Hi Guys.
To be frank just go for any name branded electrolytic with a rating of 35V or more. Look for a LOW ESR type, with a 105 deg. C rating from a known manufacturer and save your money. The QUAD uses offset power rails of +8.6V / -9.4V to power the OpAmps so the CAPS will always have a DC voltage across them and there is no source of temperature stress inside the 34 preamp. If you get a 35V Rated caps (and 50V for the PSU Caps) they will be operating well inside their limits and they will last well past their rated life by a good many decades.
Call me cloth eared but I am yet to hear any difference between known branded capacitors that have been appropriately selected according to the application and are operating within their limits. Modern Electrolytic technology has come a long way since the 70’s and early 80’s. Modern capacitors, with the exception of the cheap Chinese copies, are capable of respectable performance. Look inside allot of modern upmarket Hifi gear and you will see many parts with names from component manufacturers based in the far east.
You can quite often do damage to an aging PCB by reheating solder pads just to experiment with different caps that can easily outweigh any real tangible benefit that might be gained.
Happy Listening
LPSpinner.
Thank you very much, LPSpinner and also to all the others with your very valuable contributions. Do you know that now I feel much better with my decision, because I will order Panasonic e-caps. In addition, an observation about these caps in all kinds of forums posts around the world. Pretty much everyone shows their satisfaction and...voila, that's mostly all there is to say. In contrast, there is so much blather about Silmic2 or Muse or whatever other "audiophile" caps as if it were a red wine forum, talking about vintages, wineries, soil, grapes, tannin content, etc. I am so glad to have found a reliable and credible place here. Well...I started the thread by saying that I am dissatisfied with Simic2 in my specific application. It is perhaps like the fairy tale "the emperor's new clothes". If I had started a thread praising Silmic2 then most likely the "wine connoisseurs" would have spoken up.
One question, in the link is a Panasonic FR with 35V. All FC types and other FR with 50V are indefinitely out of stock at Mouser (where I always order, because from 50€ without shipping costs).
The Panasonic FR look quite decent according to the data sheet, low ESR, long life, 105C etc. I think the FR series is just newer? Is there anything against it?
https://www.mouser.de/c/passive-components/capacitors/aluminum-electrolytic-capacitors/aluminum-electrolytic-capacitors-radial-leaded/?capacitance=100 uF&m=Panasonic&product=Low ESR Electrolytic Capacitors&series=FR&termination style=Radial&voltage rating dc=35 VDC
You can even find comments on the net where a low ESR on e_caps is equated with a shrill sound. How do people get that idea? I personally know only one case where a higher ESR is beneficial, and that is in the xover of my very old 1977 Klipsch Lascala (softer "Q", intended over all impedance of the network, confirmed by Roy Delgado, chief developer).
Meanwhile I have seen in the net that Silmic2 in particular have a poor ESR that may contribute to the congested sound. This data I have found in a German article:
- Elna Silmic II: (D)=0,0532 / (Phasenwinkel)=-86,9° / (ESR)=1,917 Ohm / Q=18,77
- Nichicon UKZ: (D)=0,0287 / (Phasenwinkel)=-88,3° / (ESR)=0,971 Ohm /Q=34,83
- Nichicon FG: (D)=0,0574 / (Phasenwinkel)=-86,7° / (ESR)=2,214 Ohm / Q=17,41
- Panasonic FM: (D)=0,0395 / (Phasenwinkel)=-87,9° / (ESR)=1,409 Ohm / Q=25,23
Since there are people with "reasonable approach" in this thread, another question beyond the Quad 34. I had ordered for my two Quad 306 the PSU caps below in the link. I have not been "audiophile" oriented but I went by lifetime and temperature. Did I do something wrong or is everything ok? Sonically, everything is really good.
Thanks a lot for reading.
https://www.mouser.de/ProductDetail/KEMET/ALC80A562CC063?qs=T94vaHKWudSbqp8mWLAllw==&countrycode=DE¤cycode=EUR