[sdiy] midi to cvand gate , negative output? good idea ?

[Magnus Danielson]

From: Peter B <dragonservicing at success4business.com>
Subject: [sdiy] midi to cvand gate , negative output? good idea ?
Date: Thu, 10 Jan 2002 23:40:32 +0000

> Hi,

Hi Peter,

> just wondered if people thought having the ability to houtput a negative
> voltage on a Midi to cv unit was a good idea ?
> I recently was calibrating a Roland piece of gear that was being used
> with a kenton unit,and I was suprised when I found that when I selected
> the lowest note on the controlling keyboard I got -1 volt out from the
> kenton.[on the control volt output]
> I know that some Midi to cv units won't output such large negative
> signals ,and was just wondering if it was possible that some synths
> would only accept positive signals .

It comes down to the CV summing and what offset you have. The ASM-1
(which in this case is very similiar to many, many other VCO/VCFs in
the sence of CV summing) handles negatives just the right way, and so
I expect most synths to do.

You will notice when the input summing "clips" since you don't get any
further. There are other limits as well (such as current saturation in
the expo-output transistor).

Toss it decent sized (say +10 to -10 V) volagtages and learn how far
you can take the ride.

Cheers,
Magnus