Tom Scholz Used An H910 In His Early Studio

[tbonuss]

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Aside from the doubler, which Tom states is used judiciously throughout the album, his other techniques are less exotic, though just as effective. "A plain old wah-wah pedal is very effective on certain things," observes the musician. "To some extent you can follow notes on the fretboard. To do it, you find two or three notes next to each other on the fretboard, and then find the position of the pedal that sustains those notes. As you play up the board, press the pedal toward the treble side to sustain the higher notes, or if you're playing bass notes, push back on the pedal to sustain them. It's a great effect, but a little difficult to control."
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This part from the posting above has me intrigued. I swear the XP100 has some kind of autowah going on for sustained notes with some of the factory presets. My regular Sustainor does it a bit, but the XP100 definitely does something like an autowah...or something. Maybe all of the Sustainors do it with the right EQ'ing? Maybe he built this Wah pedal technique into a filter of some kind?

I've always wondered what was going on with this. Anyone understand what I'm talking about?

[GuitarBuilder]

I suspect what you're hearing is the smart gate fading in and out. The Rockman design is unlike any other in that it is a Voltage-Controlled Filter (VCF) controlled by two signals: a high-frequency detector and an envelope follower. The "classic" noise gate uses an electronic switch or Voltage-Controlled Amplifier (VCA) to turn the gate off when no guitar signal is present.

In Tom's patented design, the VCF rolls off any frequencies above 1300 Hz at zero guitar signal, then shifts the roll-off point up to 20 kHz when playing at full volume. The roll-off point "sweeps" with the guitar envelope (volume); this is also the basic design of an Auto-Wah!

You have very good ears!

[tbonuss]

Thank you for the explanation, that is very interesting.

So the XP100 has a Smart Gate (or some like function) in it?

[RockmanCentralBob]

No, it doesn't.

[tbonuss]

So then it's not the noise gate...any other ideas?

[RockmanCentralBob]

So then it's not the noise gate...any other ideas?

I'm not an electronics expert, but I have hacked MANY Rockman modules and studied the schematics for a VERY long time.
So I'm offering what I think you could be hearing, but someone with proper electronics training may disagree/clarify....

In the compressor of the Rockman, I see what looks like some filtering (eq'ing) going on (ie- resistor/capacitor networks), and it changes based on the gain configuration. What it looks like is that for the various gain stages, (cleans~Heavy Distortion), there is different EQ'ing being applied, most likely for the mid range. And again, depending on the level of compression, it may react differently (stronger or softer emphasis on the frequency) depending on the signal level.

This is just speculation, but that's what it looks like to me. So for the cleaner settings, maybe not so much mid-range is added, but the heavier you get, the more "honk" is introduced. This is probably why everyone says it's so hard to remove that mid-range tone in a Rockman, because it's built into the compressor. It's also probably why on XPRa units that have the compressor bypass feature in the max gain settings, it doesn't have as much of that honk.

So, if that's true, then when you play harder, you may be hearing the mid being emphasized/de-emphasized, which could sound somewhat similar to an auto-wah effect being mixed in, I suppose. But again, this is all just speculation.....

[rbc]

This is just speculation, but that's what it looks like to me. So for the cleaner settings, maybe not so much mid-range is added, but the heavier you get, the more "honk" is introduced. This is probably why everyone says it's so hard to remove that mid-range tone in a Rockman, because it's built into the compressor. It's also probably why on XPRa units that have the compressor bypass feature in the max gain settings, it doesn't have as much of that honk.

So, if that's true, then when you play harder, you may be hearing the mid being emphasized/de-emphasized, which could sound somewhat similar to an auto-wah effect being mixed in, I suppose. But again, this is all just speculation.....

I've never seen the schematics for most of the Rockman gear, but I'll speculate that the goal was to simulate the sound, of a saturated output transformer of a tube amp. When the output transformer gets saturated, the bandpass of the transformer is said to narrow, depending on the degree of saturation.

[RockmanCentralBob]

I think it was more about simulating the cocked wah or MXR 6 band EQ tone he used on the first 2 albums. He clearly likes that tone because it fits in the mix better.