Fault finding X-CANS / V2 / V3

[PinkFloyd]

I've been meaning to do this for quite some time and will list some fault conditions and possible remedies here. It'll take me a while to list all the combinations I've come across but will add to this thread when I remember them.

1: X-can V2 - Valves glow and LED lights up but no sound from either channel. Solution = Replace the ZTX653 / ZTX 753 transistors on the PSU board with new ones.

2: All versions of X-Can - noise from one channel. Solution = swap valves over and see if the noise flips to the other channel, if so replace the 6922 valves with new ones.

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

[mbspider]

I hear some soft hum on the right channel of the V2, and i hear it only within the volume range 1/4 up to 3/4. Perhaps a grounding problem?

[PinkFloyd]

1: X-can V2 - Valves glow and LED lights up but no sound from either channel. Solution = Replace the ZTX653 / ZTX 753 transistors on the PSU board with new ones.

LED lights up, valves glow but sound is extremely distorted. Solution: Replace ZTX653 / ZTX 753.

[PinkFloyd]

Hum: Most common culprit is the RCA (phono) sockets. With constant ins / outs the ground leads can snap (do snap!) so first place to look if your v2 is humming is the quad phono socket. This is very common if you run your amp "naked" (ie: out of the enclosure) to prevent this always hook your interconnects up with the PCB in the enclosure and with phono assembly securing screw in place.

[PinkFloyd]

Amp is dead and you're getting sparks across the capacitors ....... 653 / 753 need replacing.

[sinwerm]

Well, just installed the Alps volume pot and am now noticing that when I touch the knob or shaft I get a slight bit of static and the hum that usually means a ground problem. If I turn it with a glove on no hum no static. I will look at the RCA ground first any other suggestions ? thanks.

[PinkFloyd]

sinwerm said:

Well, just installed the Alps volume pot and am now noticing that when I touch the knob or shaft I get a slight bit of static and the hum that usually means a ground problem. If I turn it with a glove on no hum no static. I will look at the RCA ground first any other suggestions ? thanks.

You're using a metal knob? This happens sometimes, you have to insulate the shaft from the knob....... a small strip of insulating tape wrapped round the shaft usually helps. If it doesn't affect the music and only happens when you touch it then I'd leave it be or if it's really pissing you off then fit a plastic knob

[sinwerm]

Right on the money ! Yes a nice aluminum knob. Thanks , easy solution. Perhaps some plastic set screws also...

[marcm09]

dont need plastic screws as the shaft will be insulated with tape- also heatsrink will make a nice job ...

[sinwerm]

Actually the heatshrink is a perfect idea thanks , always have some of that around.

[PinkFloyd]

I'd stick to wearing the rubber gloves.... more eccentric...... a pair of thigh high rubber boots and a gas mask would be the ultimate in hum free listening apparel.... clothing for the true audio conneissuer ;D

[sinwerm]

LOL I thought that sounded a little strange after I wrote it but I meant I isolated myself with a napkin. Though sitting in a wing chair with a nice vodka and listening does sound appealing sans white gloves eccentric ?? me ? never ! Well off to polish my Elvis tea cup collection with a tiny toothbrush.
BTW I do possess a thigh high set of rubber boots but purely for trout fishing I swear ;D

[PinkFloyd]

sinwerm said:

I isolated myself with a napkin.

A rubber napkin? wow you people over there are strange.... I can only stretch to paper napkins and that's strictly at Christmas... I don't even know what to do with a napkin... does "one" blow "ones" nose with a napkin or use it to turn the volume up? Rubber napkins? you don't know you're born

[PinkFloyd]

mrarroyo said:

You forgot the diver's suit.

Come on man that's perverse! Thigh high boots and rubber gloves are audio essentials but a divers suit could be seen as "perversity" to non audiophiles (deaf bastards)