Need Help Troubleshooting

[AI401]

Hi, I am having trouble with my setup and looking for some help/suggestions. I recently set up my Bose 901 VI’s that I haven’t used in quite some time. They are hooked up to an Adcom 555 amp, Adcom GTP-400 preamp and Bose EQ. The issue is intermittent but I am getting a crackling/low muffled sound out of the left speaker. I thought it may be the RCA to 1/4 cable that I was using so I got a Bluetooth receiver. The issue still happens. I tried using all RCA’s on the preamp (tape 1, 2, CD) and same issue. Any idea of what’s going on? I appreciate any help.

 

[DonH56]

Could be a bad coupling capacitor, bias issue, loose connection inside (or outside), etc.

For starters, I would try swapping cables side-to-side (left/right) one at a time for each cable through the chain, from source to speaker (including speaker cables), being sure to power down (at least the power amp) between each change. That should narrow down what component is causing the problem as it should swap sides at some point (unless it is the speaker itself). Once you know what component is the problem, try a new cable at that point to see if it is the cable, and if not then chances are the component needs repair. Could be a bad connection or a failed (failing) component (part) inside the component.

May be an iterative process, patience is required.

HTH - Don

 

[AI401]

Thanks Don! I bought some new RCA’s swapped them and no issue on either side. It is a random/intermittent issue so I’ll have to keep using them and see if it happens again.