My ultimate experience with Musical Fidelity X-Can

[jokelo]

At first I really want to thank you Mike, for everything you have done for me. I appreciate your effort. This post has nothing negative to do with your work, because it is really outstanding, thank you.

About four to five years ago I bought X-Can V3 as it has been reviewed very good everywhere and gets big hype as being super headphone amp. When I got one, I was so happy to be proud owner of such equipment. For me it was very pricey piece of audio component.

After one year of quite little use, x-can started to give crackling and fading of sound on the left channel. Ok, back to shop that sold me it and there it goes to repair under warranty.
It took two months them to swap a single valve for it.

Got it back and thought "oh yes, now it's working. It was the valve causing this channel issue". Worked for exactly one year. Again left channel issue was back. Of course I thought it's valve again.

Did Google like hell and found Mike's site, and this forum. Thought that I order some GOOD valves from Mike, instead of those stock ones, that I was sure the were pretty bad ones. Also ordered some EH6922 Gold pins from other shop. Now I had two pair of better valves, that will have no left channel issue.

Swapped to EH6922, sweet. After 2 days of use, left channel started crap again. Then I started to try different things to find the problem. Changed interconnects sockets, changed headphones, connected amp directly to cd player. With no results. Always the left channel fading, what ever I did.

Got those 6h23n valves from Mike then. Swapped them in. They worked for two days again, until that left channel started shitting me again. After little discussion with Mike, he told me to tighten those valve base pins. This seemed to work.
Great. Again was pretty happy with my amp again, sound was really good and it was working. I thought that it must be the valve base then causing this issue. Ok, I will tighten those pins always when needed.

Then comes the summer, had one time this issue with left channel and tightened pins. Also swapped valves around. Again, problem solved.

Then comes autumn and winter. Here comes the trouble, left channel begin to bug every week. I tightened pins and swapped valves side by side every week for whole winter time. Always when I was going to listen to music I was aware that I might have to tighten those pins again before doing so.

Yeah, summer came and I was very mad about my amp. That piece of shit couldn't stand a week without tightening those pins. Then it worked like a dream whole summer. Thought that I managed to tighten them so good, the problem solved.

Ok, here comes the october again. Left channel bugging again. Tightening again. Works for 2 to 5 days again without problems. Tightening more. F**k it!

Thought that maybe Mike could help me. It must be those valve bases causing it. As reseatening and tightening always helped for some days. Ok, back to save some money. Now I want it to be done once and for all. Mike is a professional that can help me out. So, sent board to Mike. He did a great job of doing full caps and diode mod on it, changing valve bases, new valves. He even changed that gold quad phono socket. Ordered Little Pinkie too, if the problem could be that wallwart. So there really should be everything done to make my amp alive again and get rid of this left channel issue. Had so high hopes on this.

It came back from Mike week ago. I just have to admire Mike's work, I was like "whoooa!". It is now done, all is ok. Now just to listen some music. Yep, oh my god what sound! Absolutely stunning! My hassle with this amp must be now gone forever, it is a dream come true. Well, how wrong I again was. Yesterday it started again fading and crackling that left channel. It went away when listened about an hour. Had some bad thoughts about it... but was hoping it was just some sort of warm up issue.

Today morning, when amp turned on, left channel was crackling like hell and fading away. Opened up the case and swapped valves side by side. Again, problem solved for now. Amp has been on since then. I just don't dare to put it off, as I know I have to reseat those valves then again. Well, let it be on then until it blows. I just cannot understand this. I just can't. I've tried everything. I just well give up on this four years of terror this amp has given me. But I f**king won't! As far I've come I will clear what is this left channel crap. A curse on me?!?!

And again I have to thank you Mike, you have helped all you can. You did my X-can what you could, and I appreciate it.

[PinkFloyd]

Have you been using the same interconnects for all these years? It may be a pretty "out there" sugestion but (if you have) swap them round and see if the problem migrates to the other channel.

