Naim´s Julian Vereker i en intervju om CD-utveckling mm.
Hej.
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Good Afternoon, Chicago!
In August 1991, Naim Audio’s founder and Managing Director, Julian Vereker was interviewed by US broadcaster, Peter Sutheim. The transcript of that conversation provides a fascinating insight into the ideas, philosophies and events that have shaped Naim Audio and its products.
Peter Sutheim: Good afternoon. This is "On Fidelity", KWK's weekly program for audiophiles and music lovers. My name is Peter Sutheim and I'm pleased to welcome today as my guest, via the miracle of telephone, Julian Vereker who is the Managing Director and also the Founder of Naim Audio Ltd., a British firm that is well known for its electronics and which has also recently produced a loudspeaker.
Julian is in the United States for the Chicago Consumer Electronics Show, which took place just few days ago as I record this. He has agreed to talk with "On Fidelity" listeners about what new products the company offers, and I'm particularly interested in the CD player and the new loudspeaker.
Welcome, Julian.
Julian Vereker: Thank you very much.
PS: Can you tell me something about the CD player, about which I know almost nothing except that it costs a lot.
JV: The CD player has obviously a fairly long history as far as our company is concerned. We started thinking about digital about four years ago. We spent the time looking at other people's efforts in that direction and trying to work out why it is that people say "yeah well that's a very good CD player" and "it's pretty good for a CD player", and there's always this sort of excuse for a CD player, whereas before we would introduce a new product it has to be very good without any excuses as to where the sound comes from.
We wanted to try and find out what it was that made CD players sound like CD players and why they were different from most other analog sources. Very, very simply what we've done is to go in completely the opposite direction from any other high-end manufacturer of CD players. Pretty much everything we've done is the opposite. We started with Philips components and while most of the high-end people tend to say "ah well, Philips are not quite the thing", we found that their engineering was excellent, their technical explanation of the system was very good and this made it very easy for us to incorporate their mathematics and relationships into our computer models. This is what enabled us to actually make a player that sounds as good as any of the best analog players around. There are various other very important things which contribute to the way that our player sounds, probably the easiest thing is to explain it in five items.
PS: The suspension of the player you say, of the actual part that reads the disc?
JV: Yes, the actual transport, the turntable part of it. The suspension is a very important part and affects the way the servos work, and the servo is basically a small amplifier which moves some part of the player. You have three of them on a CD player; one which controls the speed the disc goes round, one which controls the position of the arm which holds the laser, and the other one which actually focuses the laser. So you've actually got forces going in three different directions, so the frequencies at which the suspension is mounted, and the Q — i.e., how bouncy it is — is part of the way in which the servos work.
We found that the way in which Philips described it didn't give you a clue as to how important that was, and as we approached the right frequencies and the right Q, so the current required to control the mechanical things reduced to a minimum; and so, of course, as the current reduces to a minimum, so the amount of interference on the other parts of the circuit reduces and that was a very important lesson.
PS: Can I intervene just for a moment here to ask a question? I'm beginning, I think, to gain a little insight into this but I'm not sure that I am and there may be listeners who are still stuck in the idea that what comes off the compact disc is a digital bit stream pure and simple and if it's correct it's correct and if ain't it ain't and it's all ones and zeros anyway so what does it matter; how can things like greater or less servo control and current requirements affect the sound of the music? Can you address that for a moment?
JV: Well, in fairly simple terms the signal that comes off the disc is actually basically an 11Mhz radio frequency. The amount of interference that you get to what's called the eye-pattern, which looks like the pupil of an eye on a scope, which is why it's called that ... the actual shape of that is very, very important and the amount of interference on it...
PS: What are you reading on the scope here ...
JV: It's just a visual picture ...
PS: Of what?
JV: ... of the data as it comes off the laser, from the pick up. And as I said it's RF, it's radio, so it goes all over the place and it can have jitter and it can have bits which become confusing. It's not just a simple pulse stream as you would imagine.
PS: Now it's essentially analog too, is it really like what you'd get through a computer modem — let's say a sort of frequency shift...
JV: It's that sort of thing. It's closer to that than it is to the way you would see it on a wire so to speak.
PS: Aha, okay.
JV: It's not like a stream of ones and noughts at all. Yeah, as you say it's far more like analog.
PS: Okay, that's an important thing for people to realise because that immediately opens up the possibility to analog kinds of interference affecting what you ultimately get to process later downstream.
JV: Yes, that's exactly it. There are other things which turn out to be really important, for example, the paint with which you paint the top surface of the player is as important as the suspension...
