You know the saying - If I had 5 cents for every time I was asked that ... then I'd be answering questions for a living. Anyhow, I have so much email from people asking about basic set up issues for the original Quads that I thought when I revamped the site that I would include this short section on just that topic. I hope those of you who have just 'discovered' this wonderful speaker can glean some use from these simple, but important comments below.
The original Quad was mounted, stock standard on three little oak legs, so that it stood about 4 inches from the floor. The idea, I am pretty sure, was to emphasise the bass response which really starts to taper off with a vengeance at about 40Hz. Of course, the size of your listening room has a great effect on this, and the larger the room, the less bass emphasis you would get in any case. The average English parlour is somewhat smaller than the average Australian lounge (by a bout 80%), and, I imagine, similar size differences would be the case in the USA. (Country gentleman who do not, and never did, "bangeth the head", and who needed more volume in their spacious residences simply bought 4 Quads, for stereo. AlistairRobertson-Aikman (SME) had 16 at one point!
So, what do you do? Well, in the average listening room of today, with wall-to-wall carpet, and various soft furnishings you should raise the speaker about 12 to 14 inches from the floor. This will give less apparent bass, but it is far more accurate, and this is particularly noticeable with male voice. Bass control of this speaker is exceptional, and they will produce real bass when asked.
Another very oft-asked question is: Should I mount the original Quad ESL (or the ‘63) off the floor? Closely followed by: “How high from the floor should I .....?”, and so forth. OK, for what it may be worth, my personal preference is to have stacked original Quads with the lower of the two speakers about 35.5cm (14 inches) from the floor. The base plate of the speaker stack is rather reflective (hard resin finish) - See SQ3 Pictures.
Additional opinions on the matter?
Tony Faulkner (Recording Engineer, interviewed 2003 for ‘Quad - The Closest Approach’ by Ken Kessler) said, “For my tastes, I prefer the sound with the speakers a foot or a little more off the floor, on open stands to tighten the bass.” He was commenting on the ESL ‘63 in this case.
Also commenting on the placement of the ESL ‘63, Peter Walker, in a letter to Ivor Humphreys (May 17, 1985) said: “I suspect they will be best raised well off the floor, much more than most commercial stands provide. Don’t worry about fancy spiked feet and the like, just prop them up on a stack of beer crates or what have you.” [reprinted in ‘Quad - The Closest Approach”, Ken Kessler, September, 2003]. In a recent email, Ivor Humphreys has reminded me that Peter Walker made the recommendation to put the ESL 63 up on beer crates specifically because Ivor was using them in an extremely small room, at the time, and that Peter had them "...in his own, admittedly large, room...placed directly on the floor". [Ivor Humphreys, Feb 18, 2018, private email communication]
These speakers like a certain amount of “space”, if you will. They should never, ever be placed close to, or parallel to, the rear wall, and they should be a minimum of 1.5 metres from the rear wall. If you want a "quick and dirty" recommendation - place each speaker about one third of the way along the diagonal of the room and you will be close to an optimum position, assuming your ceiling height isn't 25 feet, or something. Then, if you would like further improvements in the (already spectacular) imaging, use some kind of sound absorbing panels on the rear wall and tube traps in the corners and you will notice significant differences in the depth of the sound stage and the overall clarity of voices (for one thing).
For recommendations, see the Amplifiers page on this site. Also, use mono-bloc valve (tube) amplifiers if at all possible, and place them close to the speakers, using good quality interconnects to achieve this if you can. I use 7 metre long interconnects, and speaker cables (just heavy gauge copper) less than a metre in length. At that sort of distance, the 'esoteric' nature of your chosen speaker cable makes NO difference whatsoever to the sound. It has been said that you should use lower powered valve amplifiers, but this is not necessary, and if you want to use a more powerful valve amp, say of 50 Watts and over, go right ahead. I routinely use 65 and 100 Watt valve amps with my stacked Quads and I have not blown a panel yet. Yes, you can raise 'significant' SPLs, and I have had them up to 100 and even 104 dB without arcing. However, I wouldn't use this sort of level for regular listening - ever!!
The Felt Matting
All jokes about some “coarse mating on the floor” aside, I am often asked about the jute mats that are mounted behind the panels on the rear grille. The question is: “Should I remove them?” The answer to this depends (like most things Hi-Fi) on where you listen. If you listen in a small room, where you must keep the speaker relatively close to the rear wall (less than a metre) then you will have to leave them in there. If you don't do this, the rear wall reflections will bounce back just in time to smear the image irreparably. Also, in this speaker, if you listened at sufficiently high SPLs then you would stand a good chance of driving the treble panel diaphragms into their respective stators with too much reflected bass energy.
If you listen in a large space where it is possible to have the speakers well away from all the walls, but especially the rear wall, then you can remove the coarser mats from the rear grille. This will “expose” the bass panels, but you will see the treble panel (in the centre of the speaker) still has slightly denser, finer felt stuck on the back. Leave this in place! There is nothing to be gained by removing it! The acoustic load on the panel will drop off and the mid-bass information that the speaker delivers will be less precise. This felt, by the way is not mounted directly on the rear of the panel but is proud of the rear treble dust covers by about 5 millimetres. This means that a small "chamber" is actually formed at the rear of the panel, and this, plus the acoustic resistance of the felt itself, considerably increases the acoustic efficiency of the treble panel.
The speakers should have the treble panel centres "aimed" directly at each of the listener's ears. This is in both the vertical and horizontal dimensions. This is not a particularly "social" speaker in terms of the so-called "sweet spot". When you have the "aiming" correct in both planes, you will know you have it right. The sound stage depth will be huge and the placement of performers within the sound stage will be pin-point accurate.
The acoustic treatment of the room can aid in the overall listening experience immensely, and I don't care whose speakers you're using! The Quads, being a co-sinusoidal radiator are not as affected by room placement as box speakers. They do not excite vertical or lateral resonances very much. However, there is the long-dimension resonance to deal with and perhaps the "deadening" of exterior acoustic interference to consider. Polyester panels and tube traps can help. DIY these need not cost very much. Ordinary roof insulation batting will do nicely. I do not recommend fibreglass because of the fibre hazard it presents. You can see these types of acoustic treatment on this site - My Quads.