Bjornar

I have found a work-around for the hum-problem. Simply disconnect the power from the left speaker. The sub in the left speaker will no longer play any bass, but the right one will. The hum will be gone. Since most system only use one sub, this might work fine for some of you. Some experiment with the cross-over settings might be useful for best bass from the system.

Anyone got the Klipsch ksp-400 service manual or a link for downloading it? I got the hum-problem. The hum starts when the amplifier turns itself on. The hum is gone after a few minutes, but so is the sound from the sub-woofer. Thinking about either repairing the amplifier or bypassing it and connect all the speakers to en external amplifier.

The amplifier is OK. I testet another set of speakers, and all the tests gave me the correct answer. Since the phase test for the bass with both spakers active (stereo) went fine with the Klipsch speakers, the problem with phase in the midtones should indicate an internal phase problem between the elements in the speaker? I could check the internal wiring, but maybe it is easier to use bi-wiring on one of the speakers and change the phase on the midtones? I expect it to be less risky than opening the speaker. The speakers are old, and out of warranty. I also have the humming issue, but I guess there is no connection between this and the phase problem?

I ran this test: https://www.audiocheck.net/audiotests_polaritycheck.php. Rumble and 75Hz tone went fine with cabling according to color codes. The Guitar test should place the guitar in the middle with correct phase, but the guitar was spread out. The out-of-phase test gave the correct result.

I have 2 Klipsch KSP400, and while doing a phase test, I noticed I can not get the midtown and the bass in phase at the same time. What can cause this, and how to I resolve the problem? I use single wiring of the of the cables to the speakers. Could bi-wiring with different phase correct the problem? I tested the amplifier with the same cable on another speaker, and that went fine.