Coupling Capacitor - Pls Help

[tony Ma]

I have JP200 and just solved the problem that I got (excessive noise and un-balance between the channel)
Now I am thinking to change the capacitor

I am leaning on these capacitor only

Mundorf Supreme Silver oil

Janzten

Auricap

The capacitor that I need is .47uf (Coupling Capacitor) and 1uf and 2uf

Due to the budget, I am thinking to use .47 with Mundorf and remaining using Auricap.

Currently this pre-amp using solen capacitor and I have tungsol reissue
I feel that the sound is that open

Here is my set up
CD - VALAB Nos DAC (I did modify the capacitor) - JP200 - B&K ST-140 and Speaker is DIY from STATEMENT SPEAKERS by Jim Holtz

Here is the schematic
http://analogmetric.com/download/JP2...0Schematic.pdf

Any input pls....

tks

[GloBug]

"Due to the budget, I am thinking to use .47 with Mundorf and remaining using Auricap."

I would go that route if you must. I can't really comment on them and would like to try a few myself.

Keep in mind that the cap upgrade could exceed half the value of your amp.

That's not the end of the world for a hobby by any means, although that money could be put towards a better unit with plain caps.

[ruffrecords]

It does not matter which of those coupling capacitors you use, there will be no discernible difference in the sound.

Cheers

Ian

[Palustris]

If you have a cap on the output of your DAC there is no need for the one on the input of the preamp so eliminate C1a/b. That will save a few bucks. Second, 470nF coupling caps are way oversize. 100nF will give a -3dB point of 3.4 Hz. Forget the 10nF cap as it is unnecessary. That will save more money although I would use the Mundorf silver so you won't save much. The 2uf output caps are critical. I would go with Russian KBG 2uF 200V. That's what I use in the same position on my preamp and in my speaker crossovers.

[tony Ma]

@palustris,
When you want have a good impact, I thought the most important cap is input cap which 1uf (C1a/b) in this case not the out put cap (C5a/b)
am I wrong? sorry I am still newbee here

[Alastair E]

The Best Cap......

Is NO Cap!

IF you can omit or redesign to remove a cap, while keeping things more or less the same, then you'll be better off than spending silly money on Daft AudioFool Craps!

[cogsncogs]

Originally Posted by Palustris

Second, 470nF coupling caps are way oversize. 100nF will give a -3dB point of 3.4 Hz.

The 470n + 10n caps are "inside" the feedback loop and as such will have an effect on low frequency stability. There is a subsonic peak on the first anode(s). Lowering the value of the coupling cap will raise that subsonic frequency and it's barely stable as is. I did a simulation of the circuit and according to the phase measurements, it will more than likely motorboat around 0.2Hz if the cap is lowered to 100nf.

[Tony]

the circuit is complicated as i see it.....better sounds comes from simpler designs....

[Kay Pirinha]

Btw, cogsncogs,

you're a fan of Gentle Giant, aren't you?

[xneakers]

Hi,
Mundorf Silver Oil slightly emphasizes the high notes.

Jantzen and Auricap tends to have warmer sound.

You can decide which one suits you.

All caps above definitely noticeable in different.

Something must be very wrong if one cant hear the different.

Thanks.