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DAVID IV 

 

FM Audio Broadcast Processor 

 Installation & User Guide 

 

 

www.inovonicsbroadcast.com 

Summary of Contents for 719

Page 1: ...DAVID IV FM Audio Broadcast Processor Installation User Guide www inovonicsbroadcast com ...

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Page 3: ...3 Software Rev 3 Inovonics Inc 5805 Highway 9 Felton CA 95018 Tel 831 458 0552 Fax 831 458 0554 Register online at www inovonicsbroadcast com PRODUCT REGISTRATION RECORD Model 719 Serial No _______________ Purchase Date _____________________ Warranty Registered Mail Web Reg Date __________ By ____________ ...

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Page 5: ...n Setup Using the Software UNPACKING AND INSPECTION 10 MOUNTING 11 Rack Requirement Heat Dissipation AC MAINS POWER 11 Mains Voltage Selector Mains Fuse Power Cord RADIO FREQUENCY INTERFERENCE RFI 11 Location Ground Loops PROGRAM LINE INPUTS 12 AES Digital Input Analog Line Inputs Unbalanced Operation PROGRAM LINE OUTPUTS 13 AES Digital Line Output Analog Line Outputs Unbalanced Operation COMPOSIT...

Page 6: ...D IV Gain Structure SELECTING THE INPUT 18 SETTING INPUT GAIN 19 Importance of AGC Action Using Test Tones or Not Adjusting Input Gain THE HIGH PASS FILTER 21 OPTIMIZING WINDOWED AGC ACTION 22 Defeating the AGC AGC Maximum Gain Windowing and the AGC Correction Rate STEREO ENHANCEMENT 23 Stereo Width Solo Width THE FIVE BAND MULTIPRESSOR 24 Compressor Drive Spectral Loading Band Coupling PROGRAM EQ...

Page 7: ... Output Normalized Flat FM Output Output Level Controls Sample Rate Converter FRONT PANEL HEADPHONE JACK 40 COMPOSITE MULTIPLEX OUTPUT 40 Confirming Pre Emphasis Mono Mode and Pilot Injection Adjusting the Multiplex Outputs Multiplex Output Servo RDS SETUP 42 PROCESSING PRESETS 43 Factory Presets Creating Custom Presets What am I listening to Deleting Presets Exporting and Importing Presets PROOF ...

Page 8: ...TWARE GENERAL 54 INSTALLING THE SOFTWARE 54 Confirming a Network Connection Running the Software REMOTE CONTROL OF THE DAVID IV 57 Presets Processing Setup Admin Software Sliders PROFILE AND PRESET FILE MANAGEMENT 60 Saving a Profile Saving a Preset Importing a Preset Section VI UPDATING DAVID IV FIRMWARE THE FIRMWARE UPDATER 63 Warning Firmware Update Files Running the Firmware Updater Aborting a...

Page 9: ...ts Features Leading features of the Inovonics DAVID IV A dual slope windowed AGC automatically corrects wandering levels from the console or playout system maintaining long term consistency between diverse pro gram sources without altering the intended tonal balance 5 bands of dynamic range compression and equalization help create a sonic signature tailored to the station s format and personality ...

Page 10: ...unctions intentionally upset the tonal bal ance static and dynamic frequency response and the waveshape native distortion inher ent in all program material Thus it has be come customary to establish and publish performance specifications with audio pro cessing features disabled or bypassed Un less otherwise expressed or implied herein this is the case with figures shown here as indeed seems also t...

Page 11: ... 75 ohms Pre emphasis may be set to 75µs 50µs or OFF Pag es 13 40 RDS Input Unbalanced bridging BNC input ac cepts a 57kHz RDS subcarrier at any level between 0 5V p p and 5 0V p p for a typical injection level of 5 of total carrier modulation Pages 14 41 19kHz RDS Sync When RDS is enabled the Sync Output BNC delivers a 5V p p TTL compatible square wave at the 19kHz pilot fre quency 75 ohm source ...

