I needed to find a way to jury-rig a similar effect for a fraction of the cost. Unfortunately, the asking price for that Trinnov processor is absurdly beyond my budget. The better solution is to install additional speakers in the center between the other height channels (Top Middle position). Those speakers are now fixed in place with wiring through the walls and ceiling, and I can’t move them without remodeling the room. This issue is compounded by the fact that the locations where I had installed speakers when I built the home theater (before immersive audio was a concern I gave any thought to) were less than ideal for Atmos. That, combined with a low ceiling, makes it difficult for just four speakers (two in the front of the room and two in the back) to image a sound above my head convincingly. My own home theater is a long room with a lot of space behind my seats. Thanks again.Nonetheless, for some of us, a limit of four height channels isn’t enough to fill the top of the room with sound. I read with interest your thread on your self oscillating design, very interesting, excellent PCB layout I must say. What started out as a simple repair has captured my interest in Class D amplifiers, As a processor engineers I feel there existance should not have escaped my notice for so long. The LLP package is a challange to solder to by hand but I have successfully done it before so am willing to attempt it. I have settled to fixing a National LM48410 LLP device onto the board and then wiring to the existing components that can be used ! The LM48410 is a 2 Watt device requiring few external components, it has spread spectrum PWM and requires no output filters ! I assume there is no problem with leaving the existing output filters in place, so to minimise the disruption to the board. However the beauty of this unit is that it is so small and there is very little room to fit anything above surface mount height on the board. I had toyed with the idea of incorporating a small evaluation board within the unit. I guess if all else fails I can graft another part in its place, but would prefer to put the correct part back. The analogue pre stages also appear to be functional. I have established that the processor on the unit is working and appears to be communicating with the ipod. Although an experienced electronics engineer I have had little to do with class D type amplifiers so am using this as a bit of a learning exercise. I must say I have considering this is a low cost product I am impressed with the build quality of this item and will be interested to here what sort of sound quality it produces. I threfore wondered if anybody knows which part JBL use on this product. The pinout does not seem to match the footprint of any part I can find. As far as I can establish the amplifier is a Class D type, with output filters in a 20 pin small footprint surface mount device. The audio amplifier has completely burnt out and the manufacturers logo and part number are not visible. For those of you who don't know this is a small portable iPod docking station (don't laugh). I'm trying to repair a JBL On Stage Micro for a family friend.
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