Musical Fidelity X-Can V3 tweaks

Input Caps
Musical Fidelity fit 10uF polar electrolytics as input caps. It's bad enough having capacitors in the signal path at all but to fit polar electrolytics is just a big no no...... There is no DC across the caps so 10uF "non polar" capacitors are much better in this position and they sound a lot clearer compared to the polar types..... you could always fit 10uF film caps in place of the polar electrolytics but be warned, they would be very big! I have chosen just to fit 10uF non polar electrolytics and have bypassed them on the underside of the board with 220nF and 1uF film caps:

Parts / Accessories can be ordered from the Rock-Grotto Accessories Page

10uF non polar caps (yellow ones) fitted in place of the 10uF polar caps

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.

Output Capacitors
This is another key area of the amp that can be improved upon. Musical Fidelity fit two output capacitors per channel (2 x 220uF non polar) which are in parallel to make 440uF per channel. Listening tests with the WNA headphone amp hinted that 1000uF was the best value to use as an output cap and listening tests with the X-Can V3 confirm that 1000uF is indeed preferable to 440uF in the V3...... more bass extension and better dynamics.

Remove the 4 x 6.3V 220uF non polar output caps.

Fit 2 x 35V 1000uF Non Polar caps (lay them on their side) into two of the spare capacitor bays

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!

Spare output capacitor pads shown.... these can either be left empty or you can fit film bypass caps here.

I decided to fit WIMA 0.082 polypropylene caps into the spare bays which bypass the NP electrolytics.

I have since bypassed the two 0.082 polypropylene (output) bypass caps with a 220nF polyester and a 47nF polyester which has helped give the top end a tad more sparkle and clarity.

PSU Capacitors
Musical Fidelity may well have pulled out the stops and fitted an ALPS RK27 potentiometer but it's a pity they stopped there........ the rest of the amp is pretty much business as usual and that includes the same old el cheapo Jamicon 85c general purpose capacitors... don't get me wrong, there's nothing wrong with Jamicon general purpose capacitors but I'd rather find them inside a tumble drier and not inside a £250 headphone amp.

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!

X-Can V3 with stock Jamicon capacitors in place.

X-Can V3 with Pansonic FC capacitors on board.

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.

Bypass Capacitors

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.

Electrolytics bypassed with film caps. Worth trying but use more than one film cap per electrolytic.

More to follow...............



			Musical Fidelity X-Can V3 tweaks

			A few tweaks which will definitely bring out the best in your X-can V3

			*Input Caps* Musical Fidelity fit 10uF polar electrolytics as input caps. It's bad enough having capacitors in the signal path at all but to fit polar electrolytics is just a big no no...... There is no DC across the caps so 10uF "non polar" capacitors are much better in this position and they sound a lot clearer compared to the polar types..... you could always fit 10uF film caps in place of the polar electrolytics but be warned, they would be very big! I have chosen just to fit 10uF non polar electrolytics and have bypassed them on the underside of the board with 220nF and 1uF film caps: Parts / Accessories can be ordered from the Rock-Grotto Accessories Page 10uF non polar caps (yellow ones) fitted in place of the 10uF polar caps 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. Output Capacitors This is another key area of the amp that can be improved upon. Musical Fidelity fit two output capacitors per channel (2 x 220uF non polar) which are in parallel to make 440uF per channel. Listening tests with the WNA headphone amp hinted that 1000uF was the best value to use as an output cap and listening tests with the X-Can V3 confirm that 1000uF is indeed preferable to 440uF in the V3...... more bass extension and better dynamics. Remove the 4 x 6.3V 220uF non polar output caps. Fit 2 x 35V 1000uF Non Polar caps (lay them on their side) into two of the spare capacitor bays 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! Spare output capacitor pads shown.... these can either be left empty or you can fit film bypass caps here. I decided to fit WIMA 0.082 polypropylene caps into the spare bays which bypass the NP electrolytics. I have since bypassed the two 0.082 polypropylene (output) bypass caps with a 220nF polyester and a 47nF polyester which has helped give the top end a tad more sparkle and clarity. PSU Capacitors Musical Fidelity may well have pulled out the stops and fitted an ALPS RK27 potentiometer but it's a pity they stopped there........ the rest of the amp is pretty much business as usual and that includes the same old el cheapo Jamicon 85c general purpose capacitors... don't get me wrong, there's nothing wrong with Jamicon general purpose capacitors but I'd rather find them inside a tumble drier and not inside a £250 headphone amp. 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! X-Can V3 with stock Jamicon capacitors in place. X-Can V3 with Pansonic FC capacitors on board. 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. Bypass Capacitors 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. Electrolytics bypassed with film caps. Worth trying but use more than one film cap per electrolytic. More to follow...............