Musical Fidelity X-Can V3 tweaks
A few tweaks which will definitely bring out the best in your X-can V3
Parts / Accessories can be ordered from the Rock-Grotto Accessories Page
If you are absolutely certain that your source has no DC at its output you can dispense with the 10uF input capacitors altogether. MF fit these input caps as a belt and braces safeguard against any DC entering the amp but 99% of modern CD players will not have any DC at the output as there will either be output caps or a DC servo fitted to block any DC entering the amp......... it's always worth checking and never "assume" the outputs of your CD player are free from DC.
If there is no DC at the outputs of your source then you can remove the 10uF input capacitor and fit either an axial ferrite bead inductor or a zero ohm link. If RFI is very high in your area then the ferrite inductor is the best choice in this position.
This will leave two spare capacitor bays on the PCB. As the tracks are paralleled and you now have 1000uF per channel you can either leave these bays empty or fit more capacitance into the spare bays. I chose to fit 2 small value polypropylene film caps which effectively are connected in parallel to the 1000uF caps and act as bypass caps. The 1000uF cap per channel sounds a LOT better than than the 2 x 220uF (440uF) per channel... you are replacing 2 electrolytics per channel with "one" of a larger value so it only makes sense that the amp should sound a lot better with one electrolytic cap per channel less for the signal to pass through and the extra 560uF per channel works wonders in the sonic department!
The X-Can V2 responded very well when it was fitted out with better quality capacitors (hundreds of people have e-mailed me enthusing about what a MAJOR improvement the capacitor swap in the V2 brought about) and the same holds true with the V3.
Panasonic FC series capacitors are my favourite in the V2 / V3. I've tried many caps in the V2 including ELNA Cerafine, ELNA Silmic, Dubilier, Forever, Rubycon and Nichicon and none of them quite match the Panasonic FC... their low ESR and "house signature" just bring the best out of the X-Can V3... give them a spin under the bonnet, you may like them!
There are 6 x 2200uF, 4 x 1000uF and 4 x 100uF caps to be replaced with Panasonic FC's. I replaced the 6 x 35V 2200uF and 4 x 35V 1000uF all with 35V 2200uF Panasonic FC (6 x 2200uF replaced with 2200uF and 4 x 1000uF replaced with 2200uF) I replaced the 4 x 35V 100uF Jamicons with 4 x 35V 100uF Panasonic FC.
Note: Further to fitting the Panasonic FC series of capacitors in the V3 I fitted some Panasonic FM series caps in a V2 with very good results. These have even lower ESR than the Panasonic FC so are probably a better cap to use in the V3 if you can source the 2200uF types. RS components stock them but they don't go as high as 2200uF in a 35V package.
You can, if you wish, fit bypass capacitors in parallel with all of the electrolytics. I tried this and, to be honest, I couldn't hear much of a difference with the electrolytics bypassed with film caps..... this is an area you can experiment with and it's probably better if you bypass the electrolytics with two (or more) film caps of different values (say 1uF and 220nF) It really is a case of suck it and see and some people swear by fitting bypass caps... the caps in the signal path (input and output) certainly do respond well to bypass caps (sounds better) but IMO the caps in the PSU section are best left alone as they are very low ESR and, unless you fit 2 or 3 bypass caps to each electrolytic, bypassing them can actually make the amp sound worse.
More to follow...............