PS: What!
JV: The paint ...
PS: Yes, I know, I heard you ... but ... tell me about that.
JV: Well, if you have a laser busily reading the disc, there's obviously going to be quite a bit of reflection and scattering of the signal, and if it's reflected off anything back in phase with the signal that's going on it just mucks the signal up. And so all this business of having shiny and reflective surfaces makes the whole thing very much less good. And, ah, what one needs is a paint which absorbs the infra-red as completely as you can possibly manage.
PS: Hmmh ...which is not just flat black...
JV: Which is not just flat black.
PS: Ah.
JV: It's a very, very, in our case, a very high tech paint finish and it actually costs, just for that little tiny piece of paint, about $16.
PS: You're talking about inside the player now...
JV: Yes, inside the player.
PS: Not the external cosmetic finish?
JV: No, no this is just a little tiny piece of paint underneath where the disc is.
PS: Hah, I'll be darned.
JV: Yeah.
PS: Okay.
JV: All these things are in line with the way that all Naim products are designed, that the whole product has to be a complete entity that is only as good as the least good part. So you have to deal with every single aspect of the design right from one end through to the other.
PS: Yeah, well I suppose everybody claims to do that to some degree...
JV: When you just look at the shiny tops on a number of players around the place and you see that they don't deal with that one anyway.
PS: Inside you mean?
JV: Inside, obviously the drawer ones you can't help...
PS: Now I can't resist asking here whether this has some bearing on the various proprietary CD treatments the actual disc treatments like stop light and whatnot that purport to somehow affect the reflectivity or the refraction inside the disc etc, etc... Do you find that those are useful in some way?
JV: They certainly do affect the way the whole thing works. On our player, all of them without any exceptions at all... all the green pen things and stabilisers and bits and pieces that you put on the disc... all of those on our player seriously affect the sound quality adversely. And it's not subtle, it is clearly obvious. And there are other little gadgets which I believe are just coming on to the market which are little aperture controllers which go on top of the laser lens, which are supposed to deal with the scattering of the laser, and those also seriously affect the sound quality adversely.
PS: That's very interesting, and I mean as a kind of intuitive leap I would just say that, is that, assuming that that's true, I accept your word for it for the moment, that it's because you have engineered a system that in which things are so carefully balanced against each other that the introduction of something like that is really spurious and unbalances it.
JV: Yes, that's exactly it. We assume that what you would really want to do is take the disc out of the jewel case and pop it on and have a listen to the music, that you don't want to spend a few moments sticking something onto the back of it or putting a little rim around the edge of it or painting the thing green, you just want to take it out of the case and listen to the music.
PS: Right.
JV: Hi-fi for us is not a technological toy, it's something to listen to music with.
PS: Right, now, but you're not inferring from this that these treatments, these user CD treatments, are ineffective with other players.
JV: Absolutely not.
PS: Have you explored that at all, or is that you don't care?
JV: I have heard them used on other people's players and of the players that we've had in the factory and so on, they have made an appreciable difference. But to my ears they change it from one sort of not very nice to another sort of not very nice.
PS: Ahuh.
JV: Some of them you could say it was positive, but then I didn't care for the end result in any event.
PS: Ahuh, right. Now the result of all this is a player that you feel can truly hold its own beside real music or the sound of analog discs or what? How would you put that?
JV: Well, the way that we feel about it is that it's software limited, so that it depends how good the disc is. If, for example, you take a collection of albums and a collection of CDs and you play through them — actual matching pairs — we find that with about half of them the CD will sound better, and the other half the album will sound better, in musical terms, in the sense of musical enjoyment. Obviously it depends on what sort of music you listen to; it depends where you bought your albums and all those sorts of things. And it also depends how old the disc is because, in general, the more modern discs seem to be better and particularly the modern transcriptions of older music, sort of late '60's music and particularly the jazz things we've found, some of them are absolutely exceptional. Because they were recorded using simple techniques, pre-Dolby, so you've got a little tiny bit of tape hiss there which acts as a slight dither and the results can be quite extraordinary.
PS: I see, well fascinating ...
JV: By any standards that's not just in comparison with, you know, a particular record player.
PS: Well, alright, now you discovered that the physical properties of the actual transport, the disc reading mechanism are very important, have you covered all of...
