You have been busyÃ¢â‚¬Â¦
I think they are Class-D amps with high and low pass filers for speakers and woofer respectively
Some other ideasÃ¢â‚¬Â¦
#1 Have a barrel connector on the back of the unit that a 12v wall wart can plug into and use that to power it; I would leave the OEM supply
in the woofer enclosure, but not hooked up so that the airspace is not any larger since itÃ¢â‚¬â„¢s all a tuned enclosure (with a port). Also make sure the enclosure is sealed up very well.
#2 Use the same barrel connector, but with a 19v wall wart and then have a DC-DC converter inside the unit to go from 19v-9v (probably over kill).
I would guess (since I have not done any testing) that they best/easiest method would be #1; the single 12v external wall wart.
If this does catch on and people like it, then perhaps we could make a parts list to have a harness to go from the 5-pin Molex (in the enclosure)to a barrel connector and/or supply
a kit. I saw some pretty scary conversions on the HD1000 with the Morex PSU so this would help curb that.
Then a user could just order the parts from Digi-Key or what have you and be set.
One question that I wonder about is why there was two rails in the first place. I canÃ¢â‚¬â„¢t help but think there was a reason that Roku did a 19v and 9.5v rails verse one 12v. Perhaps since it was being designed from the ground up is why (to be more efficient)? I have a nice little 12volt wall wart for an external hard drive in my hand right now, that would fit the bill; itÃ¢â‚¬â„¢s not too big, not too heavy and is rated at 12v 2amp. From looking at where you could tap into the enclosure with the barrel conenctor, I would assuem that a wall-wart with a 90degree end would work best.
I may change my tune in 6months or so, but I am going to just fix the OEM supply
for the time being.
One last question, how was the AM and/or FM radio portion? Any noise from the 12v supply
Anyway, great work and this may be a great option once you get some hours behind it to prove there are no strange issues and/or it will hold up (to which I see no reason it will not). Regards, Matt
EDIT: Just remembered there is no molex inside for the DC portion. Let me ponder a tad...
I think I got it now.
19V Audio Amp: There are three audio amps, two inside the small stereo speaker cabinets within the display unit (they really are active bass reflex sytems!), and one amp within the woofer/PSU unit. The audio amp's power rail is directly connected to the 19V of the PSU and distributed to the two stereos and the woofer. The audio amps operate without any distortion down to about 5.5V, below they just stop working.
9.5V Microcontroller Voltage:
As mentioned earlier, there's a CM2596 switching regulator down to 5V.
The CM tolerates 7-40V input. However, the cap parallel to the CM input is a 25V only.
There's no reason to have two separate 19V and 9.5V.
The 19V can be down to 5.5V
The 9.5V can be up to 25V
I can confirm this because I operated both voltages with a single 12V,
and the radio was working perfectly, no loss in audio or WLAN receiver performance. The total operating current (audio and microcontroller climbed together to 12V) is about 550mA. At 6V about 1000mA
So I will buy a 12V switching PSU which fits into the bass speaker cabinet. Something not exceeding 110 x 60 x 45mm will fit into the original plastic/alu/copper shielding bricolage, I found some (12V, 30W) for about 25 EUR. Notebook PSUs are too long.
Roku3 and Roku HD1000 [Rev B] on a Samsung HLP5674W DLP in the living room; a Roku2 and two Roku XS and a few SoundBridges.Win7; Kubuntu and XP via RT-N66U, E2000 and a switch or two. I own stock in Roku, it's just all in the form of hardware.Viva la Roku