

eldartford February 10, 2006 22:21

Albertporter...Your 2/8 posting suggested that you believe that a good digital system is possible, but not available at present. I agree. I myself can think of several approaches that would be better than what we have now, all within the present 24/96 bandwidth. But I am not in charge of designing this system. By the way, I think that your suggestion that 2 percent of the public are audiophiles is wildly optimistic! And only a subset of audiophiles prefer vinyl.

The mirror analogy hits you wrong if you are familiar with the latest astronomical telescope mirrors. Instead of making one large parabolic mirror (which is hard to make and keep perfect) multiple smaller mirrors (which are more nearly perfect and stable) are arrayed and their images synchronized. The resulting composite image is much better than can be obtained with a single mirror of equivalent light collecting power.

eldartford February 10, 2006 02:13

Existing digital material is already better than 98 percent of the systems it is played on, and improvement would therefore be, from the Sony/Philips point of view, a waste of time and money. I believe that, without going beyond 24bit 96 KHz, the addition of some data processing in the playback system could emulate whatever it is about vinyl that some folk like. Several decades ago Bob Carver demo'd his ability to make one of his SS amps sound like any other amp, including tube amps, by the insertion of a network specific to the target amp. I never heard this demo, but all reports were that it was successful.

eldartford February 09, 2006 03:24

Albert...I guess we have just about beaten this issue into the ground, but my final comment is that while, as you say, two amps may differ sonicly at the X/O frequency, I believe that the two drivers will have a much greater difference. Whether this difference is enough to mask the difference in the amps is the question remaining to me.

I look forward to your CES report.

eldartford January 02, 2006 15:12

Zaikesman...Your suggestion regarding the staightforward quality of the VTL amps affecting Albert's perception is plausible to me, although I bet that Albert will deny it. As a long time biamper I can tell you that there is also a psycological factor at work...it just "feels" right to use the same amps. Looks tidy too.

My subwoofer/Maggie test was originally devised to help me match the SPL, irrespective sonic character. Perhaps it is not clear to you that the test signal, white noise, does not change. The crossover frequency is what changes. The idea is to see if the SPL, and the spectrum displayed on my RTA, is affected by whether the subwoofers or the Maggies are delivering the sound in the 40 to 400 Hz range. It may surprise you to know that the MG 1.6 is very flat to 40 Hz, and my "subwoofer" system is good to 400 Hz or more. (It probably should be called a "cone driver woofer system").

You might ask why, if the Maggies respond well at LF, do I have the SW system? It has more to do with LF power than LF extension. The SW system makes me flat to 20 Hz, but it's real purpose is to shake the house when I play certain kinds of music, most notibly organ. For that type of music a crank the X/O frequency up to 200-300 Hz.

It is possible that the white noise sounds the same regardless of X/O setting in the 40-400 Hz range because the way it sounds is overwhelmingly determined by higher frequencies that are reproduced by the Maggies in either case. However the basic test approach is interesting and could be applied to woofer/tweeter matchning if the drivers had sufficient overlap in their frequency response.

eldartford January 01, 2006 17:06

Zaikesman...Thanks for the comments.

Yes, I would feel the same way about a dome tweeter.

I am a long time biamper although with advances in power amps I think that it rarely makes sense except for subwoofers. In the past it was often suggested that a solid state amp should ideally be used for the woofer, and a tube amp for the mid/tweeter, where less power is necessary and tube sonic characteristics are most evident.
Of course subwoofers are almost always driven by SS amps, even when the mains use tubes.

