OBERHEIM SYNTH

In addition to liking a hot signal, it also likes nice sharp square wave data.
If the heads on the cassette aren't clean and/or in good condition, there may be difficulties.
If the azimuth is out by just a small amount, the waveform really rounds off.
There is a clipping circuit in a timecode reshaper that fixes these problems. 
I used the Otari reader/re-shaper, but almost anything that purports to recondition ( not regenerate) timecode will do.
I suspect a cheap fuzzbox will do too, but have a listen to what the data sounds like coming off the cassette, it shouldn't be dull sounding.
Typically there are some thumps and a chattering along with a tone.
Each of the Oberheim devices from this era have a distinctive sound, once you've heard it a few times, you can tell which is which.
A comparison can be made by attempting a cassette dump from the front panel. 
The tone and chattering will be full on bright, and a cassette recording should be slightly duller, but not dramatically duller.

Another issue can be a data inversion.
Until I standardized which cable and cassette machine I used, the backup and restore detail was a bit hit and miss.

Still another issue is the mono/stereo quandry.
My technique was to record both channels and then play from only one of them, leaving a spare track in case of dropout (poor tape to head contact for a moment).
Also a second pass was made immediately after the first in case of physical damage to the playing surface, tape breakage and repair etc.

.Interestingly,after a restore, patch A1 will be whatever was in there before the restore until you press "A" "1" to load the tape's patch A1.

Good luck with your quest

--- On Thu, 9/5/13, 65 Lotus <Lotus@...> wrote:

From: 65 Lotus <Lotus@...>
Subject: Re: [oberheim] Re: OB-Xa problem loading factory presets
To: oberheim@yahoogroups.com
Date: Thursday, 9 May, 2013, 17:47
















 



  


    
      
      
      And as alluded to before, it likes a hot signal.