There are a couple of ways to go about this, but I think that I’d go with the following approach. I didn’t reference the original recording. I just went with the description & routing diagram (and I’m programming it from an H9).:
You’re going to need the latest TimeFactor & H9 Control software installed, and a working expression pedal. This particular preset won’t mute the dry input, but it’ll cover the other requirements. If it’s a Roland Space Echo that the article references, then maybe similar settings in the Tape Delay algorithm would give you a closer match.
First, you’ll have to split the signal out to both “HiWatt” sides. In H9 Control, go to the Pedal tab, then select General Settings, and Routing. Set it to Wet/Dry, then go back to the Presets tab. Under the More dropdown (upper right), you’ll now see a Routing selector. Choose Wet1/Dry2 to match the HiWatt split in the diagram. On the Timefactor, Output 1 is going to be the wet signal, and Output 2 will send out the dry signal. Send these out to the two amps / simulators / channels of your choosing.
Also under the More dropdown, select EXP controls input volume. Now when you push downward towards the toe, your playing input will fade into the delay buffer. When you pull back towards the heel, it’ll be dry-only. But the captured delays will continue to repeat until fadeout. Again, the dry signal will always be present on the rightside HiWatt (in this setup).
You may / may not want to increase both FEEDBACK A & FEEDBACK B. I guessed at about 20 seconds (or 14-16 repeats) until it’s virtually inaudible. You can bump up the MOD DEPTH for a little variation, or adjust the FILTER & BITS for a more modern sheen.
That sounds like a plan…. i’ll try this out in the next days…