I would like to recap my AU41 Sugden preamp circa the 1990s. All caps are Rubycon CEW blue 85C. It is an Aluminium type. I have received a schematic from the manufacturer in England. All in situ caps match in value with the schematic one. Of course, Rubycon CEW is not available from Nord-American web store. I found on the net some cross reference, CEW series seems to be the same that the TWSS series. I read it on this web site
Datasheets & application notes - Datasheet Archive Search Engine
Should I stick to Rubycon capacitors? Can I choose another type that Aluminium one? I list classical music, especially early music, folk and jazz.
In my reacher, I crossed a new ''word'' for me: EPR.
In a forum about it, I read that Rubycon capacitors should be not good for my taste.
High End Audio - Electrolytic capacitors
I would like to stay close to Sugden spirit.
Datasheets & application notes - Datasheet Archive Search Engine
Should I stick to Rubycon capacitors? Can I choose another type that Aluminium one? I list classical music, especially early music, folk and jazz.
In my reacher, I crossed a new ''word'' for me: EPR.
In a forum about it, I read that Rubycon capacitors should be not good for my taste.
High End Audio - Electrolytic capacitors
I would like to stay close to Sugden spirit.
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That high end audio article is very strange. I would not expect observable effects from the power supply caps. If he want less aggresive sound, more "softness" he should put resistance or inductance in his supply rails before the transistor collectors, not buy a filter cap with a higher ESR . I'm more interested in scientific results like high frequency IM distortion, say the buzz one can get from 10000 hz plus 14000 hz. Nobody ever measures that, but I can hear it on top octave piano tracks with some products. I don't have equipment to do Im distortion tests, but I do have a Steinway piano to use as sound calibrator. Piano is very hard to accurately reproduce, few sound systems are up to it.
I got some harshness in my PAS2 by replacing the 1961 era paper coupling & tone control caps with polyester. Paper is no longer available, and had higher self-inductance than film that has a connection to each layer at the end. If I do it again with .198 uf polyprophylene that John Curl says is better, (I used .22 polyester), I might put a little inductor bead over the lead. I'd have to parallel .18 uf and .018 to use stock caps, .2 uf is no longer stocked.
I use Panasonic, Rubicon, Nichicon interchangeably in my organs & amps. I buy the longest service life rating industrial cap I can find, usually not less than 3000 hours, in the smaller ones 10000 hours are available. Digikey & farnell put the service life # in the selector table, mouser makes you look it up on the datasheet.
Some people obsess about 105 deg caps, and they do have more water than 85 deg ones, but did they use the 2nd grade sealant that keeps the water in for years? Sealant varies from the 500 hour **** grade in caps used by most repair shops, to the industrial caps used in top line motor drives that live in 60 deg C housings. Top grade epoxy sealant is no longer stocked, if you want a forever electrolytic cap you'll have to buy 10000.
I have not observed any power supply effects except dried up high esr caps cut peak currents available, which make an amp sound "nice" and "polite". The loss of peak power is measurable at the speaker jack. I don't want "softness", I want accuracy. A Steinway grand produces a xx db peak at the start of the note, especially on the highest notes, and I want to hear it. Very harsh. Just like the one in the church I go to concerts in.
Also buy caps from a real authorized supplier, as digikey mouser farnell maybe RS from the UK? Digikey has the smoothest cross US border experience, whereas farnell if they use US stock get you stiffed with a $20 UPS "loan origination" fee crossing the border. Ship USPS/RM if you can get it. Digikey runs their own truck from Minnesota across the border daily.
Best of luck.
I got some harshness in my PAS2 by replacing the 1961 era paper coupling & tone control caps with polyester. Paper is no longer available, and had higher self-inductance than film that has a connection to each layer at the end. If I do it again with .198 uf polyprophylene that John Curl says is better, (I used .22 polyester), I might put a little inductor bead over the lead. I'd have to parallel .18 uf and .018 to use stock caps, .2 uf is no longer stocked.
I use Panasonic, Rubicon, Nichicon interchangeably in my organs & amps. I buy the longest service life rating industrial cap I can find, usually not less than 3000 hours, in the smaller ones 10000 hours are available. Digikey & farnell put the service life # in the selector table, mouser makes you look it up on the datasheet.
Some people obsess about 105 deg caps, and they do have more water than 85 deg ones, but did they use the 2nd grade sealant that keeps the water in for years? Sealant varies from the 500 hour **** grade in caps used by most repair shops, to the industrial caps used in top line motor drives that live in 60 deg C housings. Top grade epoxy sealant is no longer stocked, if you want a forever electrolytic cap you'll have to buy 10000.
