[Russtafarian]

Yesterday I reworked my SB3 analog mod in order to try out the Vishay MKT1822 caps that have recently been discussed around here.  The caps are small enough to get a 1uf bypassed with a 0.033uf per channel shoehorned into the slim case.  I’ve only listened to it for a few hours and it sounds very promising so far except…

I’m getting this low level electronic chattering noise in the left channel at the start of each track.  It usually goes away within five to ten seconds but sometimes reappears later on.  Anyone heard this before or have a guess as to what it might be?

My suspicion is that the wires from the DAC output to the coupling caps are picking up the noise.  The wires are only about 2 inches long but to keep the lengths short I didn’t twist or braid them together.  The wires do “fold up” inside the case when I put it together so there’s a good chance they are squished up against the wireless card or some other noise generating component.

For the record, I’m using the SB3 in wireless mode and am powering it with a DIY LT1086 based linear PS.  I get the same noise whether I use the stock switching PS or the linear PS.

Any ideas or suggestions?

Thanks.

Russ

[DSK]

...My suspicion is that the wires from the DAC output to the coupling caps are picking up the noise.  The wires are only about 2 inches long but to keep the lengths short I didn’t twist or braid them together.  The wires do “fold up” inside the case when I put it together so there’s a good chance they are squished up against the wireless card or some other noise generating component....

I seem to recall reading somewhere (on AC ?) that the wireless module turns off when the SB is used with ethernet cable. Perhaps try temporarily using a cable rather than wireless and seeing whether the interference disappears?

[bluewax]

I had that exact same problem develop in my analog-mod SB2, and never was able to resolve it in wireless mode... ended up drilling a hole in my floor and running Cat6 cabling from the adjacent room. From what I've read, the wireless cards are touchy over time. DSK's suggestion is a good one.

[gitarretyp]

I also had a similar issue with my sb3, and it was the wireless card. Judicious routing and twisting of wires helped.

[Russtafarian]

Well that was easy.  Last night I put the SB on a cable and all the noise disappeared.  It's not just less noisy, it's spooky black quiet!  I also found the menu and track selection response to be quicker and surer. 

I was using wireless more out of convenience than necessity.  Since my SB is an easy 25 foot cable run from my router, no more wireless SB for me.  Thanks all.

Russ 

[gitarretyp]

If you're not going to use it, it's a simple matter to remove the wireless card from the sb. I didn't notice any difference in sound, but it frees up a little space and provides peace of mind.