Peavey 112MX Enclosure materials and finish, Mounting provisions, Dimensions H x W x D, Features

Enclosure materials and finish:

3/4" OSB finished in black carpet

Mounting provisions:

This unit is not designed for overhead suspension.

SA 1 stand mounted adaptor

Dimensions (H x W x D):

Front:

15.25in. x 22.25 in. x 15.00 in. 387 mm x 565 mm x 381 mm

Net weight:

50 lbs. (22.7 kg)

Features:

•Two-way, full range/biampable PA enclosure

•Sound Guard™ HF driver protection circuit

•RX™22 driver with a 2" titanium diaphragm coupled to a CH® 3 90° X 45° constant-directivity horn

•12" BWX Black Widow® with Kevlar® cone and field-replaceable basket

•SP™ X series cabinet with integral stand adapter

•Neutrik® biamp jack

•30o or 45o baffle angle

Description

The SP 112MX is both a cosmetic and performance redesign of the SP 112M

SP 112 MX exceeds a predetermined threshold, the Sound Guard III circuit is engaged. The effect that this has is to subtly decrease the signal level going to the RX22 so that it will not be damaged due to longterm overpowering. Short duration transients will not be attenuated by Sound Guard III and have the possibility to damage the RX22. The Sound Guard III circuit is a dynamic circuit that will attenuate the signal more the larger the signal is, very similar to a compressor. This is accomplished through the use of a specially selected, dynamically resistive light bulb. If the bulb in your Sound Guard III should ever burn out a replacement may be obtained from an Authorized Peavey Service Center. However, if a Peavey replacement bulb is not readily available, a Sylvannia SK3 bulb may be located at various loudspeaker or electronics parts stores.

Frequency response

This measurement is useful in determining how accurately a given unit reproduces an input signal. The frequency response of the SP 112 MX is measured at a distance of 1-meter using a 1 Watt (into the nominal impedance) swept-sine input signal. As shown in figure 1, the selected drivers in the SP 112MX combine to give a smooth frequency response from 120 Hz - 14 kHz.

Power Handling

There are many different approaches to power handling ratings. Peavey rates this loudspeaker system's power handling using a full-range form of the AES Standard 2-1984. Using audio band 20 Hz to 20 kHz pink noise with peaks of four times the RMS level, this strenuous test signal assures the user that every portion of this system can withstand today's high technology music. This rating is contingent upon having a minimum of 3 dB of amplifier headroom available.

Harmonic Distortion

Second and third harmonic distortions vs. frequency are plotted in figures 3 and

4 for two power levels. Ten percent (10%) of rated input power and either one percent (1%) of rated input power or one Watt, whichever is greater. Distortion is read from the graph as the difference between the fundamental signal (frequency response) and the desired harmonic. As an example, a distortion curve that is down 40 dB from the fundamental is equivalent to 1% distortion.

Mounting

Warning: This unit is not designed for overhead suspension.

floor monitor loudspeaker system. This high power handling, two-way loudspeaker system is comprised of a 12" BWX woofer with a Kevlar impregnated cone and an RX22 compression driver coupled to a CH 3 constant directivity horn. This unit can be driven in full-range mode simply by plugging into one of the two 1/4" phone jacks on the input plate. A Neutrik Speakon® connector is provided as an input for biamp operation. The unique design of the enclosure allows the baffle to be angled at either 30° or 45° from the floor. The SP 112MX is constructed of 3/4" OSB and covered with Peavey’s durable black carpet. A powder coated expanded metal grille covers the front of the enclosure to protect the drivers from unforeseen accidents. A stand mount adapter is also included in one of the ends of the enclosure. This will allow it to be used as a PA type loudspeaker if needed.

Sound Guard III is the redesign of Peavey’s proprietary circuit for high frequency driver protection for the new RX22 compression driver. This is an integral part of the crossover for the SP 112MX. The input signal is routed through the Sound Guard III circuit in both full- range and biamp modes of operation. When the high frequency drive level to the

		Amplitude Response				(1W 1m On-Axis)
	110
Pa)	100
20	90
(re
dB SPL	80
	70
	60	50	100	200	500	1k	2k	5k	10k	20k
	20
	Figure 1				Frequency (Hz)

					Impedance
	100
	50
	30
	Z 20
(	) 10
	5
	3
	2
	1	50	100	200	500	1k	2k	5k	10k	20k
	20
	Figure 2				Frequency (Hz)

2