I may be destroying my own argument, but I do have an example of two very different speakers that are well matched...my subwoofer system (multiple 12" and 15" cones) and Maggie MG 1.6. I can apply a white noise signal and sweep the X/O frequency from 40 Hz to almost 400Hz with virtually no change in the sound. In other words, in the range of 40Hz to 400Hz the cone drivers and the Maggies sound the same. I was surprised to find this.

eldartford December 31, 2005 14:32

Albertporter...Thanks for the response. When at CES why don't you ask the Dali folk, not *whether* the amps need to be the same, but *why* the amps need to be the same. I cannot think of any technical reason.

eldartford December 31, 2005 01:31

Albert...I can understand the value of high powered amps...twelve drivers represent a lot of mass to get moving and/or control even before they start pushing air around. But I don't understand why the Hi and Lo amps need to be identical. Gain matching is surely necessary, although that could be provided in the X/O. The cone LF drivers and the ribbon HF driver are very different technology, and any small sonic differences between two quality amps of different manufacture would be trivial compared with the difference of sonic character for the two types of driver.

eldartford December 30, 2005 20:48

Albertporter...The tubes had the physical appearance of a 12AX7, although I am sure they were something else. They were mounted horizontally, and stuck out of the rack in the back.

The computer could handle the scientific work we did back then but finally had to be replaced because they also did Payroll on it. A computer used for payroll has to be highly reliable. You can't tell your employees that their checks will be a few days late because the computer is down.

eldartford December 14, 2005 05:40

Albertporter...An IBM computer with at least 2000 tubes was what GE Naval Ordnance Dept still used when I started work there in 1961. Input was punched cards. I was told that it would easily heat a house in the coldest New England winters.

In the area of imaging devices for military and space applications, tubes (vidicons) were preferable to solid state devices, (CCD) until quite recently because they are inherently able to survive radiation that would fry silicon.

eldartford December 14, 2005 03:50

Albertporter...Marchand still sells tube crossovers, and there are other manufacturers. Some description of your circuit would be of interest. What advantage do you see in using the 12 volt tubes?

Of course they go way back. My first experience with a line level crossover was one from a schematic in a magazine that I built into the chassis of a 20 watt Heathkit amp. About 1955. HF and LF X/O frequency were set by a couple of multi gang pots with the HF signal output to a little Craftsman 10 watt 6V6 amp that I bought for the purpose. It worked really well, and never gave me any problems. I quit using it when stereo was invented, and I used the 10 watt amp for the second channel.

eldartford December 13, 2005 02:36

Albertporter...I checked the website description of your Megalines speakers, and was surprised to find that they are a stacked set of three rather conventional (bass reflex enclosure) modules. Of course your custom designed electronic crossover is a different deal.

I am sure that they sound great, but my hunch is that what you are hearing is the inherent superiority of the line array configuration.

Do you get the catalog from Parts Express? On the cover of the latest one is a ten-driver plus ribbon-sting homebuilt speaker system that appears to be more than six feet tall. I first heard a line array about thirty years ago at Club Med in Martinique...it was an outdoor system using about ten eight-inch drivers. It sounded good then, and the design is still good today.

eldartford December 08, 2005 12:44

Albertporter...It has to do with Lugnut's unrelated comments, to which I feel entitled to a very brief response.

eldartford September 19, 2005 13:07

For the record, I have cleaned many many LPs.

With regard to surface noise, people should listen and decide for themselves. It would make sense to do this before investing many kilobucks.

eldartford September 18, 2005 23:46

Very beautiful. I notice that you listening room is about as unsymmetrical as any room could be, which is contrary to what most audiophiles strive for. My room is also very unsymmetrical (except the ceiling is flat). Seeing yours, I feel less guilty.

eldartford March 16, 2005 15:40

About the square wave as a test signal...its chief claim to fame is that it is very revealing of phase shift. If HF is shifted relative to LF the square becomes rounded. Now music is not a square wave, but I think that most will agree that phase integrity is one of the most important aspects of audio performance.

And, by the way, although your electronics may pump out beautiful square waves, few loudspeakers can reproduce it. The only one I know for sure (I have seen the scope photos) are the old OHM Walsh driver systems. And you could hear it.

eldartford December 31, 2004 18:57

Albertporter...I am impressed. But why didn't you just hire the orchestra to play at your place? Wouldn't it be cheaper?

eldartford November 06, 2004 14:35