Samson MPL 1502 manuel d'utilisation

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Intr oduction 1 MPL 1502 Features 1 Guided T our 3 Overview 3 Mono and Stereo Channels 4 Main Section 6 Rear Panel 8 Connecting The MPL 1502 - General Suggestions 10 Setting Up and Using the MPL 1502 13 Setting the Correct Gain Structure 14 Gr ounding T echniques 16 Using Pan/Balance 18 Using Equalization 19 Using Aux Sends and Retur ns 20 Using Ch[...]

Intr oduction Congratulations on purchasing the Samson MPL 1502 stereo mixer! Although this unit is designed for easy operation, we suggest you first take some time to go through these pages so you can fully understand how we’ve implemented a number of unique features. In this manual, we’ll provide you with an overview of the MPL 1502 features,[...]

Intr oduction • Independent 3-band equalization for each channel, with 15 dB of cut or boost for low (80 Hz) and high (10 kHz) frequencies, and 12 dB of cut or boost for the mid-range (800 Hz) frequency. • Constant level pan controls for placing each monophonic channel in the left- right stereo spectrum, as well as balance controls for each ste[...]

Guided T our - Over view The following illustration shows an overview of the front panel of the MPL 1502: 3 1 2 3 −∞ −∞ −∞ +15 1 2 3 −∞ −∞ −∞ 1 2 3 −∞ −∞ −∞ 1 2 3 −∞ −∞ −∞ 1 2 3 −∞ −∞ −∞ −∞ −∞ −∞ −∞ −∞ −∞ −∞ −∞ −∞ −∞ −∞ −∞ −∞ −∞ −?[...]

Guided T our - Mono and Ster eo Channels 1: Mic inputs (1 - 5) - Provided in monophonic channels only. Use these electronically balanced XLR jacks to connect microphones to any of the MPL 1502 ’ s five mono channels (channels 1 - 5). These are intended to accept signal from low-level, low-impedance mics but can also be used for signal from other [...]

Guided T our - Mono and Ster eo Channels 6: Pan (white) - Provided in mono channels only. This knob allows you to place the input signal anywhere in the left-right stereo spectrum, while keeping the overall signal level constant. When the knob is placed at its center (detented) position, the signal is sent equally to both left and right outputs. Wh[...]

Guided T our - Main Section 1: Meter - This seven-segment bar meter shows the continuous output level of the main stereo output. For optimum signal-to-noise ratio, try to adjust all levels so that program material is usually at or around 0 VU, with occasional but not steady excursions to the red +2 or +6 segments. See the “ Setting the Correct Ga[...]

Guided T our - Main Section 4: Stereo Auxiliary Return Level (gray) - These knobs determine the input level of signal arriving via the MPL 1502 ’ s two stereo Auxiliary returns. Each return is at unity gain (no boost or attenuation) when set to the “ 0 ” (2 o ’ clock) position. The input signal is boosted when the knob is turned to the righ[...]

Guided T our - Rear Panel 1: Power on-off switch - As you may have guessed, this is what you use to turn the MPL 1502 on and off. To avoid potential damage to your speakers, turn the mixer on before you turn on any connected power amps — and turn it off after the power amps are turned off. 2: Phantom switch - When this switch is turned on, the MP[...]

Guided T our - Rear Panel 5: Main out (L, R) - These are the MPL 1502 ’ s main outputs. You ’ ll usually use these to connect the MPL 1502 to a power amp and speakers. The Main out jacks are electronically balanced, so you should use balanced three-conductor cabling and TRS plugs wherever possible (unbalanced two-conductor plugs can also be ins[...]

Connecting The MPL 1502 - General Suggestions The actual connections you ’ ll make to and from the MPL 1502 will vary accord- ing to the environment you use it in and the particular equipment you have. In the “ MPL 1502 Applications ” sections at the rear of this manual, you ’ ll find some suggested setups. Here are a few basic rules concer[...]

• For single-fader control over a pair of matched signals (i.e. the left-right out- puts of a stereo effects processor, keyboard, drum machine, tone generator, CD player, or tape recorder), use the MPL 1502 ’ s stereo input channels (6/7, 8/9, 10/11, 12/13, and 14/15). The Balance control in these channels will allow you to adjust the relative [...]

• Signals that are likely to require “ in-line ” processing (such as compression/limiting or expansion/noise gating) should be connected to channels 1 - 5, since these channels provide an insert connection. Insert cables (sometimes called “ Y-cords ” ) should terminate in standard 1/4 ” TRS jacks (ring to send and tip to return), wired [...]

