[sdiy] Anyone ever build a sampler?

[John L Marshall]

Glen,

I apologize for twisting the thread. I didn't mean to rain on your parade.

When you first posted your sampler query, I though your vision was something
as elaborate as the many commercial samplers on the market. I will guess at
least two or three person (man) years of work are required to develop.
Skills in analog, digital and software engineering as well as other
engineering skills are required. Grounding is an art unto its self. I see
many hours and dollars invested before you are rewarded with sounds that are
swimming around in your brain.

Just choosing the optimum A/D converter can be daunting. The current trend
is in specmanship. The A/D must be 24 bit or it doesn't measure up for
marketing. I suspect that there are 20 bit A/D's (maybe even 18 bit) that
outperform the current crop of popular 24 bit A/D's. Twenty four bits sells
and 20 bit doesn't sell. But, I haven't looked at specs lately. A really
good 16 bit A/D in a properly designed circuit in a noise free environment
can yield a dynamic range of 96 dB. Enough for most requirements.

Environment matters. I measured a noise floor of -72 dB for sound blaster
live in one of my computers. Yet in a quite environment a 16 bit A/D should
approach -96 dB noise floor. Computers are really, really noisy.

Harvest some A/D's  from a CD player or sound card and experience the enjoy.

John


----- Original Message -----
From: Glen <mclilith at ezwv.com>
To: <synth-diy at dropmix.xs4all.nl>
Sent: Friday, October 19, 2001 9:05 PM
Subject: Re: [sdiy] Anyone ever build a sampler?


> Well, I've gotten a few direct responses to my question so far, and a lot
of
> tangential chat to go with it.  :)
>
> I was hoping to hear a higher ratio of direct responses, but I guess
building
> gear like this is a bit alien to a lot of the people on this list. I'll
admit
> that it doesn't seem like a trivial task to me, but I'm still interested
in the
> notion. I know that I could buy a sampler (if I had the money), but I'd
like to
> see what I can do on my own. As much as anything else, I want the
experience of
> actually creating something myself. One of the reasons that a sample-based
> instrument seems interesting to me, is that it seems to be a fairly
unusual
> personal project.
>
> A couple people on this list mentioned building simple EPROM based 8-bit
sample
> playback modules. I consider this to be a good start, and it is indeed a
device
> that employs sampling technology to synthesize a musical sound, so it is
almost
> a sampler. It just doesn't record its own samples. I'll probably aim for
> building something like this, to start out. I don't even mind if my
initial
> testing is done with my PC as a controller for my external sample player.
> Eventually, I'll need some sort of embedded control for any serious
project,
> but that can come later. I'm still learning and exploring at the moment.
>
> A friend of mine gave me a broken Ensoniq Mirage, and I'm fixing it up.
After
> working with that unit awhile, I developed an itch to hack it into
something
> more than it is. Like anyone who has ever used a Mirage, I've dreamed of
> expanding the memory and disk storage options, but no matter what cool
fantasy
> hack I thought of, I ended up reminding myself that the Mirage is only a
> single-channel, 8-bit sampler. Do I really want to put a lot of effort
into
> making a "SuperMirage" when I would have to scrap nearly everything about
the
> unit to make it sound as nice as I'd like it to?
>
> That's when I started wondering about making some original sample-based
> hardware of my own. However, if I make my own gear, I'd really like to
graduate
> to 16 bit sound. Does anyone have any ideas or sources for obtaining cheap
> 16-bit A-D or D-A convertors? Possibly chips taken from old sound cards or
> broken CD players? Does anyone know a source for new parts that can be
> purchased in single-unit quantity, at reasonable prices?
>
>
> Later,
> Glen