I thought I'd take a few minutes to talk about the history of the Rockman. There are several different models that have different features and capabilities. I owe a debt of gratitude to Jark for his page on the Rockman headphone amplifiers: http://www.rockman.fr/Reviews/Rockman.htm
His work on this is a key reference for this article. It's not my intention for this article to replace, but rather complement Jark's article. I've personally owned the original Rockman and a SR&D Rockman Guitar Ace, along with a Dunlop Rockman Guitar Ace. In putting together the article, I spent some time reading the user manuals to better tell the story. Others may be able to add their experiences with using the different versions of the Rockman. All that being said let's talk about the Rockman.
The original Rockman was released in 1982. It includes an amplifier simulator, stereo chorus and reverb. It has two clean sounds, along with "Edge" and a distortion modes. The two clean modes are differently EQ'd, "Clean 1" targets the electric guitar, while "Clean 2" is recommended for a wider range of use, including acoustic guitar, keyboard and vocals. The "Edge" setting produces what is described as "subtle" distortion, that will clean up when playing softly. The chorus and reverb are tied together, both being on when the switch was set to normal. You can disable the chorus or reverb, but not both at the same time. The Rockman requires eight AA batteries or an adapter for power.
Production of the Rockman Ultralight, began in 1983. It was a more economical alternative to the Rockman. It is very similar to the Rockman but lacks the reverb. Uniquely, the chorus can be disabled, providing a dry output from the amplifier simulator. Both the original Rockman and Ultralight models were continued until 1984.
1984 brought a new family of Rockman products. This included the X100, Soloist and Bass Rockman. This lineup continued to be produced until 1994. The X100 is very similar to the original Rockman in its feature set, but uses a different clipping stage in the amplifier simulation.
The Rockman Soloist was positioned as a lower cost Rockman product. It does not have the "Clean 2" voice. It also has different choices for effects, including a setting for chorus and a "stereo" setting that has a fixed 25 millisecond delay. It can be set to "Mono" output, removing all the effects.
The Bass Rockman features clean and distortion modes that include chorus. Dry output is available when the chorus switch is set to "off". There are three EQ presets for what is described as "Fat", "Mid" and "Bright". There is a high frequency clipper, recommended for use with a pick or "snapping" the strings. There is a high frequency compressor and sustain switch, primarily intended for changing the sustain of the bass in different ways.
The Ace family is a much simpler type of Rockman that doesn't have effects and uses a single 9-volt battery or power supply. The focus was having a more cost effective product. The Guitar and Bass Ace were first released in 1990. The Metal Ace was released in 1994. The Guitar Ace and Metal Ace have identical controls, but the Metal Ace is advertised to have a "brighter" sound. The amplifier distortion is toggled using the "cln/dist" button. The character of the distortion can be changed with the "semi/hvy" button. Semi-distortion behaves much like the "edge" setting is described to, in the Rockman and X100 product. The Bass Ace has the most spartan controls, including mid and treble boost buttons.
1994 marked another milestone for SR&D, beyond product releases. Dunlop Manufacturing acquired the entire Rockman line. Dunlop still sells the Ace family and you can buy them new. It's interesting to note that reviewers on the Guitar Center, Musician's Friend and Amazon web sites have commented on the obvious differences of the Ace family, compared to earlier Rockman models. I hope Dunlop noticed.
So as my personal holiday wish, I'd like to see the X100, Soloist and Bass Rockman back in production. I think the feature mix of these three products are compatible and don't compete with each other too much. They also stand apart from the Ace family as a higher tier product. The youngest of the SR&D Rockman's are around 20 years old. They won't present as much competition as they once might have. It might also be possible to use their carefully refined analog design as a selling point in some quarters. Boston is releasing their new album "Life, Love & Hope", scheduled for release this December. Perhaps Dunlop will see enough of a market to do another production run. If you agree with me, please bug Dunlop about that.
So that about covers it. That's my 10,000 foot view of the Rockman line. I hope that you find it useful. Comments and questions are welcome.