How do I wire my Speakon connector?

Some Crown amplifiers feature Neutrik Speakon connectors for output wiring. Speakons allow both channels of amplifier output to be wired to the same connector. See Crown's ProGuide for using the Speakon NL4FC assembly for complete instructions (pdf file, requires Adobe Acrobat to read).

What is Crown's warranty?

Please Click here for specifics about Crown's warranty.

I want to send my Crown amplifier to the factory for service. What should I do?

Please visit this page for specific instructions for obtaining Crown factory service.

What are PIP Modules?

PIP stands for Programmable Input Processor. These are optional modules that can be plugged into any PIP-compatible amplifier. There are a variety of PIP modules with varying functions. Since first introducing PIP-compatible amplifiers and PIP modules, Crown has updated the PIP standard. This affects which PIP-compatible amplifiers can host certain PIP modules. For more information on the differences between the original PIP and PIP2 standards, click here.  

What does ODEP stand for?

ODEP stands for Output Device Emulator Protection. ODEP is an analog computer simulation of the output device thermal impedance. In layman's terms ODEP stores how much power the amplifier delivers to its load and its heatsink temperature. If the protection circuit determines that the output stage is being overstressed or cannot dissipate any further heat, then output stage drive is limited (Also see the FAQ, "What is TLC?").

What is TLC?

TLC, Thermal Limit Control, is used in some Crown amplifiers to provide the amp thermal protection, when a predetermined temperature threshold is reached, the TLC light(s) will begin to glow. This means the temperature sensing circuitry is starting to engage the input compressor. By compressing the input, the amplifier will not generate as much heat and will have a chance to cool down. The degree of compression is directly proportional to the amount of overheating experienced by the amplifier.

What is IOC?

IOC stands for Input Output Comparator. This circuit compares the output signal of the amplifier with the input signal. If there is any difference other than gain, then it is considered distortion and the indicator comes on. The LED indicator will come on whenever there is distortion of 0.05% or more. This is a dynamic Proof of Performance of the amplifiers functionality. Anytime you experience distortion in your system you can view the IOC indicators. If they are not lit then you know that the amplifier is not at fault. If the IOC indicators are on, then the amplifier is in distortion.

What is the CLIP Indicator on my amp telling me?

Crown CE Series, Contractor Series (CH/CL Series) and K Series amplifiers feature a Clip Indicator for each channel. These amplifiers also have internal compressor circuitry to prevent excessive clipping. When amplifier clipping reaches the point that the compressor turns on, the Clip Indicator also turns on to alert the operator that the input signal is being compressed. When this condition occurs, it is best to turn down the input signal level to allow the amplifier to pass a clean, uncompressed signal to the speakers.

Why the 20A and 30A AC connectors, and can I get an adapter to connect to a standard 15A outlet?

North American MA-3600VZ and MA-5002VZ amplifiers have 30 amp molded AC plugs, and North American MA-2402 and MT-2400 amplifiers have 20 amp molded AC plugs to meet regulatory requirements. AC adapters are not recommended, and may not meet local code requirements. Contact a licensed electrician for more information about AC connections and electrical codes in your area.

What is the output power rating of my Crown amplifier?

Output power specifications are provided in the specifications area for each Crown amplifier model. If you can't find your model of Crown amplifier try the Legacy amps page.

Can I run one channel of my Crown amplifier at a different impedance than the other channel?

Yes. All dual channel Crown amplifiers can be treated as if they are two separate "mono" amplifiers (One channel completely independent of the other) For example: A Macro-Tech 1202 can function with a single eight-ohm speaker on channel one and four eight-ohm speakers (a two-ohm load) on channel two. A Com-Tech 410 can function with one or two eight-ohm speakers on one channel and the other channel switched to 70-volt operation.

Should I have the level controls on my amplifier turned all the way up?

It depends on the system and how much gain you have prior to the amplifier. The level control can be thought of as an input attenuator. It does not limit the power available from the amplifier. With the level controls turned down the amplifier can still reach full rated output power, it just takes more drive level from your mixer to achieve it. Generally, you should set the mixer's individual channel fader and master gain to 0 dB, then adjust the amplifier level controls to the desired sound level.

How do I determine the best input sensitivity setting?

