LA2A question about C5

Jimbo_9er · Oct 1, 2008

I am curious as to whether there is a reason to use such a high voltage cap for C5. Most people I've seen in searching for this question, mention that they use 450, 650, 1000, etc. I am interested in using a 200V polypropylene in this spot. Any problems?

(of course I see the ~100v on CJ's voltage chart and another cathode follower circuit I'm familiar with uses a 150v, but I want to check with those who would know for sure before I order parts.)
Thanks,

Bluzzi · Oct 1, 2008

C5 is directly connected to the output XFR and will most likely influence the sound. I used electrolytic sprague atom (huge) at 450v. The polypropylene is non polarized right?

jim

dripelectronics · Oct 1, 2008

im reading about 115v on the positive side .
with a unit at max volume . (stays the same for zero volume)

200VDC seems like it would be ok ,
it could as bluzi said effect the tone of it .
but youll have to compair for yourself.

given that most parts are rated a bit below their
failing point , and can handle a high surge voltage for brief moments,
you should be ok.

but .... i did have a few 450v caps pop @ 500v
during some power supply tests .
so some times what they say about the rating is true.

all this is in my opinion aka IMHO

giving your self headroom is alway a good idea ,

if your only saving a buck or two , get the 400-500v version

TC 72's mallory 10uf@ 450v caps cost 10$ at allied electronics.
TC 52's mallory 10uf@250v caps cost 9.40$. @ same place.

g.

Jimbo_9er · Oct 1, 2008

Thanks for the replies. Yes it is non polarized, but there is a recommended direction. I am looking at Auricaps. They are my favorite and I use them in the same spot in another CF output. I tried several different types and brands and these simply smoked everything else I tried in my preamps. (didn't try Hovland) Orange drops were really lame in comparison for coupling. No contest. (imho) I used to like them just fine and still use them in some places.
The 200V 10uf is $26, the 450V is $45.

I'm just aiming for high quality, not necessarily an exact clone. I'm building an ~La2a with an Ampex EF86/12AY7 mic preamp circuit which can be switched in between the Ha100x and the T4, all in an Ampex 601 chassis. This is where I am heading anyway. It's part of my continuing exploration of the 601 and its potential. See my site for examples.

Thanks again,

Jimbo_9er · Oct 1, 2008

[quote author="dripelectronics"]im reading about 115v on the positive side .
with a unit at max volume . (stays the same for zero volume)

200VDC seems like it would be ok ,
it could as bluzi said effect the tone of it .
but youll have to compair for yourself.

given that most parts are rated a bit below their
failing point , and can handle a high surge voltage for brief moments,
you should be ok.

but .... i did have a few 450v caps pop @ 500v
during some power supply tests .
so some times what they say about the rating is true.

all this is in my opinion aka IMHO

giving your self headroom is alway a good idea ,

if your only saving a buck or two , get the 400-500v version

TC 72's mallory 10uf@ 450v caps cost 10$ at allied electronics.
TC 52's mallory 10uf@250v caps cost 9.40$. @ same place.

g.[/quote]

Thanks very much for taking that effort. I saw you recommend those caps before and since I order from Allied all the time, I will try them. (They are 40 miles away. It's great to place an order one afternoon and get it the next.)

CJ · Oct 2, 2008

Poly will give you a bit less smeared high end, but usually the LA2 is used for vocals, so not a lot of vocal around 20 K unless your Maria Carey.

Jimbo_9er · Oct 2, 2008

LOL, thanks CJ. I will be using it on sax, maybe flute, t'bone, and who knows, if it sounds good... I think, I hope.

justinheronmusic · Oct 8, 2016

Has anyone compared the differences with a Solen and a Sprague in C5? Would this capacitor choice affect the tone more so than a Carnhill vs Cinemag Transformer?