mohler@druxu.UUCP (MohlerDS) (04/24/85)
Andy, It is very hard to refute someone's claims, if you don't understand what they are saying. The reason Herb and others have spent time explaining BOSE design flaws is as follows. The measurable differences between many CD players are such things as: very small high frequency response differences, very large phase response differences, filter ringing (that is further excited by fast (high frequency) transients), low level high frequency distortion and a few other items. If you take a speaker that even with its equalizer is not flat at high frequencies, has non-linear phase response, has driver energy storage effects that cause lots of ringing, has an order of magnitude more high frequency distortion than monitor quality speakers how can you expect to hear any result of the above measurable differences? The BOSE 901 also has the problems that multiple drivers and mostly reflected sound provides much worse room interaction, severe cancellations within the room and no possibility of any retention of image. Several dynamic and electrostatic speakers show far fewer problems in these areas. These differences are audible to most listeners. One thing you did correctly point out, is that the room will effect any loudspeaker, however some speakers try to minimize the interaction not maximize it like the BOSE. By the way, that is probably part of why Herb mentioned the Stax pro headphones, they are impecable transducers and you only have ear canal interaction rather than room interaction. Now, go re-read Herb Chong's or George Labelle's or my explanation of the design flaws and you might begin to understand that while you were demanding proof, you were getting it and didn't know it. I further suggest that you brush up on your knowledge of experimental practices. Also an electrostatic driver has in the range of 6 milligrams of mass for a 1 foot by 4 foot diaphram and is driven over it's entire area. It also has very good phase response and if properly designed no significant ringing, and if crossed over with another driver for the bass has very low frequency modulation and other distortions. Since you are one of those "prove it types" like Dick Grantges please see my next Article (hopefully 4-24) I plan on giving you enough references to satisfy any reasonable curiosity. I also plan on dealing with Dick's comments! David S. Mohler AT&T Information Systems Laboratories !druxu!mohler
seifert@mako.UUCP (Snoopy) (04/25/85)
In article <1476@druxu.UUCP> mohler@druxu.UUCP (MohlerDS) writes: >Also an electrostatic driver has in the range of 6 milligrams of mass >for a 1 foot by 4 foot diaphram and is driven over it's entire area. It >also has very good phase response and if properly designed no significant >ringing, and if crossed over with another driver for the bass has very >low frequency modulation and other distortions. A driver 1 foot by 4 feet is going to beam like crazy at hi freqs. This *may* be what you want, but you should be aware of it, as there is going to be a very small listening area. _____ |___| the Bavarian Beagle _|___|_ Snoopy \_____/ tektronix!mako!seifert \___/
herbie@watdcsu.UUCP (Herb Chong [DCS]) (04/28/85)
In article <731@mako.UUCP> seifert@mako.UUCP (Snoopy) writes: >In article <1476@druxu.UUCP> mohler@druxu.UUCP (MohlerDS) writes: > >>Also an electrostatic driver has in the range of 6 milligrams of mass >>for a 1 foot by 4 foot diaphram and is driven over it's entire area. It >>also has very good phase response and if properly designed no significant >>ringing, and if crossed over with another driver for the bass has very >>low frequency modulation and other distortions. > >A driver 1 foot by 4 feet is going to beam like crazy at hi freqs. > >This *may* be what you want, but you should be aware of it, as there >is going to be a very small listening area. > if you sum the wavefronts from the 8 rear drivers already in a 901, you get a similar one to a bent 1x4 panel. it's reflecting off the walls that gets around this problem. Herb Chong... I'm user-friendly -- I don't byte, I nybble.... UUCP: {decvax|utzoo|ihnp4|allegra|clyde}!watmath!water!watdcsu!herbie CSNET: herbie%watdcsu@waterloo.csnet ARPA: herbie%watdcsu%waterloo.csnet@csnet-relay.arpa NETNORTH, BITNET, EARN: herbie@watdcs, herbie@watdcsu