If not, then please send the amp back over to me, it sounds like there may be an intermittent connection somewhere on the board and when you press down (reseating the valves) it may just be enough to "make" the connection again.

I tested her for 24 hours and all was fine but if it's a loose connection / dry joint etc. then the problem will come and go.

I had similar with an old CD player and it turned out to be a loose pin on the RCA sockets.... resoldered it and all was fine again.

Don't worry, I'll sort it out for you

Mike.

[jokelo]

Yes same interconnects. But I have tried to swap them round, and the problem stays in the same channel.

This is becoming a double posting, sorry. But did not dare to put my "bleeding" to "work in progress" thread.

Most wierd thing is that it is making this only in the winter time... When it becomes a bit cold. It's not very cold in room, but could it be somehow too cold?

This is really sounding like mumbo jumbo... It seems to work fine now when it has been on for hours as the amp itself is warm all the time. Problems only begin when I put it off and then another day on. I will now keep it on for now... let's see what happens.

Thanks for offering to help me out. Let us wait until this christmas hassle is over, I will test it during christmas.

[Deleted]

Dec 18, 2010 21:04:05 GMT jokelo said:

Yes same interconnects. But I have tried to swap them round, and the problem stays in the same channel.

This is becoming a double posting, sorry. But did not dare to put my "bleeding" to "work in progress" thread.

Most wierd thing is that it is making this only in the winter time... When it becomes a bit cold. It's not very cold in room, but could it be somehow too cold?

This is really sounding like mumbo jumbo... It seems to work fine now when it has been on for hours as the amp itself is warm all the time. Problems only begin when I put it off and then another day on. I will now keep it on for now... let's see what happens.

Thanks for offering to help me out. Let us wait until this christmas hassle is over, I will test it during christmas.

A long shot. When you insert the RCA plugs SLOWLY, do youfeel the inner of the plug strike some resistance before the outer of the plug makes contact.
I have had to replace numerous RCA sockets over the years where the inner of the socket loses tension and the channel becomes intermittent.

[jokelo]

sandyk:

Mike already replaced those RCA sockets. Suppose it is not that...

[PinkFloyd]

Now I've had time to think about it.... the problem (break in track) will be situated quite close to the valve socket..... you have been "exercising" that area for quite some time and something has obviously parted company with something else.

Send the board back over to me and I'll trace the culprit. I am 101% sure it's a loose joint / broken track.

Just a case of finding it

Mike.

[PinkFloyd]

Don't worry.... it is "100%" likely to be a track that has semi parted with a pad..... I'll find it.

[elysion]

Dec 18, 2010 21:04:05 GMT jokelo said:

Most wierd thing is that it is making this only in the winter time... When it becomes a bit cold. It's not very cold in room, but could it be somehow too cold?

It's not weird. Probably that loose connection / dry joint is only a problem within a certain temperature range.

Years ago, I had a problem with a Misubishi DiamondTron 21" CRT monitor at work. After opening the windows of the office in the early morning, the green channel failed and almost everything on the screen changed instantly to an intense magenta (pink). There was a loose connection on that channel and it was somewhat sensitive to cold temperatures. We could reproduce that behaviour several times and the monitor was replaced under warranty.

Several years ago, I've seen also a PowerMac 7600 that had a memory DIMM that was sensitive to cold tempartures. I could indentify that failing DIMM which was causing hangs of the whole system at bootup if the temperature was too cold. After removing that DIMM the PM7600 has showed normal behaviour again and it has booted flawlessly even at very cold room temperatures.

[jokelo]

Mike, I will send it to you after christmas...

[jokelo]

Packed and ready to be shipped on monday. God I hope this works. Putting my all hopes on you Mike. I'm loosing my mind with this amp.

When she has no issues, she is just greatest thing in the world and I just love her.

When the crackle comes in I'm like ready to throw her out of the window.

She is just like the rest of the women.

[elysion]

After my last post in this thread, I had also a (most likely minor) problem with my X-Can V3. I've noticed some noise on the left channel which was not there before.