Page 12: ... USER INTERFACE Front Panel A front panel graphic display and jog wheel allow easy menu guided in situ setup and operation of the DAVID IV LED bar displays indicate in out levels and audio processing ac tion Page 16 Software Control The IP network port and supplied soft ware allow remote setup and operation of the DAVID IV over a local network or the Internet using any Windows PC XP or later Page ...

Page 13: ...SS CHARACTER AUGMENTATION BASS EFFECTS FILTER BAND RECOMBINING BROADBAND LIMITER STEREO GENERATOR DE EMPH COMPOSITE CLIPPER COMPOSITE COMBINER AUTO SERVO PILOT BYPASS SWITCHING AND LEVEL RDS INPUT RDS SYNC MPX OUT 1 MPX OUT 2 DIGITAL LINE OUT ANALOG LINE OUT ADAPTIVE PRE EMPHASIS OPTIONAL DIVERSITY DELAY PHONES MONITOR MPX POWER CONTROL TONE GEN SWITCHING AND LEVEL ...

Page 14: ...networking the DAVID IV UNPACKING AND INSPECTION As soon as the equipment is received inspect carefully for any shipping damage If damage is found or suspected notify the carrier at once and then contact Inovonics We recommend retaining the original shipping carton and pack ing materials for return or transshipment If returned for War ranty repair shipping damage sustained as a result of improper ...

Page 15: ... unit A clearly marked slide switch is directly behind the AC mains connector on the circuit board Use a small screwdriver to set the switch for 115V or 230V operation Mains Fuse It is important to install the appropriate fuse as noted on the rear panel next to the fuseholder A for 115V mains A for 230V operation Fuses are the GMA S500 type 5mm X 20mm size fast blow Power Cord The detachable IEC t...

Page 16: ...t and right channel ANALOG INPUTS with female XLR connectors These are bridging high impedance inputs They do not pro vide termination for the console or other equipment that feeds the DAVID IV Here s why With few exceptions audio line impedance matching is ridi culed by today s hip broadcasters you and erudite equipment manufacturers us The concept of 600 ohm line matching dates from the age of t...

Page 17: ...V is fed from a digital program source The digital output level shown below the slider control corre sponds to program peaks that have been limited to 100 modu lation The output level may be adjusted between 0dBFS digi tal full scale and 20dBFS Analog Line Outputs Male XLR left and right channel ANALOG OUTPUTS on the rear panel are electronically balanced This means that they are ground referenced...

Page 18: ... This is a 5V p p square wave with a 50 duty cycle in phase with the stereo pilot component of the FM multiplex signal This waveform may be used to synchronize an RDS Radio Data System encoder with the stereo pilot RDS Input The RDS INPUT BNC connector accepts the 57kHz RDS subcar rier for combining with the FM multiplex program signal The p p level of the subcarrier can range from 0 5V to 5V corr...

Page 19: ...l menus and readouts Networking the DAVID IV is covered in Section IV Page 47 and software operation in Sec tion V Page 54 We recommend starting with front panel set up however as this method not only gives the immediate grati fication of a hands on experience but is necessary in any event for initiating network connectivity USER ADJUSTMENT GROUPINGS User adjustments for DAVID IV operation are div...

Page 20: ...eration almost immediately Setup and processing parameters in use previous to the power interruption are reloaded instantly from non volatile memory to the processing core Brownout Detection Although the DAVID IV power supply and digital logic circuits will operate at AC mains voltages down to about 50 of nomi nal the graphic display and LED readouts would fail to give consistent indications at ve...

Page 21: ...ial in the desired injection If you make a mistake for example you might push the jog wheel off center which could also rotate it and bring up the wrong menu simply push the Back button to return to the pre vious menu and try again Menu Timeout and Screensaver Once an adjustment is made you may press the Back button to eventually return to the Main Screen or simply leave any cur rent screen showin...

Page 22: ...urn the jog wheel to dial in the desired frequency or level Frequency pro gramming has ballistic acceleration meaning that the faster you turn the jog wheel the more steps you get per revolution A Brief Note on DAVID IV Gain Structure A 20dB 400Hz test tone applied at the input to the processing stages Pre will bring the AGC to 0dB unity gain 20dB is the nominal internal zero VU reference level at...

