[sdiy] My new ESQ-1

[rkmoore at memphis.edu]

I think that the ESQ-1 has the keyboard with the weird little springs 
that make contact with buss bars.  Groups of keys (maybe groups of 
eight?) share buss bars IIRC.  A few times I have just had to clean 
the springs or resolder the buss bas joints.  The springs also tend to 
come loose sometimes.  I would suggest to check the joints of the buss 
bars on the contact board.  Despite the typical Ensoniq servicing 
issues, the ESQ-1 is a pretty fun synthesizer.  

Richard Moore

----- Original Message -----
From: Rainer Buchty <rainer at buchty.net>
Date: Tuesday, May 31, 2005 3:56 am
Subject: Re: [sdiy] My new ESQ-1

> Tim,
> 
> >Just scored an ESQ-1 for $50 at a used music equipment store! Its 
> only>problem is that one ovtave of the keyboard is dead.
> 
> An octave or "just" a block of 8 keys? If it's nothing more or 
> less 
> mechanical, i.e. the keyboard itself, keyboard PCB, or diodes, the 
> only 
> remaining failure is the keyboard processor -- which seems to die 
> quite 
> often on the ESQ1.
> 
> >The MIDI in is just fine however, so the dead keyboard is not a
> >terribly big problem. You know the sad thing? Looks to me like this
> >unit STILL has the factory patches in it!
> 
> What OS version does it run? (Hold down REC and press MASTER.) The 
> latest is OS3.5 which also contains factory presets, any prior OS 
> requires you to load factory presets from tape or via MIDI.
> 
> >Anyway, it makes some great electronic / ambient sounds (not so 
> hot at
> >imitative, despite the fact that the factory sounds try to 
> emphasize this).
> >If anyone has links for good ESQ-1 info / mods / schemos or 
> sounds, I'd
> >appreciate it. 
> 
> Shameless self-advertising follows:
>    http://www.buchty.net/ensoniq
> 
> Also includes customization for your ESQ1 OS such as including own 
> "factory" presets, changing default settings etc.
> 
> >Also, I'm thinking that the ESQ's voice architecture might be worth
> >studying/replicating with a couple of AVRs. A one-voice ESQ would 
> be a nifty
> >(and realizable) micro-based project. Or so I think. :)
> 
> See http://www.buchty.net/ensoniq/files/ics1261.pdf for sound chip 
> details.
> 
> Each oscillator is basically a 24-bit phase accu with 16-bit 
> incrementum plus some bit-shifting / bit-stencil circuitry for 
> proper 
> wave address selection. I doubt, that a single AVR is able to 
> supply 
> more than the 3 required oscillators per voice with the required 
> ~38kHz 
> (8MHz/(8*(24+2))) update rate per osc.
> 
> Rainer
> 
>