SuperReverbMan
New member
I bought two of the TPA3118 modules anticipating the next phase of this project. Patiently waiting... 
TPA3118 60W Power Amp Module
- Thread starter falzhobel
- Start date
Vildhjuggah
Member
Whenever this interface board comes out maybe using this case (painted or something) and a friedman be-od deluxe board or maybe a bigger one to make a little amp head 
YaeCCC Rectangle Project Enclosure Case Electric Junction Box Blue 170mm x 130mm x 80mm / 6.4" x 4.3" x 2.7" - - Amazon.com
YaeCCC Rectangle Project Enclosure Case Electric Junction Box Blue 170mm x 130mm x 80mm / 6.4" x 4.3" x 2.7" - - Amazon.com
www.amazon.com
Robert
Reverse Engineer
Development has been set back a little since the PCB factories have all been shut down for the holiday (and now coronavirus).
The power amp module will attach to the interface board with pinheaders.
This was the first prototype, mainly just to ensure the dimensions were correct for the module to attach.
Robert
Reverse Engineer
Yes, this was just a basic input buffer with master volume control.
I did not add a toggle for the mute function, but as you can see I left the pads open on the TPA module.... I was considering wiring that to a footswitch.
One critical detail is the isolated 1/4" jacks... They need to be genuine Neutrik brand, the Chinese knockoffs are slightly wider and won't fit between the screw supports at the top. You can, however, sand or file down the plastic corners and they'll fit. (which is what I've done here)
The DC jack might be more sensible placed on the side, despite how much I am opposed to that.... I'm sure quite a few people are going to want to use a 24V supply (with relatively high current). Those are generally fatter plugs so the jack might not fit at the top.
FWIW, I put this in a 1590BB case without an additional input buffer, using a regular input jack and an isolated output jack and top-mounted power jack. I used a DPDT on-on-on toggle switch for power and mute, to be power off in the first position, second position "Standby" with power on (LED comes on with the power) and muted, and third position "On" with power + unmuted. I am pondering whether I can wire the power and mute functions to work with a bi-color LED to get different colors for Standby and ON.
I wanted to run this box off of a 20 volt laptop power supply so I also added a TO-220 9-volt regulator to power a couple of side-mounted jacks for pedals. I have the EMU amp box leading into it, and it is a good combination.
I wanted to run this box off of a 20 volt laptop power supply so I also added a TO-220 9-volt regulator to power a couple of side-mounted jacks for pedals. I have the EMU amp box leading into it, and it is a good combination.
Mike McLane
Active member
I'd love to toss a good solid state amp in the bottom of a cab loaded with REAL guitar speakers, put a preamp pedal (like a Kingsley) together with my PPCB builds and head out the door. Do you anticipate this product to serve that end?
I think you will see a few different builds with the module. What you use to power it will have a lot to do with the results you get, and it will give you something good even at 9 volts (although probably drawing more current than most effects). If you use a 20 volt laptop charger and have a 4-ohm or an 8-ohm load, it is impressive. It puts out painful sound levels in a pair of AR speakers with 10-inch woofers that are wired in parallel for 4-ohm operation. It should have no trouble driving a 2 x 12 cab (and probably a 4 x 12 cab) for a small venue, but I have not tried it.
The module will handle higher input levels than a bypassed guitar signal, so I added in a small buffer/booster board on my box to set the floor for a bypassed guitar signal at a higher level. Something like this -- http://tagboardeffects.blogspot.com/2013/01/electro-harmonix-lpb1-with-trimmer.html
The module will handle higher input levels than a bypassed guitar signal, so I added in a small buffer/booster board on my box to set the floor for a bypassed guitar signal at a higher level. Something like this -- http://tagboardeffects.blogspot.com/2013/01/electro-harmonix-lpb1-with-trimmer.html
Mike McLane
Active member
I'm REALLY anxious to see something come from this. Any thought given to bass players who may need something with higher output? I play bass quite frequently and something for a small powered bass cab (200W +\-) would be equally appreciated.
Mike McLane
Active member
Any headway on the TPA3118 front?!?!?!?!