Page 23: ...red a processing parameter of the DAVID IV but one that by design does not make an audible contribution to the station s signature sound The sole purpose of the AGC is to normalize levels ahead of the other processing stages with out adding coloration This is possible only with a wideband AGC which should always be the first stage in any comprehen sive audio processing system Multiband AGC is a mi...

Page 24: ... not all these devices have their own response to and provide their own representation of program peak and average levels What s more board operators lend their indi vidual interpretations to what they see assuming that they are even paying attention to meters in the first place Adjusting Input Gain Return to the Setup Audio Input menu Next turn the jog wheel to position the brackets around the Di...

Page 25: ...unwanted subaudible pro gram audio components The term unwanted is the keyword here as mega bass seems a mandatory part of any car audio installation and a big bottom end characterizes the sonic signature or nearly all contemporary music stations Navigate to Processing High Pass Filter Once you have arrived at this menu push the jog wheel to enter the adjustment mode Then as you turn the jog wheel...

Page 26: ... Gain Classical music and jazz are two genres that often have wide level variations that beg to be preserved Pianissimo classical passages and a standup bass solo are two examples In these instances a normal configuration of the AGC stage would slow ly bring up these passages to the 100 modulation point which would not sound right at all The Gain slider is generally kept at 18 0 dB for full AGC ac...

Page 27: ... blink A fast rate with a mid value window might be just the ticket in an aggressive pop music format Even with this setting AGC in the DAVID IV shouldn t alter the perceived dynamics of the program although it will definitely erase long term level varia tions in a hurry Some settings might allow AGC action to be audible in speech during a talk show segment for example but not during musi cal prog...

Page 28: ...undstage or sound field Vocal solos are almost always panned dead center just like the talent mic in the radio studio As Solo Width processing is introduced and increased the cen tered vocalist and on air talent will appear to spread across the soundstage This is illustrated on the graphic display as shown here Just like the Stereo Width con trol the shaded area and number are arbitrary and relati...

Page 29: ...e dynam ics will not even tickle the compressors with no indication of gain reduction or G R in any band as shown on the LEVELING COMP bargraph readouts Advanced all the way to 30 0dB all five bands will probably be dancing down close to the bottom of the bargraph displays A proper setting for this control will probably be somewhere close to the center of this control range The factory default is ...

Page 30: ...t to serve as a compressor that s effec tively variable between five bands and one band Full linking does not actually turn the DAVID IV into a single band unit however as each band is still able to respond inde pendently to program peak energy within that band s range Rather the amount of average compression in bands 2 3 and 4 is integrated over time and used as a platform release value for all f...

Page 31: ...closeness the ef fect that the program source is live and up front High Frequencies above the presence range contribute to the quality of sparkle tinkle and air in the pro gram audio Not surprisingly these are the same bands used for multiband compression The EQ sliders are simply level controls in the outputs of the five bands where the spectrum is recombined Use these EQ sliders to craft the gen...

Page 32: ...u ble just go back and choose a factory processing preset to re set these time constants to safe figures From the Processing Compression Multipressor sub menu select Attack Release to bring up the formidable panel shown here Note that each band has A Attack and R Release data entry boxes that may be bracketed selected and changed Release times can never be shorter than attack times or put another ...

Page 33: ...This processing is pur posely conducted in the monaural L R domain to maximize the effect and to prevent creation of stereo difference energy at these low frequencies The two controls Punch and Rumble allow for individual ad justment of these bass effects Each control may be set be tween 0 off and 10 maximum In setting these let your ears and your conscience be your guide Despite the desire for th...

Page 34: ...VID IV peak controller behaves much like any contemporary lookahead limiter In the PIPP mode the program audio waveform is split into positive going and negative going components Each half of the waveform is then independently limited to a peak value that corresponds to 100 carrier modulation in the respective direc tions and the components then recombined The purpose of this somewhat roundabout e...

