Oakley ADR30 User Manual Download Page 9

GAIN1

 This adjusts the signal volume that comes out of BBD2 which is the BBD we are 

listening to when the ADR30 is in short mode.

Set the range switch to short, and set the delay time pot to its central position. Input a 220Hz 
triangle wave or sawtooth wave into the ADR30. Adjust the input level so that the red PEAK 
LED is just lit.

Connect your scope probe to pin 7 of U16. Adjust GAIN1 so that the signal seen here is the 
same amplitude (ie. the peak to peak voltage) irrespective of whether the front panel's Balance
control is either at one end or the other. In other words, adjusting GAIN1 makes the wet 
signal to be the same size as the dry signal. You will notice that the wet signal is not quite the 
same shape as the dry signal as it has had a long and tortuous journey to get here.

GAIN2

 This should be done only after GAIN1 has been correctly set. Connect your scope 

probe to pin 7 of U16. Adjust GAIN2 so that the signal seen here is the same amplitude (ie. 
the peak to peak voltage) irrespective of the position of the range switch. In other words, you 
should adjust GAIN2 so that there is no volume change when listening to the wet signal when 
the range switch is changed.

BAL

 This trimmer adjusts the amount of high frequency clock breakthrough into the audio 

output of the final BBD. You want to set this so that the smallest amount of clock is getting 
through to the output.

Set your scope's input to AC, the time base to 5uS per division and the scaling to 500mV per 
division. Turn the input level down on the ADR30 so that no signal is passing through the 
delay lines. Set the delay time control to its middle position. Connect your probe to the emitter
of Q7, which is the right hand pin when the ADR30's pots are facing you.

Adjust the BAL trimmer so that the waveform amplitude seen on the scope trace is minimised.
Set incorrectly you'll see a kind of spiky square wave. Set correctly the trace will reduce to 
just a series of spikes.

FBK 

This adjusts the maximum amount of feedback available from the feedback control knob.

This one is set to taste and it can be set to allow no self-oscillation at all or at the other end to 
allow self-oscillation readily. I set mine so that self-oscillation only occurs when the feedback 
pot is beyond the 3 o'clock mark.

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Summary of Contents for ADR30

Page 1: ...Oakley Sound Systems Analogue Delay ADR30 User Manual V1 3 Tony Allgood Oakley Sound Systems CARLISLE United Kingdom...

Page 2: ...ard please visit the main project webpage at http www oakleysound com ADR30 htm For general information regarding where to get parts and suggested part numbers please see our useful Parts Guide at the...

Page 3: ...nal levels at optimum ensuring a respectable signal to noise ratio without clipping The unit will not be damaged by driving the unit into overdrive and interesting sounds can be obtained by deliberate...

Page 4: ...r to be being sent to the BBDs to reduce the likelihood of overdriving the BBDs and to improve overall signal to noise ratio The signal meter is monitoring the signal after it has been compressed so t...

Page 5: ...N3005 devices while SHORT selects just the one For chorus and flanger type effects which require only small delays then the short setting is to be used As the signal pathway through a BBD is long and...

Page 6: ...o output sockets One carries the delayed signal that has passed through the delay lines and all the associated circuitry like the companders and anti aliasing filters The other the main output is the...

Page 7: ...rk well with signal levels direct from a mixer line level synthesisers and modular synthesisers The input impedance is too low to work direct from guitars unless they are fitted with internal pre ampl...

Page 8: ...just the time base of the scope to 500ns division so that you can measure the width of the pulses Adjust WIDTH so that the width of the pulse at 5V is approximately 1 2us OFF2 OFF1 These adjust the bi...

Page 9: ...tch In other words you should adjust GAIN2 so that there is no volume change when listening to the wet signal when the range switch is changed BAL This trimmer adjusts the amount of high frequency clo...

Page 10: ...f support is the Oakley Sound Forum at Muffwiggler com If you have a comment about this user manual or have a found a mistake in it then please do let me know either via e mail or the forum Tony Allgo...

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