I have three pairs of KLH model 9 speakers. One pair is running in a small music room with a McIntosh MC274 MK IV using the 16 ohm taps. The preamplifier is an EICO ST84, a Thorens TD 160, a Marantz CD player and two OTARI MX 5050 tape machines. The cleanest sound is from the OTARI machines when I can find a good two track tape of classical music from the late 1950s. CDs are almost always reliable. This system shows the weaknesses of various records, tapes and CDs. Its bass sound probably does not go below 60 Hz but sounds very nice and the treble extends above normal hearing level. This speaker with this system is smooth in its frequency range and can play rock music at a moderate level but seems best with Jazz, country and classical music again at the moderate level. Since these speakers are so old I don’t dare try to play them loud so do not exceed 65db at 60 Hz using the Radio Shack sound meter. This system shows the weakness of records that were recorded digitally and then put to the analog source. They also show the weakness of CDs recorded with too much compression or limiters. The fullest sound to come from these speakers is records and two track tapes recorded with tube electronics and analog tape. Surprisingly CDs sound nice when they are either recorded digitally. I am constantly disappointed when I go to stereo stores and hear their systems and compare that sound to what is coming out of my small music room. I would be careful with these speakers as when I tried to use an EICO HF89 amplifier in the bridged mode at 100 watts the amplifiers became unstable. I have been able to run these speakers with 50 watt Heathkit W7A mono amplifiers. The Heathkit amplifiers use the EL34 tubes which have less bass but a more detailed midrange. However, even with the McIntosh amplifiers the midrange is still quite detailed but the bass goes lower. These speakers will sound very nice with a real good recording but will also expose a bad recording and are extremely unforgiving with these. I will never use digitally recorded records with this system. Direct to disk and analog recordings sound best.

My second system is a double pair of KLH model 9 speakers in my larger sound room powered with two McIntosh MC275 MKIV amplifiers, a Citation One preamplifier, a Thorens TD160 turntable, a CD player and two Revox A77 two track tape machines. Because of the double panel configuration the 8 ohm taps are used and the two amplifiers are run in the mono mode with 150 watts each. Using this configuration the bass seems to go down to 40 Hz and the treble a little higher as well. Again these speakers are not run higher than 67db at 60 Hz using the Radio Shack sound meter. Again they will show two track tapes and analog recording records at their best. CDs also sound good and it is easy to hear the difference between jazz recordings where all musicians are in the same room and when recorded separately and added to the tape recording. The spacing of the instruments in the room is different and the depth of music in the room is greater when a group is recorded all at once such a Chicago 17 analog recorded record. Again digitally recorded music and then added to a record does not sound good on this system. One fullest recording is sounds are a two track 7 ½ speed recording of music such as Ravel’s “Bolero”. Another recording which sounds nice is a Jack Jones tape at 7 ½ speed quarter track tape. However, both systems will show the dynamic range of ¼ track tape. I cannot even stand to listen to tape recorded with 3 ½ speed quarter track tape, 8 track or cassette prerecorded tapes. The industry sound got worse each time they went from the original two track tape source. This system again sounds a little fuller than the two speaker system and the Heathkit mono W7A amplifiers gave slightly better detail in the midrange but less with the extreme highs and lows. This system is extremely unforgiving of bad recordings so about two thirds of my records have to be played on my dynamic speaker systems because of the modern love of digitally recorded records. Again the McIntosh amplifiers are used because of their reliability and ability to handle the load requirements of these speakers. With this system I am again mostly disappointed with modern music systems that I hear in high end stores. One high end store once he had asked me about my personal music systems closed his store and went home. His store is regularly advertised in Stererophile and Absolute Sound and has extremely good equipment.

I will never forget the time forty years ago when I was stone-cold sober relaxing in a luxurious leather recliner (throne) in the center of an extreme audiophile's professionally constructed tomb-silent listening room. Heavy curtains backed by sound-absorbing materials surrounded much of the room and the numerous exclusive stereo components were stacked in a separate room behind a heavily carpeted access portal. The music selected was an intricate yet rapid-fire number by Janis Joplin backed by Big Brother and the Holding Company, whom I had earlier reveled in while squeezed together with hundreds at the edge of her concert stage.

