TPA3118 60W Power Amp Module

I prefer the safe way. But I see several TPA3118 building with no big wattage resistor.

temol said:
Before connecting the module to the speaker I'd user 100W 8R resistor as a load and measure output power (with oscilloscope).
Click to expand...

This big resistor is just to use this amp with oscilloscope or I need it if I use the amp with a speaker to play the guitar?

I found these:
- 6.8 Ohm http://www.banzaimusic.com/6-8-ohm-100w-wirewound.html
- 10 Ohm http://www.banzaimusic.com/10-ohm-100w-wirewound.html

Thank you, I'll take a look to the link, trying to understand what it is.

I really don't know when, but once I built this power amp properly (I still don't know the form: pedal, just power amp, mini head with some preamp, easy, complex...) I'll use a good speaker. I could to buy a cheap, but good, 12" guitar cabinet (my 8" is a cheap guitar speaker in a wood box!). Or, initially, and if I can use it safely, I could to connect this amp to one or both speakers on my 120w Crate amp.
Then I need even a good PSU, I guess. The RockPower 18v 2000mA I mentioned before... Do you think it's ok? I never used it, just because I noticed that was a bit noisier then my old red label Boss PSU.
For this amp I thought to buy an used laptop PSU, if I'm lucky it will be cheap and, most important thing, noiseless.
 
Big resistor is a dummy load, only for testing/measuring purposes. You're going to use 60W module with 15W speaker. So in my opinion it's good to know how far you can push it before you damage the speaker. 2A PSU seems to be enough, especially that you're not going to push it to the max. But you'll see everything when testing. Just measure current draw.

Ebay listings for 8R, 100W resistor.
 
Hey All,

First post loving the thread.

Question?

I'm using a 50k pot as my volume control... and even all the way up its really quite.

When i remove the volume pot and connect it direct to a pedal..... wow... this thing is so loud.

I tried a 10k pot and didn't get any sound... amy ideas?

Cheers Baz
 
Bazmatron said:
Hey All,

First post loving the thread.

Question?

I'm using a 50k pot as my volume control... and even all the way up its really quite.

When i remove the volume pot and connect it direct to a pedal..... wow... this thing is so loud.

I tried a 10k pot and didn't get any sound... amy ideas?

Cheers Baz
Click to expand...
These amps take line level (about 2V peak to peak) for full volume. Guitars and pedals are instrument level (about 200mV peak to peak). You must use some sort of preamp that will get up to line level. I've posted multiple solutions in this thread.

Edit: Oops, I misread your question. You have the pot connected wrong... Draw up what you have done and post some pictures.
 
Cheers for the reply.

I just followed the diagram with the 50k pot aand cap on page 2 or 3. Was very strange.

Not sure if there was an issue with amp module so im checking that out now.

Is there any reason it would be low with the pot connected?

From what I've read people use a dual buffer with a volume control so going to try that
 
You need a buffer in front of these boards somewhere along the line, I put one before and after the volume pot. You'll get a great result using a buffered pedal, but no so much if you plug straight into it.
 
Really looking forward to seeing some projects with this board. I bought some fake TPA3118 (28 pins instead of 32 pins) from Aliexpress. They work surprisingly well, but I would love to have a legit source, so looking forward to its availability from PedalPCB.

Has anyone heard when they will have them back in stock? I'll be order a few to replace my fake ones as soon as they are available.

BTW, for those who don't have the isolated Neutrik jacks, I had success using those isolation washers (with the sleeve) with regular mono jacks. I just had to drill it to 7/16" (instead of the usual 3/8") to fit the isolation washer from the inner side. I also used a regular nylon washer on outer side, but can confirm that isolates the jack just fine.
 
After I read your post I checked my TPA3118 PCB I bought from ebay. It's still close in the bag because I didn't try it. It has 28 pin, so it's a fake!
What's the difference? It will work good as the genuine one? Max voltage, watt, noise, distortion...

In an electronic forum I found this:

Guy 1: Any idea what these chips actually are? It's a 28-pin SSOP package, and can handle a 21V rail just fine. They sound terrible but I guess that's expected for a fake, remarked chip. These are sold on Amazon (India) for just under $5 each. Interestingly the listing shows the correct PCBs, but this what you get in the package.
I want to reduce gain and/or try PFFB to improve things, as someone who's using a remarked $2 chip will be using inductors below the bottom of the barrell. I soldered the headers and thus can't legitimately ask for a return, but I wasn't expecting fakes so I didn't pay much attention.

Guy 2: Those are TPA3110 chips (or some Asian equivalent).
I had the same issues. Check couple of page back in this topic.
There is a little error in the board, just connect pin 5 and 6 to ground and your board will be nice and quiet! :)
(ground should be on pin 3 and 4 if I am not mistaken, but pls double check)
 
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Elijah-Baley said:
After I read your post I checked my TPA3118 PCB I bought from ebay. It's still close in the bag because I didn't try it. It has 28 pin, so it's a fake!
What's the difference? It will work good as the genuine one? Max voltage, watt, noise, distortion...
Click to expand...