Page 35: ...ly a couple of milliseconds but this practice prevents flat top clipping of the program wave form during the limiter s initial gain reduction attack phase Avoiding flat top clipping through the use of lookahead limit ing eliminates short term transient intermodulation distortion TIM of the program audio Clipping whether hard or soft is generally to be avoided in flat power bandwidth transmission b...

Page 36: ...a similar function for the average level or loudness of the program The attack time of the DAVID IV peak controller roughly matches the delay of the limiter lookahead feature Limiter re lease on the other hand has a dual slope platform function with a quick release to the platform value and then a much slower release of the platform itself The limiter platform is based on program average energy co...

Page 37: ...ed and integrated in a floating 1 minute measurement window It states that this value should not exceed the r m s power of a single tone sine wave modulated with a peak deviation of 19kHz Now 19kHz is just about 12dB below the 75kHz peak devia tion limit This implies an average to peak ratio of the program signal that by contemporary broadcasting standards gives a rather pathetic showing certainly...

Page 38: ... fea tures ADAPTIVE PRE EMPHASIS FM broadcasting makes use of audio pre emphasis in transmis sion and complementary de emphasis in the receiver This practice requires special consideration with respect to program peak control FM pre and de emphasis characteristics were established in the 1940s These were far simpler times in radio programming long before the term competitive loudness was on the li...

Page 39: ...r FM program transmission It is a fulltime func tion for the composite MPX outputs but is applied to the ana log and digital line outputs only in their FM modes for feeding an FM exciter with a built in stereocoder The characteristics of adaptive pre emphasis are set when the pre emphasis selection is made 75 microseconds for the West ern Hemisphere 50 microseconds for Europe and most other export...

Page 40: ...io receiver first tunes and plays analog audio to the listener but then it cross fades to digital reception once the digital signal is acquired If this were not the practice then using pushbutton presets would be an ago nizing process much as digital TV channel surfing can some times be frustrating though to a lesser extent because of shorter delay in TV signal decoding This time aligning diversit...

Page 41: ...jog wheel slowly for precise 1ms steps Keep in mind that the setting will not become active until the knob is pushed committing the set ting to memory The delay is most easily set using an HD Radio receiver that can be put into the split mode where the analog program is heard in one stereo channel and the digital program in the other Turn and push the jog wheel to hone in the timing so that there ...

Page 42: ...o feed an FM exciter that has a built in stereo coder stereo gen The line output will include adaptive pre emphasis and the 15kHz low pass filtering required for stereo pilot protection and is pre emphasized in this mode This means that any pre emphasis option in the exciter should be switched OFF If HD Radio delay is enabled the line output will be delayed just as it is for the multiplex output N...

Page 43: ...al dBm voltage values the u referring to un loaded open circuit volts 0dBu 0 775V r m s rather than one milliwatt in a 600 ohm circuit 0dBm NOTE The output level in dBm feeding a 600 ohm termina tion may be set by adding 2 5dB to the numbers shown below the slider e g 6 5dBu 4dBm when the output is loaded The range of the Analog Level control covers traditional studio line levels e g Plus Four and...

Page 44: ...ansmission and the FM receiver pro vides the complementary de emphasis The time constant of the pre and de emphasis networks is determined by geograph ic location The Americas Western Hemisphere have standard ized on a 75 microsecond curve and Europe has chosen 50 microseconds Other parts of the world have opted for one or the other of these so make sure you know what setting is the proper one for...

Page 45: ...mposite MPX outputs are individually adjustable The open circuit peak to peak voltage at the rear panel BNC connectors is displayed below the slider window This voltage level which represents 100 program peak carrier modulation is adjustable between 0 8V p p and 9V p p 12dBu Turn the jog wheel to bracket the appropriate slider MPX Level 1 or MPX Level 2 push the knob to select it and then turn the...

Page 46: ...irst to back the RDS Injection slider all the way down Turn the jog wheel to bracket the slider push the knob to select it and then turn the knob counterclockwise until the lighted portion of the slider is off the bottom of the scale Note that the numbers below the slider do not change during this operation Next connect your encoder If it is programmed and ready to go turn the jog wheel to bracket...

