Roland HP-3700 (1990)
A 1990 digital piano that won a magazine award for its keyboard feel and shipped with a MIDI implementation that transmits pedal data. The record has almost entirely forgotten it.
Overview
The Roland HP-3700 is a digital piano released in 1990. It comes from the window when home digitals were still finding their feet - good enough to gig, affordable enough to keep in a living room, and different enough from one another that a magazine could hand out awards for the differences. The HP-3700 took one. In an April 1991 Audio-Collection group test of digital pianos in the roughly $2,995 - $5,000 range, it won the magazine's "Best Keyboard Response" honor (Audio-Collection, April 1991, p.143). That's the award that says the action feels right under the fingers, which a spec sheet can't tell you.
The instrument's identity is a little slippery in the documentation. Roland's owner's manual refers to it jointly with its sibling as the "HP-3700/2700," and the service literature says the two share a main board assembly. The variants "HP 3700" and "HP3700" also turn up. The owner's manual describes the sound source as an "Advanced SA Process" digital engine, which tells you it's a sample-based piano without telling you much about the samples. The tone list, as reported by at least one retailer, runs to six: Piano 1, Piano 2, Honky Tonk Piano, harpsichord, Vibraphone, and electric piano. That list is single-source, so treat it as indicative. It does line up with what the period review heard.
The keyboard is the headline. Sources describe 88 fully weighted full-size keys with touch sensitivity but no aftertouch. Touch sensitivity is what makes a digital piano feel like a piano and not a synth with a piano patch. One source calls it a weighted hammer action, which is the mechanism behind that feel. Whatever the exact internal description, the reviewers who played it in 1991 thought the response was the best in the group.
Key Features
88 Fully Weighted Keys with Touch Sensitivity
The HP-3700's keyboard is 88 full-size, fully weighted keys with touch sensitivity — and no aftertouch. That last omission is worth naming plainly, because it tells you who this piano was for. Aftertouch is a synth player's tool; a pianist doesn't miss it. The weighting and touch response are what make the instrument feel like a piano, and they're precisely what the Audio-Collection reviewers rewarded with their Best Keyboard Response award (Audio-Collection, April 1991, p.143). One source describes the action as a weighted hammer mechanism, which is the design that gives the keys their heft and their rebound. For a 1990 home digital, getting this right was the whole ballgame — a piano that feels wrong is a piano you stop playing.
Advanced SA Process Sound Source
Roland's owner's manual names the tone generation as an "Advanced SA Process" digital sound source. The name is period marketing, but the idea is plain: a sample-based piano engine, not an analog synth dressed up as a piano. The manual doesn't give sample rates or voice counts, and no polyphony figure has surfaced in the Archive's sources, so how many notes it can play at once is not on record. The sound set goes beyond pianos. Harpsichord, vibraphone, and electric piano are all named in the period review, and the six-tone list adds a Honky Tonk Piano to the two main piano voices. The review also noted that Roland's corporate family had recently absorbed the Rhodes name.
Sound Switching While Sustaining
The Audio-Collection reviewers singled out one feature as then-uncommon on home-oriented instruments: you could call up a new sound while the previous one was still ringing (Audio-Collection, April 1991, p.85). That means a chord can decay naturally while you reach for the vibraphone, instead of cutting off when you change voices. The review treated it as a relatively new capability for the home market.
MIDI Implementation with Pedal Data
The HP-3700's MIDI earned passing marks from the reviewers, with bonus points for a couple of specifics (Audio-Collection, April 1991, p.86). It transmitted damper and soft-pedal controller data, so a sequencer or a second sound module could hear the pedals as well as the keys. When the keyboard was transposed, the transposed note values went out over MIDI rather than the physically played ones. That saves grief when recording into a DAW or driving an external module. Neither feature was universal in 1991 home digitals.
Historical Context
The HP-3700 arrived in 1990, as digital pianos were settling into a recognizable category: weighted actions, sampled pianos, MIDI, and a price within reach of a serious home player. The Audio-Collection roundup that reviewed it in April 1991 covered digital pianos in the roughly $2,995 - $5,000 range, which puts the HP-3700 in the upper-middle of the home market and not at the budget end (Audio-Collection, April 1991, p.84). One source characterizes the instrument as notable for its sound quality and refined design and credits it with setting a trend for digital pianos. Another describes it as aimed at players who primarily want a quality piano sound and keyboard feel. Roland positioned it for both professional and home use, and the owner's manual's joint "HP-3700/2700" framing suggests it was sold as one half of a two-model family. The exact production run isn't documented.
Collectibility & Value
There is no reliable current market price for the HP-3700 in the Archive's sources. What does circulate is parts: a replacement "E" key for the HP 3700 has turned up listed on eBay, so individual keys are replaceable and at least some owners are keeping these alive. A service case is documented from December 2023 involving a unit with fluid damage. Seller descriptions tend toward the obvious ("in good condition," "never needs tuned"), which is true of every digital piano and not especially useful. If you're shopping, test the keyboard response in person. No failure pattern is documented, so you're evaluating the individual unit and not a known weak point. Parts availability is likely to be the limiting factor over the long run.
Similar items on eBay
No exact Roland HP-3700 listings are live right now — these searches show current Roland and similar vintage synth gear on eBay:
As an eBay Partner, we earn from qualifying purchases. This helps support our independent vintage technology research.