4.7uf BG N in T-amp or Amp3

t.

Member
2003-05-26 1:35 am
notts
Has anybody tried 4.7uf BG N caps for the T-amp or Amp3 input coupling?

I want to upgrade the input coupling in my Amp3 but not sure what to order, Auricaps have had good reviews when used with T-amps but they are hard to source in the UK
Any recommended types to try would be much appreciated
I have a couple of spare 2.2uf standard M-cap and a couple of LCR MKP's.
I don't fancy fitting and removing the caps because the pcb track is fragile

Cheers!
 
Caps

If you do use the BG caps and they are polarized the + lead must go to the chip. If you are planing to connect directly to input RCA jacks put a 100k metal film res across the jack so the cap will have a path to charge as well as suppling a DC load to the source.
Roger
 
Cap question

t. said:
Thanks Roger:)
I'm hoping to get the Amp3 inside a small Hammond case soon, the only hold up is just deciding which caps to use

Leo


Leo,
I am against any kind of electrolytic in the signal path including BG's finest. I also think they are ripping people off with their high prices. Aside from that I have never actually done an A/B like what you are proposing. Please try both. This could be an interesting comparison. Please post your results.
Roger
 

t.

Member
2003-05-26 1:35 am
notts
Ok matey;)
To be honest the only elecytrolytic I currently use for coupling is in my diy dac and thats a 4.7uf BG N, the ones in my tube amp etc are all films.
I wasn't sure if its advisable to use to many BG N's in the signal path
I normally like Multicap RTX, I have a couple spare but they are only 1uf, it seems 2.2uf is the recommended value.

The pair of 680uf BG NX I'm using on the Amp3's main board for the decoupling are sounding excellent though, certainly better than Panasonic FC,Nichicon muse etc I've tried
 
Caps

Leo,
Electrolytics like having a voltage across them as the +/- fields exert a great deal of force to hold things together and a small ripple won’t disturb them much. If you do use one as a coupling cap and have no bias voltage the distortion can be quite high even with a light load.
As for the 1 uf value for the coupling cap, you probably won’t hear the difference unless you are using it for a bass amp.
Roger