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Old 3rd August 2006, 07:54 PM   #21
fredos is offline fredos  Canada
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Why you dont keep the original cap onboard to lower the ESR???

Keep leg of capacitor shorter than you can!

fredos

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Old 4th August 2006, 03:29 AM   #22
ghemink is offline ghemink  Netherlands
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Quote:
Originally posted by fredos
Why you dont keep the original cap onboard to lower the ESR???

Keep leg of capacitor shorter than you can!

fredos

www.d-amp.com

Hi Fredos and others,

I was almost going to say the same thing. I would keep at least some capacitance on board so that the worst current/voltage spikes are kept on the PCB instead of going via those wires to the jensen caps and in the meantime emit rubbish. Maybe you want to get rid of those 2x3300uF caps per rail on board as you maybe afraid that the total capcitance is becoming too large? I have added an additional 10000uF ELNA cerafine offboard (per rail) (keeping the original caps), and the supply has no problem with that (no startup problems at least, have not checked full functionality when loaded with amps that give a varying load).

Another option could be to remove just one of the caps on the supply itself (so keeping one), or remove both of them and replace them with high quality smaller ones if the large total capacitance is a concern.

Best regards

Gertjan
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Old 4th August 2006, 06:24 AM   #23
ssanmor is offline ssanmor  Spain
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Most people is vey happy with the sound using the SPS80 as it is from the factory, but if you want to add audiophile caps, I would also recommend to keep leads as short as possible and keep some capacitance on board, or EMI / regulation could be adversely affected, as Gertjkan and Fredos have suggested wisely.

Sergio
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Old 4th August 2006, 08:40 AM   #24
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What is the maximum capacitance one can add without removing the onboard caps?
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Old 4th August 2006, 08:44 AM   #25
ssanmor is offline ssanmor  Spain
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We don't recommend to add more than 10.000uF more per rail, in fact we think it is totally unnecessary to increase capacitance; have in mind that a switching power supply "refreshes" the capacitor charge at around 1000 times the rate of a linear PSU, so the "bare" onboard 6600uF per rail should be more than enough even for the most demanding loads.
Measured ripple at 800W load is around 1Vpp per rail with the standard caps. (!!!) Try to achieve that with a linear PSU ;-)

Best regards
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Old 4th August 2006, 07:36 PM   #26
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"a switching power supply "refreshes" the capacitor charge at around 1000 times the rate of a linear PSU"

Very interesting; I hadn't fully appreciated that important advantage before - whereas a linear supply needs enough transformer and capacitance to keep up with current demand, the switching supply needs much less of the latter.
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Old 5th August 2006, 08:30 AM   #27
la1209 is offline la1209  Hong Kong
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My SPS80's output cap is 4700uF/63V, I found that the performance is much better than the original cap. Much more muscial, stronger bass, more sweet in the mid-range!
Very positive result after modified the output caps to Jensen 4-pole.
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Old 5th August 2006, 12:50 PM   #28
ssanmor is offline ssanmor  Spain
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Customers are very satisfied with the standard version sound, but anyway it's nice that you have found an inprovement with your caps. If you tell us the brand and model, perhaps we can start offering a audiophile series of the supply after testing it extensively.

Best regards,
Sergio
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Old 5th August 2006, 03:19 PM   #29
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I think he is using this type

http://www.jensencapacitors.com/audi...ers/4pole.html

http://www.referenceaudiomods.com/Me...ory_Code=JE4PA
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Old 5th August 2006, 04:00 PM   #30
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Maybe it would be possible to instead offer multiple footprints to enable different caps to be used, either four pole or not.
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