I still have not much time at the moment because my new apartment isn't fully furnished and most of my gear is still packed in boxes.

In my case, I'm almost sure it's a failing tube (too bad since I like that type of tubes... at least I have two pairs of the same type as spare). I will try to swap each tube into the other socket and to see if the problem moves from one channel to the other.

I guess the amp itself is working perfectly (like it did the whole time since I got it back from Mike after modding). In the first few weeks I've noticed also some slight channel imbalance but that issue disappeared after a few weeks burn-in. If one of the tubes is really failing, then I guess that tube was also responsible for that slight channel imbalance that disappeared later. Perhaps it also related to the current temperatures. The V3 didn't get warm even if I've left it on continuously.

My primary goal at the moment is to finish everything related with the new apartment. Things should normalise after that – finally.

I regard the modded V3 still as the best amp in my armory, closely followed by my Neco amps. I've switched to my Neco Mosfet V2's for the next few days.

I like both solid-state and tube amps and I don't care what's inside an amp as long as it sounds good. But IMO there's is one advantage of solid-state amps in comparison to tube amps: Solid-state can be more reliable than tubes (but that is IMO not an absolute rule) since solid-state opamps have usually a longer lifetime than tubes. My six Philips E88CC SQ tubes are from the 60's and have been sold as NOS (5x) or slightly used (1x). I've bought them from two sellers inside Switzerland and the overall price was cheap. It's not a big financial loss, but I like that type of tubes and every failing tube is somewhat an emotional loss. I can't expect that those tubes work for 20 years while their age is around 50 years. Many tubes are sold as "NOS" or "unused", but in the end, there's no real warranty for that claim unless you have a tube tester. I can't complain since I got those tubes for a good price...

Maybe a good idea to order a couple of other tubes from Mike (after I've finished everything related to the apartment).

[Deleted]

Have you tried cleaning the valve pins, then carefully reseating the valves again ?

[elysion]

Dec 25, 2010 21:07:54 GMT @sandyk said:

Have you tried cleaning the valve pins, then carefully reseating the valves again ?

No. But I will do that. Thanks for the hint.

I thinks it's best to do the tests after I've finished all the things that I have to do for my apartment. It's a good a occasion to switch back to solid-state (Neco's) for a few days.

I'll have also closer look on the sound signature of the AD8160 opamps in the Neco's. I like the AD8160's, but Israel has tested also the Burr-Brown OPA627 as alternative and Mike has also mentioned the AD843. I'd like to know what I don't like exactly with the AD8160's. It's somewhat strange (since I like the AD8160's), but the Philips E88CC SQ tubes in the X-Can V3 gave me a more natural, organic presentation.

I'm using the Neco Portable V2 often with one of my Behringer UCA222 USB DACs and the Burr-Brown PCM2902 inside the UCA222 gives an interesting sound signature together with the AD8160 opamps. It's not as sweet as the PCM2902 is with other amps. I think the PCM2902 (and other Burr-Brown opamps/DACs) are sometime too sweet sounding at all.

[mrarroyo]

So, what happened after you cleaned the pins?

[robbee]

I just received my V3 upgrade kit from mike so I will be doing my mods myself this weekend. I opened the case to see what I was dealing with and I have to say I was surprised to see the state of the original MuFi soldering!!!! Dull grey many looking like cold joints.


I have a V8 as well and it had a similar problem as you have described. Less than one year on the tubes with fairly light use. I assumed it would be the Valves and have a new pair on order. Thanks for the posts guys, I will to take a look inside the V8 now to see if the soldering looks as bad as the V3!!!.

RobB

[jokelo]

As for an update on my case...

I did send my v3 back to Mike. He resoldered the whole board. Seems like it worked for me, at least I've been using my amp for about two weeks now without problems. Hope the problem just stays away this time.

Maybe it was some loose joint then causing all this headache after all.

When it was under warranty repair, MF repair told me they checked all the joints and there were no problems on them. So they only changed one tube. I lived with it until problem came back again and that warranty time was over...

