[Sampsa]

I want to replace the output capacitors in my MF A3 CD. They're Teapo 47uF/16V non-polar electrolytic. I've thought of Black Gate 47uF/50V N-series non-polars, but what other, possibly better choices are there? I'm hoping for a warm, full sound.

[Occam]

Sampsa,

I'm not privy to the schematic or layout of the MF component so I can speak only in generalities.....

1.  Shoehorning anything other than a small electrolytic onto the circuit might be problematic.
2.  The BG N caps make superb coupling caps.  I don't know what component you are feeding from the MF component (which is functionally presents an impedance in paralell with the output impedance of the MF component), but a BG N 16v 33uf should present a sufficiently low corner frequency, be about half the price, and might be easier to fit.
3. If you're ordering your caps frm Michael Percy, you might consider also ordering 2 Nichicon Muse KZ of proper ratings to try. These should be 'warmer' sounding, but will probably not as resolving. (if you PM me with your address, I'll be glad to send you 2, gratis. They're oversized for your needs, 100uf 50v, but can give you an idea of their sound qualities)
4. This last comment is purely anectdotal. While BG caps are know as the Caps That Must Not Be Bypassed, some who's opinions I trust have commented that bypassing BG Ns with a ROE MKP1837 .01uf cap, producces no negatives and adds 'color and warmth' to an already superb sound, FWIW...
http://www.mouser.com/index.cfm?handler=displayproduct&lstdispproductid=381412&e_categoryid=496&e_pcodeid=75023

[eico1]

measure the dc offset and see if you need any cap at all, or does your pre-amp have a cap at the input anyway?

steve

[Sampsa]

I'm not privy to the schematic either and don't really have the expertise to second guess the actual design - hence, I'm only changing parts for better ones. But that bypassing option sounds very reasonable.

The amp is MF A300 integrated, by the way, and I have yet to check if it has input caps.

[kana813]

Sampsa- you don't need a 16 volt cap on the outputs, the NX47uf/6.3v
will work just fine, or you could do a "Super-E" combo using two
NX22uf/6.3v caps.

The BGs are great in this type of application. In low voltage applications
they can take a long time to settle. A burn-in disk can speed this process.

You should also upgrade some caps in the power supply.

[Sampsa]

Thanks for the suggestion, but I'm quite hesitant to go for lower voltage than is already there. Why do you think it would work?

Actually, I already changed the PS caps to Nichicons, added a Schaffner FN2080 AC filter, took out AC filtering caps, two ferrite chokes from the AC and one from the analog output, and with the help of a friend changed the op-amps, removed muting transistors and RF caps from the analog output (hope I got that right).

[kana813]

Sampsa-

I know it will work, because I've done this on mine and a number of
other CDP/DVDPs I've modified.

No CDP or DVDP I've seen puts out more than 4 volts, on the analog outputs. Check the specs on your player's output voltage, it's probably under 2 volts.

The manufacturer uses a 16 volt part, because they buy them by the thousands for use in a number of circuit postions.

The same thing goes for the cap on the power supply which are on the 5 volt or 3.3 volt rails. N or NX caps rated at 10 or 6.3 volts make a big improve in the reducing ripple noise of  switch mode power supplies(SMPS).

You should have replace the prerectification AC line filter caps in the power supply, with something like a Auricap. the SMPS are sensitive to AC line noise, plus by removing the ferrite on the AC input
you're now pumping more digital noise back into the AC line, which can
effect your other components, if you don't use a power conditioner with isolated outlets.

[Sampsa]

I don't think I need the AC filter caps or ferrites anymore, since I put the Schaffner filter in there. And if I haven't entirely misunderstood what SMPSs are, this CD player doesn't have one. There are diode bridges to do the rectification.

Schaffner Filters (look for FN 2080)

[eico1]

I don't think I need the AC filter caps or ferrites anymore..

for someone who only this morning didn't feel qualified to remove an output cap,  this must have been quite an academic day! :)

More seriously, when it comes filtering rfi signals of this sort you cannot swap out components as the Q factor and other parameters will vary to the extent of mis-aligning such tuned circuits.

I'd think the guys at mf would have this worked out to a recipe by now.

steve

[Sampsa]

Well, I sometimes learn fast (Actually, I felt unqualified to change the size of the cap, but replacing it with a similarly-sized one is fine, and the other mods were done, like I said, with the considerable help of an expert friend - in the more complex ones, he explained what he was going to do and then did it.)

More seriously, I'd be surprised if the AC filter caps and ferrites would still be needed after the Schaffner filter installation or if that had any adverse side effects. The objective is to get as clean a 60 Hz sinewave and so there's no real tuning to be done.

But I can see that removing the ferrite and RF caps in the analog output might affect the tuning of the circuit. I'd still be surprised if that happened, but can't quite explain why.

[kana813]

"More seriously, I'd be surprised if the AC filter caps and ferrites would still be needed after the Schaffner filter installation."  

Sampsa-

I'm sorry to inform you, but the cheap caps inside the Schaffner can not compare to Auricaps and the other caps you installed in the power supply can not compare to the performance of Black Gates.

Have fun with your mods.