Sure Electronics TK2050 2 x 100W Power Supply

[stofmike]

I am planning to use multiple Sure Electronics TK2050 2 x 100W boards each connected to an apple airport express and a set of speakers to create a multi room audio system. I am currently running a board off an old printer power supply as a test system but want to buy a more long term solution.

I have seen users that have used a "laptop" power supply such as the one here 12V 0-3A DC Power Adapter 5-2.1mm Plug/AC 110V/AC 220V_Plastic Power Adapter_Boxed Industrial Power Adapter and Chargers and Transformers_Measure Power Adapters_Sure Electronics' Webstore but have also read that the Meanwell power supplies are really good. There is a difference in cost $13 vs $45 upwards.

Most of the time the boards will be powering background music. Therefore, what power supply should I get, the speakers will be max 100W, probably going to go with some 65W ones. I am also not an expert on sound. What power supply must I buy so that the system will work correctly? Also, how many boards can one power supply handle or should I only use one power supply per board?

[wwenze]

Max 100W @ 4 ohm, or 50W @ 8 ohm, with a 32V power supply, IIRC.

If you want 100W into each speaker then you'll need a power supply capable of supplying that 100W per speaker, so 1 board 2x100W speakers 200W power supply, 2 boards 400W power supply and etc. And the voltage needs to be 32V; any lower and you won't get the 100W per speaker.

[col]

I recently made up a 2X100W using a 12-24v DC-DC laptop PSU. It claims it can put out 5A at 24v.

Sure Electronics 2x100W + DigiTech 12-24v DC-DC inverter (laptop PSU)

col.

[Saturnus]

Originally Posted by col

I recently made up a 2X100W using a 12-24v DC-DC laptop PSU. It claims it can put out 5A at 24v.

Sure Electronics 2x100W + DigiTech 12-24v DC-DC inverter (laptop PSU)

col.

Well obviously a 24V 5A power supply won't be enough for 2 x 100W sustained output as it's only able to output 120W with real music it should be ok though.

However, it will only output 100W @ 24V if the impedance of the speakers is 3 Ohms or less, and even then it's at 10% distortion. The speakers has to be 2 Ohms or less for the amp to output 100W @ 0.1% or less distortion.

[col]

I'm using it with 4ohm 60W 90db speakers, seems to be a fairly good match.

col.

[Saturnus]

Originally Posted by col

I'm using it with 4ohm 60W 90db speakers, seems to be a fairly good match.

Yeah, that's pretty much perfect. The amp will output max 60W into 4 Ohms per channel with 24V, and the PS is able to output max 120W totals.

What I don't get is how most people think that a Sure board will output 2 (or 4) x 100W on a 12V battery. It won't ever do that as short circuit protection will kick in before the impedance gets low enough for that (0.56 Ohms total including cable resistance)

[col]

What I don't get is how most people think that a Sure board will output 2 (or 4) x 100W on a 12V battery. It won't ever do that as short circuit protection will kick in before the impedance gets low enough for that (0.56 Ohms total including cable resistance)

or worse still, the chip burns out before the short circuit protection kicks in.

col.