STUDIO PROJECTS SP828 User manual

SP828 MICROPHONE PREAMPLIFIER
visit our web site at studioprojects.com
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STUDIO PROJECTS
DISTRIBUTED BY PMI AUDIO GROUP
1845 W. 169th Street
Gardena, California 90247 USA
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INSTRUCTION BOOK CONTENTS What is Studio Projects............................................................................................2 Front Panel Controls – Individual Channel Controls.............................................3 Front Panel Controls – Master & Monitoring Controls............................................5 Rear Panel Connections – Individual Channel Jacks...........................................6 Rear Panel Connections – Master Jacks................................................................7 Block Diagrams ........................................................................................................8 Specifications........................................................................................................10 Problems..............................................................................................................11 Troubleshooting......................................................................................................11 Origins and manufacture.........................................................................................11 Declarations of conformity........................................................................................11 WHAT IS STUDIO PROJECTS? Studio Projects is a technology company committed to designing and bringing to market high quality pro audio products at an affordable price. As a small sized company with lower expenses than many of our competitors, we pass along the savings to our end users. When we introduced our “C” Series microphones in 2001, both end users and reviewers acclaimed the build and sound quality as nothing short of amazing. Pushing the “Price Vs. Performance” envelope even further, we brought out the “B” Series mics in 2002. As part of the “B” series we introduced our first electronics product, the highly acclaimed VTB1 Mic Pre/ Direct Box. Now we offer our second release in what will be a series of electronics products, the SP828. This unique product offers the best possible quality and feature set in its price class. We hope you enjoy using it as much as we enjoyed making it for you!
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Studio Projects is manufactured and
marketed under the direction of:
PMI AUDIO GROUP
USA: 1845 W. 169th Street
Gardena, California 90247
toll free: 877-563-6335
fax: [phone]
UK: P.O. Box 358
Torquay, Devon TQ2 5XS
tel: [phone]
email: [email protected]
FRONT PANEL CONTROLS - INDIVIDUAL CHANNEL CONTROLS 1) Mix Level to L/R bus Controls the amount of the channel signal that is sent to the L/R mix buses. Use these individual channel level controls to create a mix of all the channels within the SP-828. NOTE: This control does not affect the level at the rear-panel Channel Output jack (#16). 2) PAN to L/R bus Positions the channel in the L/R mix. CCW is full Left, CW is full Right. The channel signal will be 3dB down to both buses in the center-detent position. Create a stereo blend of the 8 channels within the SP-828 with the PAN controls. 3) SOLO switch & LED When depressed, the LED illuminates and the channel’s signal is sent to the SOLO mix bus. This signal is independent of the Mix Level, only the Preamp controls (#6, #7, #8) will affect this signal. Use the SOLO system to set the Preamp gain (#8) for proper signal level. 4) Signal & Peak LED This LED will vary in Green intensity with the signal level of the channel. It will turn Red when the channel level is within 3dB of clipping. Used with the Solo system and Preamp Gain to properly set the channel level. 5) +48v Phantom Power This switch applies +48 volts to Pins 2 & 3 of the channel XLR connector. This Phantom power (as it’s called) is used to power condenser microphones and direct boxes. It is not needed for Dynamic microphones and should be avoided with Ribbon mics.
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FRONT PANEL CONTROLS - INDIVIDUAL CHANNEL CONTROLS 6) Line select / Mic Pad This switch selects between the XLR and TRS connectors on the rear panel. When UP, the XLR connector is selected, when depressed the TRS jack is selected. The two jacks are “normalled” together in that the XLR signal is available at the TRS jack if nothing is plugged into the TRS jack. This allows the switch to do double-duty as a Line-select switch (if a plug is inserted into the TRS jack), or as a -20dB PAD switch for the XLR jack if nothing is plugged into the TRS Line jack. 7) Polarity reverse This switch reverses the balanced connections to the preamp circuit and therefore reverses the polarity of the input signal. This switch is sometimes called “Phase”, or marked as “Ø” on other products, but the function is the same. It is used to change the overall polarity of the signal. This matters most when the signal is being mixed with other signals. The overall sound of the mixed signals may change depending on the position of the switch. Try both positions when mixing channels together (through the L/R mix controls) 8) Preamp Gain This rotary control varies the circuit gain of the preamp. The minimum gain of the preamp is approximately 15dB, the maximum is 65dB. By using the Line/PAD switch, a wide-range of input signals can be accommodated. This control should be used in conjunction with the Solo switch and Sig/Peak LED to properly set the channel gain: adjust the Gain control so that the Sig LED is a strong Green intensity, occasional Red peaks are OK. By using the Solo switch (#3), the channel can be monitored on the Level meters (#9) and heard in the headphones.
