Hello Folks,
I want to recap an old classic integrated amp (HiFi 50) to bring it back to his original performance. In the signal path there are standard polarized Elkos which I want to replace with bipolar Elkos (Nichicon Muse ES).
My question is does it make sense to replace also the Caps in the Feedback Line (C9 100uF/16V) with the bipolar type?
Thanks and Best Regards, Uwe
I want to recap an old classic integrated amp (HiFi 50) to bring it back to his original performance. In the signal path there are standard polarized Elkos which I want to replace with bipolar Elkos (Nichicon Muse ES).
My question is does it make sense to replace also the Caps in the Feedback Line (C9 100uF/16V) with the bipolar type?
Thanks and Best Regards, Uwe
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If the voltages to GND at both nodes of this cap have the same value, a BP version is useful. Otherwise a polarized version is clearly better.
Independent of this - I would replace all 10V versions of electrolytic capacitors by 50V or 63V, even in cases, when only 1 or 2 volts are present.
Independent of this - I would replace all 10V versions of electrolytic capacitors by 50V or 63V, even in cases, when only 1 or 2 volts are present.
Thanks for your reply. Got the point that both can be used but a polarized is prefered if there is an DC offset. Why he beat the BP type? This is what I have available:
4,7uF/50V Panasonic FC
10uF/50V Panasonic FC
100uF/16V Panasonic FC
4,7uF/25V Nichicon Muse UES BP
10uF/25V Nichicon Muse UES BP
100uF/16V Nichicon Muse UES BP
So if you are talking about the 10V version you mean the 100uF/10V type. What is the reason to use >50V types?
Thanks, Uwe
4,7uF/50V Panasonic FC
10uF/50V Panasonic FC
100uF/16V Panasonic FC
4,7uF/25V Nichicon Muse UES BP
10uF/25V Nichicon Muse UES BP
100uF/16V Nichicon Muse UES BP
So if you are talking about the 10V version you mean the 100uF/10V type. What is the reason to use >50V types?
Thanks, Uwe
better reliability, lower ESR, better sound quality, longer lifetime. 50V, 63V and 100V provides according the datasheets best ESR values in most cases.
Low voltage electrolytics are still bad quality standard. This information give me Mr. Jens Both by phone (BC /Philips components) 12 years ago - go to
https://web.archive.org/web/20090218222942/http://www.elcap.de/index2.html
BP electrolytics actually internal two polarized cap in serial connection back to back - go to
https://electronics.stackexchange.c...lytic-capacitors-be-made-into-a-bipolar/69716
As far as I know, most of them just have two formed foils (rather than an antiseries connection of two complete capacitors) and distort less than polar electrolytics, no matter whether there is a DC voltage across them. At least that's what I remember from Cyril Bateman's series about capacitor distortion.
You can find the articles here: https://linearaudio.nl/cyril-batemans-capacitor-sound-articles
You can find the articles here: https://linearaudio.nl/cyril-batemans-capacitor-sound-articles
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Beat me to it…
My go to feedback cap is the Nichicon ES, until something else knocks it off it’s pedestal.
I wanted to try some of the Kaisei but it hasn’t been convenient to make that purchase just to experiment.
My go to feedback cap is the Nichicon ES, until something else knocks it off it’s pedestal.
I wanted to try some of the Kaisei but it hasn’t been convenient to make that purchase just to experiment.
Im confused, according to the Panasonic FC data sheet the Impedance rise with the voltage rating und fall with diameter.
https://www.mouser.de/datasheet/2/315/ABA0000C1209-1289053.pdf
https://www.mouser.de/datasheet/2/315/ABA0000C1209-1289053.pdf
C9 has 10V at one end and 0.05V at the other end. That's more than enough to keep it strongly biased.
Well, OK, if that is all you have, and a re-cap is urgent.
check out
https://www.diyaudio.com/community/...onpolar-bi-polar-bipolar-applications.310034/and post #8 under
https://www.diyaudio.com/community/threads/bipolar-electrolytics-vs-back-to-back-standard.336838/so as this thread:
https://www.diyaudio.com/community/threads/bipolar-capacitor.223061/and this URLs:
http://www.collinsaudio.com/Prosound_Workshop/Capacitor-Sound.pdfhttps://www.dadaelectronics.eu/uplo...ctronics-papers/Capacitor-Sound-C-Bateman.pdfhttps://www.audiosciencereview.com/...cyril-batemans-capacitor-sound-articles.2534/
Correct me if I‘m wrong but all the electrolytics in the application on post #1 are DC biased. Thatswhy (I guess) polarized caps are used by default. If I would replace them all with the polarized FCs it will work fine, check.
But I want to improve the sound quality (THD, clarity?) so the idea was to replace the electrolytics in the signal path with bipolar types which are specially made for audio application (choiced the Muse ES).
My question still is:
1. Can the bipolar type handle the DC bias and make it sense (wrt to improving the sound quality) to replace the polarized type with the Muse ES
2. If 1. is answered with Yes, make it further sense to replace also the Feedback line cap with the Muse ES?
Thanks, Uwe
But I want to improve the sound quality (THD, clarity?) so the idea was to replace the electrolytics in the signal path with bipolar types which are specially made for audio application (choiced the Muse ES).
My question still is:
1. Can the bipolar type handle the DC bias and make it sense (wrt to improving the sound quality) to replace the polarized type with the Muse ES
2. If 1. is answered with Yes, make it further sense to replace also the Feedback line cap with the Muse ES?
Thanks, Uwe
It will work and it will reduce capacitor distortion, but capacitor distortion will probably be very small compared to the distortion from the transistor circuits anyway. That applies to the capacitor in the feedback network as well as to the other AC coupling caps.
Hello Marcel,
thanks for the clear statement. Could you or somebody else explain me what R8 and C7+C38 on the input stage is doing? Is this also kind of a feedback loop which is only applicable for DC (means not affecting the AC signal) since the caps are parallel to the emitter resistor?
Thanks, Uwe