Power amplifiers/speakers

[Landon]

I have heard conflicting recommendations on using the power conditioner to supply power to power amplifiers or powered speakers. How many people just plug into the conditioner or straight into the outlets?

I think that plugging directly into a wall outlet is just asking for a damaging surge to happen Moreover, if you have dirty power, its not going to help things either. As long as your power amps aren't drawing that much current (most new amps are much more efficient), I don't see why a power conditioner (or two) wouldn't work just fine.

Before I started using a power conditioner, I used a simple surge protector for just the amplifier and plugged it into its own outlet. They even have some conditioners with reserve power which actually increases the available power on the line for peak transients over bare wall outlets.

[michaelhoddy]

Commercial power amplifier power supplies are generally incredibly robust, and are not bothered by many of the line and interference issues that affect more sensitive electronic gear. That, and any larger amp is going to draw more AC current than a typical power conditioner is rated to handle, especially in multiples. These are the two main reasons many people don't run amps through conditioners.

If your amps are low-current enough to run on a conditioner, you're certainly not hurting anything with it though.

No typical power conditioner has enough reserve current capacity to do anything tangible to improve the peak current demands of a typical amp beyond what it already does for itself. This is in fact what the power supplies in amplifiers do already, hence the large electrolytic capacitors present in all power amplifiers.

[Landon]

I just heard about many guitar amps blowing from "dirty power or spikes/surges". Looks like I've been unnecessarily precautions using surge/spike protectors for my power amp....

So my Mackie FR1400 will be safe just going into the outlet direct? I guess that's why quality power amplifiers have breakers on them right?

So I guess the fancy "power reserves" are just gimmicks that just try to fix something that ain't broke?

[michaelhoddy]

There certainly is dirty power out there, but unless something's wired wrong in the premise wiring or lighting strikes the building or close to it, the chances of a properly-designed power amp blowing up from common line variations is pretty slim. Even brownouts, which are the most common type of line fault, won't do much to the average power amp except kick it into protect.

Can't speak to the examples you've heard about, but I'd bet there are other factors in play. I've lost gear (and never power amps) to electrical line issues only about twice in twenty years.

The "power reserve" thing in some power conditioners is probably an electrolytic capacitor circuit. These may supply enough current for a brief moment to low-draw digital gear, but they won't supply enough current to do anything meaningful for a power amp.

[Landon]

Thanks a million Michael! That saves slots on my conditioner

[Landon]

How far do you guys usually run your speaker cables from amplifier rack? I am running 25'.

[miket156]

Twenty five feet is fine for speaker cables. No loss of signal.

I use a line conditioner for everything, including and most importantly for my power amp. AC power is dirty power. DC power is better because of the nature of the power, it doesn't vary. But what we use is AC power and we have to deal with what we have. Power conditioners filter "noise" out of AC power and a decent one will have a power indicator that will tell you how much AC power you are getting. If the current drops too low you can damage more sensitive instruments.

One other thing I keep in my cable/accessory box is an outlet tester. If you are playing a room you have never played at before, be sure to check the outlet you are going to be drawing current from to be sure it has a good earth ground and that it is wired correctly. In the USA, there are building codes so the electrical circuits must be up to code or they won't pass electrical inspections. A building that was built in the last 20 or 25 years should have good outlets. But it doesn't hurt to check.



Mike T.

[michaelhoddy]

AC power is dirty power. DC power is better because of the nature of the power, it doesn't vary. But what we use is AC power and we have to deal with what we have. Power conditioners filter "noise" out of AC power and a decent one will have a power indicator that will tell you how much AC power you are getting. If the current drops too low you can damage more sensitive instruments.

Before I respond in detail, could you elaborate on what you mean by a few things, just so I understand where you're coming from a bit better. I'm not asking these as questions as much as I want to understand your perspective:

What you mean by "AC power IS dirty power?" And also what in the nature of DC power makes it better?

What kind of "noise" do power conditioners filter out that would in any way affect the power supply of a power amp?

How does "too low of current" damage equipment without tripping a break or fuse or other protection?

Finally, which power conditioners offer a current indicator? Off the top of my head, I can think of several which monitor voltage, but none which monitor current.

[miket156]

I used “Current’ instead of “voltage”. My mistake.

Many delicate electronic devices use DC power, not AC like refrigerators and other household appliances. You will probably see a lot of Electronic items that have an adapter that you plug into an AC power outlet, but the device is running off DC power via the “transformer” which is actually a full wave bridge rectifier. (Typically 4 diode rectifiers in a circuit) DC power is better because it only moves in one direction and is a lot more predictable. Being that not all countries run on the same type of power or use the same color wires in the AC wiring, adapters can be made for electronic devices being shipped to different countries, it can be made to accept that country’s AC power and will always provide the correct DC power to their device.

Alternating Current- Dirty power is actually noise in the AC power lines, caused by electro-magnetic interference (EMI) and radio frequency interference (RFI). EMI is caused by electrical interferences from appliances, especially those that use motors (copying machines, air conditioners, refrigerators, washing machines and vacuum cleaners). RFI is caused by interference from radio devices such as cordless phones, microwave ovens, cell phones and others. The myriad electrical wires are usually not shielded and are affected by RFI and EMI interference. The solution is EMI/RFI filtering built into many power protection devices, which filters out noise in the AC power line and provides clean power to connected components.