[PinkFloyd]

Feb 3, 2011 9:02:51 GMT jokelo said:

As for an update on my case...

I did send my v3 back to Mike. He resoldered the whole board. Seems like it worked for me, at least I've been using my amp for about two weeks now without problems. Hope the problem just stays away this time.

Maybe it was some loose joint then causing all this headache after all.

When it was under warranty repair, MF repair told me they checked all the joints and there were no problems on them. So they only changed one tube. I lived with it until problem came back again and that warranty time was over...

Don't worry,

The problem is cured mate

Mike.

[elysion]

Jan 4, 2011 23:30:04 GMT mrarroyo said:

So, what happened after you cleaned the pins?

This answer is really late. Better late than never.


I had a nice time with my Neco's and a few other amps (stock V-Can with replacement SMPS PSU's, PreSonus HP4) during the last weeks.

A few days ago, I decided to go with valves again and I opened the V3 to see what happened. Long story short: No testing was needed at all. The left tube had almost the look of a burnt out light bulb. The top of the tube was noticeable darker than the right tube. Both tubes had the same appearance as I put them in the sockets the first time. I'm almost sure that I see some darker areas of the glass also at the bottom of the tube.

Unfortunately, I can't make photos that show this as clearly as I can see it with my eyes.

The left valve on the images is from the left channel, the right valve is from the right channel.









Replacing the tubes solved the problem. The replaced tube on the right channel is still working without problems.

[mrarroyo]

All is well that ends well.

[jokelo]

Feb 3, 2011 9:02:51 GMT jokelo said:

As for an update on my case...

I did send my v3 back to Mike. He resoldered the whole board. Seems like it worked for me, at least I've been using my amp for about two weeks now without problems. Hope the problem just stays away this time.

Maybe it was some loose joint then causing all this headache after all.

When it was under warranty repair, MF repair told me they checked all the joints and there were no problems on them. So they only changed one tube. I lived with it until problem came back again and that warranty time was over...

Nope... Yesterday problem occurred again. Swapped again valves side by side and the problem was gone.

Again.

I'm out of ideas now what could be possibly causing this.

Pretty frustrating.

It's been working these few months with no problems what so ever.

Anyone with an idea what to try next? Anything?

[Deleted]

If it happens again after some time (I expect it will) just rotate/wiggle the valves in their sockets or pull them out and re-insert.
If this helps (again) it's probably the valve sockets.

[jokelo]

May 26, 2011 16:38:11 GMT @solderdude said:

If it happens again after some time (I expect it will) just rotate/wiggle the valves in their sockets or pull them out and re-insert.
If this helps (again) it's probably the valve sockets.

Mike have already fitted new ceramic valve sockets, so I suppose it is not those sockets causing this. As this happened with original MF sockets and with these ceramic ones.

[jokelo]

Well, happened today again. First I tried to change interconnects from left to right and right to left. Problem stayed at left channel. Bit wiggle of connects, no help, nothing. Headphone jack out and then in, little round movements on it. No help.
Power off -> 2 minutes -> power on. No help.

Opened up the enclosure like before, took PCB out and touched a bit every cable inside. This time I did NOT even touch those valves. Put everything back together and power on -> Tadaa the problem was gone.

So after this I begin to think that the problem is in cables/their connections. All I did is just touched those cables and opened the case exactly like before.

[Deleted]

that is very likely !
Simply take out those interboard connectors and solder the wires directly....
connectors (tube sockets are connectors too) in general cause most intermittent problems.
Next are pots, switches and relays.

tapping on it while playing with the rear end of a screwdriver sometimes can show where the problems are. a disadvantage may be one taps the fault 'away' and doesn't show itself anymore for quite some time, adding to the annoyance.

[jokelo]

I am now trying to reproduce the problem and figure out which cable is to blame. Just that I hope it is a cable causing this.

As I have no soldering experience, I will try everything else for now.