JV: There's one other thing which we've done which I think is again pretty much the opposite of everything that everyone else does. There seems to be, particularly in audiophile transports, people putting heavy things onto the disc to hold the disc down and so called "damp" it. We in fact do exactly the opposite. We have the lightest possible clamp or puck to put on top of the disc which uses a neodymium magnet — very, very powerful rare earth type magnet — to clamp it down. And it's very light and the clamp is arranged so that it only couples the disc with defined frequency bandwidth so it's not coupled tightly the way that other people's clamps clamp the disc to the...
PS: Coupled to the transport mechanism itself, you mean?
JV: Yeah, because the motor, the actual turntable motor — and it's direct coupled, a direct drive — is being fed with all sorts of pulsing currents in order to keep it at the right speed and of course there's a lot of vibration. Now you feed that vibration straight into the disc, which again affects the clarity of the eye pattern. So what we do is to couple it at a frequency where you can drive the disc, but not so that all the energy from the motor is fed straight into the disc. Now obviously the tighter you clamp it to that the more vibration you're going to feed in there.
PS: Right.
JV: And so again it's sort of like taking the complete opposite view from the way that everybody else looks at it.
PS: Right, I'm reminded of a sort of analogous thing in loudspeakers were the notion often is to have drivers as small as possible for the frequency range that they'll handle so that the dispersion is very great and the other approach is to have large panels which can, subjectively at least, produce a very similar kind of sensation of the sound not coming from anywhere in particular, but just being there in the room, two very opposite approaches. Are there any other details about the transport?
JV: Well, Peter, the other thing is you can go steadily on down the line but the next big difference is the fact that we have the transport, all the digital circuitry and the analog all in the same box. There is no separate D to A box.
PS: Ah, okay now, this is interesting also because I have had some people suggest that the approach of having a transport with a separate converter in a separate box is not in fact a good idea. Have you found that to be true for a certain particular reason?
JV: I would say that you cannot make a really good player if you have those parts in separate boxes. Using the SP-DIF connection (which stands for Sony/Philips Digital Interface) that particular piece of circuitry and that particular way of doing it, I don't think that it's possible to make a decent sounding player having a separate box in that way. It may be possible if you use something like a 50Mhz bandwidth optical fibre, and a whole lot of other expensive technology to do a reasonable job, but I still don't think that even that is as good as having all those bits clustered around each other on the printed circuit board so you have control of all the references and the noise and jitter and all those sorts of things. It's really, it's sort of like designing a car and putting the engine in a trailer behind you.
PS: Well you know there are such apparent, at least on a superficial level, such contradictions here. Most audiophiles or even people very modestly acquainted with audio if you shake them awake at 4 o'clock in the morning and ask them which is better, receivers or separates, they would say separates of course without really knowing why, and yet that idea has really permeated the, what you might call the marketing layer of the business, and has carried over to some extent, maybe as it turns out completely spuriously, into the business of CD players. The idea that well it can't be any good if it's all in one box. The audiophile's constant pre-occupation with sort of making his or her own choices, not taking any one manufacturer's ideas as a whole. The idea of being able to have so and so's transport and whosies digital to analog processor is very appealing on some level that I think may actually stem from the idea that separate tuners and pre-amps and power amplifiers are necessary. And you are now debunking that sort of folk notion?
JV: Well, for example, would you consider buying an amplifier from one person and its power supply from somebody else?
PS: Well, probably not unless somebody could give me a very persuasive reason why I should.
JV: Generally speaking power amplifiers are just a power supply with a faucet (tap) on the end ... the amplifier is like a faucet ... just turn it on and off in time with the music, so the whole thing is like together. There are very, very few people and I can't think any audiophile or high-end companies that manufacture a power amplifier which comes in two separate boxes, one the power supply and one the amplifier. It's just not a sensible way of doing it, of putting that sort of uncertainty of a separate cable in between the power supply and the amplifier part of it.
PS: But many people do it with pre-amps and things of that sort...
JV: With pre-amps because you've got ... first of all it's a rather different thing, because a pre-amp tends to be a class A device, also concerned with very, very low voltages and currents and you really don't want to have the hum field being induced into the case of the pre-amplifier which is bound to be induced elsewhere into the circuitry. So I mean that is slightly different and also as long as the power supply is in the signal line between the pre-amp and the power amp you haven't actually lost anything in terms of reference. Where you do lose something is if you have the power supply sort of hanging on the thing separately and it's not in the signal line, i.e., you're not actually using the reference line of the power supply itself.
PS: Right, you're talking about in a power amplifier now.
JV: That's in a pre-amplifier.
PS: Oh, in a pre-amp, okay.
