Noise issue from bluetooth source or TDA7498, Help me find. - diyAudio
Go Back   Home > Forums > Amplifiers > Class D
Home Forums Rules Articles diyAudio Store Gallery Wiki Blogs Register Donations FAQ Calendar Search Today's Posts Mark Forums Read

Class D Switching Power Amplifiers and Power D/A conversion

Please consider donating to help us continue to serve you.

Ads on/off / Custom Title / More PMs / More album space / Advanced printing & mass image saving
Reply
 
Thread Tools Search this Thread
Old 15th January 2017, 09:38 AM   #1
diyAudio Member
 
Join Date: Dec 2016
Default Noise issue from bluetooth source or TDA7498, Help me find.

Hi,

I connected 2 amps (TPA3116 for speakers and TDA7498 for sub-woofer) to one bluetooth receiver headphone out, which is creating the continuous hissing noise along with a mild whistle noise throughout. If I disconnect the TDA7498, the noise totally goes away, OR if I disconnect the bluetooth module and connect to my phone out, the noise goes away. I tried to make a common ground, which did not worked well Or may be I did not do it correctly.

both TPA3116 and TDA7498 is connected to 24V power from battery.
for the Bluetooth module, I am using a step down converter to 12V. I also tried connecting the bluetooth to a direct 12V battery terminals without stepdown just to make sure the noise is not from the stepdown converter, but that did not worked, I still have the hissing noise.

So this combination produces Noise
Bluetooth Out + TPA3116 + Sub-Woofer TDA7498 = Noise

and in this combination, there is no noise
Phone Out + TPA3116 + Sub-Woofer TDA7498 = No Noise
Bluetooth Out + TPA3116 = No Noise

Can you please help me find if the issue is with the TDA7498 or Bluetooth module? or something else?

thanks!

P.S,
Amp stereo input cables are soldered to the bluetooth headphone output cable.

Click the image to open in full size.
  Reply With Quote
Old 15th January 2017, 11:03 AM   #2
diyAudio Member
 
Join Date: Jan 2017
Location: Spain
Maybe you should check ground connections, they can generate a lot of noise.
You can add a ground loop isolator or something, wish i can help more
  Reply With Quote
Old 19th January 2017, 03:16 AM   #3
diyAudio Member
 
Join Date: Oct 2014
which BT module are you used?
besides Ground connection,the BT module will be the source of niose
diff output with Cap coupling?any filter on the signal line?
  Reply With Quote
Old 31st January 2017, 12:00 PM   #4
diyAudio Member
 
Join Date: Dec 2016
thanks for the response guys!,
yes, noise was coming from the bluetooth, I was using this bluetooth module, Bluetooth 4.0 PAM8610 taking the headphone out from that board, that caused the noise, now replaced with Bluetooth module output op amp with NE5532 and works good, the noise is gone,

thankyou!
  Reply With Quote

Reply


Hide this!Advertise here!
Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Noise from bluetooth receiver module. Showly Chip Amps 3 18th April 2017 09:08 AM
Amp suggestions for no noise and Bluetooth? nbriles2000 Class D 3 1st February 2017 10:18 PM
USB powering bluetooth = noise. Mortenhoe Power Supplies 3 20th September 2016 09:34 AM
Multiroom audio from bluetooth source - is it possible? Razva Everything Else 8 5th June 2015 01:02 AM
bluetooth boombox noise problems... help! torclausen Class D 18 3rd October 2013 02:36 AM


New To Site? Need Help?

All times are GMT. The time now is 04:47 AM.


vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2017 DragonByte Technologies Ltd.
Copyright 1999-2017 diyAudio

Content Relevant URLs by vBSEO 3.3.2
Wiki