Page 47: ...d consultants ranging from classically trained musicians to teenage hooligans hanging out at the local mall These presets may be used as is or may serve as a starting point for your own thoughtfully tweaked pro cessing setups Factory F presets cannot be changed but any one may be modified renamed and saved as one of your own Creating Custom Presets You may start with the F Flat setting or with any...

Page 48: ...resets Your selected preset will flash and when you push the knob it will be deleted If you happen to delete a user preset that is currently on air the preset name will revert to Empty But the processing setup will remain loaded in the DAVID IV even through a pow er cycle So if you delete a working preset by mistake you can simply rename and re save the on air setup as described above Whatever is ...

Page 49: ...can be made The password will lock both front panel jog wheel and soft ware control of the DAVID IV Highlight Security on the Administrative Settings menu and push the jog wheel Disable must be checked to set a password Highlight the Current Password field and push the knob Push and turn the jog wheel to enter a password using the up percase and lowercase alphabet numbers and any punctuation marks...

Page 50: ...ect AC mains power WARNING A hard reset deletes not only the password but will also return the DAVID IV to all factory default values Custom presets the current on air processing setup and in out level settings will all be lost Page 60 gives instructions for backing up a DAVID IV profile all settings to your computer Display Brightness The Administrative Settings menu also has a Brightness choice ...

Page 51: ...o a rout er server port on your network all settings on the IP Settings screen should populate at once as they did in the image above Dynamic IP addressing is common with DHCP mode routers and servers allowing multiple networked devices to share a limited range of IP addresses When one device disconnects from the network its address may be reassigned to another Whether connecting to a LAN or to th...

Page 52: ...entry must then be repeated for the other IP Set tings fields Gateway Subnet and DNS Entries in these fields will be dictated by existing network protocols depending on how the server or router is configured Your Network Administrator should know all about this it is not within the scope of this manual to provide a tutorial on network setup Sufficient to say that DHCP operation is the preferred mo...

Page 53: ...on the Internet Basic forwarding service may be free of charge but advanced features can command a nominal annual fee These services require registration on the appropriate Website Navigate to Setup Network Dynamic DNS Bracket the Mode field and push the knob Next turn the knob to reveal the three Dynamic DNS forwarding services These are dyndns org no ip com and dnsomatic com Put the traditional ...

Page 54: ...n fol lowing a power interruption and whenever the Dynamic DNS mode is altered in any way Some small part of the forwarding provider s processing re sources is used each time an IP address is renewed These pro viders especially the for free ones don t appreciate repeated and unnecessary IP address renewals If a particular account makes a nuisance of itself the provider may justifiably cut the user...

Page 55: ...municating with the DAVID IV over a network connection DIRECT COMPUTER CONNECTION TO THE DAVID IV If your station does not have a local network perhaps the easi est way to have computer control over the DAVID IV is by using an inexpensive 4 port router to create a Tabletop LAN All you need to do is plug the DAVID IV into one router port and the computer s LAN cable into another No WAN Internet con...

Page 56: ... a Wi Fi connection with Internet availability Next simply use a straight through LAN cable to connect the DAVID IV to the LAN port of your computer After a half minute or so the computer will recognize that something is connected and show it like this Don t be concerned over what Windows calls this network as it will depend on what old abandoned connections may still be resident in the Registry T...

Page 57: ...DAVID IV Settings Now we need to assign a static IP address to the DAVID IV Us ing the jog wheel in the manner described under Manual IP Setup Page 47 enter IP settings for the DAVID IV as follows Static IP IP 10 0 0 100 Gateway 10 0 0 1 Subnet 255 255 255 0 DNS 10 0 0 1 This gives the DAVID IV a compatible bogus IP setup which we will use only for this direct connection At this point you may star...

Page 58: ... the computer screen If communication is lost the DAVID IV continues working indefinitely with the parame ters set at the time the link was broken even through local power interruptions These settings will again be reflected on the computer screen immediately upon reconnection INSTALLING THE SOFTWARE DAVID IV software is supplied as a Microsoft Windows Installer Package file with a msi extension T...

