Caiman passive output mod revealed

[Reid Malenfant]

If I had accepted other people's theory, I would never have tried some of the mods that have resulted in some great results.

Oh i agree with that I'm sure most audio engineers would laugh if i said i could make a 190W RMS (4ohm) single ended class A power amp with a quiescent dissipation of about 150W & 13Amp quiescent current

You just need to think out of the box

[Ali Tait]

Eggsackerly!

[apmusson]

DSCF0902.jpg

Here is my Caiman.... With those lovely yellow ebay caps. I have managed to get the case to close. One Cap by the USB input, the other in the same position but nearer the front of the Caiman. You have to hook the caps under the case indents, but they don't get crushed and they sound great.

I am going to get a couple of 0.1uf caps just to see the difference they make, but for now I'm going to do some serious listening with this lovely setup.

Ade

[HighFidelityGuy]

DSCF0902.jpg

Here is my Caiman.... With those lovely yellow ebay caps. I have managed to get the case to close. One Cap by the USB input, the other in the same position but nearer the front of the Caiman. You have to hook the caps under the case indents, but they don't get crushed and they sound great.

I am going to get a couple of 0.1uf caps just to see the difference they make, but for now I'm going to do some serious listening with this lovely setup.

Ade

Nicely done Ade. I picked up a pair of those caps too and I've been running them for the past week. So far they seem very good good. Nice and smooth but detailed with good sound stage. They're probably about the best I've tried so far but I've tried that many I'm starting to struggle to remember what some sounded like. I think I'm going to have to go back through them all now that they're all run in.

I also fancy trying adding extra bypass caps to mix and match the sound. Is there any reason I shouldn't try running a pair of high value (up to 47uF) caps in parallel with the Italian 10uF ones? I'm thinking this could allow me to get the best characteristics from a couple of different types of caps. Or is that just madness?

[HighFidelityGuy]

Well I decided to try strapping a couple of different film caps together to see what difference it made to the sound. I bypassed a pair of Mundorf RXF 22uF with the Italian 10uF caps off ebay. I ended up with a massive bulk sticking out the the top of the poor little Caiman but it works (with the aid of some insulating tape for stability). I'll try and post a picture soon, it looks quite comical.

Anyway, at first I was a bit dissapointed with the results as I was hearing some harshness in the trebble but that died down after a day of running in. I'm now quite happy with the overall sound. I do seem to have got some traits from both. The Italians have provided the smoothness and the Mundorfs have added some air and lightness and some extra width to the stereo image. I also seem to be getting deeper bass now, probably due to the Mundorf's adding an extra 22uF. So my bass roll off frequency will be a fair bit lower than before.

So overall the experiment has been successful but I feel it could be improved upon. I've ordered some 0.05uF silver mica and 0.1uF teflon caps from ebay to try as bypass caps. They may take a while to come from Moscow though.

[apmusson]

Dave

I'd love to see the pictures... Somewhere in this capacitive collection there is audio perfection. I love the 10uf ebay caps and am going to keep those as my base capacitance and try a few different values as bypass caps too.

Ade

Well I decided to try strapping a couple of different film caps together to see what difference it made to the sound. I bypassed a pair of Mundorf RXF 22uF with the Italian 10uF caps off ebay. I ended up with a massive bulk sticking out the the top of the poor little Caiman but it works (with the aid of some insulating tape for stability). I'll try and post a picture soon, it looks quite comical.

Anyway, at first I was a bit dissapointed with the results as I was hearing some harshness in the trebble but that died down after a day of running in. I'm now quite happy with the overall sound. I do seem to have got some traits from both. The Italians have provided the smoothness and the Mundorfs have added some air and lightness and some extra width to the stereo image. I also seem to be getting deeper bass now, probably due to the Mundorf's adding an extra 22uF. So my bass roll off frequency will be a fair bit lower than before.

So overall the experiment has been successful but I feel it could be improved upon. I've ordered some 0.05uF silver mica and 0.1uF teflon caps from ebay to try as bypass caps. They may take a while to come from Moscow though.

[HighFidelityGuy]

Dave

I'd love to see the pictures... Somewhere in this capacitive collection there is audio perfection. I love the 10uf ebay caps and am going to keep those as my base capacitance and try a few different values as bypass caps too.

Ade

As promised :



They protrude by about 3 inches at the moment. I could get them to fit better but it was just a quick experiment, so I'm not bothered about neatness.

I really want to try some higher end film caps but my current setup requires high value caps, so that means spending lots. I've heard the standard Mundorf Supremes are good value for money so I'm going to try the highest value of those I can get next month. I should have my silver mica and teflon bypass caps to play with by then too, so I'm looking forward to further experimentation.

I think one of the tricky things is going to be that what works for one person might not work for another due to different setups being used. So we're only going to be able to roughly guide each other based on what changes different caps make to the sound. Hopefully we'll all stumble across our own favourite caps soon.

[Gazjam]

Got around last night to fitting 0.1uF bypass caps onto the yellow ebay film cap?
Stan B had mentioned it as a good thing to do...in his usual understated way of course...

flippin 'eck!


I noticed a difference right away, the mid and treble had "changed" somehow...it was a different kind of presentation?

More "texture" is how I would try to describe it?
Theres detail coming through I hadn't heard..really subtle stuff, for instance the WAY a guitar note is being strummed...sustain, harmonics, amplifier noise, all of that.

At first I thought I had lost a bit of bass depth - and I had - and there was less "impact", particulalrly with the big classical stuff.
But the detail was all there, much more so than before. Room ambience, mike noises...very distracting.

I left the Dac playing the telly overnight, I had noticed cap burn in before and whilst I hadnt expected anything (dont know why) with the wee 0.1uF caps I thought I'd give it a go anyway.

This morning the bass was back, big time.
A lot tighter and with more depth..the kind of bass you feel in your trouserlegs!

If you have done the passive mod..get some film caps.
If you have film caps...fit a bypass cap.

..dont ask why, just do it

[Gazjam]

As promised :



They protrude by about 3 inches at the moment. I could get them to fit better but it was just a quick experiment, so I'm not bothered about neatness.

I really want to try some higher end film caps but my current setup requires high value caps, so that means spending lots. I've heard the standard Mundorf Supremes are good value for money so I'm going to try the highest value of those I can get next month. I should have my silver mica and teflon bypass caps to play with by then too, so I'm looking forward to further experimentation.

I think one of the tricky things is going to be that what works for one person might not work for another due to different setups being used. So we're only going to be able to roughly guide each other based on what changes different caps make to the sound. Hopefully we'll all stumble across our own favourite caps soon.

Dave,
I'm in the same boat as you, looking at better film caps.
I started a thread over on the 'Wam, some good links/responses from the guys over there.

http://www.hifiwigwam.com/showthread...LY-priced-type

[StanleyB]

Got around last night to fitting 0.1uF bypass caps onto the yellow ebay film cap?
Stan B had mentioned it as a good thing to do...in his usual understated way of course...

flippin 'eck!


I noticed a difference right away, the mid and treble had "changed" somehow...it was a different kind of presentation?

More "texture" is how I would try to describe it?
Theres detail coming through I hadn't heard..really subtle stuff, for instance the WAY a guitar note is being strummed...sustain, harmonics, amplifier noise, all of that.

Some said it would never work. But I am accustomed to the theory getting in the way of tangible evidence.