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- Path: sparky!uunet!elroy.jpl.nasa.gov!hanauma.jpl.nasa.gov!hyc
- From: hyc@hanauma.jpl.nasa.gov (Howard Chu)
- Newsgroups: rec.audio
- Subject: Sony STR-AV xx70 (was Re: AV Receiver Recommendations)
- Date: 22 Jan 1993 11:11:52 GMT
- Organization: SAR Systems Development & Processing, JPL
- Lines: 75
- Message-ID: <1jokpoINNgjo@elroy.jpl.nasa.gov>
- References: <1993Jan13.160024.4482@voodoo.ca.boeing.com> <1j5kkjINN9qt@usenet.INS.CWRU.Edu> <1993Jan15.225421.22283@macc.wisc.edu>
- NNTP-Posting-Host: hanauma.jpl.nasa.gov
-
- In article <1993Jan15.225421.22283@macc.wisc.edu> Peter Burke <pburke@macc.wisc.edu> writes:
- >>>> I am interested in the comments/view of the netdom
- >regarding the likes and
- >>>> dislikes of the following equipment. These models are
- >the ones I have
- >>>> been considering, but I am open to new ideas.
-
- >>>> Yamaha RX-V1050, 850
- >>>> Denon AVR1010?, 810?
- >>>> Sony ES STR GX99, 69
- >>>> Sony STR AV2090, 1090
-
- >Well, all I have to say about this list is: stay away from
- >the Sony 1090 - I have a 1070, which is about the worst
- >piece of electronic junk ever sold in this country. I ahve
- >a list of about 20 major problems (and I mean MAJOR -
- >like? it turns itself on when i am not home, and happens
- >to crank the motorized volume to max on its own. Aren't
- >those nice relays and computer chips fun?). No clue what
- >product is actually reliable and good, all i know is that
- >if I can get my dealer to finally exchange the unit for a
- >different brand, I'll be a lot happier than now.
- >
- >The Sony ES series is supposed to be a lot more reliable,
- >but doesn't have any of the fund gadgets the STR-AV series
- >offers.
-
- I'd like to add a bit to this statement. I just took my 1070 back to the
- local Sony Service Center this week, for the same problems mentioned above.
- This is the second trip so far. The only good news is that the unit is
- still in its original 2 year warranty.
-
- I bought the service manual for the 1070, and one can immediately see at
- least one source of problems - as most 1070 owners have probably already
- noticed, the volume knob's motor generates noise on the spectrum analyzer
- display. This is because there is only a single power supply driving both
- the motor and the display electronics, *and* the CPU and all other associated
- circuitry. There are some pretty decent transformers inside for the main
- audio amp, but everything else runs off some puny little IC transformers.
- In My Humble Opinion, the 1070 design is utter crap, and there's no way
- that the model could ever perform without serious electrical problems.
- There just isn't any isolation from the volume motor to any of the rest of
- the control electronics. I'd guess that microprocessor itself is getting
- a good burst of noise on its power as well. I don't have an oscilloscope
- for monitoring, but even with a simple little voltmeter I was able to
- observe non-trivial power fluctuations even when I wasn't making any
- adjustments, using the remote, etc.
-
- I would suggest that any/all current 1070 owners write a letter to the
- Sony Customer Service department and complain loudly and bitterly about
- this unit. (Assuming that you actually *are* encountering any troubles
- with your unit. As far as I know, all the units in this series have the
- obnoxious hiss in the surround channel, and looking at the schematics,
- I can't imagine any unit not suffering from the same electrical problems
- that I and so many others have already talked about.)
-
- I wonder if we can force Sony to issue a recall and get 'em to replace
- all of these things with something from the current xx90 series. It seems
- that the 1090 doesn't have the hissing surround channel, at least. (At this
- point though, I would not buy any new Sony audio equipment. At least my
- XBR TV still works without trouble...)
-
- It's possible that the ES series of receivers has a more intelligent
- design, with independent power supplies for the microprocessor and associated
- control circuitry, but I don't think anyone should *have* to pay a premium
- just to get a workable design.
-
- A lot of folks buy Sony stuff based on their name alone; I think Sony
- deserves to feel a little heat over this issue. The xx70 series only sold
- for just under a year before the xx90 series was released, so it seems to
- me that the Sony engineers knew about the xx70 problems pretty early on.
- --
- -- Howard Chu @ Jet Propulsion Laboratory, Pasadena, CA
-
- There's a rough border between genius and insanity, but I'm a dual citizen.
-