I connected the various SB3 outputs to my PC via a Tascam US-122L USB audio interface. The PC acted as a spectral analyser, the relevant results are in the image below (each Y division = 3dB). What I do not understand is why the bass response increases by 9dB at 20-30Hz on the phono and coax outputs, but not the 3.5mm output. Points worth noting:
- Same problem with two different SB3s
- Same problem with two different pink noise files: one was from Inguz (44KHz / 16bit flac), and the other from www.24bit96.com
- You can see the problem creeping in at about 500Hz
- The coax was tested via a Rotel RSP-1068 surround pre-processor.
I dont understand this and I cant help but think I am doing something truly stupid. I would have thought the problem would be audible as I have a pretty decent system, but I have never noticed it although I may well have unwittingly tuned it out as I normally apply a cross over at 60Hz for a subwoofer (no filters for this test).
Any ideas anyone? I am running LMS 7.9.2 on a Raspberry Pi4 (its great!).
![Name: SB3 noise, Upstairs, green=3.5mm left, red=phono L (resize 75%).jpg
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- Same problem with two different SB3s
- Same problem with two different pink noise files: one was from Inguz (44KHz / 16bit flac), and the other from www.24bit96.com
- You can see the problem creeping in at about 500Hz
- The coax was tested via a Rotel RSP-1068 surround pre-processor.
I dont understand this and I cant help but think I am doing something truly stupid. I would have thought the problem would be audible as I have a pretty decent system, but I have never noticed it although I may well have unwittingly tuned it out as I normally apply a cross over at 60Hz for a subwoofer (no filters for this test).
Any ideas anyone? I am running LMS 7.9.2 on a Raspberry Pi4 (its great!).