background image

REPLACING FUSES & METER LAMPS

Changing the fuse is easy and can be done without any tools and while the DVC is still in a rack.
1) Disconnect the IEC AC mains for safety
2) Rotate the fuse cap anti-clockwise 1/4 turn
3) Remove the fuse and replace it with a new 1 AMP, 250 VOLT, AGC1 type fuse
4) Reconnect the IEC AC mains, turn on the power and meter lamps should once again glow.

If the new fuse also blows, it means there is probably a problem in the Dual Vocal Combo that needs fixing.
Fuses are meant to blow in those situations to protect against further damage including fire and the unpleasant
smell of transformer meltdown. The DVC will need to be sent to the dealer or factory for service.

Changing the meter lamps is pretty easy. These are simple incandescent bulbs chosen for long life but
eventually they will fail. They are always available from Manley Labs but most electronic stores will also have
them (Radio Shack part number 272-1143) and are described as "Midget Screw-Base Lamps",  12 Volts @ 75
mA.

1) Disconnect the IEC AC mains for safety
2) Remove the two small Phillips head screws located at the back which hold the perforated top cover in place.
Slide the cover towards the back to remove it.
A) Locate the meters at the front panel and the two brass nuts on the back which holds a small printed circuit
board to the back of the meters. These are 3/32 nuts which must be loosened and removed to gain access to the
bulbs. The small board should slide back and will present the bulb in its socket.
B) Unscrew the light bulbs anti-clockwise (how many ________ does it take to unscrew a light bulb?) and
screw in the new ones clockwise.
C) Replace the small printed circuit board to the back of the meters and re-attach the small brass nuts. These
should be reasonably tight for good electrical contact but not forced to the point that the meter is damaged or
the small screws on the meter become stripped.
D) Replace the top cover and the two screws that hold it in place, then re-connect the IEC AC mains plug and
turn on the power to check out the new bulbs.

There are no other parts expected to age that are user servicable. Electrolytic Capacitors should probably be
replaced after 10 years in audio gear and some say ICs, transistors and pots should be replaced in 20 years to
keep the unit in optimum condition. This is a general guide for audio gear that is intended to be used for
decades. On the other hand, you can expect to throw away most digital gear after 5 years because in 3 years
new stuff does 10 times more and costs 10 times less. Funny how that stuff ages and fine analog keeps being
used for decades. In 1999 64 megs of memory costs about $100 and is 8 chips on 1 module. In 1974 it took
150,000 chips and cost $3 million bucks and now its worth is nothing. Good Analog is a long term thing.

1

2

A

B

16

Содержание Langevin Dual Vocal Combo

Страница 1: ...RIES INC OWNER S MANUAL LANGEVIN DUAL VOCAL COMBO MANUFACTURED BY MANLEY LABORATORIES INC 13880 MAGNOLIA AVE CHINO CA 91710 USA TEL 909 627 4256 FAX 909 628 2482 email emanley manleylabs com http www...

Страница 2: ...EAMPLIFIER 8 9 OPERATION NOTES 10 11 SPECIFICATIONS 12 TROUBLESHOOTING 13 14 INTERNAL ADJUSTMENTS 15 REPLACING FUSES AND METER LAMPS 16 MAINS CONNECTIONS 17 WARRANTY 18 WARRANTY REGISTRATION 19 APPEND...

Страница 3: ...ntials for half the price The Combo is 100 discrete transistor in the signal path and there are no op amps except to drive the LEDs in the Opto circuit and the Meter circuit Negative feedback is minim...

Страница 4: ...s intended as a safe smooth basic tone control and not as a comprehensive do everything EQ but is very effective at compensating for the proximity effect from Cardioid pattern mics D EQ IN EQ OUT EQ O...

Страница 5: ...he gain will rise that 10 or 12 dB along with headphone leakage air conditioning rumble throat noises etc Don t forget that if you are like many engineers you will be limiting the vocal again in the m...

Страница 6: ...e going signal C BALANCED LINE OUT This is the final output after the Mic Pre EQ and Opto Limiter It is ONLY meant to drive balanced inputs If one uses this XLR to connect to an unbalanced input expec...

Страница 7: ...image Most solid state circuits use a large amont of negative feedback to lower noise and distortion at the cost of transient accuracy This preamplifier started out clean and quiet so minimal negative...

Страница 8: ...or mic patches This is a good idea with phantom on or off Consider a variation of this any mic connection just a little bit bad will be extra noisy with phantom turned on This goes for cables patchbay...

Страница 9: ...from the guitar can lose highs so it may be worth having a low capacitance 10 foot cable on hand On the wiring PIN OUTS you may have noticed we specified CIRCUIT GROUND rather than just GROUND We have...

Страница 10: ...to use our Langevin line amplifier circuit which we also use in the Langevin Enhanced Pultec Equalizers rather than copy UREI designs because frankly our circuit sounds better and cleaner Back to this...

Страница 11: ...e desirable tone of the drum is diminished If used gently this can be applied to brighten up the attack of the drum but it is difficult to apply in practice because drums can be very dynamic One great...

Страница 12: ...40 dB range 15 dB Limiter Maximum Limitting 20 dB 11 dB w 4 sine Attack Time fixed 20 mS Release Time fixed 500 mS Input Impedance 2400 Ohm transformer coupled optimised for mics with 100 to 600 ohm...

Страница 13: ...time to time feed unbalanced inputs Insert a 1 4 mono tip sleeve plug unwired into the unbalanced output This makes the levels right You could leave this plug in permanently but we don t recommend it...

Страница 14: ...the workstation Even a 6 level from their system pegs the meters Some of you know already what s going on That 6 level is referenced to digital full scale and the computer might have 18 or 18 5 or 20...

Страница 15: ...ust for 0 VU on the Meters 6 7 This adjusts the meter zero for Reduction mode Meter switches to REDUCTION Adjust for 0 VU on the Meters 8 9 This adjusts the meter in Reduction mode to reflect the actu...

Страница 16: ...cuit board to the back of the meters These are 3 32 nuts which must be loosened and removed to gain access to the bulbs The small board should slide back and will present the bulb in its socket B Unsc...

Страница 17: ...al requirements If your unit does not have a plug fitted the coloured wires should be connected to the appropriate plug terminals in accordance with the following code GREEN YELLOW EARTH terminal BLUE...

Страница 18: ...a Manley Laboratories product fails to meet the above warranty then the purchaser s sole remedy shall be to return the product to Manley Laboratories where the defect will be repaired without charge f...

Страница 19: ...ranty and registration Thank you again for choosing to use Manley Laboratories MODEL ____________________ SERIAL No ______________________ PURCHASE DATE ______________ SUPPLIER ______________________...

Страница 20: ...CTION REDUCTION OUTPUT OUTPUT METER METER REDUCTION REDUCTION REDUCTION REDUCTION GAIN GAIN LINK LINK SEP SEP INPUT INPUT DIRECT DIRECT INPUT INPUT DIRECT DIRECT by Manley Laboratories Inc by Manley L...

Отзывы: