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ANATOMY of a WORLD-CLASS AUDIO-SYSTEM, Pt. 2:

The REVIEW of the 'Double-Autograph Tannoy' Audio-System

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Recently, I was contacted by a reader, Chris T, from South Africa. Here's how he first introduced his truly outstanding system;

"50 plus years of hi-fi. Biased towards horns and valves (tubes) but use mainly a Tact semi-digital amp at the moment. I agree totally with your comments about realism in reproducing music and how to achieve it.

I also am a fervent DIY'er and a great deal of my equipment has been self made. The picture of part of my speaker system is an adaptation of the Tannoy Autograph but with 2 X 15" dual concentrics and much heavier cabinet walls coupled with additional ribbon drivers to add to the mids and treble plus a super tweeter. Sub woofer is just as extreme."

Just imagine having such a system, in such a room, at your disposal.

Part 1, The Preamble to the review, is here. And Part 3, The Thread of our correspondence, before and shortly after the review, is also here.

Without further ado, here is;

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The Review (Double-Autograph Tannoy Audio-System)

By Chris T.

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First a bit of background. I have been a HiFi nut for more than 45 years. First amp was a mono Geloso valve amp which destroyed a Phillips 12” speaker the first time I tried it. Amps over the years included Leak, Quad, Radford, Pioneer and absolutely terrible transistor home brew. Speakers were Goodmans Axiom's 12” which I used until the Tannoy bug bit around 10 years ago. Cabinets for the Goodmans included everything from Bass Reflex to concrete sewer pipes (NOT pre-used) to replicas of the Decca Horn cabinet amongst others. I still own a pristine pair of Goodman Tri-axiom speakers although I doubt if my son who is using them will ever give them back.

My wife's hobby (life?) is horses so we stay on a 5 acre small holding. When we bought the place one of the good things from my point was an outbuilding that I converted into my music room and radio shack as at the time I was very into Ham radio. Things and interests change and the outbuilding has morphed into a single room.

Length    Width     Area       Ceiling         Volume

50'           26'      1,300sq'      ave 15'           20,000sq'

The room has a ceiling that overall slopes on the short side and steps up from  9' to 18' over the organ chamber on the long. The listening area is almost square at 26' with a solid partitioned of space for working in. All the funny angles seem to help with the acoustics. 

In trying to reproduce as faithfully as possible a musical event, all sorts of compromises, out of necessity, have to be made. The biggest of these surely is the size of the room one has to work with along with its concomitant shape. I have seen remarked that as audiophiles get older, the music they listen to changes, the end being chamber music. I wonder how much room size limits most of us.

Music to my mind consists of a number of components. Pitch, timbre, attack, dynamics, rhythm and melody. A good hifi should be able to reproduce all of these things. How well the system does this, defines the overall success of the effort. There are things that the audiophile finds important also such as the sound stage, front to back and side to side placement of the instruments and also information on the acoustics of the venue but these should be of lesser importance. However, more and more, these attributes have become the prime. 

Gilbert Briggs of Wharfedale demonstrated years ago that reproducing actual live music in the Royal Festival Hall, London and Carnegie Hall, New York was viable. Both of these venues seat upwards of two thousand people yet with basic amplification, some 20 watts per speaker supplied by Peter Walker of Quad amplifier fame and a couple of 12" speakers in rudimentary cabinets Briggs was able to, not only reproduce the live orchestra, but to do so in such a way as to demonstrate that there was very little if any perceived difference in the live to reproduced sound. The organ of the Festival Hall gave him more trouble, mainly in the deep bass.

 The system described below is the result of an evolutionary process which has been going on for over 50 years. In part I have been lucky by being at the right place at the proverbial right time, for some of my equipment I would not have been able to afford otherwise. My background in audio and far more importantly how instruments work and sound, I owe in very large part to my best friend who, until he died, played all of the wind instruments, brass and woodwind, all keyboard from organ to piano, harpsichord to harmonium. He also could make, in his words, a noise on all of the string instruments. He was also responsible for training my ear and in doing so proved that perfect pitch can be learned although it helps if you get issued with it at birth!

 The detail in a musical performance to a great extent depends on how far you are from the action and many recordings are unnatural in their presence or other odd features. A prime example is the von Karajan/Cochereau DGG recording of the Saint-Saens Symphony No. 3, Organ. It starts, in the very dry acoustic of the Berlin Symphony Concert Hall, with no reverberation at all, just as von Karajan liked it and it sounds wonderful. The second part of the first movement is a bit odd with more air. The first part of second movement is back to normal. Then comes the famous organ entry, along with the eight second reverb of Notre-Dame Cathedral. From no reverberation to 8 seconds! One bar to the next. Another example is a recording of a trumpeter with a burble in the softer sounds (usual cause of burble is false teeth) in a Brass Band. In real life this would not be apparent as no one listens to a band up close. I have heard this phenomenon when recording band music and the cure is to move the microphones back as it is not a genuine feature of brass sound. Only that the poor sod playing has false teeth. Another of the more favorite "details" that seem to be wanted is the sound a hiss a bow makes on the strings of a violin or any string instrument. In a close miked solo I would accept it but not in a full orchestra. Assuming one sits in the front row maybe some bowing noise from the string sections can be heard but that hiss disappears as soon as there are other sounds from the orchestra. Recordings that are mixed down from multiple mikes suffer from these noises which are from my point of view, an aberration.

The rationale behind the comments on recordings I have made and will make, in part define what I want my system to do for me, reproduction wise. 

For nearly forty years I used 12" Goodman speakers in rear horn loaded cabinets with separate horns for treble and midrange. The Goodman were around 100dB @ 1 watt which is easy to match with the normal pressure loaded mid and treble horns but there was always something not quite right. 


: Decca Horns face into the corner         Altec Horn with HF Driver      Tannoy Autograph 

About 15 years ago our national broadcaster started to "upgrade" and by chance I was able to acquire 10 pairs of Tannoy 15" Dual Concentric drivers in studio cabinets at stupidly low prices. All of the drivers had recently been serviced so in essence were as new. The choice of cabinet was never in doubt and plans for the Autograph were sourced and someone mad enough to tackle the construction found. The finished loudspeakers were manhandled into my listening room and voids filled with silica sand. Each cabinet weighs in excess of 300 pounds plus another 140 pounds of sand. These are the ones shown above. Almost heaven.

 An audiophile friend, after listening to the Autographs, made a suggestion. If I built him a pair of Autographs he, in turn, would build me a pair of 300B monoblock amplifiers with fancy output transformers and Serafine Silverfoil caps. As he is the South African valve fundi, this was an offer usually made by a mafia don. To digress for a bit. At that time I was experimenting with interconnects and had to hand, enough Silver wire needed to construct the monoblocks. More on the interconnects later.

 Through this same friend I was introduced to another slightly mad audio-type. This man, a medical doctor, a few years earlier developed an interest in using sound in healing but had problems with sound purity. This led him into a very long and judging by the many hundreds of prototype speakers in his workshop, winding road to the finest of ribbon speakers. One thing that sticks in my memory of the evening I met him, was his aversion to Neodymium magnets in speakers and that purity of sound is achieved only with Samariam Cobalt magnets. Negotiations ensued and he agreed to build for me, 2 per side mid range, treble and super tweeters using Cobalt magnets, 100dB @ 1 watt and 16 Ohm impedance. Of necessity the last with a transformer as the natural impedance a ribbon is around 1 Ohm. These run with no crossover as such, only caps to limit the bass going to them or to put it differently full range with the natural roll off of the ribbons to help to blend in with the Tannoys. When the ribbons arrived they were connected up with all the drivers in parallel and for the first time in my life I had a speaker system that was as near to right as I could discern. After tweaking the caps a bit and experimenting with damping behind the ribbons and trying horns on their fronts I went back to open front and back and no horns. Vertical ribbons have very wide sideways dispersion and very poor vertical so they are angled down so they are at right angle to the listening position.

 To back up a bit. After building up the set of Autographs for my friend he and I went to visit another audiophile who has just imported a pair of Tannoy Westminster Royal SE's which he was driving with Conrad Johnson amps. On our way home we discussed the Westminsters an we both felt that the Autographs sounded better. The Westminsters were developed from the Autographs, probably to make them more user friendly as the Autographs are corner speakers and quite imposing. Another set were built and sent to the UK a maker of violins.