JV: But with our pre-amplifiers, you've got the power coming up a cable from the supply and the signal to the power amp goes through the power supply: i.e., it is referenced to the signal ground, the actual earth point in the pre-amp power supply. That's one of the reasons why some people's separate power supplies don't work terribly well because they've lost their reference. And that is a very important consideration.
PS: Right, I see, okay. Well getting back to CD players for the moment...
JV: To go back to the business of actually having the things together all in the same box, this goes to the extreme of not having a digital-out at all because all that circuitry tied up with the <nobr>SP-DIF</nobr> is not of audiophile quality we found.
PS: All that circuitry, you mean just to make it possible to have a separate digital output?
JV: That's right...
PS: I didn't know there was a lot of circuitry involved in that...
JV: It's just a little bit of a chip...
PS: You can't use that as a side chain in the same way that you might, let's say, put a buffer on a tape output on a pre-amp or something?
JV: Not at that particular point it doesn't seem to be a sensible thing to do from our experience.
PS: I see.
JV: That's not to say we'll never discover a way of doing it but we certainly haven't yet.
PS: I see.
JV: Then, going on from that, there was another sort of major part that we found. We've always been aware that vibration, airborne vibration from the music or anywhere else, affects the way that things sound, because all circuits are sensitive to a greater or lesser extent to airborne vibration. And on our 52 pre-amplifier, which we introduced last year, which is our top of the range pre-amplifier, we were very, very careful about how we attached the sensitive circuits into the pre-amplifier to make sure that the coupling was really low frequency and sub-sonic and there was no high frequency component to modulate the music. And on the CD player, the chips, not just the digital chips but also the analog ones, and the op-amps and the control circuitry, turned out to be nearly one thousand times more sensitive than the discrete circuits that we use in our pre-amplifiers. So we had to go to extraordinary lengths: instead of just attaching the board, the board itself is mounted on a sub-chassis, which is then suspended inside the player. So not only when you get the player do you have to actually unlock the transport part of it but you also have to unlock the suspension on the main printed circuit board.
PS: I'm beginning to remember how when digital was first introduced at a consumer level in the early 1980's the feeling was not only that really abominable slogan "perfect sound forever" but that it was all so simple and straightforward that for one thing the various amateur audio tweak publications and so on would essentially go out of business because all CD players would have to sound pretty much the same and there would be nothing left to do in terms of amateur engineering or modifying or anything like that because it was all very, very cut and dried.
JV: I remember that. Yeah, I think that probably did them the biggest disservice ever. I mean put the whole thing back about five years, by starting off with the perfect sound forever thing, because you know to people who were interested in music, you had one listen to it and it was quite clear that not only was it not perfect but it probably wouldn't be forever if it went on sounding like that.
PS: Right.
JV: And because one sort of took it at face value, if they think that it's perfect, fine let them get on with it. A lot of high-end people just turned their face against it, literally from day one. And I think that was probably a very, very damaging moment in the whole life of digital audio, and it certainly stopped us looking at it in any serious way for about five years.
PS: Really?
JV: Until we started hearing other people's attempts at digital, some of which sounded really different, and you could see why the approach that they had taken had ended with the result that they did. I'm not saying that any of these were acceptable to me, or to any of us at Naim, but nevertheless we became aware of real differences between various players and we asked a university research worker to have a look into systems to see whether one could do real time processing to actually fix the digital data stream up, you know after a mess had been made of it, because we assumed that what was on the discs was not very good. And research work at a French university had shown that what was on the disc was pretty much rubbish and so we started looking at alternative approaches. But that was literally five years after the launch of CD and if everybody had said "right this is a new thing and there are lots of possibilities to get it to sound good" we would have leapt straight in at the beginning. So I think that's a really good point, Peter.
PS: Fascinating. Well I don't know whether it makes sense to go through the rest of the circuitry detail.
JV: Well, there's only two very quick points more. One of course that always gets mentioned in all the magazines is the business of the output filters. The output filter on ours is probably no less complex than anybody else's but it's based on the linear phase filters, or the work that we have done on linear phase filters since about 1976 for active crossovers for our hi-fi systems, for our speakers. And so we had a lot of experience and a lot of really good computer models of how they work and so, in fact, once we perceived what we had to do it was relatively quick to actually do it and I don't think anybody is going to be reverse engineering that in a hurry.
The maths is fantastically complicated.
PS: I should mention for the benefit of listeners who don't know that term, that reverse engineering is when you buy a competitor's whatever it is, you know player or car or other device, and take it apart and figure out how they did it and whether you can do it more cheaply, that sort of thing.
JV: Yeah ...
PS: Where do you stand on another numbers game issue, the oversampling business?