The sounds produced by the four carefully arranged KLH 9 speakers were as no other I've heard in my life. Rather I should say the sounds reproduced by my ears and brain were pleasing beyond compare, certainly exceeding the live music heard earlier. The perception of sound was as though I was wearing the world's finest headphones, mixing her voice and individual instruments in the center of my head; yet it was more. The music also seemed to be detected from throughout a vortex of sound waves whirling within a soccer-ball sized cavity surrounding each of my ears. The sense of a material presence near my head made me believe I could feel its contours with my hands should I chose to do so.

The mixture of music and the participation in it of my ears and brain created more than a listening experience. It was a stunningly complete immersion in another dimension of audio and virtual tactile sensory perception that conjured up waves of emotions and cognitive awareness synchronized with the beat, the pulse, and the intangible mysterious language of the exquisite art known as music. My senses left my self aside as I became one with the now inner voice of Janis Joplin and the strings and keys enhancing her presence.

Oh KLH 9, unlike any of your kind, etching deep into my mind, lasting memory of a time, when my self was no longer mine. I thank you.

Just some added info on KLH Model Nines. I've noticed some info about them specifically their construction which is not correct. The Nines did have 10 "woofer" panels and 1 tweeter assembly. There were not "front" and "rear" panels as some would lead you to believe, all woofer panels where in the same plane. There was a perforated metal screen on the back, with an electrical connection on its base. There was a fine woven screen of cloth acting as a dust barrier on its inner surface. The audio and power supply transformers and associated electronics where embedded in a wax and was the can that bolted or screwed in to the rear of the base.
I ran these with Futterman H3a amps and was able to deliver high output from them. Julius Futterman had personally modified the amps to provide better performance with the nines than his stock design had given.

I currently use Sound-lab A3 but I still preferred the sound of the Nines over the A-3s in some areas.

robert diiorio / nyc

OK for those of you who love classic high performance audio equipment this is a fairly 'esoteric' system. This story goes back to the days when I wporked at the old (now gone) Audio Center in Houston back in 1965. Woody, our resident audiophile 'extremist' had laid some unbelievable story about electrostats on our store owner, JCR and had gotten him to contact the KLH rep and order 4 of the KLH model 9, 6 ft tall wonders. We already had a pair of the QUAD full range electrostats in the large demo soundroom from the previous year also.
When the 4, KLH 9's arrived Woody went ballistic and started running around calling his audio and college friends and spreading the news. He (as always)
wouldn't let anyone else touch the shipment and he personally opened the rather long awkward box that they were packed in. After feverishly moving them all over the soundroom he finally put them in a straight line 4 unit array with
the end units 'towed in' about 15 degrees on the same wall and in front of the K-Horns. His reasoning was that we wwere not really going to compare these to the K-horns anyway what with the huge disparity in efficiency and all (84 or 85 db at 1 meter at 1 watt on the 9's and 104 db at 1 w/1 meter on the K-horns). Anyway woody proceded to drag out an old 2 track Westminister open reel tape with a binaural recording of chamber music from Austria (I think). I was finishing up with a customer when he said 'Hey come listen to this...'

So I went in and there was this not too terribly loud ultra sweet and clear chamber quartet playing a little repetitive Bach thing with a Harpsichord so delicate you could just visualize the thing sitting there somewhere about 5 or 6 feet behind the array of model 9's. This was and still is (in my mind) the most realistic small chamber group reproduction I have ever heard. The only thing I have heard since that comes even close is my friend John's 6 foot tall early Magneplanar (1971) system.

Anyway, Woody was getting that look on his face and he wanted me to go up to the stockroom and help him carry down a pair of Marantz Model 9's, so I went with him. When we found them they were back in the reserved area where stuff waits for other items when it has already been sold. I said, hey man I don't want to get in trouble, these things are reserved for some doctor according to this Work Order. Woody said, "I can open them very carefully and tehn reseal them later so well that no one will ever be able to tell they have been opened.

So, as you havce already guessed, the model 9 Marantz amps did get opened and hooked up to the four model 9's. As I remeber we finally settled on using the 8 ohm tap after comparing different taps for a while. The KLH model 9's are fairly high in impedance (around 12-20 ohms depending on frequency according to measurement later with Bill's little 'Z' meter that he rigged up later). The model 9 stats have input transformers with a radical primary to secondary ratio to provide a match for these internally around 50K ohm electrostatic panels.
Remember though, these early stats were rated at 16 ohms and we 2 per channel in parallel.

