[sleepy dan]

The decoupling caps I'm reffering to are the two yellow marked ones on the far left of the photo. The green caps are coupling caps ... they couple one part of the circuit to the next.

 

[ablaze]

thanks dan. obviously, I'm not too technically inclined

 

[uzziah]

ok. the green "coupling" caps i have "bridged" (solder bridged the legs together on bottom of card) to bypass them. is this the best option?

 

[uzziah]

so blackgates are the main thought, eh? what about cerafines or others? i certainly must find "what i like" but what i'd like at first is to have something to start from. in truth i'm rather skiddish about spending the $ on the blackgates. maybe i should just suck it up. but, any other suggestions for me to consider?

also: remove coupling caps or replace? is "remove if you have low offset" the right answer?

 

[uzziah]

Remember to bypass them with a small film cap too.



i don't follow you

 

[sleepy dan]

As for cap type ... pfffffff ... everyone has their favourite. Rubycon ZAs have a good rep and are cheap, though I haven't tried them myself. Otherwise you can't go far wrong with OsCons or Panasonics. Blackgates are good, but I'm not sure they are worth the money.

Larger caps work less well at higher frequencies. The solution in to parallel (bypass) them with smaller caps, typically film caps of around 10 - 100nf. Fast op-amps in particular need a power supply with good high frequency behaviour.

And yep, bridge the coupling caps.

 

[ablaze]

sleepydan,
how high would you suggest we go for the decoupling caps considering the stock ones are only 10uF? 47uF? 100uF? 680uF?

Ian,
which black gate N/NX caps are you referring to exactly that have leads larger than would fit on the board?

 

[lan]

Quote:

Originally Posted by uzziah ok. the green "coupling" caps i have "bridged" (solder bridged the legs together on bottom of card) to bypass them. is this the best option?

No cap here is better than a cap. And if you have these caps in your amp, it's redundant to have them here. But then, since a cap would change the sound, some people would like that option to tweak the sound.

Quote:

Originally Posted by uzziah so blackgates are the main thought, eh? what about cerafines or others? i certainly must find "what i like" but what i'd like at first is to have something to start from. in truth i'm rather skiddish about spending the $ on the blackgates. maybe i should just suck it up. but, any other suggestions for me to consider?

Cerafines are physically too large and I don't know if their leads are also.

Well you're going to have to get something first to acclimated to and them when you go blackgate then you can believe the difference

Try Panasonic FC first. Many people use it, get used to the sound. I'm not a fan of it though but it's good to try.

Quote:

Originally Posted by ablaze Ian, which black gate N/NX caps are you referring to exactly that have leads larger than would fit on the board?

Well I havn't tried them all but FK 16v 100uF is too large. N 50V 47uf is also. But really those are more expensive and not as good as 6.3V NX-hiq. I just know from having them on hand.

 

[ablaze]

Quote:

Originally Posted by lan Well I havn't tried them all but FK 16v 100uF is too large. N 50V 47uf is also. But really those are more expensive and not as good as 6.3V NX-hiq. I just know from having them on hand.

hmm..damn the FK 16v is only a 10mm-diameter cap and it won't fit?

(would it be a fair guess that lead diameter would correspond to cap diameter?)

damn that reaaaallly limits my choices for blackgates now

 

[uzziah]

ablaze, see my similar post in the diy section. diyparadise.com has a very interesting study on caps. oscon's came out on top for low ESR etc. worth a read.

sanyo oscon is my cap of choice right now. shouldnt' cost me more than $15 to populate the right caps, here, with significant upgrades in capacitence.

 

[sleepy dan]

Quote:

Originally Posted by ablaze sleepydan, how high would you suggest we go for the decoupling caps considering the stock ones are only 10uF? 47uF? 100uF? 680uF?

As big as you can fit. Me, I'd try to get 1000uF in there if possible.

 

[uzziah]

http://www4.head-fi.org/forums/showthread.php?t=110891

i've contiinued this thread there, with some interesting tidbits

 

[ablaze]

can somebody give me exact directions to biasing the opamp to Class A? I've got a CRD here. which pin of the opamp do I solder it to, and where the hell does the other end of the CRD go to?

 

[ablaze]

well I'm planning to NX-hiQ all the "yellow" caps in the pic

problem is those 3 "12v" caps marked in the picture (2 on the left, one more in the middle)

I was initially planning to use the NX 1000uF 25v caps, but saw the caps in a local store today, and they're HUGE! (its one thing to see "16x25mm" in words, and another to see the actual 16x25mm cap in person lol) the only way to fit them will be to fit them on the back of the board.

a question:

to borrow iron_dreamer's photo

are those excess lead lengths gonna be detrimental to the sound?

 

[ablaze]

bump for opinions