JV: Well, the actual digital technology is not something which we actually talk about or specify, because I don't think that it makes any difference which system you use as long as the system that you pick actually works properly. And you could probably make a very good player, well I'm certain you could make a very good player, using 14-bit or 16-bit or 4-bit, one of the matching type systems, or even bit stream, one-bit. And I really don't think that it makes any difference: it's a bit like discussing with amplifiers whether it's class A or B or complimentary or quasi-complimentary or whatever. You know the technology itself really doesn't matter, it's the level to which you actually engineer all the other bits — well and those bits, they do need to be right.
PS: Hah, I see.
JV: And whilst our player is one thing at the moment, it may very well be something else later. And I would hate anybody to think that a particular piece of technology is actually the reason why it works ...
PS: Right
JV: ... because I would say it has nothing to do with it at all.
PS: So as far as you're concerned oversampling is really another one of those I dunno, red herrings or something that people...
JV: Pretty much.
PS: ... people chase after. I mean there's a tremendous desire to quantify everything, to put everything in terms of simple numbers, figures of merit and that kind of thing, and three-way systems have to be better than two-way systems and so on, and an amplifier with two hundred Watts per channel must be better than an amplifier with only a hundred Watts per channel, that kind of thing. I don't know if that's true in Great Britain as well, but it's certainly seems to be true in the United States. You can really sell stuff by simple numbers.
JV: It is true. Well, they're probably less certain in the States because the British companies have been saying for longer and have had more support from the magazines that, you know, the consumer should listen ...
PS: Yeah.
JV: ...and you know, the numbers never ever make up for the actual experience of going into a store and having a listen to various systems, and asking simple musical questions of the system, and making up your own mind. I know it's a responsibility to do it for yourself, but it's your money and it's your life.
PS: Yeah, there's always I think a persistent feeling on the part of a lot of consumers that a manufacturer or dealer who gives them that answer in response to the question "well, which is better?", is either ignorant or is trying to hide something. It's funny, it's a very persistent notion that somebody else ought to be able to tell you which one is the better of the two and ought to be able to tell you in simple terms like not this vague fuzzy stuff like, well does it make you tap your feet to the music or something of that kind, but is it four-times or any times oversampling?
JV: Yeah, em, I suppose the difficulty for me, is understanding the other point of view that, you know, if you read a book there is a story content, and then there's a way the English is written, and further there is the quality of the printing, the paper and so on, and you make up your own mind whether you like the book or not and by what criteria.
PS: Right.
JV: And it doesn't really matter what anyone else said about it, it's your own personal experience.
PS: But it does matter to a great many people.
JV: Well, music is only another language. I mean there's nothing magic about it, it's not that different from writing. It's the same sort of experience, and your brain interprets the both of them, it's not a matter of I haven't got very good eyes and therefore I can't understand English, you know, I haven't got very good ears...
PS: Right.
JV: ....it's to do with the brain.
PS: Bravo. Thank you for saying that. It's something I've tried to say many times on the programme. People call up from time to time, and they say "Well, I need a new pair of loudspeakers because mine are really falling apart and so on, but I'm sixty years old and my hearing isn't all that good anymore and I don't need anything very good."
Do you find that funny?
JV: Well, in a way. My experience is as I get older that you actually get better at doing those things ...
PS: Aahh ...
JV: ... not worse.
PS: Thank you. Well of course, because the total experience that you bring to it is greater and it's not just, as you say, it's not just a matter of frequency response, and whether you can or can't hear up to 16kHz and so on.
JV: It's nothing to do with the mechanics of it at all. I mean, you know if you come down to the very simple basics, em, on a telephone ... if you answer your telephone, and it's somebody you know, you'll probably recognise them just from hearing their intake of breath. By the time they've said a couple of words, not only are you absolutely certain who it is, but you also know what sort of mood they're in. There's a whole lot of stuff you can tell, and that is down a telephone line which only has a band width of 3kHz and a dynamic range of 34dB.
PS: There you are folks.
JV: Why is it that you can't tell those simple things on most hi-fi systems, about the musicians? You've no idea about the characters of them on most hi-fi systems.
PS: Right, well, of course some people might say that it doesn't really come through in the live music either. I don't know. I guess it depends on how sensitive a listener you are.
JV: It also depends how bad the PA is.
PS: That's true too, yeah. I was thinking about unamplified stuff.