Later Woody took one of the stats apart and we found 4 panels in each side. four in front and four in the rear. These speakers radiate both front and back and should be placed at least 3 to 5 fett from the nearest wall behind them. Actually Woody's placement for the four had them well out into the room at around 7 or 8 feet from the wall behind them. Woody went and pulled an extra pair of AR-3 bookshelf speakers out to run in parallel with the two that were already in the sound room and then the real comparisons began. The AR-3's were running on the McIntosh 275 most of the time but at one point we ran them on the Marantz model 9's in order to determine if the amp was playing any part in the huge difference we were hearing. The four AR-3's were, of course capable of reaching down at least one full octave below what the 'stat's' were doing which was pretty much limited to a 55 HZ low end limit even in the far back of the room where Woody tried them briefly with one pair sort of closer to the corners (didn't help the low end...in fact I thought the overall imaging was worse so we moved them back to the other side of the room in front of the K-horns again).

The low mid range on the AR-3's did have a slight hint of the 'boxy' sort of sound so typical of Acoustic Suspension systems. (later HP tests with B&K mic confirmed that the AR-3's had a 6 db deep hole in the curve at 120HZ but only about 1/5 of an octave wide so this is a relatively small effect. The upper mid range on the array of AR's was smooth and pleasing but there were some noticeable 'lobing' effects that you could notice if you stood at various positions around 6 feet away.

Granted, this is probably not a good overall listening position anyway but this was a critical comparison and we were trying to find out all that we could. The high end on the AR-3's was a little rougher and of course very limited in high end response compared to the Model 9 electrostats. The overall imaging on the KLH electrostats was superb with a 'seamless' really large image. We tried switching the model 9 Marantz amps over to triode mode and the AR's still seemed to work well. The electrostats had a slightly more 'airy' light sound in the mid range but were so severely underpowered in triode mode that we had to really watch the gain control on the Marantz model 7c preamp because the amps were very easy to drive into really mushy and raucous clipping. After all we are dealing with a 40 watt per channel setup in this mode with the lowest efficiency speaker system I had ever seen.

The high frequency range was easily the cleanest most delicate I had ever heard with well over an octave of added high end response above the AR-3's (later HP and B&K equipment tests confirnmed that the high end is extremely extended well beyond audibility on the stats (30KHZ +) Yes...we did compare a single pair of KLH 9's to the pair of Quad electrostats we already had. The Quads were very nice with bronze color metallic perforated grill and were shaped like (and looked like) the back seat on a 1930 Ford Model A car with a slight convex curve upward. The quads were only half as high but about twice as wide. The quads had low end limited to around 80-90 HZ but other wise sounded very nice.
(Yes we had tried these before with the Marantz 18 db/octave electronic Xovers in a bi amp configuration with AR-1W woofers. Too bad we didn't ahve that setup
to compare because I remember it being a very impressive but strange lookiong rig).

The quads were hooked up to a pair of 10 watt Quad mono tube amps. They played ever so slightly lower in level (1.5 db lower we later found) than the Model 9's on the Marantz 9 amp. You would expect the difference to be much greater than that. The Quad 'stats' did seem to be more reliable but we never sold very many even though they were far lower in price about 350.00 less per pair than the KLH 9's were. The strange and old appearance did seem to limit its appeal (and market).

On the KLH 9's, one lady customer that bought a pair later had laughed and told us that she had put the stats in a back room because her dog stayed in the living room by the big windows and would howl loudly if she played the model 9's in there. She said that it never did that on her old Bozaks. Over the years I have heard all sorts of stories about the KLH power supply that provided the 600 plus volts anode voltage for the aluminized mylar film stretched over front and back frames (it appears that these sort of got sickly with lower voltage after 6 or seven years of continuous use). The high humidity found down in coastal Texas near the Gulf of Mexico seems to really take its toll on the panels also with later complaints from customers living near the water about snapping and popping sounds, (like a garden bug zapper). We never had any complaints from customers about mosquitos though. I wonder if there was a connection?