Power Supply issue for small portable system - question!

[ligonk]

First off, hi HTGuid community! The interaction in this forum is unprecedented in it's friendliness and willing assistance, so I have come out of lurk mode to pick your brains.


I am building a small portable system for my father based off of the B3S full range driver design by Zaph. He does not like it when people alter his designs and attach his name, so lets just say it was "inspired" from his design. Essentially it is one enclosure with two volumes of air (similar to Zaph's original design) separated by a baffle. Within this I will include the two filters, a 15-watt amp from PE (Part # 320-600) some RCA-inputs and a Bluetooth Receiver (PE Part #320-351).

The amplifier states needing a 12-volt DC, 2-amp power supply and the BT Receiver states needing a 1-amp supply (12 VDC). I plan on using this 12-VDC, 2 amp power supply (PE Part #120-052) going into one of these passing the power into the box (PE Part# 335-372, it is a female plug to screw terminal adapter). From there I was HOPING to be able to take that power and split it to both the BT Receiver and the amplifier, but I don't know if that is okay to do.

In raw amperage, the max draw in the worst case conditions will be 10WX2 into 8 ohms which will be 10% THD and that is only 2.25 Amps. This plus the 1 amp from the blue tooth will overdraw the power supply, but this would only be for short bursts of energy. Program material played at this wattage would sound bad and have 0 headroom for dynamics. So i am more or less comfortable with the overal amp rating on the supply. What I am less sure about is I don't want weird resonant oscillations or feedback from having two separate circuits (of which i don't know if wither has a power-input buffer) messing each others power draw up.

The primary goal of this build is portability, so having two separate wall-warts for each device is kind of out of the question. It would be feasible to use a 5 amp power supply, but the additional size of that would be considered a large negative. I tried to find a BT-receiver+amplifier combo, but none exist at the price-point/power rating. (How do those combo units divide the power?)


At any rate, let me know what you think, if I will be okay with my power splitting, or if you have any other creative suggestions.

Thanks,

Rhokaln

I have a "question" posted on PE as well.

http://www.parts-express.com/12-vdc-2000ma-2a-switching-power-supply-us-and-eu-25mm-plug--120-052

[JonMarsh]

Power splitting is probably OK, I'd be surprised if that bluetooth module actually pulled more than 100-200mA; even that might be over estimating. 1A at 12V would be 12 watts of power dissipation- nothing on that board that would be able to handle that!

Half of DIY is just experimenting and seeing if it works... especially if there isn't enough up front information. I'd consider upgrading the power supply anyway, at least to the 3A 12V 320-312.