Samuel Groner
Well-known member
Hi
I just built this simple unbalanced mic pre with two 5534 for a friend; noninverting mode, 20 to 60 dB. After 30 min or so, both channels shut down probably due to overheating. The opamps run on +/-19 V and it is a tight case without opening. Could this alone cause the shutdown? Or is there some low-level oscillation going on? I had issues with stability (coupling from out to in as everything is so tight), but it looks like these are solved now. Now 'scope at hand right now, unfortunately, but they sound good as far as I can judge with the cheap dynamic mic it is supposed to be used.
I can post a schemo if this helps, nothing special, however.
Thanks for you help!
Samuel
I just built this simple unbalanced mic pre with two 5534 for a friend; noninverting mode, 20 to 60 dB. After 30 min or so, both channels shut down probably due to overheating. The opamps run on +/-19 V and it is a tight case without opening. Could this alone cause the shutdown? Or is there some low-level oscillation going on? I had issues with stability (coupling from out to in as everything is so tight), but it looks like these are solved now. Now 'scope at hand right now, unfortunately, but they sound good as far as I can judge with the cheap dynamic mic it is supposed to be used.
I can post a schemo if this helps, nothing special, however.
Thanks for you help!
Samuel