Hello folks,
I have a problem with the Kenwood KA-6000. Instead of describing it, I think it's better to just show you what I mean: https://www.youtube.com/watch?v=eb-FRdBor_Q
The bang at the beginning is ok, but the bumm, bumm, bumm not.
Now the story is:
1. When I remove the Pre Out/Main In Jumper both main amp and pre amp work well independantly.
2. When I hook up my Equalizer between Pre Out and Main In the amp works fine (the EQ is set to pass through so the signal isn't really effected).
3. When I push one of the Low Filter, the speaker movement fades away.
4. I replaced C304 and C307 (2x 470/25), because they were damaged.
First the problem was solved but after a week the bumm, bumm, came back.
I tested C302, C303 and C306 and they were weak so I replaced them, but it didn't make any difference.
Nevertheless the Equalizer thing works, so I use the amp for about 2 years now.
One week ago I replaced the 2SC458 with 2SC2240. I read they cause noise and after the replacement the amp was quiet (at least that was successful)
BUT the old problem was back (and even increased): now neither the Low Filter nor the EQ set on signal pass can prevent the speakers from oscillating.
I have to set the EQ on (all faders in mid position), then it works.
So the main point is: Main amp and pre amp work, but not together.
Of course I sent the device to a local hifi workshop, before I've done all this, but they said the amp is ok... well, funny thing is that the shop doesn't exist anymore...
Now I hope someone has an idea what might be the problem.
I have a problem with the Kenwood KA-6000. Instead of describing it, I think it's better to just show you what I mean: https://www.youtube.com/watch?v=eb-FRdBor_Q
The bang at the beginning is ok, but the bumm, bumm, bumm not.
Now the story is:
1. When I remove the Pre Out/Main In Jumper both main amp and pre amp work well independantly.
2. When I hook up my Equalizer between Pre Out and Main In the amp works fine (the EQ is set to pass through so the signal isn't really effected).
3. When I push one of the Low Filter, the speaker movement fades away.
4. I replaced C304 and C307 (2x 470/25), because they were damaged.
First the problem was solved but after a week the bumm, bumm, came back.
I tested C302, C303 and C306 and they were weak so I replaced them, but it didn't make any difference.
Nevertheless the Equalizer thing works, so I use the amp for about 2 years now.
One week ago I replaced the 2SC458 with 2SC2240. I read they cause noise and after the replacement the amp was quiet (at least that was successful)
BUT the old problem was back (and even increased): now neither the Low Filter nor the EQ set on signal pass can prevent the speakers from oscillating.
I have to set the EQ on (all faders in mid position), then it works.
So the main point is: Main amp and pre amp work, but not together.
Of course I sent the device to a local hifi workshop, before I've done all this, but they said the amp is ok... well, funny thing is that the shop doesn't exist anymore...
Now I hope someone has an idea what might be the problem.