BONTEMPI Minstrel BETA [] analogue keyboard with nice accompaniment and monophonic envelope

This ancient Bontempi keyboard has a lightweight grey plastic case with detachable keyboard lid and pull- out handle. I don't know how old it is, but the analogue hardware looks like very early 1980th; it has only a monophonic envelope (i.e. when in piano mode a key is pressed, any held down keys play at full volume again) and sounds very home- organ- like. The analogue drums distort but it has an astonishingly versatile accompaniment with arpeggio.

A midsize keys version of this instrument with smaller case was released as Bontempi Minstrel Alpha.

main features:




What I particularly like with this keyboard is the very versatile accompaniment; e.g. the arpeggio changes depending on how many chord keys are pressed and whether it is in fingered or single finger chord mode. The accompaniment accepts also any non- chord key combinations and can e.g. play a sequence of the same note from different octaves etc. When "chord memory" is off, the accompaniment falls silent by releasing the chord keys (in synchro mode rhythm stops too?), which makes it possible to play with rhythms in interesting ways. What I like less is the monophonic envelope in piano/ harpsichord mode and that of the only 6 sounds 2 (organ and horn?) sound almost identical.

I yet couldn't find out how the main and chord sounds are generated. (The keyboard stands in another city at my parents where I have no oscilloscope etc.) The waveforms seem to leave the soundchip somewhat encoded or multiplexed, because by connecting an amplifier I hear only digital pulses and the arpeggio and bass squarewave tones, but not the main and chord voices. Possibly they are decoded by some 74LS in between or even generated outside by something analogue; e.g. the oboe timbre is very different from squarewave, but it also may be just a filter. On the 28 pin main CPU(?) that is connected with the keyboard stands "~ S/B 8335, COP420-KPN/N, 27430700", on a 24 pin soundchip that outputs at least arpeggio, bass, envelope signals and rhythm trigger pulses stands "AMI 8340WN, 27430520, KOREA".

At the case bottom there is a sticker "HB 412.15"  and the following embossed text:
Design Guigiaro

Made in Italy - Fabriqué in Italie
Potenza Picena (MC)

HB 412.15Someone told me by e-mail that Guigiaro was a famous automobile designer from Turin (Italy) who e.g. designed the Volkswagen Golf and the Panda and Punto by Fiat (IMO all quite boring and way too rectangular looking cars). His company is named Italdesign.

A longer 49 keys variant of the Minstrel Beta was the Bontempi Minstrel Delta. It was also released in a silver metallic version with additional red button as Bontempi Master MB 424 and likely as Bontempi X301. A Beta variant with red button was released as HB 414. Most variants were also made in white.
A Minstrel Delta variant with 10 preset sounds and red button was released as Bontempi Minstrel Gamma. (Photos taken from eBay.)

A supposingly quite similar 49 keys stereo variant of the Minstrel was the Bontempi ES4900 Stereo and the MRS 49 (which had the same case style like the Bontempi M40). The same stupid monophonic piano envelope but much more features (e.g. programmable drum & chord pattern) has the Bontempi Eclipse (I own one). Another analogue keyboard with some similarities (and polyphonic piano envelope) is the wonderful Bontempi MRS 52/D. Large Bontempi ES series keyboards seem to be the direct successors of the Minstrel series; even a fullsize 61 keys stereo keyboard was released as ES5800, which even had MIDI but in spite of this still only 6 sounds and 8 rhythms like the Minstrel. But in the ES series also simple mini keyboards like the ES3000 and ES3100 were made, those had badly distorting digital sound of very poor quality.

 removal of these screws voids warranty...    
back to tablehooters collection