First, is there any way to tell the age of manufacture from a serial number? It’s BC010231. Does this mean 2001?
Next, I had a Mesa Mark V with a similar control of layout, and I was wondering if the circuit is laid out in a similar way, where the tone knobs are before the drive circuit and EQ sliders are after. The manual says the knobs are passive, so does that mean they’re all reductive and only cut frequencies?
Next, one peculiar thing is that the position of the gain knob on the channel I’m not using influences the behavior of the gain on the channel I am using. So if I’m using the green channel for clean (and red channel for distortion), if the red gain knob is all the way up, turning down the green gain below 9:00 doesn’t clean it up all the way or make it quieter, it just changes the tone to be more dull. But if Red gain is all the way down, turning down green gain will make it cleaner and quieter until there’s no sound at all. Is this normal or some poorly done modification from the old owner?
Last, does the Shift switch just lower the bass and treble levels overall to make the mids more prominent or what?
Okay, that’s all for now, thanks for your answers!
Generally the settings on one channel should not noticeably effect the sound of the other. If that is happening, either there is a bad switching device in one of the channels, or your hearing is super sensitive. Depends on the severity of the issue.
Shift actually shifts the entire tone stack to a slightly lower register.
Yeah, the issue with the knobs is definitely not subtle. Here’s a link so you can hear, with the red gain at zero, the green gain works as expected. With the red gain turned up, the green gain never goes silent but experiences a strange tone shift in the first quarter of its rotation.
And just to follow up a bit more, for the EQ kn obs and sliders, they are all post gain so should I think of the knobs as more wider controls and the sliders as fine tuners?
And final super stupid question, does the shift button actually change the tone stack curve in addition to lowering it or just flatly lower the entire thing? I’m asking because I’m sort of wondering what the “point” of the button is, so to speak. I mean, obviously the real answer is to use my ears and figure it out but I’m just curious for me design and technical standpoint.
my best understanding of the shift switch is that is shifts the frequencies of the tone stack to a more bassy register. when dave says lower he means of a lower frequency, not less volume. say (made up numbers) that normally turning up the “mid” knob would increase frequency response in the vicinity of around 1 kHz without the shift knob, with the shift knob that would change to e.g. (again numbers are made up) 700 Hz. to my ears it ends up sounding like a low-mid boost with the shift engaged, and makes the tone overall thicker and meatier. the overall effect of the switch does depend how the tone stack knobs are set, however. overall, on my 50CL (no eq) I usually leave it disengaged, but there are some cases where I engage it.
Thanks, that’s a really insightful comment and helps a lot! It sounded a bit at first like it was boosting the mids, but now I understand it better that it was probably just boosting the lower mids relatively to how I have the knobs set, since I usually keep the bass low and treble a bit higher, which masks the upper mid-range otherwise.