Please help - Problems with Sony STR DE675 Receiver

cda_kel

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Jan 13, 2011
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Hello!

I'll try to make this short and to the point. We just bought a house that has a built-in 5-channel surround system, but I had no receiver, so I picked one up off Craigslist - a Sony STR-DE675. I'm no home audio expert, but I am reasonably tech-savvy, so I had no problem setting it up.

The speakers are WAY out of balance. The center speaker is by FAR the loudest, followed by the rear right, then front left, then front right, and I don't think I can't ever hear the rear left OR the subwoofer (I tested the subwoofer on another source and it works).

The first thing I tried was to switch the cables around to see if it was the speakers - it's not. Then I downloaded the manual and went through the process of setting up each speaker. I spent hours tweaking and playing with just about everything. I reset it to factory settings. Nothing works. The only reasonable fix is to set it to two channel, and adjust the balance to compensate.

Could there be a short in the wall somewhere? Is it just a bad unit? The guy gave me his word it worked, and he lives just down the road from me, so before I take it back to him I want to make sure there's something I'm not overlooking here.

Thanks in advance for your help.
 
when you are playing media that does not have encoded surround, 2 channel might be the best setting. some surround amps have a mode to use all 5 speakers without the encoded signal. (simulated surround) the mode setting on the amp can be important. Check the speakers one at a time, are the tweeters blown? did you set the volume of front, rear, sub individually???
maybe the amp is screwed up.
Maybe you have access to another amp that can be used to test again?
 

anwaypasible

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the receiver should have seperate volume controls for each speaker.. and those volume controls should make a huge difference (ie turning the speaker up all the way to turning it off).

you said you spent hours in the menu of the receiver.. what exactly was the result with each setting that has something to do with speaker setup/volume?

because you said you tested each speaker individually and came to the conclusion each speaker is okay.. there obviously isnt anything wrong with the speaker wires in the wall.

sony receivers usually have a setting that turns the subwoofer pre-out on and off.
 

cda_kel

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Thanks for the replies. I did individually adjust each channel, but it doesn't seem to have an actual "volume" setting for each channel, it just lets you adjust the "level" (+6 / -6 for each channel). The volumes are SO out of whack with each other it really doesn't make much of a difference when I adjust these levels. Same thing with the balance and fade. I can hear the difference when I make adjustments, but it is so insignificant compared to the disparity between each speaker.

I am thinking it is the amp that is messed up - he probably did something when he was unhooking it like cross speaker wires?

Where could I get another amp to test? I hate to just trash the thing...
 

MozartMarine

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I just purchased a Sony STR-AV970 from a local charity fundraising store. When I first hooked it up it had no front speaker output. As I troubleshot the problem I restored the front speakers but went through several moments of channel imbalance like you are referring to. It is now all balanced and sounds like one would expect it to fresh from the Sony factory.

I am offering this story to you because your problem may be as simple as mine - corroded cable connectors. Not the cables on the exterior of your stereo. The cables that connect the various boards within the unit.

Before you open up your unit and start poking around please be confident you are trained and qualified to be inside the cover. I was trained in avionics by the Marine Corps and know all the hazards (some deadly) that lie within the casing.

Anyway... my problem was the cable that carries the output power from the amp board to the board that "feeds" the front :hello: speaker wire connectors on the rear of the stereo. The connections on the amp board were corroded. I merely removed them and re-plugged them numerous times which removed the corrosion and restored the output signal strength.

Bear in mind that corrosion on these connectors may not even be visible with the naked eye. And it won't be massive brownest-yellow rust because we aren't dealing with iron connectors. It is an extremely subtle white corrosion on silver connector pins and is very difficult to spot.

Good luck and happy listening!
 

anwaypasible

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i've also had good results with time alignment.
there is a difference between the speakers being louder than the other OR if they dont blend well together because the outputs are not being heard at the same time.

i've used time alignment with the THX setup console that comes with my soundcard.
and
i've used time alignment with foobar audio player, thanks to a plugin called 'channel mixer'

of course, this requires the receiver to be connected to a computer.. but there are pieces of hardware that connect between the source (dvd/bluray player) and the receiver.

one example of such a piece of hardware is the audiocontrol 'diva'
http://www.audiocontrol.com/19872/products/Room-Correction-Processor----Diva.html

i have started looking for processors that are better suited for todays surround sound formats, but i havent found anything yet.
if you are willing to try an alternative to your hardware player, a video player with reclock audio renderer is a pretty solid solution.
some people might not be willing to sell their hardware dvd or bluray player.. but for those willing to give it a try, using time alignment is really worth the attempt.

reclock keeps the audio and video in synchronization.
ac3filter decodes the surround sound format, and gives the option to use time delay for each speaker.
i havent looked for another plugin that can be used for time alignment while watching movies on the computer.
my amplifier makes me happy, but the time alignment settings on the receiver are extremely weak (i dont think they work much at all compared to the time delay of the THX setup console or 'channel mixer' in foobar)

i would like to continue using my computer to watch movies, but i will need to decode the new surround sound formats in software mode until new soundcards are released that decode the surround sound.
i'm hoping i can connect a piece of hardware in the chain between the soundcard and the receiver AND keep the audio and video in synchronization.
an additional equalizer with time delay would benefit the final output.
and i find this to be true for any receiver that already has an equalizer (or some auto calibration routine).
it's true, if you ask a single equalizer to boost a frequency too much.. the output can distort.
so if you use more than one equalizer, you can use two to boost and get the amplification you need without the distortion.
the new dolby trueHD and dts-hd surround formats are 24bit with sample rates of 96khz (or 192khz for dts-hd master audio)
that means the 24bit processing inside the audiocontrol 'diva' should be enough.
the only problem is.. you have to output the audio in analog format from the soundcard.
meaning.. the high quality digital to analog convertor inside the receiver wont be used anymore.
you can grab a used receiver that decodes dolby digital and dts to use the amplifier only.
its a solid alternative for those who simply cannot afford the hundreds of extra dollars for todays new high quality equipment.
you shouldnt have to watch movies with low quality audio when this alternative exists.
the rising cost of gasoline should be one reason to need a savings.
but
the high cost of digital cable is another reason to need a savings.
new televisions are expensive, and are another reason to need a savings.
some of the new televisions are failing after the warranty is expired.. and that is another reason to need to save some money.
bluray rentals are more expensive than dvd rentals.. another reason to save some money.
the only downside to this alternative is selecting an amplifier that sounds just as good as the new ones.
there are a lot of amplifiers with 1% total harmonic distortion.

building your own speaker cabinets can also create extra cost.
but
if you have the tools (or buy the tools and find building speaker boxes are easy) you can always put an ad in the local paper to build speaker boxes for other people to make some extra money and provide for your community.
 
Mar 3, 2018
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I know it's been a number of years now but did you ever find a solution. I am having the same issue with the same receiver with exactly the same symptoms.
 
Page 20 of the owners manual has details for setting speaker volume. Go through the entire speaker set up procedure setting the speaker size and distances too.
https://docs.sony.com/release//STRDE675.PDF
The volume of the front and rear speakers should be adjusted to have the same volume at your listening position when the noise plays through each speaker. The subwoofer level is set to taste. You can do this by ear or download a sound level app for your phone.