JV: I mean one of the things about actually being over in Chicago, is that the city is full of live music. The first few days here I spent going out every night to various clubs and listening to musicians and a friend of mine doing some recordings. And, you know, you just shut your eyes and you can feel the people; you can feel what they are trying to say; you can feel them playing together; you can, you know, if you're watching of course you can tell, but one of the things about a hi-fi system is that you don't have the visual side. And I keep on asking myself, how much can you really tell when they're live. And you can certainly tell more than you can tell on any hi-fi system. You can tell if they turn to each other to, you know, like time the next little riff in or something rather, you know, it's all there, it's people communicating with each other. Only it's not words.
PS: Yeah.
JV: People somehow or another feel worried about it, and insecure about it. It's only a matter of experience — the more you do it the more sure, the more confident you become, about assessing those things.
PS: Yeah, that's a, yeah, I've a feeling that we are going to be playing back this conversation on the programme a number of times over the next year or so, because those are some very, very important points you're making that don't get made often enough in the commercial business of hi-fi. Which is extremely product and hardware oriented, not, not very much oriented in the direction that you're talking about, the listening experience. I mean lip service gets paid to that in the ads, em, "listen your ears will tell you" and so on, but God forbid that a customer should actually do that.
JV: Well if it was only the ears it would be a pretty boring thing.
PS: Right, well, that's just used as a metaphor, a simplifying metaphor. Well, this is most illuminating, I actually would like to continue in this vein but I think that we probably should take a look at the speakers also, if you're willing to go to that, to make that transition. I guess it goes without saying that the same design philosophy applies to the loudspeaker design.
JV: Absolutely. Oh, there's one last little point about the CD player just in case anybody should think that it is actually a one-box CD player — it isn't. It is a two-box CD player, but the other box is the power supply. Because one of the little things which happens in a CD player is that all the various circuits do talk to each other in a way that is not very desirable, mostly through the power supply, so there are nineteen separate supplies all of which have carefully matched bandwidth to control all the various aspects of the player.
PS: Wow, nineteen. Well there's a number somebody can grab onto. Hey, the new Naim CD player has nineteen power supplies, it must be better!
JV: But that is a factor which counts, and that is all in a separate box on the player.
PS: You mean it's physically separate, joined with a cable or ...?
JV: Joined with a cable.
PS: I see.
JV: There are actually, I think, 16 cores in the cable and there are some divisions which actually happen inside the player.
PS: Ahuh, right.
JV: This is like, em, we've been making speakers again. We used to make speakers from 1970 to 1976, and then we stopped making speakers and then we started again in 1986, with the SBL, which is a separate box loudspeaker. And the DBL is sort of like The Statement, our statement about loudspeakers. It's about four-feet high and about two-and-a-half-feet wide and just over a foot deep, but doesn't stick out from the wall very far, but it's a reasonable size cabinet. And the drive units ... it has a 15-inch bass unit, with a 3-inch voice coil and an enormous magnet. I mean truly enormous. And that is actually mounted in its own cabinet which sits on a stand which is part of the structure of the speaker. And it's coupled into a bass loading box through a precision acoustic resistance. This completely controls the fundamental resonance of the speakers, so if you try and measure it it's not there.
PS: Uhuh.
JV: Which means that although the speaker doesn't have a flat frequency response below say 17 or 18Hz, the response does go down and the distortion doesn't increase above 1% until you get down to 8Hz.
PS: My, my.
JV: So you basically have a speaker which knows where to start from ... you know, so that notes begin properly ... you know, a piano sounds like a piano ... you can just feel the notes being struck. Many speakers get that sort of impression by having a sort of peaky response someway or another to try and get some brightness and life into it but this has a substantially flat frequency response and we get it from actually doing everything very, very carefully. One of the other things, of course, is when you have an enormous great drive unit like that you have quite a lot of moving mass and so you tend to put a lot of energy into the cabinet.
PS: Right.
JV: So what the traditional way of doing it is, is that you make a very rigid cabinet so it doesn't move very much. But what you do when you make the cabinet very rigid is actually just to push the frequency up and the amplitude down. And that is exactly what you don't want to do because you get the cabinet movement actually intermodulating with the other drive units, the output from the other drive units. That's one of the things, funny enough, which doesn't get measured on loudspeakers — that is intermodulation distortion between the output on different drive units. You often get measurements on the same drive unit but not, for example, you know, say, 50 or 60 Hz or something and 4 or 5 kHz. It's a rather difficult thing to do, because it's extremely noisy because none of the equipment is that sensitive. And the other thing is that it's the sort of thing that you need to sweep, because it's quite difficult to find where those intermodulation things happen. But on most speakers which actually have any sort of dynamic range in any sort of frequency range you'll find there are areas in it, in the output of the speaker, which maybe have 30% or 40% intermodulation distortion.