FRONT PANEL CONTROLS - MASTER & MONITORING CONTROLS 9) Level Meters These meters allow the user to monitor the main L/R mix output, or individual channels by using the channel Solo switches. Normally, the meters are show- ing the output level of the L/R mix (controlled by #11). When any channel Solo switch is pressed, that channel’s signal level is displayed on both meters and the Pwr/Solo LED (#10) turns Red indicating that the meters are monitoring the Solo mix bus. The Solo mix is made up of all channels that have their Solo switch pressed, so individual channels, or a mixture of channels can be monitored. The meters have a VU-response, and will show the average level of the signal. The headphone system follows these meters, so anything that shows on the meters can be heard in the phones. 10) Power/Solo Indicator This LED normally is Green, indicating that the unit is being supplied power (via the rear AC power jack). The LED will turn Red when any channel Solo switch is pressed. This lets the user know that the meters are now showing the Solo mix level instead of the L/R mix output. 11) L/R Master Level This rotary control sets the overall level of the L/R mix output to the rear-panel output jacks. The L/R mix is the sum of all of the channels, controlled by their individual Mix and Pan controls (#1 and #2). 12) Headphone Level This rotary control sets the overall level of the headphones. The headphones follow the Level Meters and normally monitor the L/R mix. If a Solo switch is depressed, the phones then monitor the Solo mix bus. 13) Phone jack This 1/4” TRS jack is used to connect headphones to the unit. The phones normally monitor the L/R mix, switching over to the Solo bus when a channel Solo switch is pressed. Best results are obtained with studio-quality phones with an impedance of 30 to 75 ohms.
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REAR PANEL CONNECTIONS - INDIVIDUAL CHANNEL JACKS 14) XLR Input Jack This 3-Pin Female XLR jack is used to bring balanced signals into the channel. Normally, microphones are connected to this jack, and are selected by having the front-panel Line switch in the UP position, but hi-level signals can be accommodated by pressing the front-panel Line switch (#6). Input imped- ance is approx 3K ohms. 15) Line Input Jack This 1/4” TRS jack is used to bring line-level balanced or unbalanced signals into the channel. This jack is selected with the front-panel Line switch (#6). If nothing is plugged into this jack, the XLR signals are normalled into the TRS circuit which allows the front-panel Line switch to do double-duty as a PAD switch. Input impedance is approx 15K ohms, so Hi-impedance instruments (guitars, bass) should not be plugged in here. No damage will occur, but the sound will not be optimum for those instruments. Use an outboard preamp or buffer amplifier for these types of instruments. 16) Channel Output This 1/4” TRS jack is used for the channel output. Signals from the channel can be fed into individual tracks for recording. Nominal output level is +4dBu. Output impedance is 100 ohms, ground-compensated, impedance balanced. This allows this jack to be connected to balanced and unbalanced inputs without concern. Use a balanced (2-wire w/shield) cable for all connections for best results.
REAR PANEL CONNECTIONS - MASTER JACKS 17) Expansion In / Out jacks These 8-Pin mini-DIN jacks are used to tie SP-828 units together. When connected, the “Slave” SP-828 will send its signals to the “Master” SP-828. L/R mix and Solo signal and control signals are sent out of the Expansion Out jack of the “Slave” SP-828, and are received on the Expansion In jack of the “Master” SP-828. By chaining additional units together, up to 32 channels (4 units) can be mixed together and monitored from one master unit. The mini- DIN connector cables should be shielded and wired Pin-to-Pin and limited to 3 feet in length for best results. 18) L/R Insert Jacks The 1/4” TRS jacks are used to insert processing gear into the L/R mix. Stereo compressors or EQs are typically used here. The insert point is located after the mix amp and before the main level control. Tip is Send, Ring is Return, Sleeve is audio ground. Send impedance is 100 ohms, return impedance is 10K ohms. 19) Main Output Jacks These 1/4” TRS jacks are the main mixed outputs of the unit. The L/R outputs are available here as well as a summed-mono mix of the L & R outputs. The overall level is controlled by the front-panel L/R level control (#11). Nominal output level is +4dBu. Output impedance is 100 ohms, ground-compen- sated, impedance balanced. This allows this jack to be connected to balanced and unbalanced inputs without concern. Use a balanced (2-wire w/shield) cable for all connections for best results. 20) AC Power In jack This 5.5mm barrel jack brings low-voltage AC power into the unit. 18 volts at 750mA is required for proper operation. Only use the supplied AC adaptor from Studio Projects.
