TPA3116D2 Amp

Jump to Latest
#9,987
Hi all,

I'm building dual mono PBTL with the DUG-1 board (schematic attached). I'd like to correct set the master/slave configuration, so just wanted to check some parameters:

1) With 26db gain, the master board will have an R4/R5 (gain setting pair) of 100k/20k.
2) The slave board will have 75k/47k.

Does that check out?

Next, some more questions:

So the schematic incorrect lists R7 (SYNC pin resistor) as 47k - as this was incorrectly listed on the EVM schematic in revision C - and should be 4.7k as was corrected in revision D. C5, the other component relevant to master/slave clock sync is 47pF.

1) Should I populate R7 (with 4.7k) and C5 (with 47pF) on both the master and slave boards?
2) Would it be beneficial to twist the SYNC wire around a GND wire? The DUG PCB exposes both in J5, so this would be very easy. The boards already have a shared GND.

Thanks for all the help!
 

Attachments

#9,990
Scarface1 said:
My subwoofer is 4 ohm and my satelite 8 ohm.
I also have a maxamp20 amplifier that have 11.5 watt RMS with 12 volt and it goes 3 to 4 times harder than my tpa3116d2 2.1( with bluetooth is goes twice the volume).

I think i are really close with this measurement. It defenitily not goes loud.
Click to expand...

What's the gain of the chip on the board. You can have a 24v PS with 4 ohm speakers. If you not putting in a high enough signal vis-s-vis the chips gain setting, you won;t get the power out. See my paper on this.

View attachment Amplifier Power Out.pdf
 
#9,991
Amp Schematic.jpg
 
#9,992
millstonemike said:
View attachment 598710
Click to expand...

C1 high pass frequency will be affected by the position of the input pot.

When your sub volume is at the top the two opamp buffer outputs are connected to each other.

I do not think this is a good idea.

Your low pass filter should be fed from a low impedance source, not a variable impedance source pot (VR2). This will change the filter characteristics.

Assuming you are using split supplies the DC Signal Bias Resistor should probably be 0R0 IMHO.

Here is the method I used for my 2.1 boombox:
 

Attachments

  • BOOMBOX.JPG
    BOOMBOX.JPG
    44.9 KB · Views: 1,738
#9,993
DUG said:
C1 high pass frequency will be affected by the position of the input pot.

When your sub volume is at the top the two opamp buffer outputs are connected to each other.

I do not think this is a good idea.

Your low pass filter should be fed from a low impedance source, not a variable impedance source pot (VR2). This will change the filter characteristics.

Assuming you are using split supplies the DC Signal Bias Resistor should probably be 0R0 IMHO.

Here is the method I used for my 2.1 boombox:
Click to expand...

Not my design, a reverse engineering of a popular 2.1 board from China. Yes, I had noted that when the sub pot is at maximum, the L-R op-amp outputs go from a passive summation to shorted. So I know not to turn the pot all the way up (and to use the L-R volume to balance).

It is a single supply board.

Agreed on the variable pot analysis but in practice, these audio taper pots (typically "B" if not "A" taper) are typically set at a fairly low impedance as the user is trying to extract maximum gain from weak phone outputs with the chip set at only 26 dB gain.
 
#9,995
millstonemike said:
What's the gain of the chip on the board. You can have a 24v PS with 4 ohm speakers. If you not putting in a high enough signal vis-s-vis the chips gain setting, you won;t get the power out. See my paper on this.

View attachment 598660
Click to expand...

I read it but don't fully understand. So i have to put the gain up. What is that gain? With bleutooth it go harder because of the higher input signal, but is this the same as gain or do i have the look somewere else on the board?
 
#9,996
This was in answer to my query whether I could use a 3116 2.1 amp to power up a bucket sub (post #9808):

Poultrygeist said:
Ed, their inventor says 300 watts and his will rattle the windows next door.

I use a 300 watt plate amp but I think you could get by with less.
Click to expand...

I've since built the bucket sub and am delighted with the results. I have a fairly small listening area and typically listen at fairly low levels. The bucket sub has really filled in the bottom end, almost like a giant loudness switch, but with detail and plenty of punch if I wind it up a bit.

Considering the entire system is comprised only of a 24V 6A SMPS. a Sanwu 2.1 amplifier, a pair of JVC midi system speakers and the bucket sub, I'm well satisfied with the results, and the cost.

My remaining issue is with the pop that is generated on switch off, it's particularly loud in the sub, even with the volume pots turned down prior to switch off. Can one of the boffs on here help me to install a mute switch to overcome this? The amp I'm using is this one:

http://www.ebay.com/itm/121824376824?afsrc=1&rmvSB=true
 
Last edited:
#9,998
You must log in or register to reply here.
Top Bottom