Instruction/ maintenance manual of the product 376 dbx Pro
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® 376 V acuum T ube Channel Strip w/Digital Out User Manual.
WARNING FOR YOUR PROTECTION PLEASE READ THE FOLLOWING: KEEP THESE INSTRUCTIONS HEED ALL WARNINGS FOLLOW ALL INSTRUCTIONS CLEAN ONLY WITH A DAMP CLOTH. DO NOT BLOCK ANY OF THE VENTILATION OPENINGS. INSTALL IN ACCORDANCE WITH THE MANUFACTURERS INSTRUCTIONS.
U.K. MAINS PLUG WARNING A molded mains plug that has been cut off from the cord is unsafe. Discard the mains plug at a suitable disposal facility . NEVER UNDER ANY CIRCUMSTANCES SHOULD YOU INSERT A DAMAGED OR CUT MAINS PLUG INTO A 13 AMP POWER SOCKET.
T able of Contents 376 Intr oduction 0.1 Defining the 376................................................i 0.2 Service Contact Info .........................................ii 0.3 W arranty ............................................................ii 0.
INTRO CUSTOMER SER VICE INFO 376 DEFINED W ARRANTY INFO ® INTRODUCTION 376.
Intr oduction ® 376 User Manual i 376 Congratulations on your purchase of the dbx 376 V acuum Tube Channel Strip with digital capa- bilities. For over 25 years, dbx has been the industry leader in dynamics processing. With the introduction of the 376, the standard for channel strip processors has now been completely redefined.
® Intr oduction 376 376 User Manual If you require technical support, contact dbx Customer Service. Be prepared to accurately describe the problem. Know the serial number of your unit.
Intr oduction ® 376 User Manual iii 376 FOR RACK MOUNT USE ONL Y - Install the 376 in your rack with the provided rack screws. When installed in a rack, the unit should be positioned with enough room (at least one 1U above the and 1U below the unit) to allow proper ventilation.
Getting Started ® Getting Started Section 1 376.
Getting Star ted ® 376 User Manual 2 Section 1 376 P o wer Switch Turns the 376 on and off. IEC P o wer Cor d Receptacle This is the power cord receptacle of the 376.
® Instrument Input This unbalanced high-impedance input connection is used to insert an instrument signal direct- ly into the preamp. Use the LINE switch to make instrument input or the rear panel line input active. Plugging into the instrument jack will override the rear panel 1/4” input jack (line input must be selected).
Getting Star ted ® 376 User Manual 4 Section 1 376 Lo w control This control varies the gain of the low frequency equalization; the gain range is -15 to +15 dB. This filter is a low shelving filter at 80 Hz. Mid contr ol This control varies the gain of the mid frequency equalization; the gain range is -15 to + 15 dB.
® Output Le vel This knob controls the overall level of the output signal, and ranges from -20 to +20dB. Meter Select Switch This switch allows you to select display metering of either the digital or analog output signal. The analog level is scaled in dBu, while the digital level is scaled in dBFS.
Getting Star ted ® 6 Section 1 376.
ANALOG APPLICA TIONS ® ANALOG APPLICA TIONS Section 2 376.
Analog Applications ® 3 376 User Manual 8 Section 2 376 • Turn off all equipment before making any connections. • Install the 376 in your rack with the provided rack screws.
® 3). Turn the 376’s DRIVE control to the minimum position. Turn the OUTPUT LEVEL control to the 12 o’clock position, and apply power to the 376. Make sure your console’s gain fader is at the nominal level and begin to slowly increase the gain of the 376 using the DRIVE control.
Analog Applications ® 376 User Manual 10 Section 2 376 3). Enable the record function of the specific track of the recorder and open the specific tape track return in the console which corresponds to the track to which the 376 is connected.
DIGIT AL APPLICA TIONS ® DIGIT AL APPLICA TIONS Section 3 376.
Dither Switch This switch is used to select the dither type algorithms including: TPDF , SNR 2 , or None. Dither is random noise that is added to the audio signal which effectively eliminates the harmonic dis- tortion created by truncation. See the“T runcation” graph in section D.
AES/EBU Digital Connector T he 376 pr o vi d es AES / EB U di gi t al o ut pu t f or m at t i ng t hr o ugh t he X LR connect or . B e s ur e t o use s ho r t l engt hs of 110 Ω d ig ita l ca b le s ra th e r th a n s ta n d a rd X L R to X L R ca b le s.
Rear P anel Connections • Connect the source to the desired 1/4” TRS or XLR input. • Connect the AES/EBU or S/PDIF output of the 376 and run into the AES/EBU or S/PDIF input interface of the DA W (CPU). Fr ont P anel Digital Output F eatures 1).
