View Full Version : Output Coupling Cap Upgrade on SB3?

2006-09-11, 10:23
Has anyone documented this mod?

I found it for the SB2 but not the SB3. I do see that the output caps on the SB3 are 10 mfd and SURFACE MOUNTED (Uggg). Is is difficult to remove these and solder new cap leads to replace the stock caps?

Seems an ideal cheap mod would be to route the audio directly from the dac through PIO caps to the RCA jacks. I would think this would be the best bang for the buck and provide 80% of the benefit of those other $300 mods out there.

Anyone tried this?

2006-09-11, 12:22
I tried this and the difference is very noticeable. Keep in mind that the load on the DAC must be 5K ohm or higher.

2006-09-12, 00:57
Have a look here.


GaryB reported various SB3 mods with pictures. His analogue mod does exactly what you are suggesting - directing the signal directly from DAC to RCA via blackgate caps. He also removes the op-amp stage.

I'll be giving this a go soon. Have the blackgates ready. Just want to finish my linear power supply first.

Will be interested to hear how you get on if you try this and what improvements you hear.

2006-09-13, 23:32
I read through Gary's sb3 mods and began them myself this evening, however the link to the sb2 schematic is not working. Does anyone have a schematic? The reason I ask is that the internals of my SB3 differ from the SB3 photos documented in the thread, and I really don't want to start cutting and removing caps without being sure.


2006-09-30, 11:38
Attached is a zipped file (zipped pdf of squeezebox 2 schematic.zip) containing squeezebox 2 schematic.pdf

This had to be inside a zip file due to a pdf file size limit for this forum

Have fun.

See also this thread for hints and info: http://forums.slimdevices.com/showthread.php?t=23687

If space is limited, I would go with paired non-polar black gates where each pair is arranged in an L-Canceling configuration. See Note 1 of the above thread. Otherwise, I finally settled on $14.95 AURICAPs (15/16-inch diameter by 1-inch long).