The input sensitivity setting is a function of amplifier gain. You will want to match it with the output level of whatever is before the amp in the audio chain (i.e. preamps, mixers). For amplifiers with a 0.775V position, this positions corresponds to a 0 dBu level. The 1.4V position corresponds to a +4 dBu level. The 26 dB position is a fixed gain position. The 26 dB position is also the lowest gain position, and will usually work well with output levels of +10 dBu (2.5Vrms and above).

How can I parallel the inputs of my Crown amplifier with the same signal?

The input impedance of Crown amplifiers is high enough that paralleling multiple inputs together is not a problem. Using a standard Y-adapter works wonderfully. Without using a Y-adapter, the procedure is different depending upon the Crown amplifier used.

With Macro-Tech amplifiers the 1/4" inputs are in parallel with the inputs of the PIP-FX. You can use the XLR connector on the standard PIP-FX as an input, and the 1/4" of the same channel as an output to another amp channel.

The standard SST input module on the CE Series and Contractor Series (CH/CL Series) amplifiers have barrier block connectors in parallel with the Neutrik Combo connector. You can use the Combo connector as an input, and the Barrier Block connector of the same channel as an output to another amp channel.

The K Series amplifiers have a "Y input" switch that internally connects both channel inputs.

The CP660 has barrier block input connectors, so the input signals can easily be jumped from one channel to another.

With the D Series, you must use a "Y" cable.

How much "inrush current" will my amp draw during turn on?

Design features of the amplifier, including power supply design and transformer size, partially determine maximum peak inrush current for a given amplifier. In addition, the external factors of AC mains voltage and impedance vary greatly making exact values difficult to determine.

Many Crown amplifiers include "Soft Start," a feature designed to limit inrush current. Worst-case peaks for amplifiers without Soft Start may reach as high as 150 amperes; however, such numbers seldom have bearing on practical operation. For example, it is not unusual to find 3 or 4 Crown Micro-Tech amplifiers on a single 15A or 20A branch circuit without tripping breakers at turn-on. There are a couple of reasons why this is possible. First, peak inrush current is usually of such short duration that the breaker will not trip (maximum duration is approximately 18 msec). Second, Crown amplifiers are designed with design tolerances in the power supply start-up circuitry to make it highly unlikely for more than one amplifier channel to come out of standby during the same 18 msec interval.

If nuisance circuit breaker tripping is a concern, "motor-start" circuit breakers, which are designed to withstand the large inrush currents from electrical motors, may be used in place of standard circuit breakers. Contact a licensed electrician for more information about circuit breaker requirements and electrical codes in your area.

How can I get rid of the noise in my system?

First let us lay some groundwork: audio systems can exhibit "hum" and they can exhibit "buzz," which are two separate situations. To solve the problem, you need to determine whether your system is exhibiting hum or buzz.

Sixty(60)-hertz hum (fifty(50) hertz internationally) is a result of having a ground loop in the audio system. This is where there are two or more ground references in the system, and current is flowing from one ground point to another. Any piece audio equipment requires one ground reference. Ground loops can be formed in a number of ways. For example: An audio power amplifier obtains its ground from the AC power cord. The mixer, which drives the power amplifier, also receives its ground from the AC power cord. When the audio cable connects the mixer to the power amplifier the amplifier now sees a second ground from the mixer. If the mixer and power amplifier are both plugged into the same AC power strip then the mixer/amplifier interconnect cable shield can be cut to eliminate this problem. On most Crown amplifiers there is a "ground lift" switch on the back of the amplifier that performs this function and can be used to eliminate hum caused by ground loops. If you are using a cable service, such as cable TV, and you are routing the audio through your stereo system, you may experience a ground loop hum. This is a result of the cable company's ground reference setting different than your system ground reference. You can contact your cable company and get an isolation transformer that will take care of the problem.

Another cause of system "hum" is electrically induced, such as having a very sensitive component too close to a power transformer. Power amplifiers have large power transformers and can induce a magnetic field into other equipment. If you suspect this may be the cause of your problem then placing more distance between the two components is the only practical solution.

Excessive "noise" on the AC mains can cause "buzz" in certain components. Lighting dimmer packs are notorious for inducing noise onto the AC mains. If this is your problem try putting the lighting system on a different AC mains feed.

Ground loops, induced hum, and all kinds of nasty noises are sometimes hard to pin point. You may have to try several different approaches before arriving at solution. For more information call the Crown Technical Support Group and ask for the Sound & Communications reprint of "The AC Connection."

What is Damping Factor?