About this time I had installed a pipe organ in my listening room which first had to be enlarged. Did I mention that I may not be strictly called sane? That aside the organ was great help to compare how far along the road to high fidelity I had come. The biggest niggle was that there was not quite the same degree of energisation of the room by the Autographs. The answer lay in a redesign of the Autographs to allow the fitting of another 15" drive unit. This brought the height to 6' plus the ribbons to just over 7.5'!  At the same time the wall thickness was upped to 1.3" from the original 0.5" called for by Tannoy. Also I moved away from plywood to high density pressed fiberwood. A modification I had made to the original Autographs was the addition of extra panels on the rear sides and I carried this through onto the new cabinets which brought the backs to 2" thick. The side exits of the horns (two per cabinet) were also enlarged which improved the bass extension a bit. The originals were quoted as flat +-3dB down to 20Hz. Again the drivers are run in parallel. The Tannoy Monitor Gold's which I am using are quoted at 30 watts RMS and have AlNiCo magnets. Using the monoblocks (SE, 2 X 300B's in parallel per side) and around 12 watts each and being stupid with the volume control, I have measured 106dB at the listening position, some 20' back from the speakers. Which is almost exactly what the organ measures when all the stops are drawn.

One hassle is that single ended valve amplifiers are not at their best with organ bass. Again by chance I went to listen to a set of French Waterfall speakers with glass cabinets and something in the amplifier, CD player and speaker chain stood out as being right. Definitely not the speakers though. It turned out to be the amplifier which went home with me. Cheapest in the TacT range, the SADI 2175 Semi Digital (now Lyingdorff) does something I have never heard in an amplifier before. It has absolutely no sound of its own. The reviews of it are all good if that's anything to go by. Claimed 200 watts RMS into 8 Ohms. The most disconcerting thing other than the lack of its own sound is the volume control. Unlike every other amplifier I have owned, increase the volume and it just gets louder, no distortion, just louder. The Semi Digital bit means analog pre-amp and PWM or Class D main. 

One more part to the speaker story with explanation or justification as you prefer. I am interested in organ music and that is the reason for all my HiFi excesses. Unlike any other musical instrument and including electronic organs with multiple speakers, a pipe organ energizes the space that it is in. This is probably because there are many, many noise making pipes spread over a large area plus the very low tones that fill a space like no other instrument. Usually an organ is designed to fill a reverberant space such as a church or cathedral with lots of stone work to bounce sound off. At the other extreme is for example, the Boardwalk Auditorium in Atlantic City and it's very large organ with more than 33, 000 pipes and an 8 second reverberation time. In the middle, a concert hall such the Davies Symphony Hall in San Francisco which needs acoustic sails to modify the sound depending on whether a small work is being performed or someone is bashing the organ. By the way, only one organ that I know of was designed with stereo in mind, the organ in the Royal Festival Hall, London and did they ever have fun with the acoustics there. Back to the organ and specifically the bass. Without a long dissertation suffice it to say that the lowest note commonly directly generated by an organ pipe is 16Hz. By various tricks however very many organs can actually deliver notes an octave lower and that means 8Hz. A handful of organs have pipes that sound a fundamental tone at 8Hz, the Atlantic City organ is one of them. That pipe is 64' long. It can also via the tricks department, deliver notes down to 4Hz.

 Most audiophile systems have sub-woofers to go down low but very, very few have meaningful output below 20Hz. Think of it from this point. The bottom Open Wood 32' C pipe in Liverpool Cathedral is 32' tall and more than three foot wide in it's mouth with a quarter inch gap for air to flow through at a pressure of 4.5" of water. The quantity of air shifted through the pipe past the languid is immense and no little sub-woofer is going to cut it. So what will? Firstly the room needs to be big, a half wavelength at 16Hz is around 35'. Secondly to move large amounts of air large cones are necessary. Tuned cabinets at these frequencies are difficult because when you get the fundamental right the partials or harmonics are at the wrong volume. My organ has three electronic voices (ranks) and I needed 3 different amplifier / cabinets to cope. And they could only play one note at a time without distortion. The port size is the same as an A3 piece of paper and is "out of tune" for the top 5 notes of the octave.

 My sub-woofer solution is a tube 25" X 25" square (is around 580 sq inches) and 20' long.                                     

