- DL manuals
- D.W. Fearn
- Music Equipment
- VT-F
- Operating Instructions Manual
D.W. Fearn VT-F Operating Instructions Manual
Summary of VT-F
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Vt-i/f vacuum tube instrument interface d.W. Fearn operating instructions.
Page 2: How to Contact Us:
How to contact us: telephone: 610-793-2526 fax: 610-793-1479 mail: p.O. Box 57, pocopson, pa 19366 u.S.A. Shipping address: 182 bragg hill road west chester, pa 19382 u.S.A. E-mail: dwfearn@dwfearn.Com world wide web: http://www.Dwfearn.Com.
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T a b l e o f c o n t e n t s history of the vt-i/f .............................................................................. 7 specifications.......................................................................................... 9 description....................................................
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N o t i c e d.W. Fearn shall not be liable for technical or editorial errors or omissions in this manual, nor for incidental or consequential damages resulting from the use of this material. This instruction manual contains information protected by copyright. No part of this guide may be photocopied...
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L i m i t e d 5 -y e a r wa r r a n t y during the warranty period, d.W. Fearn will, at no additional charge, repair or replace defective parts with new parts. This warranty does not extend to any vt-i/f that has been damaged or rendered defective as a result of accident, misuse, or abuse; by the us...
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7 h i s t o r y o f t h e v t - i / f va c u u m t u b e i n s t r u m e n t i n t e r f a c e as far back as i can remember, taking instruments “direct” has never sounded very good to me. There always seemed to be a lack of dynamics, and a sterile qual- ity to sounds recorded with a direct box (or ...
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Vt-i/f vacuum tube instrument interface d.W. Fearn 8 i have seen how direct boxes can be abused in the studio environment, so the vt-i/f was built to take rough treatment. The case is machined from solid quar- ter-inch thick aluminum plate, and finished with a tough polyurethane aircraft fin- ish. W...
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D.W. Fearn vt-i/f vacuum tube instrument interface 9 s p e c i f i c a t i o n s (with 200 mv input) input 200 mv nominal unbalanced input load impedance 1 megohm minimum minimum input level 5 mv nominal maximum input level 2.3 volts p-p for 1% thd gain -10 db frequency response +/- 0.2 db 10 cps to...
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Vt-i/f vacuum tube instrument interface d.W. Fearn 10
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D.W. Fearn vt-i/f vacuum tube instrument interface 11 d e s c r i p t i o n the d.W. Fearn model vt-i/f vacuum tube instrument interface is designed to provide recording professionals with a sonically superior method for recording electric and electronic musical instruments by direct injection (di)....
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13 i n s t a l l a t i o n the vt-i/f is carefully packed for shipment and should survive all but the most brutal handling. If there is any damage, keep the shipping material for use during any claim for damage with the shipper. Included in the box: 1) the vt-i/f instrument interface 2) line cord 3)...
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Vt-i/f vacuum tube instrument interface d.W. Fearn 14 rear panel connections (see figure 1) ac (mains) power (2) the vt-i/f is designed to operate from 100, 120, or 220 volt, 50/60 hz power. The unit will be shipped wired for the voltage specified in the order, but may be changed in the field if nec...
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D.W. Fearn vt-i/f vacuum tube instrument interface 15 front panel connections (see figure 2) the vt-i/f has two identical channels, labeled a and b. They may be used indi- vidually or simultaneously. These instructions apply to either channel. The musical instrument output connects to the vt-i/f ins...
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Vt-i/f vacuum tube instrument interface d.W. Fearn 16 the output connectors (4) are xlr-3 male wired according to aes standard: pin 1 is ground (shield), pin 2 is “high” or “+,” and pin 3 is “low” or “-.” the out- put is transformer-balanced. The output level is a nominal -30 dbm. This is some- what...
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17 o p e r at i o n rear panel controls (see figure 1, page 14) power switch (1) primary power is applied to the vt-i/f circuits when the power switch (1) is in the up position. The amber pilot lamp (5) on the front panel indicates that the unit is on. It takes about twenty seconds for the interface...
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Vt-i/f vacuum tube instrument interface d.W. Fearn 18 ronment. Experiment with the orientation of the instrument to minimize this source of noise. Most guitar and bass players will do this automatically, but with keyboards it may be necessary to rotate and/or move the instrument to find the qui- ete...
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D.W. Fearn vt-i/f vacuum tube instrument interface 19 1. The vt-i/f must be located near the instrument. Ten feet of cable between the instrument and the vt-i/f should be considered the maximum. 2. Use the best quality cables you can. We don’t believe you have to use eso- teric wire, but do use good...
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21 t h e o ry o f o p e r at i o n this circuit description refers to only one channel. Both channels are identical, sharing only the power supply. (see figure 3.) input section the instrument input jack is fed directly to the grid of the first amplifier stage, a selected 6072 or selected 12ay7. The...
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Vt-i/f vacuum tube instrument interface d.W. Fearn 22 tive network on the secondary of the transformer provides proper loading and matching to the input of the external microphone preamplifier. The gnd lift switch disconnects pin 1 of the output connector from the internal ground when the switch is ...
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D.W. Fearn vt-i/f vacuum tube instrument interface 23 m a i n t e n a n c e the vt-i/f is built with only the highest quality parts and will prove to be extremely reliable. Vacuum tubes and electrolytic capacitors, however, have a finite useful life and must be periodically replaced. Top cover remov...
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Vt-i/f vacuum tube instrument interface d.W. Fearn 24 although you could purchase a batch of 12ay7s and select the quietest one(s), it may be cost effective to buy a low-noise tube from the us. Current prices are $35.00 for a selected low-noise 6072/12ay7. We test the tubes in a vt-i/f after a burn-...
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D.W. Fearn vt-i/f vacuum tube instrument interface 25 troubleshooting most problems will be traced to defective vacuum tubes. However, if normal tests do not easily reveal the problem, feel free to call the factory for assistance. If you lack access to a qualified service technician with vacuum tube...