Question about Onkyo TX-DS939 Receiver

2 Answers

I have an DS-TX939. When you turn the volume nob you get a loud thimping sound from the speakers but no music. You can also here this when using headphones or the Pre outs so there must be a problem in the preamp section I'm assumming. Any Ideas.

Posted by on

  • 5 more comments 
  • davesahim Aug 28, 2010

    Should I replace the capacitors on the Preamp? The power amp section seems to be fine as I can send audio to is directly via the pre inputs. Remeber I get this thumping sound on the pre out and headphones as well. Can bad capacitors on the main amp section create a problem for the preamp? Whe I rotate the digital volume control it make the thumping sound in the same positions every time.

  • davesahim Aug 28, 2010

    There is no audio passing through the pre-amp also from the selected source.

  • davesahim Aug 28, 2010

    I have a copy of the service manual in PDF if that helps but don't know how to post it or send it to you.

  • davesahim Aug 28, 2010

    Should I replace the capacitors on the Preamp? The power amp section seems to be fine as I can send audio to is directly via the pre inputs. Remeber I get this thumping sound on the pre out and headphones as well. Can bad capacitors on the main amp section create a problem for the preamp? Whe I rotate the digital volume control it make the thumping sound in the same positions every time. There is no audio passing from the selected source through the Pre-amp

  • davesahim Aug 28, 2010

    Should I replace the capacitors on the Preamp? The power amp section seems to be fine as I can send audio to is directly via the pre inputs. Remeber I get this thumping sound on the pre out and headphones as well. Can bad capacitors on the main amp section create a problem for the preamp? Whe I rotate the digital volume control it make the thumping sound in the same positions every time. There is no audio passing from the selected source through the Pre-amp

  • davesahim Aug 28, 2010

    After removing about 60 screws on the back panel I was able to get the pc board with the pre-amp. There are about 70 small electrolitic capacitors on this board. Should I start with the capacitors on the output side of the transistors? I have downloaded the service manual with the scematic of this board to help guid me as to what is what. Also, I would think if there was a bad capacitor it would only affect one channel as the cicuits seem to be somewhat descret. Thoughts?

  • davesahim Aug 28, 2010

    I don't think ti is the potentiomenter as when it is rotated the digital display cleanly increses the display in DB.
    I know the power amp is fine as I can send audio into the pre in and everything sounds great.
    I tried many inputs and get the same result.
    I can go with a power problem though to the Pre-amp as that seems to be somthing comen to all channels as they are all having the same problem. Any more thoughts?

×

Ad

2 Answers

  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    Superstar:

    An expert that got 20 achievements.

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

  • Onkyo Master
  • 17,129 Answers

This can be confirmed only by hearing if the outputs are working well. You can open the set and check to see if there is test tone( with a audio signal test) from the input of the power amplifier.
If so we can confirm that the power amplifier is working.
Now the noise in this case can be the potentiometer rubbing with dirt. If so use to vigourously to the left and right to clean out bu itself.
Now tthe possible fault can be failure of power to the preamp section, the failure of preamp or the failrue of the mode selector.
In all the above cases you will need to check with the audio injector to confirm the point of fault.
Try to trigger the selector mode many times, check if any other input is working than the connected one to confirm.

Posted on Aug 28, 2010

  • 2 more comments 
  • Donald DCruz
    Donald DCruz Aug 28, 2010

    Now that your Main amp is working fine, a poor capacitor( short) can make the input cross over, but I think in this case it can be the preamp IC. or can be any of the logic circuits failure...

  • davesahim Aug 28, 2010

    I was originally leaning in this direction as the volume appears to be microprocesor controlled. Not sure if this will be to advanced for me to attempt to fix. would you care to see the Scematics I downlowded?

  • davesahim Aug 28, 2010

    New discovery. The board the the front and rear channel preamps are on are on a diferent board that the one for the Center and sub. The center has the same problem son there must be somthing comen here that is creating this problem before the audio hits the Preamps.

  • Donald DCruz
    Donald DCruz Aug 28, 2010

    COULD BE RELATIVE TO THE MULTIFUNCTION IC. it can be the one with preamp,equaliser,and the audio seperator. Normally the boards are swapped to confirm as working will be difficult to probe unless we have an external jig & harness.

    Good try you are coming to the point.

×

Ad
  • Level 3:

    An expert who has achieved level 3 by getting 1000 points

    All-Star:

    An expert that got 10 achievements.

    MVP:

    An expert that got 5 achievements.

    Vice President:

    An expert whose answer got voted for 100 times.

  • Master
  • 944 Answers

What you are getting is excessive phase shift at the lower-frequency edge of the audio pass band, causing oscillation. This is almost always due to aging capacitors or preamp
.Replacing preamp or capacitors will surely solve the problem.
Hi,

check the coupling capacitors for the speaker outputs. It probably has quasi-complimentary transistor configuration in the amp section. If they loose capacitance the circuit can become unstable.

check the leads on the square transistors.If they are bolted down the leads sometimes break where they are bent.

post a comment for further assistance.


thank you for using fixya have a nice day:-)

Posted on Aug 28, 2010

  • Natarajan Ramasamy
    Natarajan Ramasamy Aug 28, 2010

    Yes you should replace the capacitors on the preamp section.That's the reason why it's causing this sound.This is a common problem it occurs in all receivers.Woofers too have this type of problem.