This is closed at one end and has 4 X 18" drivers mounted. The other end                                             
has the best part of a roll of Dacron stuffed in it. The speakers are driven                                              
by a 350 watt mosfet amp. The speakers are rated at 96db/watt so possibly 
they will come up to 99dB as they are wired series / parallel.

 

Details of the system; components/rack & speakers:

Triode monoblocks 300B valves in parallel or                                                                                                                               TacT SDAI 2175 Semi Digital.                                                                
Generic 350 watt mosfet for sub-woofer.
CD Jolida CD100, valve output.
Otari MX-5050 reel to reel tape deck.
EMT 948 turntable
Jolida JD 9 phono stage
Blue Angel Mantis cartridge.
Squeezebox Touch and 1 TByte hard drive driven directly from Squeezebox.
DIY Ultrasonic record cleaner with separate rinse and vacuum unit.
Double Tannoy Autograph rear loaded horns. 2 X 15" Dual Concentric drivers per side.
Ribbon Tweeter, Mid Range and Super Tweeters.
All interconnecting cables are from 9999 Silver wire 0.7mm thick. One set as per Alpha Core Goetz Silver ribbon cables, Teflon dielectric.
All speaker internal wiring from the same Silver wire.
Main speaker cable. Twin core. 360 strands per core. OFC when new. Now 30 years old.
Mains. The room has a 3 phase supply and other than arranging that the air conditioner and lighting were on different phases and building a bus bar system 
to connect to, no other steps were taken. None of the equipment has anything fancy in the way of supply leads.

A small comment on interconnects. Anyone perusing information on resistance in wires will soon conclude that there is no magic material to be had. The metal with the least resistance normally available is Silver and with that in mind I acquired some. I wanted to try the Goetz type and rolled down some of the wire to thin ribbons (as per the details on the Alpha Core website) and put together a 1 meter pair. They do sound "different" from more conventionally constructed types but this "difference" is probably due to the extra capacitance which is part of the construction. I just love the name for the special insulating coating of the cables. A "Polymer of Terephthalate" or more correctly Polyethylene Terephthalate. Which is what plastic milk bottles are made from. Not very uplifting is it? And I mean $$$$ to be uplifted from my pocket.

How does it all sound? I mentioned earlier that a pair of Autographs had been sent to the UK and the recipient made violins. A couple of years down the line he visited me in South Africa and brought with him two violins. I recorded him playing one in my listening room and after playing the result back a couple of times he stood between the speakers and played along for a while. Then he started playing a different tune and when I queried this he replied to the effect that he could hear no difference when playing the same tune as had been recorded and only when playing something different could he tell what was live and what had been recorded. This experience has been repeated with a trumpet player, a pianist (on an old pianola which was being restored) and an organist. The organ was the least successful although this was before the Double Tannoys. So for small and single instruments the sound is almost totally realistic. For orchestral music memory of an event must serve as a guide.

I have a number of recordings of concerts that I attended and within the limitations of the recordings they are very realistic. Some years ago a friend who is also an organ builder spent three weeks, working and sleeping, in the Johannesburg City Hall, to ready the organ for a concert there, the first in many years. The concert went off very well and the conductor, who also runs a recording business, duly brought out a CD. I had, a copy of the direct recording before mastering and also the "finished" version. The CD as sold was very like most recordings, very clear, perfect balance organ to orchestra although as usual the brass had been toned down along with the organ. The sound of the venue was almost gone as well. Playing back the original and unaltered recording was revelation. Everything was as I remembered it and the sound signature of the City Hall, which I know well, was restored. As an indication of the resolving (which is a very poor term) ability of my hifi it is easy to identify a recording venue or ambience provided one has actually been there. My organ builder friend and I spent an evening with me trying to catch him out with recordings of organs he had either worked on or had helped install. His apprenticeship was with a very well known American organ building firm. His success rate was almost 100% and a lot of the his clues came from the venue. This despite the efforts of recording engineers, no doubt today, with rings in strange places and odd hair.

