TEAC AN-60 - noise reduction unit

[zackk]

How much of an effect should the noise reduction have on the signal passing through?
I know there are different DBX encodes so I wasn't sure.
On my Teac X-2000r, DBX is night and day, on this AN-60, I hear no change when dolby is in circuit.

Also... Can anyone hook me up with a Service manual?

 

[danj]

Properly calibrated, about -9dB noise reduction.
This is a Dolby "B" unit and operates very differently from a DBX unit. There are many sources on the net which explain how a Dolby "B" circuit works.

AudioEngine has the operators manual for the AN-60. I've not seen a service manual. The manual will tell you how to calibrate. When I fixed the dead channel of my AN-60 I had to use basic troubleshooting skills to find the problem. The first thing I would do is spray all of the switches and pots (under the knobs) with DeOxit.


Listen with good headphones and you should hear a difference.

 

[zackk]

Thanks for the info. I cleaned the controls and recapped this unit. Still got a channel out.

So when I hit the Dolby switch to "IN" should I hear the signal change?

 

[oldvinyldude]

Even with only 1 channel working, yes you should be able to hear a difference. Zero out the level on the non working channel for this test.

Record with a source program (LP, another tape, CD) that has consistent treble content.

During the recording, switch Dolby in and out every 5 seconds for perhaps a minute total recording.

Upon playback, you should hear a definite difference in high frequency. Leave Dolby out for this playback test.

If you really cant hear any difference, then something is wrong with the unit, or you are not switching on encoding during recording somehow.

 

[zackk]

Can't I test it by ear just by monitoring signal through the unit and toggling the switch? I don't have to actually record a tape to test it do I? That would mean you can only record in Dolby but not playback... so That wouldn't make sense, and is why I haven't tried recording to tape to test. Sorry if this is confusing....

I have signal from my DAC going in to the unit (through the confusingly, but at the same time not confusingly labelled "TO TAPE DECK LINE OUT") and then signal going out to my amp (To Amplifier Tape Mon).

 

[oldvinyldude]

Can't I test it by ear just by monitoring signal through the unit and toggling the switch? I don't have to actually record a tape to test it do I? That would mean you can only record in Dolby but not playback... so That wouldn't make sense, and is why I haven't tried recording to tape to test. Sorry if this is confusing....

Yes you can record and monitor while switching the Dolby in and out. I suggested this other methodology to remove any switching distraction on playback-only have to listen for difference.

I have signal from my DAC going in to the unit (through the confusingly, but at the same time not confusingly labelled "TO TAPE DECK LINE OUT") and then signal going out to my amp (To Amplifier Tape Mon).

This seems right, but I get confused at times. Fortunately, working with small signal levels-if you have something patched incorrectly, it simply does not give the desired result, and no damage occurs. Double check the NR Operators manual.