Original caps are 18000uf 56v per channel.
I read around diyaudio forum and other forums, still a bit confused which would be best to use? or had experience with
CDE 380LX - cheapest of the lot
UCC SMH/KHM - seems to be used more
Panasonic T-UP - can still get some of these
Natually element14 and RS have limited but do stock the CDE, UCC in higher value 22000uf, and a mix of Kemet and Epcos. Digikey and Mouser have the others
CDE:
ESR: 23 mOhms
Ripple Current: 9.4 A
UCC KMH maxium esr 0.013 ripple 5.58
Panasonic
ESR: 23 mOhm @ 120Hz
Ripple Current @ Low Frequency 9.41A @ 120Hz
Ripple Current @ High Frequency 10.82A @ 10kHz
I read around diyaudio forum and other forums, still a bit confused which would be best to use? or had experience with
CDE 380LX - cheapest of the lot
UCC SMH/KHM - seems to be used more
Panasonic T-UP - can still get some of these
Natually element14 and RS have limited but do stock the CDE, UCC in higher value 22000uf, and a mix of Kemet and Epcos. Digikey and Mouser have the others
CDE:
ESR: 23 mOhms
Ripple Current: 9.4 A
UCC KMH maxium esr 0.013 ripple 5.58
Panasonic
ESR: 23 mOhm @ 120Hz
Ripple Current @ Low Frequency 9.41A @ 120Hz
Ripple Current @ High Frequency 10.82A @ 10kHz
Last edited:
Thank you Anti, Phase, Rsavas and Samsara
@ Phase i saw the Epcos they are screw in and huge, but googling the model number it is very good, will not fit in the Technics SU-V9
Low ESR and High Ripple is what i am looking for. You see the audiograde KGs never really have esr or ripple readings usually with mouser and when they do they dont seem as high as the general purpose ones
@ Phase i saw the Epcos they are screw in and huge, but googling the model number it is very good, will not fit in the Technics SU-V9
Low ESR and High Ripple is what i am looking for. You see the audiograde KGs never really have esr or ripple readings usually with mouser and when they do they dont seem as high as the general purpose ones
I would have thought the largest physical dimensions (height and diameter), and the connection style (and spacing) would have been key parameters to post ?
Do you want to consider service life ratings (ie. operating hours at a max temp at max ripple rating)?
Do you know the ripple current rating of the original model cap? If you don't then perhaps its wise to estimate that value first - eg. using PSUD2.
Do you want to consider service life ratings (ie. operating hours at a max temp at max ripple rating)?
Do you know the ripple current rating of the original model cap? If you don't then perhaps its wise to estimate that value first - eg. using PSUD2.
"Audio grade" is just a Marketing label, quite unrelated to actual measurements
I think so, in power supplies I think anyway
The Technics Su-V9 caps look in perfect condition. I dont think there is any green, any seen in the photo could be the writting on the board.
Dimensions of the old caps
35mm x 82mm
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
think its just glue, some green
An externally hosted image should be here but it was not working when we last tested it.
If you are curious about the Equivalent Series Inductance (often abbreviated ESL) of your big honkin electrolytic capacitors, it turns out you can measure ESL, yourself. I show a homebrew test jig which does exactly that, in (this discussion thread). Dinky little 2" by 4" PCB.
I'll reiterate here, the offer I made in post #13: If you mail me your capacitors, I will use my test jig to measure their ESL, at no charge. If you want me to mail the capacitors back to you, include return postage.
I'll reiterate here, the offer I made in post #13: If you mail me your capacitors, I will use my test jig to measure their ESL, at no charge. If you want me to mail the capacitors back to you, include return postage.
Thank you Trobbins. If the big old caps need changing i will go with KMH then, i am after longivity and the good sound
. I dont intend to recap for a least 10 years, after all the old caps lasted some distance. I choose PWs FRs all high 105c caps and long hoursThank you Mark for the kind offer.
I had a look, I like your little ESL board you made. High end parts on it FGs. In Australia, on ebay for 14$ cheap ESR meter, like the one I saw on EVVblog on youtube? maybe i could use this
do i have to decharge the big cans? or measure in circuit? With the Technics SU-V4X i just removed the old caps and put them on another V4X board since i damaged the other without any bangs or trouble.
The V9 on the 82db sentitivy small SL-6 bookself speakers gave great bass, and overall sound so maybe the big cans are fine. Amp itself not working atm, on and off working i suspect those tiny caps i had to changed and one thyristor going open when i tested it - removing it small break in silicone pad was noticed
Last edited:
I didn't have any time before to support the comparison between an 85C cap with a certain lifetime at a given max ripple current, and a 105C cap with a different ripple current rating and lifetime.
