Polystyrene and polycarbonate films are probably not going away, but capacitor grade polycarbonate films are an iffy proposition right now. Having dealt with several vendors at work, I cannot get a consistent story, with some insisting that the main veondor(s?) of capacitor-grade polycarbonate films are dropping it due to low margins, while others insisting that they have other sources. Hence, the situation is "iffy."
I don't know what the situation for polystyrene is, since I have been looking at power capacitors mostly.
John
I don't know what the situation for polystyrene is, since I have been looking at power capacitors mostly.
John
Hello Halo,
You won' find the Bateman articles on the web.
The current (November) issue of Electronics World (formerly
Wireless World) contains part 4 of his 6-part series.
EW is a British publication, though I pick mine up at
my local Barnes & Noble.
JohnG and jackinnj, you can think whatever you want
but that doesn't change the facts. The company that
made polystyrene films for capacitors (a German company,
I think) stopped several years ago. Apparently
the same is now happening to polycarbonate films.
To quote Bateman:
With the production of Bayer Makrofol Polycarbonate
film having ceased, metallised (sic) Polycarbonate
capacitors may disappear.
I have also heard the same from other sources.
Fortunately, I've never been that excited about
Polycarbonate. And Polystyrene is really nice but
too expensive/large/touchy/unreliable for me.
You won' find the Bateman articles on the web.
The current (November) issue of Electronics World (formerly
Wireless World) contains part 4 of his 6-part series.
EW is a British publication, though I pick mine up at
my local Barnes & Noble.
JohnG and jackinnj, you can think whatever you want
but that doesn't change the facts. The company that
made polystyrene films for capacitors (a German company,
I think) stopped several years ago. Apparently
the same is now happening to polycarbonate films.
To quote Bateman:
With the production of Bayer Makrofol Polycarbonate
film having ceased, metallised (sic) Polycarbonate
capacitors may disappear.
I have also heard the same from other sources.
Fortunately, I've never been that excited about
Polycarbonate. And Polystyrene is really nice but
too expensive/large/touchy/unreliable for me.
Goodbye Styrofoam Capacitors...
"And Polystyrene is really nice but
too expensive/large/touchy/unreliable for me."
I have used 1.1 uF polystyrenes as tweeter cap, and found that they need bypassing with lower values, and give an unsettling quality to highs - a bit like when white styrofoam squeaks.
Polypropylene with ceramic bypass sounds better to my ear.
Eric.
"And Polystyrene is really nice but
too expensive/large/touchy/unreliable for me."
I have used 1.1 uF polystyrenes as tweeter cap, and found that they need bypassing with lower values, and give an unsettling quality to highs - a bit like when white styrofoam squeaks.
Polypropylene with ceramic bypass sounds better to my ear.
Eric.
I have just read the Dec issue of Electronics World.
In the penultimate article of the series the author writes that a cd-rom full of capacitor measurement data will be produced and will be available sometime after the last article has been printed (Jan 2003?).
So, after this has come out, none of us have any excuse anymore in using badly distorting caps in our designs, right?
regards,
Halcyon
In the penultimate article of the series the author writes that a cd-rom full of capacitor measurement data will be produced and will be available sometime after the last article has been printed (Jan 2003?).
So, after this has come out, none of us have any excuse anymore in using badly distorting caps in our designs, right?
regards,
Halcyon
"Yer not takin' the Kingswood!"
That's mine 3 from the bottom, the brown one. The pic is just over 10 years old now, took the photo just when I got it. Done 473,000 km. http://members2.easyspace.com/hotholdens/model/h/hj_1974-76.html
This car is an Aussie icon, like mom, apple pie and Chevrolets are to the Yanks. Even a TV show was named after it.
KINGSWOOD COUNTRY
7 Network-RS Productions / 89x30m-e / 1979-84
Creators/Producers: Tony Sattler, Gary Reilly / Music: Mike Perjanik
Sitcom. Ted Bullpit is an Alf Garnett like bigot who loves his Holden Kingswood more than his wife. Based on a character first seen in "The NakedVicar Show".
With:- ROSS HIGGINS / JUDI FARR (1979-82) / LES MARINOS / LAUREL McGOWEN / PETER FISHER / SHEILA KENNELLY (1982-84)
***********************
Culture? We've got culture comin' out our ****!
That's mine 3 from the bottom, the brown one. The pic is just over 10 years old now, took the photo just when I got it. Done 473,000 km. http://members2.easyspace.com/hotholdens/model/h/hj_1974-76.html
This car is an Aussie icon, like mom, apple pie and Chevrolets are to the Yanks. Even a TV show was named after it.
KINGSWOOD COUNTRY
7 Network-RS Productions / 89x30m-e / 1979-84
Creators/Producers: Tony Sattler, Gary Reilly / Music: Mike Perjanik
Sitcom. Ted Bullpit is an Alf Garnett like bigot who loves his Holden Kingswood more than his wife. Based on a character first seen in "The NakedVicar Show".
With:- ROSS HIGGINS / JUDI FARR (1979-82) / LES MARINOS / LAUREL McGOWEN / PETER FISHER / SHEILA KENNELLY (1982-84)
***********************
Culture? We've got culture comin' out our ****!
Flipping this thread back where it started.
The final article in C. Bateman's series is out in Jan/2003 issue of 'Electronics World' (UK).
It contains more interesting information and a cd or floppy one car order with the PCB drawing, capacitor measurement data and additional info.
I have posted the contact information in another message:
http://www.diyaudio.com/forums/showthread.php?s=&postid=96875
regards,
Halcyon
The final article in C. Bateman's series is out in Jan/2003 issue of 'Electronics World' (UK).
It contains more interesting information and a cd or floppy one car order with the PCB drawing, capacitor measurement data and additional info.
I have posted the contact information in another message:
http://www.diyaudio.com/forums/showthread.php?s=&postid=96875
regards,
Halcyon
fmak,
that's a good point. Would you venture a guess or have some references as to what other measurable characteristics could be a partial indication to the sound quality of caps?
I think the C.Bateman series is very good at least in terms of SNR, THD and IMD measurements, but like you said, probably not the last word on 'transparency' in audio use.
regards,
Halcyon
that's a good point. Would you venture a guess or have some references as to what other measurable characteristics could be a partial indication to the sound quality of caps?
I think the C.Bateman series is very good at least in terms of SNR, THD and IMD measurements, but like you said, probably not the last word on 'transparency' in audio use.
regards,
Halcyon
Tan delta is in my experience important; I actually choose units with the lowest ones in upgrading. This can vary by a factor of three in a batch of Hi Q electrolytics. The audiophiles types do sound better, even if they have the same order of magnitude of distortion, ie Black Gate FKs and Ns.