Rear P anel Connections • Connect the source to the desired 1/4” TRS or XLR input jack. • Connect the AES/EBU or S/PDIF output of the 376 and run into the AES/EBU or S/PDIF input of the digital mixer . Fr ont P anel Digital Output F eatures 1). Use the METER switch to select digital output metering.
Rear P anel Connections • Connect the source to the desired 1/4” TRS or XLR input. • Connect the AES/EBU or S/PDIF output of the 376 and run into the AES/EBU or S/PDIF input interface of the DA W (CPU). Fr ont P anel Digital Output F eatures 1).
Rear P anel Connections • Connect the source to the desired 1/4” TRS or XLR input jack. • Connect the AES/EBU or S/PDIF output of the 376 and run into the AES/EBU or S/PDIF input of the digital mixer . Fr ont P anel Digital Output F eatures 1). Use the METER switch to select digital output metering.
The 376 gives you the unique option of utilizing the analog and digital outputs simultaneously. This option is ideal for using the analog output section as a reference monitoring signal of the dig- ital signal.
APPENDIX Sync Input Info Block Diagram dbx T ype IV™ White Paper Noise-Shaping Algorithms T runcation Specifications ® APPENDIX Appendix 376.
Appendix A A- Sync Input Info INSTRUCTIONS FOR QUALIFIED SERVICE PERSONNEL: CAUTION : These servicing instructions ar e for use by qualified service personnel only. T o r educe the risk of electric shock, do not per form any servicing other than that contained in the operating instructions unless you are qualified to do so.
Microphone Input +48V Over easy“ Slow 20dB Pad Phase In vert Low Cut dbx TYPE IV Conversion System DSP Dither Sample Rate Wo r d Length Output Format Shape Peak LEDs EQ Clip LED Threshold LED De-Ess.
Appendix C dbx T ype IV™ Con v ersion System White P aper b y Ro ger Johnson The dbx Type IV™ Conversion System is a proprietary analog-to-digital (A/D) conversion process that combines the best attributes of digital conversion and analog recording processes to preserve the essence of the analog signal when it is converted to a digital format.
to-noise perfor mance since the signal is now closer to the noise floor . Because users of digital equipment have to be extremely careful not to exceed 0 dB FS (full-scale), they must use peak-reading headroom meters.
Appendix C Fig. 2 illustrates the mapping function in a different way. Input levels are shown on the left of the graph, while con- verted levels are shown on the right. Notice the mapping of large signal excursions to the 4 dB “Type IV™ Over Region.
Figure 3b - Signal of Fig. 3a Going Beyond the A/D Clip Lev el Amplitude Time A/D Clip Lev el A/D Clip Lev el Figure 3a - Signal Having Low and High F requency Content Amplitude Time Appendix C ® App.
Appendix C Now you’re probably wondering, “What’s the catch? I can’t get something for nothing so what did I give up?” Y ou may be worried that your A/D noise floor got 4 dB worse because we borrowed the top 4 dB of your converter . This is certainly a valid concern.
16-Bit TPDF dither . (a) Shape “off”, (b) with shape set to “S1”, (c) with shape set to “S2.” Parameters: Input -60dBFS, 1 kHz; FFT Length= 2048, Sample Rate= 48 Khz, A verages= 32; Graph Steps= 1024. (a) 24-Bit word, (b) 16-Bit truncated output, no dither .
Appendix D Microphone Input Connec t or: Fe m al e XLR Pi n 2 H ot T y p e : E le c t ro n ica lly b a la n c e d /u n b a la n c e d I m ped anc e: 330 Ω M axi m um I nput Le vel : - 9 dBu or + 11 .
® 8760 South Sandy Pkwy . Sandy , Utah 84070 Phone: (801) 568-7660 F ax: (801) 568-7662 Int’l F ax: (603) 672-4246 Questions or comments? E•mail us at: customer@dbxpro .
An important point after buying a device dbx Pro 376 (or even before the purchase) is to read its user manual. We should do this for several simple reasons:
If you have not bought dbx Pro 376 yet, this is a good time to familiarize yourself with the basic data on the product. First of all view first pages of the manual, you can find above. You should find there the most important technical data dbx Pro 376 - thus you can check whether the hardware meets your expectations. When delving into next pages of the user manual, dbx Pro 376 you will learn all the available features of the product, as well as information on its operation. The information that you get dbx Pro 376 will certainly help you make a decision on the purchase.
If you already are a holder of dbx Pro 376, but have not read the manual yet, you should do it for the reasons described above. You will learn then if you properly used the available features, and whether you have not made any mistakes, which can shorten the lifetime dbx Pro 376.
However, one of the most important roles played by the user manual is to help in solving problems with dbx Pro 376. Almost always you will find there Troubleshooting, which are the most frequently occurring failures and malfunctions of the device dbx Pro 376 along with tips on how to solve them. Even if you fail to solve the problem, the manual will show you a further procedure – contact to the customer service center or the nearest service center
