Hello good peoplo.
I recently acquired four zappulse modules, they are to be used in some active speakers tri-amp.
The modules are two 2.1 and two 2.2 they are for highs and mids.. By the way the modules are standard not the SE versions. My problem is that I have two nice 50 volt toroidal transformers of 1 kW each after rectifier that amounts to around 70 volts which is a bit to much the onboard caps of modules are rated 63 volts.. Could it work swapping the caps for some higher volt types and get a stabil amplifier or is it more tricky than such.. Hope there are some experts outhere
Regards thomas.
This is a link to the zappulse cookbook and it looks like the only difference is the charging caps..but better safe than sorry link is here.
http://www.lcaudio.com/pdfs/zp21mateng.pdf
I recently acquired four zappulse modules, they are to be used in some active speakers tri-amp.
The modules are two 2.1 and two 2.2 they are for highs and mids.. By the way the modules are standard not the SE versions. My problem is that I have two nice 50 volt toroidal transformers of 1 kW each after rectifier that amounts to around 70 volts which is a bit to much the onboard caps of modules are rated 63 volts.. Could it work swapping the caps for some higher volt types and get a stabil amplifier or is it more tricky than such.. Hope there are some experts outhere
Regards thomas.
This is a link to the zappulse cookbook and it looks like the only difference is the charging caps..but better safe than sorry link is here.
http://www.lcaudio.com/pdfs/zp21mateng.pdf
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I wonder why there are only 63v rated caps, no way specs are correct on that.
But I will assume they are and origin of your caps is under question.
Can you take a picture of them, on the amp?
You might only need to change them, since from the link you provided, I see one amp, that has 160v rated caps and the other one, that has poly or how are they called caps. So how you have ended with 63v ones is a good question, but since they are used amps, person before you didn't use that high voltage, probably around 50v only.
I think I would put 100 or even 160v caps in. They are only local filter, not the main bulk caps anyways
But I will assume they are and origin of your caps is under question.
Can you take a picture of them, on the amp?
You might only need to change them, since from the link you provided, I see one amp, that has 160v rated caps and the other one, that has poly or how are they called caps. So how you have ended with 63v ones is a good question, but since they are used amps, person before you didn't use that high voltage, probably around 50v only.
I think I would put 100 or even 160v caps in. They are only local filter, not the main bulk caps anyways
Hi luka..
Thx for reply.. You are right it is a bit strange..it has puzzled me the whole week.. The 63v poly caps are original.. Nothing has been tampered with.. Another and more fun side to the story is that they are actually manufactured in the town I live in.. About 2 k from where I live.. I actually think I will go knock on their door this week and get the mystery solved..can't wait to get the speaker cabs back from car painter and get the amps installed in them... Better than Christmas.. I'll get back with update on the voltage dillemma..
Thx for reply.. You are right it is a bit strange..it has puzzled me the whole week.. The 63v poly caps are original.. Nothing has been tampered with.. Another and more fun side to the story is that they are actually manufactured in the town I live in.. About 2 k from where I live.. I actually think I will go knock on their door this week and get the mystery solved..can't wait to get the speaker cabs back from car painter and get the amps installed in them... Better than Christmas.. I'll get back with update on the voltage dillemma..
If I'm not wrong, the only difference between standard and Se-version, is the de-coupling capacitors. So you may be able to run at +/- 70 VDC after changing the capacitirs to higher voltage ratings.
Be aware that the SE-version is rated at maximum 72 VDC. The no-load voltage on a rectified 50 VAC transformer may exceed this. And during heavy load, bus-pumping may cause even higher voltages.
I would go for another transformer.
Be aware that the SE-version is rated at maximum 72 VDC. The no-load voltage on a rectified 50 VAC transformer may exceed this. And during heavy load, bus-pumping may cause even higher voltages.
I would go for another transformer.
The primary of a typical audio PSU toroid is hard to access as it is internal, and secondaries are external. There is a clean shortcut without dismantling the transformer, which consists on either winding some more turns in series with the primary in same direction or in series with secondaries in opposite direction, with appropriate type of wire, and proper care of insulation, this is OK for voltage reductions like 10~20%, so that not much additional inefficiency is added. There is a less clean shortcut which consists on carefully unwrapping the outer layer of insulation until the secondaries can be accessed, then finding the right end of secondaries and removing turns until satisfactory voltage is reached, then restoring insulation, for such an operation getting a roll of transformer tape (high temperature adhesive) is recommended.
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