Though technically more complex than this, Damping factor is usually thought of as an indicator of how tight an amplifier will sound when powering bass speakers. A speaker's driving motor is a coil of wire (called a voice coil) mounted within a magnetic field. As this coil of wire moves within the field a voltage will be induced in the voice coil. If resonant motions of the speaker are not sufficiently short circuited by the amplifier, the speaker output can have an over accentuated or "boomy" bass sound.

From a technical measurement stand point, Damping factor is the ratio of the rated speaker impedance to the amplifier's output impedance. Low output impedance is the consequence of the amplifier having substantial negative voltage feedback taken from its output terminals. Properly designed negative feed back not only corrects for output voltage errors induced by the speaker but also produces other benefits:

  • Low distortion
  • Low noise (hiss) 
  • Flat frequency response

What gauge speaker wire should I use in my system?

For the best speaker damping and least amount of power loss you will want to use the heaviest gauge that is practical. The length of the speaker wire should be considered when considering wire gauge. The shorter the run, the smaller gauge you can use with minimum power and damping factor loss. The longer the run, the heavier gauge you will need to minimize power and damping factor loss. You will also want to consider the size of power amplifier you are using. The larger the amplifier, the heavier gauge you will want to use. Generally speaking, runs of 25 Ft or less work well with 14 gauge. Over 25 one should use 12 gauge if possible. These numbers are not set in stone, but generally work well. For Constant Voltage systems such as a 70.7V or 140V systems, the voltage is high and the current is low. Because there is not much current you can use smaller wire without much power loss. Quite often 18-gauge wire works well with these systems. To calculate power loss you can use the Line Loss Javascript Calculator on the Crown web site. You can also request a free copy of the Crown Constant Voltage Slide Rule, which is available from our literature department. To order,1-574-294-8093 or send email to:

Should I use vented spaces between my amplifiers?

With the exception of the K Series and Commercial Audio Series amplifiers, the answer is no*. The airflow technology that we use in our amplifiers is designed such that it is best to stack multiple amplifiers on top of each other, with no space between. The amplifiers draw fresh air into the front of the amplifier and exhaust it either out the sides and into the rack, or out the back depending upon the model. We want the hot air that is in the rack to vent out the sides or back, not the front. If any of these amplifiers are spaced apart with vented panels some of the preheated air will recycle to the front of the rack. The result is attempting to use preheated air to cool the amplifiers within the rack. The result will be loss of thermal headroom. If you choose to place the amplifiers with space between them, then use solid panels between them, not vented panels.

*K Series (discontinued) and Commercial Audio Series amplifiers are convection cooled so some space between amplifiers in a rack is recommended. Refer to the corresponding manual for these, and all Crown amplifier models, for specific recommendations.

How can I augment the cooling of my amplifier racks using external fans?

Crown amplifiers draw air in the front and exit out the sides (CE Series and Contractor Series (CH/CL Series) amplifiers exit air out the back). For this reason do not install auxiliary fans POINTING IN toward the amplifiers. The following are two suggestions:
  1. Place the fan in the back of the rack pointing out or away from the amplifier(s)
  2. Seal the back of the rack with the road case cover. Mount the fans to the TOP of the road case back cover POINTING OUT.

What does 'VZ' stand for in the MA-3600VZ and MA-5002VZ amplifiers? What does it do?

VZ means Variable Impedance and is the name of Crown's patented articulated power supply technology. VZ technology enables Crown to pack tremendous power into small rack spaces.

Background: A power supply must be large enough to handle the maximum voltage and current necessary for the amplifier to drive its maximum rated power into a specified load. In the process of achieving this requirement conventional power supply designs produce large quantities of heat, are heavy, and take up precious real estate. It's no secret that heat is a power amplifier's greatest destructive factor. The larger the power supply, the more heat the output stage will be required to dissipate. An articulated power supply, like VZ, can bypass much of this dilemma by reducing the voltage applied to the transistors when less voltage is required. Reducing the voltage decreases the heat. Subsequently the amplifier runs cooler allowing more power to be safely packed into the chassis. The VZ supply is divided into segments to better match the voltage and current demands of the power output stage. Bear in mind that audio signals are complex waveforms. The average level of music is always much less than the peak level. This means a power supply does not need to provide full voltage all of the time. The VZ supply is divided into two parts. When the voltage demands are not high, it operates in a parallel mode to supply less voltage and more current. The power transistors stay cooler because they are not forced to needlessly dissipate heat. This is the normal operating mode of the VZ power supply. When the voltage requirements are high VZ switches to a series mode to produce higher voltage and less current. The amplified output signal never misses a beat and gets full voltage only when it requires it. Sensing circuitry observes the voltage of the signal to determine when to switch VZ modes. The switching circuitry is designed to prevent audible switching distortion to yield the highest dynamic transfer function-the customer hears only the music and not the amplifier. You get not only the maximum power with the maximum safety; you also get the best power matching to your load.