The most supported comparison is a doubling of life for a 10degC lowering of max temp. So the 105C at 2khr lifetime is equivalent to a 85C 8khr lifetime for the KHM part. But we don't have apples to apples with ripple current ratings.
Ripple current is the dominant internal heat generator, and given an ESR, causes an internal power dissipation. That power loss, and the internal thermal resistance from the middle of the cap to the outer cover adds to the 85C or 105C ambient, to give a max internal temp condition that the internal chemistry is designed to handle.
If the rated ripple current of say the T-UP cap is 200% of the KHM, then operating with the max ripple current for the KHM would cause a lower internal max temp in the T-UP, and hence a likely longer lifetime. The Cornell Dubilier app note provides some example values. I'd be guessing circa 50% longer lifetime for the T-UP (eg. 4khr to 5khr lifetime at 85C at 50% of its ripple current rating.
The ball-park comparison at 85C and 5.7A ripple would then be:
UCC KHM 8000hr
Panasonic T-UP 4 to 5,000hr
But note that the T-UP part is really limited to an 85C ambient only, so may get stressed if stuck in a hot amplifier.
http://www.cde.com/resources/catalogs/AEappGUIDE.pdf
The most supported comparison is a doubling of life for a 10degC lowering of max temp. So the 105C at 2khr lifetime is equivalent to a 85C 8khr lifetime for the KHM part. But we don't have apples to apples with ripple current ratings.
Ripple current is the dominant internal heat generator, and given an ESR, causes an internal power dissipation. That power loss, and the internal thermal resistance from the middle of the cap to the outer cover adds to the 85C or 105C ambient, to give a max internal temp condition that the internal chemistry is designed to handle.
If the rated ripple current of say the T-UP cap is 200% of the KHM, then operating with the max ripple current for the KHM would cause a lower internal max temp in the T-UP, and hence a likely longer lifetime. The Cornell Dubilier app note provides some example values. I'd be guessing circa 50% longer lifetime for the T-UP (eg. 4khr to 5khr lifetime at 85C at 50% of its ripple current rating.
The ball-park comparison at 85C and 5.7A ripple would then be:
UCC KHM 8000hr
Panasonic T-UP 4 to 5,000hr
But note that the T-UP part is really limited to an 85C ambient only, so may get stressed if stuck in a hot amplifier.
http://www.cde.com/resources/catalogs/AEappGUIDE.pdf
Last edited:
Attachments
Original caps are 18000uf 56v per channel.
I read around diyaudio forum and other forums, still a bit confused which would be best to use? or had experience with
CDE 380LX - cheapest of the lot
UCC SMH/KHM - seems to be used more
Panasonic T-UP - can still get some of these
Natually element14 and RS have limited but do stock the CDE, UCC in higher value 22000uf, and a mix of Kemet and Epcos. Digikey and Mouser have the others
CDE:
ESR: 23 mOhms
Ripple Current: 9.4 A
UCC KMH maxium esr 0.013 ripple 5.58
Panasonic
ESR: 23 mOhm @ 120Hz
Ripple Current @ Low Frequency 9.41A @ 120Hz
Ripple Current @ High Frequency 10.82A @ 10kHz
The best caps to use will be the ones already in your amp. Please don't waste your money. The chances of there being anything wrong with those caps is about the same as your chance of being struck by lightning...tomorrow. Just giving you the benefit of 30 odd years experience in the repair trade...
Thank you Mark. I would need a local tech with an ESL meter,not sure many would have a 30K analyzer
Thanks for the link Bill.
Thank you Trobbins, for the indepth explanation. I tried to choose 105 for the smaller caps also. I would definitely go the KMH.
Thank you Aldor. They look perfect, smaller caps i have changed.
Not sure this thread will allow me to post images relating to the layout but techically it is, to do with parts though.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
An externally hosted image should be here but it was not working when we last tested it.
above main pcb - mix FR, SU biplolar, PW and Wima
An externally hosted image should be here but it was not working when we last tested it.
part of the pre drive
VCC bypass i was told was C330, 329 to increase 33uf to at least 100uf, low esr type, so KZE seems lower esr than PW,
FR seems low though
using on this pre drive board mix of kze, pw, su bipolar,
- Status
- This old topic is closed. If you want to reopen this topic, contact a moderator using the "Report Post" button.