MIxed results using Obbligato Gold Premium Film Caps

[arupg]

I substituted C2 = 0.33 uF and C3 = 1 uF (Marked in RED in the schematic below) in an QUAD Power amp's Input LPF stage using much recommended Obbligato Gold Premium 630V Film caps. The stock caps in the QUAD were standard metalized stacked films of the same values.

The obbligatos' have not been bypassed at all - BUT just left on their own to function. Its now well past 60-70 hrs use and I find the results as under-mentioned:

(1) The Tone is quite robust with "very analog & roundish fullness" but its quite dry. Easily noticeable on Piano, strings, Sax etc. Lacks extension.

(2) Earlier, there used be a spacious airyness in the tone though not as thick sounding as with the Obbligatos (esp. noticeable in the midbass region) but this spaciousness effect has totally disappeared - making the overall presentation rather very Flat and 2-Dimensional. The reverberation is all gone.

After-thoughts

Squeezing the large, heavy & bulky Obbligatos in place of standard films was quite a challenge & a hell-of-a-task but now the net results ain't bringing any smiles - meaning do I need to revert back to the way things were earlier? i.e. removal of the "mighty Obbligatos" ?

Your suggestions will be most appreciated.

Thanks in advance . . .

[Lee Knatta]

Audio Vodoo caps

What a waste of time.

Ever wondered why the manufacturer neither provides information about dielectric used nor capacitance tolerance or dissipation factor? Just put a gold sticker on it and the audiophools will buy it. Old story.

[effebi]

Bah, at a 1st look, 330 nF looks a little small on the input.
You may give it a try with a of-the-shelf Polyester or polipropilene say 1 to 4.7 uF, 100V rated is more than enough. I mean , common brands Wima, Evox-Rifa, Vishay. The experiment won't cost you more than a couple of Euro and you might be surprised.
effebi

[arupg]

@ effebi
The Stock 0.33 & 1.0 uF were the regular Wima/Vishay/Evox-Rifa types and the results were quite good. I wanted it even better so tried genuine Film like the much touted Obbligato Gold Premium. BUT - after the work, it is not sounding good.

Maybe someone suggested that the Obbligato Caps are very tightly wound with thick film, so will need long break-in. Logically thinking, maybe this could be true.

The 0.33 & 1.0uF values are not the problem, the Obbligato Cap is the problem right now!

[arupg]

hmm - seems no one wants to answer here.
Guess will keep the break-in on "strong mode" and hope for the best.
Ain't giving up on those Obbigatos so fast . . .
They gotta sound good - sooner or later

[Lukas87]

C3 can not have any measureable nor audible effect at all. it's in the feedback stage of DC-servo...
C2 can benefit from bigger value (or utlimately from change to PP type - I guess it is MKS or something alike).
C1 should bother you too - put there some decent ordinary film cap if it's ceramic.

just put there something from Vishay/Rifa/Wima and don't care about it anymore - in your search for "better sound" you will probably need a better amp caps really don't do the magic.

[WuYit]

Hi,
what materials are used in that thick film capacitor? My choice would be teflon, polystyrene or non-metalized polypropylene.

[Lee Knatta]

Originally Posted by arupg

hmm - seems no one wants to answer here.
Guess will keep the break-in on "strong mode" and hope for the best.
Ain't giving up on those Obbigatos so fast . . .
They gotta sound good - sooner or later

They have to have sound good because they are "mighty Obligatos"??? Come on, are you serious? I think you are a victim of aggressive marketing common for products targeted at audiophools.

Do you know what kind of dielectric is used inside the cap? (Do you know what a dielectric is at all?) Obviously the manufacturer doesn't tell and hides other important information about the product as well. Maybe for good reason. Maybe the caps don't spec well despite being hand rolled by blonde virgins in a clear full moon night. Don't let you fool by the golden sticker and what the manufacturer claims about the sonics.

Better give up here, use an ordinary film cap with standard metallised polypropylene dielectric, increase the value of C2 like effebi suggested, follow the advice of Lukas87 who got it absolutely right as well and buy some overly expensive audio voodoo cables instead or maybe a magic stone to put on top of you speakers to improve the sound or any other audiophool product that makes you happy.

[singa]

Hi, Try a tube preamp Like a diy Kondo Audionote M7 with 12AY7 tubes and
6X4 tube rectifier with good caps.

Don't let names bother you ,who has not ridden a bicycle and not fallen
off? Regards.