• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required. There are many reviews of audio hardware and expert members to help answer your questions. Click here to have your audio equipment measured for free!

Wondom Jab5 4 Channel Double Tda7498E DSP Integrated Amplifier Bi-amp Aptx-HD Fir Crossover

Audiomaniac3

Member
Joined
Nov 8, 2024
Messages
33
Likes
7
Hello everyone,in this video:

I got a four-channel amplifier from Wondom for review on two TDA7498E microcircuits and with a built-in adau1701 dsp module with a maximum sampling frequency of 48000khz 24bit.

The amplifier has many options for connecting and transmitting a signal to it.The board has a line input, Bluetooth 5.0 Aptx-HD, aswell as an i2s input that allows you to transmit a digital signal directly to it.Esp32 wrover module with squeezelite and lms server,can be used for transfering audio over Wi-Fi with i2s protocol.

Thanks to a wide range of capabilities, the board can be used for 4 channels, for 2 channels each amplifier in mono mode, or in 2.1 mode.

There is also an i2s output that allows you to connect another Jab5 amplifier and have an output for 8 channels.
The Sigma studio software allows you to write a project for your needs, specifically in this video, I am writing project for bi-amping with a phase-linear crossover, using room eq wizard and rephase.
The programmer is sold separately, icp(1)(3)(5) will do.

About output power and hissing,according to the datasheet of the TDA7498e microcircuit, the lowest signal distortion is up to 50 watts per channel.

Also, the cooler on the radiator does not work constantly, but turns on periodically as needed for cooling.In Master mode with Bluetooth connected, the hissing is barely audible if you get close to the tweeter, in Slave mode the hissing is a little stronger if you listen closely.

In general, an excellent thing for its money. Link to Tda7498E datasheet: https://www.alldatasheet.com/datasheet-pdf/view/470927/STMICROELECTRONICS/TDA7498E.html

JAB5 amplifier:https://store.sure-electronics.com/product/756
1000021135.jpg
1000021122.jpg
1000020732.jpg
 

Attachments

  • My Project_1.gif
    My Project_1.gif
    3.8 MB · Views: 37
  • Screenshot_20241224_083838_Gallery.jpg
    Screenshot_20241224_083838_Gallery.jpg
    2 MB · Views: 37
So basically I've managed to get most out of adau1701 and adding linear phase crossover for tweeter and bass speaker,thats how step response and frequency response look like.

Also small video of me showing esp32 wrover with squuzelite hooked up to jab5 with i2s audio transfer :
1000021454.jpg
1000021453.jpg
 

Attachments

  • Screenshot_20241225_104216_YouTube.jpg
    Screenshot_20241225_104216_YouTube.jpg
    813.8 KB · Views: 49
  • Screenshot_20241225_104152_YouTube.jpg
    Screenshot_20241225_104152_YouTube.jpg
    1.2 MB · Views: 51
Also little trick how to fix ported speaker phase shift,all you need to know is which frequency your port is tuned to,in my case edifier r1280t port is tuned to 75hertz,now in rephrase all I had to do is add reversed 2nd order allpass filter in rephrase and that's it.
1000021464.png
 
Lifehack with speaker drivers time matching up to 0.01 ms,run 5-10 repeated sweeps 20-20000 in rew for bass speaker only,and then for tweeter only same way,get rid of faulty measurements,now look at step response,now set desired time delay,or in rephase add sufficient amount of taps to achieve right time delay.As you can see my tweeter was delayed from my bass speaker about 0.12ms,now they are perfectly time alligned.

Speaker time alligment with step response:
 

Attachments

  • step1.jpg
    step1.jpg
    521.1 KB · Views: 41
  • step2.jpg
    step2.jpg
    518.4 KB · Views: 41
  • step3.jpg
    step3.jpg
    517 KB · Views: 40
Last edited:
Ofcourse having linearphase crossover with almost perfect time matched speakers is not enough for enjoyable audio experience,final step is to measure speaker frequency response and add linear phase crossover,big advantage of linear phase eq is that it doesn't add ringing and distortion to the signal,only adds small audio delay,in my case it's 125ms,and having option to create as many impulse files for any kind of target curves,without messing speaker phase response is really nice.Even compressed audio over Bluetooth protocol sounds great with adjusted frequency response,so adjusting frequency response is mandatory thing to do, only requirement is equalizer apo with convultion plugin or some media player like Jriver.
 

Attachments

  • z4.jpg
    z4.jpg
    521.7 KB · Views: 49
  • z2.jpg
    z2.jpg
    324 KB · Views: 49
  • z3.png
    z3.png
    102.5 KB · Views: 50
Back
Top Bottom