PS: Huh, now this is intermodulation distortion in what range and what levels?
JV: Well it depends on the speaker. It's very, very difficult to find, but you can hear it as clear as clear, and you can measure it using accelerometers to find out where it's going to happen. But it's very difficult to actually locate it using acoustic methods, so it's one of the areas in which we've worked very hard. And on the DBL we have the midrange unit which is mounted on the baffle but the baffle is actually slotted and filled with a little bit of compliant material so that the mechanical movement of the midrange is not affected by any of the things which happen from the bass bin which, in any event, is on a different part of the stand. It's sort of like a mechanical central earth point down at floor level. And it also doesn't put a large amount of energy into the rest of the baffle to modulate what happens to the tweeter which, in any event, is on its separate decoupled, sort of like a decoupling, plate. And all the frequencies which the drive units are decoupled at are all outside the relevant bands so that as far as they're all coupled to the right parts at the frequencies that they are reproducing, but not so the mechanical energy comes to them at any of the frequencies which cause audible intermodulation or even measurable intermodulation.
PS: I see.
JV: And it's — all our speakers are — designed in that way, and we've been doing it for some years so we have quite a lot of experience. But this is like definitely the top of the range. And the other thing we've done is to make it very, very efficient considering we quote frequency response 17 Hz to 20 kHz with an efficiency of above 92dB.
PS: That makes it about 6dB more efficient than the average loudspeakers ...
JV: At least.
PS: ... it’s the equivalent to an increase in amplifier power of four.
JV: Yeah, but it's actually a bit more than that, because when we say a Watt we actually mean a Watt, not 2.82 volts, and a lot of speakers which have so called high efficiencies with 2.82 volts actually drop to about 2 or 3 ohms, and so that actually you're talking about a lot more power in reality.
PS: I see. And what is the maximum power handling capacity? To put it a different way, how loud can the speaker play?
JV: You can get a peak of about 130dB with ours.
PS: Whew! Well, that's certainly up in the ear damage range.
JV: That's right. It's the only system that I've ever had at home, including PA systems, which actually plays cleanly too loud, to the point where you know you just don't listen to it flat out ever. But it does mean that there is headroom and so at normal average listening levels say 105 to 107dB, it is absolutely clean. Which by the way is extraordinarily loud any way.
PS: Yes, yes, you can't, you could hardly even shout over that.
JV: That's right. But you know for operas particularly, you just don't want to cramp the style of the musicians and performers. And it will peak, you know if you went to a live event and you were reasonably close in you get those sorts of levels on the peak, and it's nice to be able to do that at home.
PS: Yes, now this also opens the possibility I imagine of having speakers like this with a relatively low powered amplifier of some delicacy, which might be a desirable thing for a lot of people. May I ask what the retail price is approximately?
JV: The speakers are, in active form, $15,000 a pair.
PS: Okay, active form. Now we haven't talked about that yet.
JV: Right, well that's with an electronic crossover and you can either have three stereo amplifiers or six mono amplifiers after the electronic crossover, making a tri-amp system or what we call a six-pack.
PS: Right, I see, so bi-amping is not in question here, you either...
JV: No, no.
PS: Okay.
JV: That particular scene I think is fraught with difficulty and is more a marketing ploy by the people who make cable.
PS: Well, you're talking about bi-wiring or...
JV: Yes bi-wiring.
PS: I was talking about bi-amplifying, so it's either all in one or tri in your case.
JV: That's right.
PS: Okay.
JV: Yes, you can have a passive crossover that is due later on this month, which is additional cost, but I don't have a price on the passive crossover. But it's easy to change the speaker one way to the other; the passive crossover just hooks on the back.
PS: That's nice, that's smart.
JV: Again all our speakers, the IBL, the SBL, and the DBL are all made that way, so that you can very easily change them either from passive to active or back again.
PS: We should mention that we're talking with Julian Vereker, the founder and Managing Director of Naim Audio in the UK. Can you say again what the initials of the various loudspeaker models mean?
JV: IBL is Integrated Box Loudspeaker, and SBL is Separate Box Loudspeaker ...
PS: Oh, it's S as in Sam.
JV: ...S as in sugar, and DBL is Decoupled Box Loudspeaker.
PS: Ahuh, okay. Well, since in some ways implicitly, just semantically the integrated box loudspeaker, the IBL, sounds as if it has to have in some sense an opposite design philosophy from the DBL, I'm wondering if you could say something about that.
