Bottlehead Forum

Bottlehead Kits => Crack => Topic started by: thomas27 on June 10, 2014, 05:48:22 AM

Title: Obbligato caps / capacitance
Post by: thomas27 on June 10, 2014, 05:48:22 AM

I'm thinking of replacing the crack output caps with film cap. Not expecting a massive difference in sound quality but I like the idea of keeping them in for the next 10-20+ years and not worry about them at all.

For about $100 I could get:
- 2x 100uF Obbligato Film Oil 400V
- 2x 47uF Obbligato Gold Premium 250V

With Senn HD650, cut-off frequencies would be 6Hz and 12.5Hz respectively (I would not use other headphones). 12.5Hz is perhaps slightly borderline (the v-cap website mentions potential "phase anomalies" close to cut-off frequency) but would that be compensated by the fact that the gold premium is slightly better sounding and that there would be less material in the signal path + presumably thinner dielectric?

I have read some very interesting stuff on the topic but I would be interested in hearing about your experience:
http://bottlehead.com/smf/index.php/topic,3736.msg33681.html#msg33681
http://bottlehead.com/smf/index.php/topic,526.60.html
http://www.v-cap.com/coupling-capacitor-calculator.php

Thanks a lot
Thomas

Title: Re: Obbligato caps / capacitance
Post by: Paul Birkeland on June 10, 2014, 05:53:00 AM

A 100uF @ 400V film cap is going to be huge and pretty difficult to fit inside the amp.

You probably won't be bothered by the low frequency issues with the 47uF caps. 

Title: Re: Obbligato caps / capacitance
Post by: thomas27 on June 10, 2014, 07:20:09 AM

Thanks PB

The 100uF caps are indeed very large (2.6" D x 5.3" L) but they would still fit.

Would be interested in any feedback from Bottleheads!

Title: Re: Obbligato caps / capacitance
Post by: JamieMcC on June 10, 2014, 09:58:34 AM

I Think you will struggle to get those big Obbligato Film Oils in also, lengthways wont be so much of a problem as width wise. The speedball boards will be the limiting factor.

Obbligato also do a 100uf PSU film cap that is a little smaller seem to recall a crack with one fitted but not sure.

 

Title: Re: Obbligato caps / capacitance
Post by: thomas27 on June 10, 2014, 10:15:27 AM

Sorry, should have mentioned that I'm using a Blumenstein base which has more real estate :)

Title: Re: Obbligato caps / capacitance
Post by: saildoctor on June 10, 2014, 10:18:30 AM

I have some of those Obbligato Gold Premiums in my rig (not a headphone amp) and think they sound pretty nice.

Title: Re: Obbligato caps / capacitance
Post by: JamieMcC on June 10, 2014, 10:30:44 AM

I had four Valab 47uf Fastpower's fitted in my Crack for a while there didn't seem to be any difference between running a pair of 47uf's  to a single 100uf each side. I believe from my  time spent perusing the bh forum that this would also half the ESR vs a single 100uf which is said to be good thing but as a newbi myself I have most probably got that wrong?

Title: Re: Obbligato caps / capacitance
Post by: 2wo on June 10, 2014, 04:35:52 PM

I have been very happy with Obbligatos. I would go for the gold 47's...John