13 Setting up your MPL 1502 is a simple procedure which takes only a few minutes: 1. Remove all packing materials (save them in case of need for future service) and decide where the unit is to be physically placed — it can be used on a table- top or optionally mounted in any standard 19 ” rack, requiring six rack spaces. 2. Before even plugging[...]

14 You ’ re now ready to establish the correct gain structure — the key to getting the best performance from the MPL 1502, or from any mixer, for that matter. This is a simple procedure that ensures optimum input and output levels so that no unnecessary noise (caused by too low a signal) or overload distortion (caused by too high a signal) is c[...]

15 Setting the Cor r ect Gain Str uctur e j. The procedure for setting optimum microphone levels is virtually identical; sing or speak into the mic at the level you expect to use in performance while slowly raising the gain control for that channel to its center detented “ 0 ” position. Then carefully adjust the input trim control for that chan[...]

16 Gr ounding T echniques Hum and buzz are the biggest enemies you face when interconnecting a large number of different pieces of equipment to a central audio mixer. This is because each piece of equipment may operate at a marginally different voltage (this difference is called potential ) and, when two devices at slightly different potential are [...]

17 Gr ounding T echniques If you ’ re using the MPL 1502 in a fixed location such as a recording studio, you may want to invest the time and money into creating a star ground network . This is by far the best technique for avoiding grounding problems. It involves using a formidable ground source such as a cold water pipe or a copper spike driven [...]

18 Using Pan/Balance The final Main output of the MPL 1502 is stereo — that is, there are two discrete output jacks, labeled “ left ” and “ right, ” which will normally be routed to two discrete speakers.* Because of this, you will usually be working with a stereo field that ranges from hard left to hard right. The Pan control in each mon[...]

19 Using Equalization One of the most exciting aspects of using a mixer such as the MPL 1502 is the ability to shape a sound, using a process called equalization . But there are few areas of sound engineering more misunderstood than equalization, and, just as good EQ can really help a sound, bad EQ can really hurt it, so read on... Every naturally [...]

20 Using Aux Sends and Retur ns The MPL 1502 ’ s two Auxiliary sends allow you to combine the signal from multiple channels and send the resulting mix to external devices such as effects processors. When an Aux send knob is at the “ 0 ” position, the signal is routed with unity gain (that is, no boost or attenuation). As it is turned clockwis[...]

21 Using Channel Inser ts In addition to using Auxiliary sends and returns to access outboard devices, the MPL 1502 also provides channel inserts for the first five (mono) input channels. These should be used when you want to affect just one channel ’ s signal, as opposed to signal from several channels — most often, this will be for dynamic pr[...]

22 Applications Here are four suggested applications for the MPL 1502; bear in mind that your particular circumstance may dictate changes in these suggested signal connections and routings. Application 1 - Using The MPL 1502 As A Main Live Mixer The main connections here involve routing the MPL 1502 ’ s Main output to the input of a power amplifi[...]

23 Application 2 - Using The MPL 1502 As An Onstage Monitor Mixer Here, the MPL 1502 is receiving monophonic signal into its line inputs from the direct channel outputs of a main live mixer. Its Main output is connected to an outboard signal processor (typically an equalizer) prior to being routed to an amplifier and onstage monitors. This allows t[...]

24 Application 3 - Using The MPL 1502 As A Keyboar d Submixer Here, various keyboards and MIDI tone generators are connected to the mono and stereo line inputs of the MPL 1502. Signal processors are connected to Aux sends and returns and to channel inserts as required. The Main output can then be routed to a stereo input channel of a live performan[...]

Applications Application 4 - Using The MPL 1502 For Recor ding You can also use the MPL 1502 for making simple recordings — for example, when recording a rehearsal or practice session direct to open-reel two-track, cassette, or DAT recorder. Connect the MPL 1502 tape outputs to the inputs of the two-track tape recorder, and connect the Main outpu[...]

26 Specifications 1. Frequency Response (0 dB = 1.0 V RMS) 17 Hz to 30 kHz ± 1.5 dB at +4 dB 2. Equivalent Input Noise Ch. 1 - Ch. 5 Mic input -128 dB (A filter, 150 Ω shorted) Ch. 1 - Ch. 15 Line input -131 dB (A filter, input shorted) 3. THD+N (unity gain, 20 Hz - 20 kHz) Less than 0.03 % 4. Input Level Ch. 1 - Ch. 5 Mic input -50 dBV to +4 dB[...]