The owner's manual/operating instructions that I purchased was the original factory document and it was in at least three and maybe more languages. I no longer have it because I sold the tape recorder and included the owner's manual/operating instructions and a service/repair manual that I bought on ebay for the new owner.
Turns out this was not the manual i was looking for. The concertmate 670 keyboard i have is a "Realistic" model made for Radio Shack and none of the diagrams on the owners manual i received matches up. HOWEVER, I must say the service Owners Manual provides was fast and efficient by being available online. The manual was in good readable condition and easily downloaded.
Great price, Quick delivery, the document was very usefull A+++++++++++++++
Text excerpt from page 41 (click to view)
Bass Adjustment (BASS)
ENGLISH ESPA�OL DEUTSCH FRAN�AIS ITALIANO NEDERLANDS
You can adjust the cut-off frequency and the Bass level. In �FRT1� mode, bass adjustment affects only the rear output: front output cannot be adjusted.
1. Press the AUDIO button and select the Bass mode (BASS) in the Audio Menu. 2. Select the desired frequency with the 2/3 buttons.
40 � 63 � 100 � 160 (Hz)
3. Boost or attenuate the bass level with the 5/� buttons.
The display shows �+6� � ��6�.
Treble Adjustment (TRE)
You can adjust the cut-off frequency and the Treble level. In �FRT1� and �FRT2� modes, treble adjustment affects only the front output: rear output cannot be adjusted.
1. Press the AUDIO button and select the Treble mode (TRE) in the Audio Menu. 2. Select the desired frequency with the 2/3 buttons.
2K � 4K � 6K � 10K (Hz)
3. Boost or attenuate the treble level with the 5/� buttons.
The display shows �+6� � ��6�.