Page 59: ... the DAVID IV software Confirming a Network Connection Before starting the software utility check to see that your com puter and the DAVID IV are both connected to your local net work Using the front panel jog wheel navigate to Setup Network Status If the DAVID IV has a network connection in this case the Tabletop LAN described on Page 51 the menu screen should look something like this The screen ...

Page 60: ...he default number 719 in the Port field unless you must address two DAVID IV units behind a common external IP address Page 48 If you have al ready protected the DAVID IV with a password Page 45 then you must type that into the Enter Password box on the right Now click the Connect button to invite the software to com municate with the DAVID IV Interactivity will be indicated by appearance of the b...

Page 61: ...l can be duplicated at a re mote location using the DAVID IV software routine This in cludes setting all input and output levels adjusting all pro cessing parameters and using and saving processing presets Because software control simply mirrors the adjustment rou tines already discussed in Section III the various adjustments will not be detailed here again except where differences exist The softw...

Page 62: ...f you change a setting and then put it back the way it was All changes are registered Click Save New Preset and a pop up box will appear Name your new preset and click OK Your preset will become resident in DAVID IV firmware and be added to the list This is the preset on air right now and it will remain so until another preset is selected To delete a user preset via software control highlight sing...

Page 63: ...oard has been installed Page 36 All sliders and radio buttons on these tabs reflect the DAVID IV menu driven jog wheel adjustments which have been explained in Section III Admin This tab gives access to the Administrative settings the securi ty password utility a place to enter the IP address of the DAVID IV to enable communications and selection of the Proof mode Adjusting the brightness of the g...

Page 64: ...i ated sites that want to sound the same Saving a Profile Click File at the top of the software screen The first two options Save Pro file to File and Load Profile from File refer to all settings and custom presets cur rently resident in the DAVID IV firm ware This includes processing prefer ences input and output level settings RDS injection in short everything that has been adjusted either by th...

Page 65: ... IV User presets are saved individually as single files A preset file will not include setup parameters levels RDS in jection etc but only the processing adjustments for that par ticular single preset This means that a preset file can be used among multiple installations that all want to sound the same but the imported preset will leave in out levels and other setup parameters properly adjusted fo...

Page 66: ...r profiles or another folder created the same fashion as described under the Sav ing a Profile heading Page 60 The file with that preset will be saved with its listed name and a D4p ex tension Importing a Preset Importing a preset is just the reverse process Click Import a Preset navigate to the folder on the computer where presets are held Highlight the preset and click Open The saved pre set wil...

Page 67: ...ser processing presets Firmware updates are bootloaded into the DAVID IV A bootloader is a simple software routine that runs on a PC con nected to the DAVID IV Refer to Section IV for specifics on in terconnecting the DAVID IV to your computer either over a LAN network connection Page 47 or directly with a CAT5 ca ble Page 51 Firmware Update Files A firmware update will be supplied as a zipped fol...

Page 68: ...ep 1 advises that the DAVID IV must itself be in the Firmware Update mode Using the front panel jog wheel navigate to Admin istrative Firmware Update This will bring up the first of two screens each with a stern warning about proceeding If you have backed up your Pro file and are reasonably certain that the DAVID IV and your computer are ready to con nect properly select Yes in the next two menus ...

Page 69: ...this message on your DAVID IV it is almost too late to turn back you have com mitted to uploading the new firmware If for some reason the Firmware Updater cannot connect to the DAVID IV and you have not yet initiated Step 2 to begin the update routine even at this point and with this message showing you may power cycle the DAVID IV as a last ditch means of aborting the process and returning to the...

Page 70: ... 66 NOTES AND DOODLES ...

Page 71: ...modification or if the serial identifi cation label has been removed or altered III TERMS OF WARRANTY Inovonics Inc products are warranted to be free from defects in materials and workmanship A Any discrepancies noted within THREE YEARS of the date of delivery will be repaired free of charge or will be replaced with a new or remanufactured product at Inovonics option B Parts and labor for factory ...

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