×

Ad

1 Suggested Answer

6ya6ya
  • 2 Answers

SOURCE: I have freestanding Series 8 dishwasher. Lately during the filling cycle water hammer is occurring. How can this be resolved

Hi,
a 6ya expert can help you resolve that issue over the phone in a minute or two.
best thing about this new service is that you are never placed on hold and get to talk to real repairmen in the US.
the service is completely free and covers almost anything you can think of (from cars to computers, handyman, and even drones).
click here to download the app (for users in the US for now) and get all the help you need.
goodluck!

Posted on Jan 02, 2017

Add Your Answer

Uploading: 0%

my-video-file.mp4

Complete. Click "Add" to insert your video. Add

×

Loading...
Loading...

Related Questions:

1 Answer

My speakers crackle when volume on loud


It's possible that the speaker could damaged or you may have a shortage

May 11, 2012 | HP w17e Monitor

1 Answer

Hello! I'm having problems during a phone call with my speaker volume being too low unless speaker phone is on. All other sounds are loud & clear. I've tried resetting & turning the phone...


Did you happen to update to iOS 5? Because since the update. Mine has been the same way. The volume is very low. and sometimes even the speaker isn't too loud either unless I'm playing music.

If you did not update to iOS 5. Then your speaker might be blocked and easily cleaned with a cotton swab, or the speaker is just old and going out.

Jul 25, 2011 | Apple iPhone 3GS Black (16 GB)

1 Answer

Can i connect my I-TRIGUE 2200 speakers to my laptop? if so, can you tell me how to? I need to amplify my music for a party and I want to use the ones from my brother's desktop and I rather not upload...


Hello,

Plug the speakers in to the head phone jack on the lap top but keep top volume on the laptop FAIRLY LOW. Then play some music and adjust the volume on the speakers.

It it is still not loud enough turn the volume on the laptop UP A LITTLE.

If you turn the volume up on the laptop too much the sound will distort.

Hope that helps.

Jul 23, 2011 | Creative Labs I-TRIGUE 2200 Computer...

2 Answers

Griffin Amplifi 2.1 sound system. The sound coming out of the unit is VERY quiet and does not seem to increase when you turn up the volume with the nob or with the remote.


Hi,


I like to fix things as pet projects...speakers are uncharted territory for me, but my cousin has that speaker and it rocks! You can't find it anywhere...

How's $25 and I'll pay for shipping ?


Thanks for considering (fingers crossed)


Danny

dannymack2.0@gmail.com

Apr 29, 2011 | Griffin Technology Amplifi Speaker System...

1 Answer

Hi the sound for the music player is not very loud unless you put the ear phones in ?


Hi, I have two reasons in mind why this might be;
1: The media volume on the phone may not be turned up all the way, check the Media volume and not just the ringer volume.
2: The speakers on the phone itself may not be designed to be very loud when it comes to playing music, the varying frequency ranges are difficult to pump out at loud volumes with such small speakers. Developers of the phone may have just anticipated users of the music player would always listen with headphones.
If you want a phone to play loudly without having headphones in, specify such a desire to a sales rep in a store so they can suggest the phone that meets the needs that are most important to you.
Good Luck hope this helps

Mar 11, 2011 | Samsung Galaxy S GTI9000 Smartphone

1 Answer

Baldwin Model 230 DE when turned on makes a loud thunk like the volume is turned way up, then when you disturb or shake the organ or stomp on the floor it makes a loud noise like if you twanged a coil...


If the organ has a reverb spring "tank" in it, that is likely where the spring sound comes from.

The initial noise is likely due to the initial unbalance of the power audio amp.

Lesser organs don't disconnect the speakers till the amps attain balance so the inrush pulses the speakers..

Mar 10, 2010 | Michael Kelly Music

2 Answers

There is a loud hum when volume is on low to high


go to control panel
sound and audio devices
voice
under voice recording clk volume and mute the mic phone...........
or
some how your mic is conflicting with speakers. Keep your mic away from your speakers..

Do reply if this woks

Oct 03, 2009 | Bose Companion II Computer Speakers

1 Answer

MY MUSIC DONT GET LOUD AND THERE IS A LOUD STATIC COMIN FROM MY SPEAKERS AND MY VOLUME IS TURNED ALL THE WAY UP


Hey there, you have a sound level on your computer, available in the control panel as well as the volume knob on the speakers. Check the sound level on your pc. Let me know if this doesn't help.
seth

Jun 26, 2009 | E-Machines eMachines Desktop PC

2 Answers

Speaker volume too loud


Have you tryed to turn down the sound volume on the media player its self as well as the the main volume?

Jun 21, 2009 | Dell 5650 Computer Speakers

1 Answer

HOW DO YOU CONTROL THE VOLUME ON THIS DARN THING...WHEN I PUT MY HEAD PHONES ON...THE MUSIC IS SO LOUD IT HURTS!!!!!


hold the volume button untill the speaker immage @ the top highlights red then use the << and >> pads to turn it up or down

Jul 22, 2008 | Kaser Corporation Mambo Mano Digital Media...

Not finding what you are looking for?
Onkyo TX-DS939 Receiver Logo

Related Topics:

75 people viewed this question

Ask a Question

Usually answered in minutes!

Top Onkyo Audio Players & Recorders Experts

 Grubhead
Grubhead

Level 3 Expert

5126 Answers

The Knight
The Knight

Level 3 Expert

74251 Answers

Electro Med Services...
Electro Med Services...

Level 3 Expert

6694 Answers

Are you an Onkyo Audio Player and Recorder Expert? Answer questions, earn points and help others

Answer questions

Manuals & User Guides

Loading...