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How are you getting around these boards blowing at 24v? I'm also getting a lot of hum with mine when it's paired with a particular pedal that has a switchable 9->18v chargepump. The pedal is powered from a 1spot, and the amp is powered by a laptop supply @19v. It's starts off relatively quiet...

Yeah, you can't ground the output to the enclosure. First google hit: "That's because most amps and receivers these days have bridged (or differential) output. Both the negative terminal and positive terminal of bridged output amplifiers send a voltage signal to the speakers, so there is no...

Ok, further updates: I boxed up the big red 150w PCB in the usual manner - input, buffer, volume pot, buffer, amp - and found it way too noisy. The 24v supplies I've gotten have a high pitch, low volume noise in there with any of my amps so I'm using the 19.5v ATM, but it was pretty unusable...

I'm not using that 220n on the volume pot. Ditch it, and stick another buffer after the pot.

Heads up - the little blue 60w ones will die with 24v. One bloke found out on the DIYstompboxes(unofficial) FB group, and I had it happen to me when I tried 24v rather than 19v. The caps are rated to 25v, but clearly not really...

Good points. I'll try that.

Well, I've hit a roadbump. My 9v regulator is getting blown when I swap in the 24v PS. Not sure what's going on there. Not an issue on a straight amp build as the buffer circuit can take 24v, but I'm not sure the other circuits in my 60watt build can (the cabsim and xlr driver). Certainly...

I literally walked around the secondhand shops looking at the back of the power supplies until I found one with the required specs written on the back. Most of mine are 19v@~3.5 except for the new ones that are 24v@5a. Those are bigger than the enclosures I'm putting the amps into. Seriously...

Datasheets are here. They might have a generic schematic for using them: https://www.ti.com/product/TPA3118D2 You want the mono version of the little blue one (google: 60w mono TPA3118d2) or the mono version of the TPA3116D2 (google 100w mono tpa3116d2). Both work equally well.

Did you try putting a 4700uf across the +ve and -ve power?

The laptop ones work fine in my further experience.

My understanding is that you want your amp to have more headroom that the speaker so the speaker doesn't get a squarewave sent to it. You'll be able to try it out carefully as I was initially testing these on some little stereospeakers. As far as powersupplies are concerned, I've picked a few...

It'll push the 15w@8ohm without issue and you can fly a speaker to it, just don't run it into the amp itself. The 4x12 cab in the video I'm playing the TPA3118 into measured 15ohms, and the wedge I test on at home is 10ohm (12inch woofer + tweeter). I haven't opened it up fully but it keeps up...

I don't *know* that it matters where the buffer goes as the amp works properly with a buffered pedal in front of it but I would certainly put one between the volume pot and the amp at a minimum. I just put a buffer on either side of the volume pot to make sure the pot doesn't interfere with...

Ok, so I get a few stupid pedal ideas occasionally and things like this happen: - Direct (buffered) pass through to normal amp. - Larts Simple Cabsim to THCustoms Linedriver XLR - TPA3118 output. The volume knob only affects the TPA3118. The guitar signal is split using the vero layout I...

On the regulator? 330n between pins 1 + 2. 100n between 2 + 3. I used an IC buffer as I could use the 2 sections in a TL072. The current amp I'm building has a TL074 as a 3 way splitter, and a separate buffer. It splits to the (external) amp, cabsim and XLR driver, plus a send/return for...

It's a bit rough, does this help?

So I measured the Marshall cab in the videos above at 15ohm, and I used 100Lolwhaats!? into it today. Again, plenty of volume on tap, not noisy in the slightest. Yeah, I hook the 24v feed up to pin1 of the regulator, and to the TPA3118 straight off that pin. Pin2 goes to ground, and Pin3...

Haven't tried one, don't see why not.

I've got that power amp lying around as well. It's not bad, maybe a bit noisier than the others, certainly a bit larger. I got around the 9v problem by including a 9v regulator and associated caps on the buffer board. On my latest effort, they're mounted directly on the power socket. I've...