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BLOCK DIAGRAM - INPUT CHANNEL – 1 OF 8 SHOWN
BLOCK DIAGRAM - LEFT-RIGHT MASTER SECTION
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PROBLEMS Studio Projects electronics are extremely resistant to physical damage, but if the unit fails to work after being dropped, it should be returned in adequate packing to the supplier. A double test and inspection system means that manu- facturing faults are non-existent but should any fault occur, it will be repaired (or replaced) free of charge except where the fault has been caused by physi- cal damage. (SEE WARRANTY INFORMATION) ORIGINS AND MANUFACTURE Studio Projects Electronics are entirely designed in the USA. They are manu- factured in China under strict guidelines set by PMI Audio Group Gardena, Californa. All Studio Projects electronics are inspected and tested at the factory, then inspected and tested again at PMI Audio Groups facility prior to shipping. Studio Projects electronics meet the requirements of electronic equipment sold both in the USA, Canada, and the European Union. All Studio Projects products are CE Approved, and all power supplies are UL rated. DECLARATION OF CONFORMITY This analog audio processing equipment conforms to the standards and requirements of the European Economic Community. The EC Harmonized standards that have been applied are; a) Electrical equipment (safety) Regulations 1994 (S.I. 1994/3260) b) Electromagnetic Compatibility Directive (89/336/EEC) incorporating (S.I. 1992/2372)
TROUBLESHOOTING 1) The microphone doesn’t work! Have you got something plugged into the INSTRUMENT input or is the mic/line set incorrectly? (this can disable the microphone input) Is the phantom power on? (capacitor microphones). If there is indication on the VU LED, is the output volume control turned down? 2) Got signal going through but no output? Is there enough signal? Use plenty of drive. Is the output gain control turned up, and do you have a properly work- ing monitor system? 3) I don’t get any power! Is the supplied power supply plugged in correctly? Make sure the barrel connector is pushed all the way into the socket, and be sure you have available power to the supply.
SP828 SPECIFICATIONS Input Channel: XLR in to TRS Out Frequency Response: 20Hz – 20kHz • +0/-0.5B (Ref 1kHz) THD+Noise: <0.0002% THD 20Hz to 20kHz at -20dBu In, +15dBu out (35dB gain) Phase Shift: <+/-10 degrees 20Hz to 20kHz Gain Range: 10dB to 65dB Pad: -25db Polarity: Reverse (-180 degrees) XLR Input: 2k5 ohms Balanced, Pin 2 hot EIN: <-127dBu (@150 ohm, 60 dB gain) Max Voltage Gain: XLR-In to Chan Balanced Out=65dB TRS Line Input: 15k ohms Balance Max Voltage Gain: TRS-In To Chan Balanced Out=40dB Channel Output: Gnd-Compensated/Impendance Bal TRS • Max Out=+21dBu
Mix Outputs Mix Gain: Channel to L or R Output: +10dB Mix Insert Points: TRS Jack • Tip=Send, Ring=Return Mix Insert Levels=-2dBu Package Info Power Requirements: 18VAC, 750mA Size: 17.2” x 5.8” x 1.75” (IU)
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DISCLAIMER OF WARRANTY
EXCEPT FOR THE FORGOING WARRANTIES, PMI HEREBY DISCLAIMS AND EXCLUDES ALL OTHER WARRANTIES, EXPRESS OR LIMITED, INCLUDING, BUT NOT LIMITED TO ANY/OR ALL IMPLIED WARRANTIES OF MERCHANT ABILITY, FITNESS FOR A PARTICULAR PURPOSE AND/OR ANY WARRANTY WITH REGARD TO ANY CLAIM OF INFRINGEMENT THAT MAY BE PROVED IN SECTION 2-312(3) OF THE UNIFORM COMMERCIAL CODE AND/OR IN ANY COMPARABLE STATE STATUE. PMI HEREBY DISCLAIMS ANY REPRESENTATIONS OR WARRANTY THAT THE PRODUCT IS COMPATIBLE WITH ANY COMBINATION OF NON-PMI AUDIO PRODUCTS PURCHASER MAY CHOOSE TO CONNECT TO THE PRODUCT.