Should I use Bridge Mono or Parallel Mono?

Generally, the deciding factor to this dilemma is the total speaker load impedance you wish to drive. With Micro-Tech and Macro-Tech amplifiers you would want to use Bridge Mono to get the most power available when driving 8 or 4-ohm loads (one or two 8 ohm speakers). With a Power-Tech or Com-Tech amplifier you need to stay at 8 ohms or greater. Parallel Mono can be used when driving lower impedance loads. A one-ohm load can be driven Parallel Mono with a Micro-Tech or Macro-Tech. With a Power-Tech or Com-Tech amplifier you can drive down to two ohms in Parallel Mono. The biggest advantage of using Parallel Mono is when you have an odd number of speakers, such a three. Instead of leaving the amplifier in the dual mode and driving two on one side and one on the other, you can parallel all three and drive them Parallel Mono. This way the power is distributed equally to all three speakers.

How do I set up my Crown amplifier to operate in Bridge-Mono?

The following is a step-by-step procedure to set up a Crown amplifier to operate in Bridge-Mono:
  1. Make sure the amplifier is powered down.
  2. Place the MODE switch (located on the back panel) in the Bridge-Mono position.
  3. The input connector should be inserted into channel one (leave channel two's input empty.
  4. Connect the speaker leads across the two red binding posts, using channel one binding post as the + (hot) connection or on CE's with Speakons across pins 1+ and 2+ on the channel one output.
  5. Channel one level control should be used to control level.

How do I set up my Crown amplifier to operate in Parallel-Mono?

The following is a step-by-step procedure to set up a Crown amplifier to operate in Parallel-Mono:
  1. Make sure the amplifier is powered down.
  2. Place the MODE switch (located on the back panel) in the Parallel-Mono position.
  3. The input connector should be inserted into channel one (leave the channel two input empty).
  4. Place a small diameter wire (14 gage {1.63 mm}) between the two red output binding posts.
  5. Connect the speaker leads across the red and black binding posts.
  6. Channel one level control should be used to control output level.

Note: For those amplifiers with IOC (Input-Output Comparator) the channel two IOC indicator will illuminate when the unit is operated in Parallel-Mono.

Note: CE Contractor Series (CH/CL Series) CP660, D Series and K Series amplifiers cannot operate in a Parallel-Mono mode.

Which pin is hot (non-inverting) on a Crown amplifier?

Pin 1 is ground (shield).
Pin 2 is hot (non-inverting)
Pin 3 is low (inverting)

1/4" TRS
Tip: hot (non-inverting)
Ring: low (inverting)
Sleeve: Shield (ground)

Isn't Class-I just like other amplifier classes?

No, Class -I amplifiers are a fundamentally different design from all other amplifier classes on the market. Crown has patented the technology behind Class-I amplifiers and is the only manufacturer in the world building this design. 

For more information about Class-I, read this technical paper.

How does Crown measure power?

Output power is measured using the "Maximum Average Power" method. The Maximum Average Power test is designed to be an easy way to more closely approximate output power with real world musical sources. The test is simple: the amplifier is set up with the level controls turned to the maximum setting, and then a connected sine wave source is increased until the specified total harmonic distortion is reached.

What PIP modules are compatable with what amps?

We have a compatability chart available on our web site at: 

How do I update the firmware in my CDi, DSi, or XTi amplifier for use with System Architect?

Please visit this page for instructions:

XTi, CDi, and DSi Firmware Update Instructions

Why is the screen on the I-Tech 4x3500HD no longer a touch-screen?

Due to supplier issues with quality and delivery, we have removed the touch-screen capability from the I-Tech 4x3500HD. Several of the display screens and menus have been updated to accommodate this change. Performance of the I-Tech 4x3500HD has not been impacted by this change in any way.  If you have any questions regarding this issue, please contact our Technical Support team at