Caiman passive output mod revealed

[AndrewR]

There is a 2.5V DC component on the output of the DAC chip. So without the cap you are going to short the DAC chip to ground.

Doh [to me]!

I've been getting carried away with coupling transformers using my Passive Caimanised 7520 with an interstage valve amp I designed and built a little while ago (no caps in signal path). More on that later (will post on the DIY board here).



Andrew

[Alex_UK]

Silly question alert: Got my Caps from Tirna today - the legs are not the same length, so presume I just trim them the same length? (yet to open the Caiman, best unload the car and help with the unpacking first!)

[EDIT] All sorted, and even better, sound is coming out of both channels so I haven't cocked it up! It was dead easy, a 5 minute job. If anyone wants a pair of the Tirna-supplied Rubycon Bi-polar 47uF caps FOC then PM me, and I'll pop them in the post tomorrow. Leaving it with Sky HD running them in for 4 or 5 hours or so before I have a proper first listen.

[Puffin]

Silly question alert: Got my Caps from Tirna today - the legs are not the same length, so presume I just trim them the same length? (yet to open the Caiman)

Are they polarised or non-polar. If the former the longest leg is positive, you can cut to desired length. If the latter the same applies, but you do not have to observe polarity.

OK, I am going in!!...........Wear bicycle clips. brown slippers are a bit smelly!

[Alex_UK]

Thanks Puffin - see edited post!

[Alex_UK]

Rubycon caps now spoken for.

[Alex_UK]

All sorted, and even better, sound is coming out of both channels so I haven't cocked it up! <snip> Leaving it with Sky HD running them in for 4 or 5 hours or so before I have a proper first listen.

Quick first impressions: The soundstage has opened a little, (wider) and the midrange seems emphasised compared to the standard Caiman. Bass is lighter, I feel - but it does appear that the sound is clearer. I wan't my bass back, though! No noticeable problem with female vocals as some have expressed. I think this mod will make the Caiman more critical of bad recordings, based on a couple of tracks that sound a bit ropey as standard, bloody awful now!

Some more burning in to do before drawing any conclusions* (never believed in it making a big difference before, until I bought the Caiman...) One thing's for sure, though - if it takes a fair few hours to achieve optimum sound then I doubt I will be trying many more (any more) caps, as life is too short not to be just listening to the music!

(*Cautiously optimistic, though, based on the sounds of the piano and glockenspiel in addition to her vocals on Charlotte Gainsbourg's 5:55)

[Stratmangler]

Quick first impressions: The soundstage has opened a little, (wider) and the midrange seems emphasised compared to the standard Caiman. Bass is lighter, I feel - but it does appear that the sound is clearer. I wan't my bass back, though! No noticeable problem with female vocals as some have expressed. I think this mod will make the Caiman more critical of bad recordings, based on a couple of tracks that sound a bit ropey as standard, bloody awful now!

Some more burning in to do before drawing any conclusions* (never believed in it making a big difference before, until I bought the Caiman...) One thing's for sure, though - if it takes a fair few hours to achieve optimum sound then I doubt I will be trying many more (any more) caps, as life is too short not to be just listening to the music!

(*Cautiously optimistic, though, based on the sounds of the piano and glockenspiel in addition to her vocals on Charlotte Gainsbourg's 5:55)

The caps take a while to settle in.

My son decided tonight that he'd watch the Wallace & Gromit movies (A Grand Day Out/The Wrong Trousers/A Close Shave), and I was gobsmacked at the amount of low end grunt coming off the brass band with the W&G theme tune - that and the clarity of the dialogue/sound effects.

I've got some Silmics in there ATM, and I like them a lot.
Nichicon Muse bi-polars were the last in, and I liked those too.

[MartinT]

I wan't my bass back, though!

It'll come back, don't worry

[Ali Tait]

Alex,if you can find out the input impedance of your amp,you may be able to try a film cap in there for a reasonable price,which should be better than any electrolytic.

[Alex_UK]

Thanks Martin - it has! Oooh my, needed double-figure hours, but the bass is back and the wholesound seems to be getting better. Biggest difference so far is definitely the wider soundstage and the word Chris (Stratmangler) used - "Clarity" is very appropriate. Noticed some splashy cymbals on a couple of tracks, which is the only negative I've heard so far, though hopefully that will improve. Not much time to listen today I suspect, but looking forward to trying some well known CDs later tonight.