78 RPM-BELL TELEPHONE LAB-TEST & EXPERIMENTAL RECORDINGS-SET OF 8-VICTOR-(RARE)

$

250

THIS IS AN EIGHT RECORD SET OF TECHNICAL AND EXPERIMENTAL RECORDS RECORDED AT THE BELL TELEPHONE LABORATORIES IN NEW YORK. EACH MARKED NOT FOR SALE.

EACH RECORD IS DOUBLE SIDED. RECORD BTL-6 IS SINGLE SIDED.

RECORDS 1, 2, 3 APPEAR TO BE ELECTRICALLY RECORDED, THE REST ACOUSTIC REGARDLESS OF THE LABELS.

EACH RECORD IS INTRODUCED AND EXPLAINED.

DISC IA. MUSIC.   HAS 7 BANDS.  EACH HAS A DIFFERENT DEGREE OF FREQUENCY SUPPRESSION.

DISC 2B. SPEECH.  SAME AS ABOVE.

DISC 2A. MUSIC AND SPEECH SAME AS ABOVE. PLUS AMPLIFIER OVERLOAD.

DISC 2B. MUSIC AND SPEECH. SAME AS ABOVE. NO OVERLOAD.

DISC 3A. MUSIC. 7 BANDS WITH DIFFERENT TRANSMISSION UNITS.

DISC 3B. SPEECH. SAME AS ABOVE.

DISC 4A. MUSIC.  ILLUSTRATES EFFECTS OF ELIMINATING HIGHER FREQUENCIES FROM PIANO, CELLO, FRENCH HORN BY USE OF LOW PASS FILTER.

DISC 4B.  MUSIC . SAME AS ABOVE ONLY LOWER FREQUENCIES WITH HIGH PASS FILTER.

DISC 5A.  VOCAL TONES. ILLUSTRATING CERTAIN PHENOMEMA IN THE RECOGNITION OF THE PITCH OF MUSICAL TONES.

DISC 5B. INSTRUMENTAL TONES. SAME AS ABOVE.

DISC 6A. ILLUSTRATION OF PHASE DISTORTION IN SPEECH.

DISC 7A. MEASURING NOISE.

DISC 7B. SAME AS ABOVE

DISC 8A.  ACOUSTIC REFLECTIONS OF SPEECH AND MUSIC.

DISC 8B. SAME AS ABOVE.

THESE ARE 12" RECORDS

THIS IS CERTAINLY AN UNUSUAL AND RARE GROUP OF RECORDS.

CONDITION :    E- OR BETTER

POLICIES: WE GRADE 78'S THE WAY THEY ARE GRADED IN THE PREMIUM RECORD GUIDE BY LES DOCKS. WE GRADE  45 RPM AND 33 RPM RECORDS AS THEY ARE GRADED IN GOLDMINE PUBLICATIONS. WE SHIP 78'S IN  CARDBOARD SANDWICHES IN OVERSIZED BOXES WITH PLENTY OF PEANUTS . 45'S AND 33'S ARE SANDWICHED AND SHIPPED IN STANDARD STURDY RECORD BOXES. WE COMBINE SHIPPING ON MULTIPLE ORDERS. FOR EXAMPLE : IN THE U.S. WE WILL SHIP UP TO 10 78'S FOR THE PRICE OF ONE. AFTER THAT WE WILL CHARGE AN ADDITIONAL HANDLING CHARGE. OUR NORMAL HANDLING CHARGE IS $2.50. WE SHIP BY MEDIA MAIL UNLESS SPECIFIED OTHERWISE . OUTSIDE OF THE U.S. SHIPPING IS BY WEIGHT ONLY, SO MULTIPLE ORDERS ARE LESS EXPENSIVE ON A PER RECORD BASIS. WE SHIP FOREIGN SALES VIA FIRST CLASS INTERNATIONAL UP TO 4 POUNDS. AFTER 4 POUNDS WE MUST SHIP PRIORITY. WE WILL NOT ADJUST VALUES FOR CUSTOMS OR INSURANCE PURPOSES. WE HAVE A 14 DAY MONEY BACK RETURN POLICY AS SHOWN BY E-BAY. WE STRIVE FOR HONEST GRADING, SAFE PACKAGING AND QUICK HANDLING. WE WILL GIVE FEEDBACK. IF YOU DO HAVE A LEGITIMATE PROBLEM PLEASE CONTACT US. WE WILL TRY TO WORK IT OUT. THANKS FOR YOUR INTEREST IN OUR ITEMS.