While I will certainly go for a complete project when available, I have ordered one of the TPA3118 boards now to play with. I see that it needs a preamp to function correctly. Would my Line 6 HX Stomp qualify? Or do I need something else? Like what? I am willing to build something if needed, but I also have various boost pedals (SHO, AMZ MOSFET Booster, Emerson Paramount) and since I saw someone mention the LPB1 here, I thought maybe one of those would do the job. Please let me know what you think.
I think I’m this case “preamp” refers to a tone shaping circuit, since electric guitar amps have a lot of tone shaping (eq and/or distortion), and this amp module is just flat, so your plain guitar will sound thin and sterile.
I don’t think a boost will be necessary volume wise, just look for tone shaping, so maybe like an Emu, or Son of Ben maybe with a cab sim too. I haven’t tried any of these, just going by what folks have said.
I don’t think a boost will be necessary volume wise, just look for tone shaping, so maybe like an Emu, or Son of Ben maybe with a cab sim too. I haven’t tried any of these, just going by what folks have said.
If all it needs is tone shaping, then running my HX Stomp into it should be fine. But I also read some people saying that there was an impedance issue, and that running a buffer / preamp was the solution. Not being an engineer, that is above my pay grade.
bretvh
Member
I built one of those boards up into an enclosure and didn't really notice any impedance issues. It is very flat, EQ-wise, but even running our ol Tech21 Sansamp through it made a huge difference. The Fender settings sounded really good! Note that for optimum volume, you'll want the highest power supply it's rated for. I think I did a 24v one, but I'd have to check to confirm that. You also will get the most output going into a 4ohm speaker. I ran mine into a 16 ohm, and while it was loud, it was not really "keeping up with a drummer" loud. I imaging going into an 8 or 4 ohm would change the game quite a bit. But, for comparison, my wife's Princeton Reverb RI is much louder than this thing going into a 16ohm speaker.
bretvh
Member
BTW, in case you haven't found a schematic, I based mine off of this one:
https://i.redd.it/nwofw4ve4g921.jpg
Note that I omitted the 4700u cap. I tried with and without and didn't notice much of a difference in the noise floor. ymmv.
https://i.redd.it/nwofw4ve4g921.jpg
Note that I omitted the 4700u cap. I tried with and without and didn't notice much of a difference in the noise floor. ymmv.
Thanks for the details on your experience. So if the SansAmp made it sound good, I imagine my HX Stomp with amp (and maybe with or without) cab modeling should sound pretty good. I will report back once I have it in hand and set up.
One more thing -- is the isolated ground on the output jack the only trick I need to know?
bretvh
Member
The only other thing that comes to mind is if you get the 24v, 3amp power supply, make sure all of your components (ac inlet especially) are rated for that much current. I think I went with some metal 2.1mm, center positive metal ones that fit my power supply, I believe.
You read my mind - than you so much for sending that link. I assume the diode is simply to prevent reverse DC, and as you mentioned the electrolytic cap is probably just some additional filtering (which may not be needed). And the inout cap? Block possible DC on the input? that's probably optional as well, but I can afford to include it
BTW - doesn't 4700uF seem like a crazy high value to you?
bretvh
Member
You read my mind - than you so much for sending that link. I assume the diode is simply to prevent reverse DC, and as you mentioned the electrolytic cap is probably just some additional filtering (which may not be needed). And the inout cap? Block possible DC on the input? that's probably optional as well, but I can afford to include it
BTW - doesn't 4700uF seem like a crazy high value to you?
Yeah, in the forum post the person who designed that circuit was talking about filtering out AC. And yeah, I ordered some of those caps thinking I'd use the and they are gigantic!
I just built mine up (except for the power plug). I am a bit confused about the DC power, as the schematic you linked me to shows the negative side of the DC supply going through the cap to the positive side, with no path to ground. And, you mentioned that you omitted the 4700uF cap. So, how exactly did you wire up the DC plug. Diode goes to the positive power on the board, that part is clear. But what about negative from the DC plug - where does it go? To the chassis (perhaps by way of the input jack ground lug)?
Also, does heat become an issue? Should I drill some ventilation holes in this box, or will it be OK as-is?
Here are some photos of mine so far. I'd love to see yours as well.
I may add a power switch at some point, but I want to get it working first
Thanks for your help.
Steve