 I place great emphasis on a hifi being able to reproduce the actual sound of something. If a well recorded cymbal is struck it sounds real, likewise a triangle. Drums are also a severe test for a system as they have everything from attack to huge harmonic range to an equally large dynamic rage. The speakers reproduce this faithfully even huge orchestral crescendos such as found in the Manfred Symphony. Something I have not mentioned is that apart from there being two 15" drivers per side and horn loaded, each driver has a separate, pressure loaded, high frequency horn driver in it. For non Tannoy types this is the basis of the Dual Concentric Tannoy and it is every bit as good as the Altec version. Tannoy use the main cone as an extension of the HF horn. For what it's worth my take is that only the horn loading of the Tannoys gives them the speed to keep up with the ribbons. The size of the sound stage (yet another miserable term) is very big with the very large speaker cabinets set 24' apart. The listening position being 20' back. Because of the speaker height I have had to raise my chair 28" so that when looking at the speakers line of sight is midway between the main drivers.

 Again recordings differ, but using a good one for example, an old Decca LP with the d'Oyly Carte Opera Company's performance of the Mikado, and you are there. In corpus. Is it surprising that the Mercury recordings are so prized? Another one. An equally old recording of Ella Fitzgerald and the woman is standing between the speakers in my room. Level setting is paramount when listening for this sort of thing and what works for one track may not work for another I find. Many years ago I recorded  a session with my friend playing a Hammond M100 through a PR 40 Tone Cabinet and  a drummer (in a different room, the door being the volume control for the drummer) and the sound of the M100 comes through.  To anyone who has played  Hammonds they are all different sounding, model to model. Playing the recording back the M100 sounds as if it were in the room and this surely is another indication that the system is near right as could be. 

 Back to the organ. Bass on the organ is very complicated in real life and every commercial sub-woofer I have heard suffers from almost no definition. In fact most of them are almost one rumbling note. It is claimed that the ear bottoms out around 30Hz and this is mostly true of a sine wave but then music is not made from sine waves. All organ pipes have harmonic structures and those differ depending on what the organ builder constructs. Ignoring the reed tones, take the flue pipes. They can be open and made of wood, or metal, they can be half length with a stopper in them, they can have a bridge in front of the mouth, they can have two languids, the mouths can be leathered. They can vary in scale which is height to width ratio and they can be sounded in combination. To confuse further a normal organ building "trick" is to make a "virtual" or harmonic bass by means of a quint. Play a note and another a fith above and a harmonic sounds an octave lower at half volume. If you look at an organ specification and see a Gravissima or Harmonic bass listed then this is a virtual bass. Much cheaper to build a 16' pipe and a 8' sounding together than one 32' long! All these types sound different just wait until the organist starts adding ranks together. Most of the various tones heard even on a very deep note have higher components but unless the fundamental is right the correct timbre is lost. In Ian Tracey's recordings in Liverpool Cathedral it is possible to exactly discern the stop drawn and as far as it is possible to remembered the actual sound of the pipes along with the sound of the space although much smaller is reproduced. After all my room is not 1,300 feet long.

As to how the Tannoys sound as compared to other speakers presents me with a problem as nothing I have ever heard comes even close other than the Tannoy Westminster Royals and those only in gross, certainly not in detail. The first Tannoy Kingdom is not even in the same class. If I compare the good parts, the mid range, of stacked Quad Electrostatic ESL-57 even then the Tannoys are better. Please don't mention Martin Logan, or the big Apogee ribbon speakers as both of them are so crippled in parts, again the lower mid range, that overall they are of no interest to me. Neither of those have anywhere near enough punch for true reproduction of brass, for example, never mind any serious orchestral work at more or less realistic volume. I have yet to hear someone with electrostatic speakers turn them up on any source material - to me they are high priced barbecue grids.

There have been ONLY other two speaker systems I have ever heard that had the detail, dynamic response, tonality and clarity that I want. The one was a mono system with an Altec version of the Dual Concentric. The other was a very large Bozak system. And the Bozak was so long ago there may be colouration in my memory. I have never heard Wilson speakers but audio type friends have said the Double Tannoys are better but, again, all of this is subjective. I do know that Japenese Kondo Drums played loud sound real, as does a kick drum or a timpani.  

There is a recording, Cantate Domino, which seems to be loved by some, that has been so dumbed down by the engineers that for people to actually like it they would have to play it on an equally dumbed down system.

What price High End Audio? And don't get me started on Reference Recordings either.

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