Très intéressant: l'avis d'un tech qualifié sur le forum Fender:
I opened up a Super Champ XD this morning and I was very pleasantly surprised at the overall quality. I've posted a pic of the board in my profile if you're interested.
The board is well made, dual-sided, with plated-through holes, commercial grade thickness. One large board has the power supply, control interfaces, and tube circuits. A small board holds the DSP and a read-only memory chip that contains the SCXD personality.
All of the resistors in the tube circuits are half-watt or better, heavier than they need to be. All of the off-circuit ribbon cables and wires have a bead of hot-melt glue where they meet the board, so that they won't break from flexing or vibration. All of the screws have a dab of sealant; they won't vibrate loose either.
Half a dozen small switching and interface integrated circuits translate front panel controls into tone and volume actions. They're all bypassed to eliminate noise or glitches. The controls themselves are round pots with angled frames, similar to those on the Hot Rod Deluxe and Blues Deluxe, soldered to a circuit board, but attached to the front panel with nuts, not like the shaky knobs on the BJr and PJ.
All of the controls are digital. There's no tone stack or even a real analog volume control--all of the knob settings are translated into instructions for the DSP chip to look up the appropriate response for the chosen voice.
I was hoping that the analog/tube portion and/or power supply would be on a different board, but it's all on one.
Amazingly enough, the SCXD has adjustable bias! There's a big, blue, single-turn trimpot on the circuit board, up by the output jack. Mine was set fairly cold. Warming it up, however. didn't audibly affect the tone.
The amount of sawtooth on the plates is entirely normal, but more than I like. I'll probably add more filtering if I can find room for it. The 6V6s are running at 400V and Fender is using 450V caps. I'd like a little more margin there, but they should hold up OK.
The power transformer never gets more than moderately warm. Plenty of headroom there.
Overall, I'd say that the analog and digital engineers did a fine job with the SCXD. I think they could do a little more work on some of the voices, especially the clean jazz voice. It's way too bass-heavy; I play it with the treble on 10 and the bass no more than halfway. And it hardly responds to the gain control at all. Wouldn't it be cooler if it did some of that Wes Montgomery-style throaty breakup as you cranked it?
Meanwhile, other voices, like the Marshall, sound like they're supposed to, and even clean up to Bassman-like tones when you dial back the gain.
I'm digging this thing. I'll try a Ragin' Cajun in it later.
In rod we truss.
"Quelle opulence" - themidnighter
"It's sink or swim - shut up!"