Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Posting-Version: version B 2.10.1 6/24/83; site opus.UUCP Path: utzoo!watmath!clyde!burl!ulysses!mhuxl!ihnp4!zehntel!hplabs!hao!cires!nbires!opus!rcd From: rcd@opus.UUCP (Dick Dunn) Newsgroups: net.audio Subject: Tubes, CDs, sq waves, nonscience (the bleat goes on) Message-ID: <579@opus.UUCP> Date: Thu, 28-Jun-84 03:16:25 EDT Article-I.D.: opus.579 Posted: Thu Jun 28 03:16:25 1984 Date-Received: Sun, 1-Jul-84 04:23:40 EDT References: <66@sunybcs.UUCP> <65@sunybcs.UUCP> Organization: NBI, Boulder Lines: 84 ONCE AGAIN, we rejoin Charles Pearson. First, we see Pearson battling the awesome foe, Audio Theory: >For all of those out there who insist upon praising CDism and >their (non)square waves by relying on the FFT sine-wave generation >approach have missed something intrinsic in their approach. Charles, Ivor Tiefenbrun (sp?) loves you for writing things like that. (For all I can tell, he could be PAYING you for writing things like that.) I hold no brief for (or against) the CD, but I tend to get a little annoyed when someone who (apparently) knows virtually nothing about signals, frequency response, Fourier analysis, and the like, makes ignorant statements about CDs and square-wave response, and continues making them in the face of massive refutation. Face it, there have been almost 20 articles that I've seen here in the past week or so, from numerous contributors, trying patiently to explain to Pearson that he's in left field. I haven't seen ONE article coming to his defense - small wonder; almost everything he's said has been wrong. I'm all for moving the whole square wave discussion to net.flame. The ratio of technical content to emotion in Pearson's postings ( 0 : a bunch) certainly doesn't merit keeping them here, and the people who have refuted his arguments could well spend their time and patience on matters of greater substance and interest (though I thank them for taking the time to TRY to straighten him out). >This method will produce a 'square' wave with maximal distortion >at the points of the square, not a uniformly decaying sine wave >distortion. In case you're wondering, this is an explanation of how Fourier analysis of a square wave gives the wrong answer. My best surmise is that a sketch of a square wave with a (dull) No. 2 pencil gives the right answer. But I promised more than the square-wave topic... >Since it is almost universally accepted that the sample rate >of CDs is as low as possiple (or even too low already) I >thought that you would like to know that at least one SONY >CP player is playing in multi-plexed mono... cutting the >sample rate in half. I must be getting rusty - I just can't keep up on terminology. First I can't figure out what is meant by "soggy sound". Now I have to admit that I don't know what is meant by "multi-plexed mono"...Does this mean (1) that the upper frequency limit of this alleged CD player is 10 KHz? (2) that it doesn't use the same CDs as other players, since it only has half as many samples? (3) that it's a mono player??? (4) that Pearson, once again, doesn't know what he's talking about? It was actually interesting, reasoning out the term "multiplexed mono". Now I know that "multiplexing" means combining signals into a single composite signal (rough, colloquial interpretation), and that "mono" refers to a single "channel" or signal. Thus "multiplexed mono" means combining one signal into one signal. Damn clever idea, and I bet it doesn't take much circuitry to do it! (I can forgive Pearson's typos if he'll try to introduce some real semantic content for the rest of us. I'd also like a little substantiation of his arguments - e.g., WHICH Sony player, and very briefly, how does it differ from others?) Then there's the defense of tube equipment. Sure, there is good tube equipment, no question. Is it as good as solid state? Well, "consensus" is a risky term to use around audio, but if there is a consensus it favors SS. There are certainly differences in sound, though the ends of the reproduction chain (mikes, cartridges, speakers) tend to overwhelm them. But the idea that you can hear the transistors switching had to be hatched out of pure imagination. You can run either SS or tube amps in class A, A-B, or B. If the design is screwed up, A-B or particularly B can mess up the signal with "switching" transitions. (Tubes DO have capacitance too, you know...) The problem can be fixed for either tubes or SS, to the extent that the only reasons for running class A are along the lines of a cold house or snob appeal. And if we're going to try to compare tubes and SS, let's try to make the comparison technically sound. Lumping bipolar transistors with, say, MOSFETS (of various configurations) is nonsense; their behavior is as different, for reasons fundamental to the design of the circuit, as the behaviors of tubes (shall we say indirectly heated pentodes?) is different from transistors. (Hey, if tubes are such a damn good idea, where are all the bombardment-heated cathodes?) -- Dick Dunn {hao,ucbvax,allegra}!nbires!rcd (303)444-5710 x3086 ...Lately it occurs to me what a long, strange trip it's been.