Electro-Voice P1250 (1995)
A German-built, processor-equipped touring amp that put a loudspeaker's thermal behavior inside the chassis - and listed at $1,900.
Overview
Where the P1200 is a straight power amp, the P1250 carries a processor section with loudspeaker-specific bass tuning built in, which is why the two share a power rating but not a price:
The headline numbers are what got it into touring racks. EQ (August 1995, p.80) measured a clean 1000 watts into an 8-ohm load in bridged-mono mode. It also measured 350 watts per channel at 8 ohms and 500 watts per channel at 4 ohms across 20 Hz to 20 kHz. The same review quotes 370 watts per channel at 8 ohms at 1 kHz, which is the figure Electro-Voice used in its own lineup pricing. Treat the two as different measurement conditions, not a contradiction. This amp is built to drive real loads at volume, and the bridged-mono rating is the one that matters for anyone running subs.
The odd part of the P1250 is the Thermal Brain Circuit. EQ (August 1995, p.80) described it as a proprietary circuit that emulates the thermal behavior of a typical low-frequency driver. That lets the amplifier deliver roughly 40 percent above its rated power for short durations without cooking the voice coil. Transients pass, and long-term power doesn't overheat anything. The review was honest about the limits: the circuit is not smart enough to recognize that a cheap 50-watt woofer is connected before melting it, though it will still protect the amplifier afterward. The amp assumes you know what you're doing.
The processing is where the P1250 earns its keep over the P1200. A rear-panel switch selects a 12 dB/octave high-pass filter at 15 Hz, 31 Hz, or off, applied to both channels. The low-frequency boost filters are more interesting. They conform to the response of specific loudspeaker tunings, and Electro-Voice supplied a table in the manual for matching its own TL-series cabinets in what the company called "step-down" tuning. That extends their bass response while the amplifier's excursion protection keeps them safe. There's also an LPN mode intended for compact full-range boxes. It applies a second-order shelving filter at 50 Hz to make a small vented cabinet sound like it has subwoofers behind it. EQ (August 1995, p.80) liked the concept and flagged the obvious hazard: with small, less capable loudspeakers at high sound pressure levels, that much bass boost will make them sound distressed and raise their harmonic distortion. The review put it bluntly. The P1250 has settings on the rear that could easily destroy inappropriate loudspeakers, and Electro-Voice gives the user credit that they'll only be applied to cabinets that can take them.
The construction explains why these amps are still being serviced three decades on. EQ (August 1995, p.80) attributed the build quality directly to German manufacturing of the Precision Series by Dynacord for Electro-Voice. It also noted that while the line was very definitely aimed at live sound and touring, it was built to the standard of a fine studio monitor amplifier.
The rear panel is dense with the kind of flexibility that separates pro amps from consumer ones. There are balanced XLR inputs per channel, with an optional transformer. Speakon outputs come with two cable connectors included. XLR-M connectors cascade inputs to another amplifier. Recessed sliding switches handle chassis ground lift, parallel-mono or dual-channel input mode, bridged or normal output mode, and fast or slow time constants for the overload-protection limiter - fast for high-frequency duty, slow for bass and sub-bass. Internally, jumpers select between 26 dB of constant gain, full power at 0 dBu, or full power at +6 dBu. The amp can be adapted to most any gain structure and grounding scheme in a system, rather than forcing the system to adapt to it.
The front panel carries two input attenuators with detents and unusually fine adjustment near the top of their range. EQ (August 1995, p.80) listed the markings running from 0 through -0.1, -0.8, -1, -2.2, -3, -5, -6, -8, -10, -12, -17, -26, and -62 dB, tracking accurately across both channels. The same review flagged the one ergonomic stumble: the level control knobs have a position indicator that is very hard to see from a distance. LEDs cover power on, input signal presence, output signal presence, limiting, protection mode including muting during power up and down, and processor functions on. Variable-speed fans handle cooling under a well-managed thermal control system. EQ (August 1995, p.80) called them very quiet and specifically noted they avoid becoming the howling monsters found in many amplifiers.
Serviceability is a real selling point. The review noted that the amplifier ships with complete service instructions, bench-alignment procedures, and detailed schematic drawings alongside a concise owner's manual.
The known weakness is mechanical, not electrical. EQ (August 1995, p.80) listed a requirement for a deep 18-inch rack among the amp's drawbacks. Standard shallow racks won't take it, so anyone planning an install around a P1250 needs to check rack depth first. The second listed weakness is that hard-to-read attenuator indicator, which is minor but persistent.
EQ (August 1995, p.80) recommended the P1250 for applications where its full output capability and processing can be used to advantage. It described the filter set as a convenient alternative to a separate processor, with the bass enhancement of outboard gear tucked inside a sound-reinforcement amplifier. The review's verdict was that for anyone needing a power amp without the additional processing, Electro-Voice had other models sharing the basic design and construction. The P1250 is the processing model, and if you don't want the processing, the P1200 is the same amplifier with a smaller price tag. A separate Dynacord-era document notes that when the P1250 is used in active two-way systems with subwoofers, the processor section can simply be switched off.
The paper trail has gaps. The Precision Series is documented in period press and in surviving manuals, and the P1250's place at the top of the line is well established. Production years beyond the 1995 review date, original shipping volumes, and current market pricing are not established in the available documentation. The design intent is clear: a two-rack-space, Dynacord-built, processor-equipped touring amplifier with comprehensive protection, loudspeaker-specific bass tuning, and enough documentation to keep it running.
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