LIMITATION ON LIABILITY
THE LIABILITY OF PMI, IF ANY, AND PURCHASER’S SOLE AND EXCLUSIVE REMEDY FOR DAMAGES FOR ANY CLAIM OF ANY KIND WHATSOEVER, REGARDLESS OF THE LEGAL THEORY AND WHETHER ARISING IN TORT OR CONTRACT, SHALL NOT BE GREATER THAN THE ACTUAL PURCHASE PRICE OF THE PRODUCT WITH RESPECT TO WHICH SUCH CLAIM IS MADE. IN NO EVENT SHALL PMI BE LIABLE TO PURCHASER FOR ANY SPECIAL, INDIRECT, INCIDENTAL, OR CONSEQUENTIAL DAMAGES OF ANY KIND INCLUDING, BUT NOT LIMITED TO, COMPENSATION, REIMBURSEMENT OR DAMAGES ON ACCOUNT OF THE LOSS OF PRESENT OR PROSPECTIVE PROFITS OR ANY OTHER REASON WHATSOEVER.
OWNERS REGISTRATION CARD
TO BE COMPLETED AT TIME OF PURCHASE
Name _____________________________________________ Date of Purchase ____________________________________ Serial Number ______________________________________ Dealer’s Name ______________________________________
RETAIN FOR YOUR RECORDS
PLEASE DISPATCH AND RETURN
YOUR REGISTRATION
TO STUDIO PROJECTS
WITHIN 14 DAYS OF PURCHASE
Specifications and model numbers are subject to change without notice
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after investigation PMI determines that the reported problem was not cov- ered by the warranty, Purchaser shall pay PMI for the cost of investigating the problem at its then prevailing time-and-materials rate. No repair or replacement by Purchaser of any Product or part thereof shall extend the warranty period as to the entire Product. The specific warranty on the repaired part only shall be in effect for a period of ninety (90) days following the repair or replacement of that part or the remaining period of the Product warranty, whichever is greater. 2. Exclusive Remedy: Acceptance: Purchaser’s exclusive remedy and PMI’s sole obligation is to supply (or pay for) all labor necessary to repair any product found to be defective within the warranty period and to sup- ply, at no extra charge, new or rebuilt replacements for defective parts. If repair or replacement fails to remedy the defect, then and only in such an event, shall PMI exchange to Purchaser a new or reconditioned unit. Purchaser’s failure to make a claim as provided in paragraph 1 above or continued use of the product shall constitute an unqualified acceptance of such Product and a waiver by Purchaser of all claims thereto. 3. Exceptions to Limited warranty: PMI shall have no liability or obligation to Purchaser with respect to any Product subjected to abuse, improper use, negligence, accident, modification, failure of the end-user to follow the operating and maintenance procedures outlined in the users manual, attempted repair by non-qualified personnel, operation of the unit out- side of the published environmental and electrical parameters, or if such products original identification (trademark, serial number) markings have been defaced, altered, or removed. PMI excludes from warranty coverage, Products sold AS IS and/or WITH ALL FAULTS and excludes used prod- ucts which have not been sold by PMI to the Purchaser. PMI also excludes from warranty coverage consumables such as fuses and batteries, etc. 4. Proof of purchase: The dealer’s dated bill of sale must be retained as evidence or the date of purchase and to establish warranty eligibility
STUDIO PROJECTS LIMITED WARRANTY
THIS PRODUCT IS FOR PROFESSIONAL USE ONLY
PMI Audio Group warrants that all products will be free from defects in material or workmanship: A: For a period of (1) one year from the date of purchase (hereinafter the labor warranty period), PMI Audio Group will repair or replace this Product if determined to be defective. After the expiration of the labor warranty period, the Purchaser must pay labor charges. B: In addition, PMI Audio Group will supply, at no charge, replacements for defective parts for a period of (one year) from the date of purchase. During the labor warranty period, to repair the Product, Purchaser must return the defec- tive Product, freight prepaid, or deliver it to PMI Audio Group Service Center. The product to be repaired is to be returned in either its original carton or a similar package affording an equal degree of production. PMI Audio Group will return the repaired Product freight prepaid to the Purchaser. PMI Audio Group is not obligated to provide Purchaser with a substitute unit during the warranty period or at any time.
CONDITIONS
1. Notification of claims: Warranty Service: If Purchaser discovers that the Product has proven defective in material or workmanship, then written notice with an explanation of the claim shall be given promptly by Purchaser to PMI but all claims for warranty service must be made within the warranty period. If
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PRODUCT REGISTRATION INFORMATION
PLEASE FILL IN THE BELOW SECTIONS AND RETURN
Name: Address: City: State: Zip Code: Telephone Number: email Address: Model Purchased: Date Purchased: Serial Number: Dealer: Comments:
What magazines do you read to influence your buying decision: (please check all that apply)
❏ MIX ❏ Electronic Musician ❏ EQ ❏ Home Recording ❏ Pro Audio Review ❏ Recording ❏ Pro Sound News
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