JV: Right, that's a very small and elegant two-way speaker and it's not designed as a budget speaker at all — it's designed as something to offer the absolute highest quality where you don't have a great deal of space. It's not a wonderful idea on that speaker to economise on the rest of the system. It's literally just to meet people's aesthetic desires. Particularly people's wives' aesthetic desires. And so it's not compromised in that way. It's one box mounted on its own stand but the tweeter is actually decoupled from the rest of the box, by a mechanical filter, and the same technology is used though between the bass midrange unit and the bass loading bin so to speak. But because it's a small box we can make it sufficiently rigid and it doesn't go to that low a frequency, about sort of 40 Hz, 45 Hz is about as low as it will go, but it doesn't have a fundamental resonance so you can actually follow the tunes in the bass line very, very easily. Although you won't get enormous amplitude — i.e., if somebody is into reggae it's probably not the speaker for them. But as far as any other sort of music is concerned you can follow the bass lines really easily and one of the reasons for this is actually a trick of our hearing: you don't need a large amount of the actual fundamental as long as the harmonic structure is properly maintained ...
PS: Right.
JV: ...and of course with a speaker which has a fundamental resonance, it does not, the harmonic structure doesn't remain accurate so it's difficult to find out what tunes the bass is playing. So, yes, you're right in theory about it should be different being integrated but actually it's the same technology and it's a very slim little speaker and very, very elegant.
PS: So these are all currently in the line.
JV: All currently in the line. The IBL and the SBL have won industry awards in the UK, the SBL one year and the IBL the year afterwards, as the best loudspeakers in the UK, in 1988 and '89 ...
PS: Congratulations.
JV: ... thank you ... and have been very, very successful for us. One of the other things which we feel is important about a speaker is that it shouldn't be such that it suits one sort of music more than another. I personally like all sorts of music from baroque through classical and opera all the way through to jazz fusion and of course rock music. And I don't want to have to go into a different room, or change my speakers or anything like that because I want to put a different record on.
PS: Right, of course.
JV: So it's important, we think, that the speaker should have flat frequency responses and should work in peoples' rooms. So they're all designed to actually go against a wall because you can actually control the sound in the room much better from the room boundary in a much more consistent way. And, of course, one of the other questions that raises, people tend to say "Oh yes, but unless the speaker is out in the room you haven't got any depth" the depth actually is something which is a function of the original recording, which may or may not have depth recorded on it. You can artificially get depth by losing the beginnings of all the notes and making the thing a bit fluffy and airy, and you do that easiest by moving the speaker out into the middle of the room.
PS: Hah, that's an interesting viewpoint. Well what about those early reflections of the back wall, though, at mid bass and lower midrange and so on when the plaster wall behind the speaker actually produces a reflection delayed by a few milliseconds and causes some comb filtering and so on: do you recommend that people put some sort of absorptive material around the speakers?
JV: No. One of the most important things appears to be how close you have them to the side wall, and there are a whole lot of rather noticeable comb filter effects if you have them the wrong distance away from the side walls, and that in fact depends on the size of the baffle of the speaker. But we go to some trouble to control the dispersion using the foam fronts which are fairly carefully sculpted on the back to ensure that you don't get the dispersion actually being too wide. But I mean all these things are a bit of a compromise that once you start putting speakers in rooms but that from our experience has given us the best overall effect of sounding the most like music. The distances and everything of course are in the owners manual so that you know where to put your speakers. But in any event one of the important things about Naim, and this applies world-wide, is that we are very, very keen that the dealer should install the equipment and take responsibility for the installation, and if the customer is not in any way happy about it to refund the money for the system.
PS: That's very decent, and rare.
JV: Well it's all part of the thing ... if you hear a system in a store that's obviously been very carefully set up by experts and probably people who have been trained by either Naim personnel or even been to the Naim factory, it should sound pretty good. If you take it all home, how are you going to get to acquire all that experience just from maybe reading the manual? Now my experience is that most customers don't even bother to read the manuals, so it's unlikely you're going to get the system to actually sound anything like as good as it could.
PS: You've been listening to a conversation with Julian Vereker, the Managing Director and founder of Naim Audio Ltd, a British corporation that manufactures amplifiers, pre-amps and a CD player, as we learned about in this programme, and also a variety of loudspeakers.
- - - END - - -
Since this interview took place there have naturally been changes to Naim's product range. The IBL loudspeaker, for instance, is no longer manufactured and only a few pairs are still available.
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Posted - 2003/02/11 : 19:54:39