I have not observed any power supply effects except dried up high esr caps cut peak currents available, which make an amp sound "nice" and "polite". The loss of peak power is measurable at the speaker jack. I don't want "softness", I want accuracy. A Steinway grand produces a xx db peak at the start of the note, especially on the highest notes, and I want to hear it. Very harsh. Just like the one in the church I go to concerts in.
Also buy caps from a real authorized supplier, as digikey mouser farnell maybe RS from the UK? Digikey has the smoothest cross US border experience, whereas farnell if they use US stock get you stiffed with a $20 UPS "loan origination" fee crossing the border. Ship USPS/RM if you can get it. Digikey runs their own truck from Minnesota across the border daily.
Best of luck.
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Thank you for your reply. You give me another perspective: service life. But I remain confused about different series and material more than the brands. There is Aluminum, polyester ....
Yes USPS is cheaper and a lot more convenient. But now I prefer to order for the UK, it is faster and cheaper, at least with eBay. However, big electronic internet stores have a postal address in Canada.
Yes USPS is cheaper and a lot more convenient. But now I prefer to order for the UK, it is faster and cheaper, at least with eBay. However, big electronic internet stores have a postal address in Canada.
The important thing with electrolytics is to go for long-lived caps, ie the higher temperature ratings, with low ESD (means thicker foils, again a longer life factor). Any reputable capacitor brand with good specs will be fine. Panasonic and Rubycon are well respected but other brands may do just as well or better - its all in the specs and absolutely nothing to do with what kind of music you listen to!
For instance Vishay 120ATC range has good specs and is automotive rated (always a good sign for component robustness and tmperature tolerance).
For instance Vishay 120ATC range has good specs and is automotive rated (always a good sign for component robustness and tmperature tolerance).
Is this inside your AU41?
sugden preamplifier - au41 1 sugden - Hifishock
I would change the diodes. Shottky-types.
Electrolyts of the psu with more capacity too.
De-solder and re-solder complete.
The bordeaux-coloured capacities replace with any styroflex capacitors. The orange ones too?
What is "Sugden spirit"-?
sugden preamplifier - au41 1 sugden - Hifishock
I would change the diodes. Shottky-types.
Electrolyts of the psu with more capacity too.
De-solder and re-solder complete.
The bordeaux-coloured capacities replace with any styroflex capacitors. The orange ones too?
What is "Sugden spirit"-?
> Given the parallel film caps what he may be hearing is the effect of resonance, which will be worse with low ESR electrolytics.
I have a scrap image of "parallel caps" including some parasitics.
The 40uFd alone would fall to 0.5r at the top of the audio band and rise slow above 1MHz.
"40u+0.1" shows a violent rise near 330kHz. Whether that matters or not requires much study of the system PSRR and how it intermodulates supersonics down to the audio band.
And yes, if the 40u cap was lower ESR that 330kHz peak would be even wickeder.
I have a scrap image of "parallel caps" including some parasitics.
The 40uFd alone would fall to 0.5r at the top of the audio band and rise slow above 1MHz.
"40u+0.1" shows a violent rise near 330kHz. Whether that matters or not requires much study of the system PSRR and how it intermodulates supersonics down to the audio band.
And yes, if the 40u cap was lower ESR that 330kHz peak would be even wickeder.
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I think "....in the spirit of Sugden..." is to use any of the recommended long-life grades suggested here. The manufacturer buys components by specification - they won't be sitting down listening to all the available types in a prototype model unless there is a change of spec. or anomaly in the pre-production model that their attention is drawn to.
The opinions you read on audio forums about the sound quality with various caps is mostly sillyness, particularly when someone is comparing 29 year old caps with new ones of 4 times the value, as I read recently. Unfortunately, some amateurs, even those with strong opinions, still don't have a clue about what they are doing or talking about when they make comparisons with hours, days or even years between making their A-B assessments and often with entirely different amplifiers, systems, locations etc.
The opinions you read on audio forums about the sound quality with various caps is mostly sillyness, particularly when someone is comparing 29 year old caps with new ones of 4 times the value, as I read recently. Unfortunately, some amateurs, even those with strong opinions, still don't have a clue about what they are doing or talking about when they make comparisons with hours, days or even years between making their A-B assessments and often with entirely different amplifiers, systems, locations etc.
Sugden during 1990s used only Rubycon cap, light blue CEW, maybe one or two of other series. This serie seems to be an Aluminium one. So when you speak about spec, the capacitor's material is it a part of it? Or spec is only numbering: temperature, life....? There is an aluminum sound? (Yes, the question is a little bit silly.) If yes you can't change from a material to another without sound changes. On point scientific point of view, spec and data is the only way. But a chemist can analyze a wine but only an oenologist can say is a good or a very good wine. Also, it is why aircrafts are tested in a wind tunnel even after strong mathematic modelization.
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