From ???@0x00000FCE Mon Jun 23 08:48:48 2003 Path: pitt.edu!newsflash.concordia.ca!nntp.cs.ubc.ca!newsfeed.stanford.edu!postnews1.google.com!not-for-mail From: gorcook@charter.net (G. Cook) Newsgroups: rec.audio.tech Subject: Re: BOSE WAVE RADIO... Date: 22 Jun 2003 09:41:59 -0700 Organization: http://groups.google.com/ Lines: 52 Message-ID: <91db11cc.0306220841.6f764235@posting.google.com> References: <54258935.0306141807.2b1e00b0@posting.google.com> NNTP-Posting-Host: 68.116.199.41 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit X-Trace: posting.google.com 1056300119 12303 127.0.0.1 (22 Jun 2003 16:41:59 GMT) X-Complaints-To: groups-abuse@google.com NNTP-Posting-Date: 22 Jun 2003 16:41:59 GMT Xref: pitt.edu rec.audio.tech:183755 Status: N randycat99@earthlink.net (dangling entity) wrote in message news:<54258935.0306141807.2b1e00b0@posting.google.com>... > I wonder, has anyone ever attempted to do frequency response, > distortion, and SPL measurements on one? Is this information posted > anywhere? **Disclaimer: I was the electronics designer of the Cambridge Soundworks Model 88 and the Tivoli Audio Model One by Henry Kloss, and the Tivoli PAL radio. These are my opinions and are not that of Cambridge Soundworks, Tivoli Audio or anyone but me.** I did measure a Bose Wave Radio's frequency response recently, although I would not claim the measurement to be thorough. Using a near-field position about 3" in front of the right speaker and port, I found that there is a peak at about 80 Hz, which I presume to be the effect of the 1/4 wave folded pipe. This peak is apparently augmented in the electronics by variable bass boost, which is volume control level dependent. If the volume is up all the way the peak disappears, and the sound is noticeably different. The 80 Hz peak gives a 'one-note' bass effect, which gives an impression of good bass response. With 2 1/2" drivers, the resonant pipe is probably the only way to get much response below 150 Hz, to be fair. However, despite the elaborate claims, they haven't repealed the laws of physics, so the resonator has to have fairly high "Q" to give an acoustic output comparable to the upper range, so it will be a narrow peak. (The analogy to the flute used in the advertising gives away the obvious flaw in this type of design, since the flute only plays one note at a time.) The near measurement I made also indicated a dip and peak between 200 and 300 Hz, and then another peak between 3-5 KHz. My experience is the 200-300 Hz dip and peak will color voices to be 'dry' or 'thin', and the 3-5 KHz peak will make the sound be very forward, and emphasize harmonics of instruments, drums, etc. Peaks in the response tend to be tiring after a while, IMHO, although these aren't terrible. The peak in the bass is most noticeable, however, on string bass runs, etc, where you expect to hear different notes, but only one comes out. I didn't measure it, but to my ear the distortion is very good. The electronic design of the radio is well implemented, and operated without flaws or obvous glitches. It has a relatively huge AC power transformer in the middle, which I can't quite figure out why it is so big. It doesn't play party loud but it is fine for normal room listening. Again, the balance of the sound changes dramatically as you turn it up. The FM uses an off-the-shelf Japanese RF front end and IF IC. I didn't measure the performance, but it should be similar to mid-priced receivers. The AM worked well. Based on my experience with manufacturing these types of consumer products, I would guess that the manufacturing cost should be about $60 - $65. (This assumes non-US manufacture.) With a 'normal' X4 markup for audio components, the retail price would be $250, with 40% of that going to a dealer. Since there is no dealer involved, all the markup goes to Bose. G. Cook