Dear members,
A while ago i bought a Braun csv1000/1 amp in a secondhand store.
Since i have a pre-amp, i thought, well i can use only the braun power amp.
So i removed the pre-amp and added connections for power and line input.
Then a strange thing occured. The power amp sounds good , well that is only for a few minutes. The overheating protection switches one channel off. I tried to adjust the output stage current, but no positive result. Does anyone have a clue to solve this problem ?
I also want to mention that i replaced the capacitors and trimming potmeters on the circuitboard.
I hope someone can help me out.
CSV1000/1 overheating problem in outputstage
Problem solved
Dear members,
After checking the connectors on the power amp printboard, i noticed that the null wire of the power supply was not connected to the pcb. Probably my own mistake, oops.
But i am glad i found it. The cooling elements of both channels stay cold now.
The dc current in the final stage is set to 35mA in idle mode.
And the amp sounds really good !
I was wondering, has anyone tried to replace the output capacitors with higher values. Like 10,000uF or so ?
Thank you for reading this.
After checking the connectors on the power amp printboard, i noticed that the null wire of the power supply was not connected to the pcb. Probably my own mistake, oops.
But i am glad i found it. The cooling elements of both channels stay cold now.
The dc current in the final stage is set to 35mA in idle mode.
And the amp sounds really good !
I was wondering, has anyone tried to replace the output capacitors with higher values. Like 10,000uF or so ?
Thank you for reading this.
output capacitors
Dear members,
I heard from the local electronic parts dealer, that it's no use to replace the output capacitors with higher values.
The capacitors block the dc current, so only ac current goes to the speaker.
He said that even if the value has dropped from 3,000uF to 2,000uF, because of aging, it's still good enough.
These capacitors are not manufactured anymore, he told me.
You can replace them with two anti-parallel connected electrolytic capacitors, but the quality is less.
I hope this info is usefull to anyone,
Best regards.
I heard from the local electronic parts dealer, that it's no use to replace the output capacitors with higher values.
The capacitors block the dc current, so only ac current goes to the speaker.
He said that even if the value has dropped from 3,000uF to 2,000uF, because of aging, it's still good enough.
These capacitors are not manufactured anymore, he told me.
You can replace them with two anti-parallel connected electrolytic capacitors, but the quality is less.
I hope this info is usefull to anyone,
Best regards.
Hi Acrobat,
it's nice to know that you are enjoying your CSV1000/1. However, it is not only wrong, what your electronics dealer has told you. But it has even been a dangerous advice for your electrolytic capacitors (elcaps) and for your amp.
First of all: the necessary elcaps with screw fixing are of course still available. In my own CSV1000/1 I replaced the old elcaps with 3'000 µF through new ones with 4'700 µF. The size of the new elcups is not bigger than that of the old ones with 3'000 µF. It doesn't benefit the quality of sound to increase the capacity higher than 4'700 µF.
Your dealer's advice to replace alternatively the old elcaps with anti-parallel connected elcaps would cause quite harmful affects to your amp. This would mean that in any case one of the two elkaps would have a wrong polarity and would therefore be destroyed. Thus, other components in the output stage of the amp could be negatively affected.
Couldn'd you order such spare parts via internet shipping?
It would be very nice, if you'd tell us your first name, and perhaps, where you are coming from.
Greetings Heinrich
it's nice to know that you are enjoying your CSV1000/1. However, it is not only wrong, what your electronics dealer has told you. But it has even been a dangerous advice for your electrolytic capacitors (elcaps) and for your amp.
First of all: the necessary elcaps with screw fixing are of course still available. In my own CSV1000/1 I replaced the old elcaps with 3'000 µF through new ones with 4'700 µF. The size of the new elcups is not bigger than that of the old ones with 3'000 µF. It doesn't benefit the quality of sound to increase the capacity higher than 4'700 µF.
Your dealer's advice to replace alternatively the old elcaps with anti-parallel connected elcaps would cause quite harmful affects to your amp. This would mean that in any case one of the two elkaps would have a wrong polarity and would therefore be destroyed. Thus, other components in the output stage of the amp could be negatively affected.
Couldn'd you order such spare parts via internet shipping?
It would be very nice, if you'd tell us your first name, and perhaps, where you are coming from.
Greetings Heinrich
Hi Marcel,
in the power supply of my CEV 1000/1 (behind the voltage stabilisation) I used a screw-mounted elcap 4'700µF/100V.
But you won't find a screw-mounted elcap 820µF (or 1'000µF) /160V (behind the rectifier). Neither Thomas (p1i) nor myself have found such a capacitor, not even with quite differente suppliers. Anyhow, should this elcap really be defective, are there various possibilities to replace it.
One option is to open carefully the cap at its upper site by unflanging the upper edge of the aluminum case without damaging the edge and the rubber-covered top with the connection pins. Then empty completely the casing und clean it well. The inner volume of the case should be big enough to contain 4 elcaps 220µF/160V (with radial leads). Take care for good insulation of the elcaps' connection leads and connect them via flexible insulated wires to the connection pins on top. Close the case by flanging again the upper edge of the aluminum case and take care for a nice and smooth edge.
An other option would be to take the 4 elcaps 220µF/160V (also with radial leads), place them on a experimental board (about 3,5 x 6,5 cm) and connect them (all parallel) to two soldering terminals on top of the board. Fix it standing vertically with a mounting angle with screw and nut at the same place as the old elcap was.
In any case you should renew these elcaps only if they are really defective or have lost more than 20% of their nominal capacity.
Best regards,
Heinrich
in the power supply of my CEV 1000/1 (behind the voltage stabilisation) I used a screw-mounted elcap 4'700µF/100V.
But you won't find a screw-mounted elcap 820µF (or 1'000µF) /160V (behind the rectifier). Neither Thomas (p1i) nor myself have found such a capacitor, not even with quite differente suppliers. Anyhow, should this elcap really be defective, are there various possibilities to replace it.
One option is to open carefully the cap at its upper site by unflanging the upper edge of the aluminum case without damaging the edge and the rubber-covered top with the connection pins. Then empty completely the casing und clean it well. The inner volume of the case should be big enough to contain 4 elcaps 220µF/160V (with radial leads). Take care for good insulation of the elcaps' connection leads and connect them via flexible insulated wires to the connection pins on top. Close the case by flanging again the upper edge of the aluminum case and take care for a nice and smooth edge.
An other option would be to take the 4 elcaps 220µF/160V (also with radial leads), place them on a experimental board (about 3,5 x 6,5 cm) and connect them (all parallel) to two soldering terminals on top of the board. Fix it standing vertically with a mounting angle with screw and nut at the same place as the old elcap was.
In any case you should renew these elcaps only if they are really defective or have lost more than 20% of their nominal capacity.
Best regards,
Heinrich
Hi Heinrich,
Thank you for your post and advise!
I was checking Conrad for elcaps and found a brand called FTcap.
It's a german company specialised in elcaps.
Regarding their website ftcap.de , they can deliver elcaps on request, even small amounts. Maybe even 1000uF 180V/200V ?
Conrad has only a few screw-mounted elcaps (of FTcap).
Hope this post is helpfull,
Best regards,
Marcel.
Thank you for your post and advise!
I was checking Conrad for elcaps and found a brand called FTcap.
It's a german company specialised in elcaps.
Regarding their website ftcap.de , they can deliver elcaps on request, even small amounts. Maybe even 1000uF 180V/200V ?
Conrad has only a few screw-mounted elcaps (of FTcap).
Hope this post is helpfull,
Best regards,
Marcel.