Funny, last night, I was actually just reading the same comments on the electronics forum you quoted from!

So I boxed one of these fake ones up a couple days ago:
  • I do believe these are lower wattage/output. Based on what I read about the genuine chips, I expected this to be louder.
  • There is some hissing if I attempt to use a volume pot to lower the volume using the wiring diagram that has been floating around (on the TheGearPage). No buffer, but simply a 50k log pot going into the input (with a 220nF cap in series), and the other wiper going to ground. I am sure I did the wiring correctly. The hissing problem goes away if I dime the volume knob and control the volume with my preamp pedal. I'm guessing that a genuine chip wouldn't have this problem due to the number of people happy with the results with that wiring diagram.
  • Overall, if I use it with volume knob dimed and control the volume from the preamp, it sounds really good. Lower volume than I expected, but it is clean headroom for driving a cabinet for home practice and light rehearsals.
  • I looked at pins 5 and 6 after reading that post and it doesn't appear to be floating on mine and it wasn't obvious that I should be connecting them to ground. I honestly don't trust the smallest soldering tip I have to be able to solder anything to those pins without damaging the chip, so I will likely just leave it alone.
I'll be replacing it with a genuine board as soon as I find a source, or whenever PedalPCB gets them in stock!
 
tcpoint said:
What power jacks are you using? The power supply I have is rated at 24 volts and 3 amps.
Click to expand...
2.5mm center-pin. Center positive. Can be isolated or not... I've used these:

Of course, make sure your power supply is center positive, too... And I strongly recommend a 1N5408 in series with the 24V in case your power supply overshoots. Even a little can blow the caps.
 
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I thought I saw a comment from Chuck Bones many moons ago re: a level of caution using any ol' computer laptop PSU for these. Is this simply a matter of having plenty of current to deliver that extra umph when needed? Are there any guidelines we can look to in purchasing an adequate PSU? How about one of the Mean Well PSU's Parts Express sells for powering Class D boards? They're not that expensive for a 5A PSU?
 
Mike McLane said:
I thought I saw a comment from Chuck Bones many moons ago re: a level of caution using any ol' computer laptop PSU for these. Is this simply a matter of having plenty of current to deliver that extra umph when needed? Are there any guidelines we can look to in purchasing an adequate PSU? How about one of the Mean Well PSU's Parts Express sells for powering Class D boards? They're not that expensive for a 5A PSU?
Click to expand...
I’ve used actual laptop power supplies and inexpensive generic laptop “style” power supplies from Amazon with no issues at all. Just have to make sure the polarity and size of the plug is correct. I sometimes just cut off the plug and solder the proper on on. And then I use a label maker to stick on a label describing the new polarity so that I don’t have to guess or measure.
 
Mike McLane said:
I thought I saw a comment from Chuck Bones many moons ago re: a level of caution using any ol' computer laptop PSU for these. Is this simply a matter of having plenty of current to deliver that extra umph when needed? Are there any guidelines we can look to in purchasing an adequate PSU? How about one of the Mean Well PSU's Parts Express sells for powering Class D boards? They're not that expensive for a 5A PSU?
Click to expand...
The most concerning thing is the 25V caps on the amp. A cheapo supply might overshoot or not be fully stable at 24V. I've had good results from several different cheap 24V supplies from amazon but I include a 1n5408 diode in series with the supply voltage inside the amps I've built. None have been a problem. The only issue I've had is to use an ungrounded power supply (two prong, not 3-prong). The grounded ones form a ground loop with my pedal board and hummmmmmm.
 
I just received this a few days ago. It comes unassembled so you don't have to use the faceplates unless you want, but it has bluetooth in. Tried it, pretty loud. Not sure what I'm going to do with it yet but I was thinking along the lines of a stereo chorus amp powered with a bunch of 18650's. One 5s sled would yield around 20vdc 2.2AH. Wire a few more in parallel for days of busking without a charge.... :)


1669071257716.png


(edited: here's the watts/input power/ohms data for this. I have some 100w 4ohm celestions I can pop in....)


1669072239401.png
 
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Hopefully the caps are a bit better at handling 24v. The ones on the little 60w modules *say* 35v iirc, but will blow at 24.
I doubt these are 100w. I've been running mine at 19v, its ok. Might try one of these out, as I have a couple of higher power laptop supplies to try.
 
Willybomb said:
Hopefully the caps are a bit better at handling 24v. The ones on the little 60w modules *say* 35v iirc, but will blow at 24.
I doubt these are 100w. I've been running mine at 19v, its ok. Might try one of these out, as I have a couple of higher power laptop supplies to try.
Click to expand...
The 100W amps have 35V caps that I've seen. The 60W amps that I have are all 25V caps:
1669088158683.png
 
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