The best protection for equipment is a dedicated circuit within a building. How many places that you play have a dedicated circuit for entertainment only? Probably none. The best protection is an Isolation Transformer Line Conditioner. They are not terribly expensive anymore. Here is an example:

Tripp Lite® Isolation Transformers-Complete line isolation, noise filtering, and surge suppression offers 100% isolation from input AC line Isolation transformer design serves as an alternative to installing dedicated circuits and electrical upgrades. Remove EMI/RFI noise, utility switching transients, background spikes, and power problems generated by other on-site loads, utility grid-switching, and lightning related surges. Surge suppression components offer continuous line filtering of a full range of power line noise in all modes. Transformers feature NEMA 5-15P input and NEMA 5-15R output outlets. $164.44

The "standard" power conditions do not incorporate an Isolation Transformer and really don’t offer much protection for your equipment. Also, surge suppressors cannot respond quickly enough to “eliminate” a lightning strike that is close by. How much energy is in a lightning strike (rather than lightning between clouds that doesn’t hit the ground) is substantial. It can be 100,000,000 volts and a lot of heat to go along with it. I don’t know of any surge suppressor that can handle lightning strikes that are close by or hit your building. Lightning rods are a good idea. The best thing to do is turn off your equipment during an electrical storm, unplug it from the power outlet, and move the power cable far away from the wall outlet. In extreme cases, unplug all your equipment too.

Cheers,


Mike T.

[Landon]

Yep... some people think that a surge protector will protect their equipment from lightning... an expensive mistake. It is best just to unplug during a storm unless you have a generator

[Dave Burris]

How far do you guys usually run your speaker cables from amplifier rack? I am running 25'.

Depends almost entirely on the gauge of your cable. However in most cases 25' feet is not a big deal.

[miket156]

Good point, the gauge of the cable is very important. I have to say that, if you go into most any music store, you generally don't find the old "zip cable" which looks like telephone cords. Most places will sell you a fairly heavy gauge speaker cable. Buy the same length for both speaker cabinets. Don't fall for Monster cables. They are over priced and won't make a bit of difference other than the contents of your wallet.


Mike T.

[Landon]

Depends almost entirely on the gauge of your cable. However in most cases 25' feet is not a bit deal.

I use Monster Standard 100 with Hosa Speakons. I figured that 25' was pretty much the norm. I know that 10 and 12 gauge cable can go out a bit further, but I like to keep my cable runs short though (less cable tying lol). I bought the Monster stuff a couple years ago since that's what my old store had lol. I don't think it's really any better than Pro Co to be honest.

[Dave Burris]

Many delicate electronic devices use DC power, not AC like refrigerators and other household appliances. You will probably see a lot of Electronic items that have an adapter that you plug into an AC power outlet, but the device is running off DC power via the “transformer” which is actually a full wave bridge rectifier. (Typically 4 diode rectifiers in a circuit) DC power is better because it only moves in one direction and is a lot more predictable. Being that not all countries run on the same type of power or use the same color wires in the AC wiring, adapters can be made for electronic devices being shipped to different countries, it can be made to accept that country’s AC power and will always provide the correct DC power to their device.

You're sort of skipping over the fact that the "transformer" you speak of is only a part of the power supply. The transformer blocks DC, lowers or raises the voltage, and provides isolation from the incoming power source. Let's not forget that the building is also isolated via a transformer and the voltage lowered to a usable, and generally safer voltage. The entire function of the rest of the power supply is low pass filtering to remove noise and remove ripple, and in a regulated supply maintain a constant voltage within the current limits of the regulator.

Alternating Current- Dirty power is actually noise in the AC power lines, caused by electro-magnetic interference (EMI) and radio frequency interference (RFI). EMI is caused by electrical interferences from appliances, especially those that use motors (copying machines, air conditioners, refrigerators, washing machines and vacuum cleaners). RFI is caused by interference from radio devices such as cordless phones, microwave ovens, cell phones and others. The myriad electrical wires are usually not shielded and are affected by RFI and EMI interference. The solution is EMI/RFI filtering built into many power protection devices, which filters out noise in the AC power line and provides clean power to connected components.

Are you referring to noise induced into the building wiring? Perhaps you're referring to current modulation of the power, or turn-on/off transcients? Most power supplies in audio equipment already address much of this out of necessity form proper operation.

The best protection for equipment is a dedicated circuit within a building. How many places that you play have a dedicated circuit for entertainment only? Probably none. The best protection is an Isolation Transformer Line Conditioner. They are not terribly expensive anymore. Here is an example:

What do you mean by dedicated circuit? You mean a separate service feed from a dedicated transformer?

Tripp Lite® Isolation Transformers-Complete line isolation, noise filtering, and surge suppression offers 100% isolation from input AC line Isolation transformer design serves as an alternative to installing dedicated circuits and electrical upgrades. Remove EMI/RFI noise, utility switching transients, background spikes, and power problems generated by other on-site loads, utility grid-switching, and lightning related surges. Surge suppression components offer continuous line filtering of a full range of power line noise in all modes. Transformers feature NEMA 5-15P input and NEMA 5-15R output outlets. $164.44

Technically speaking, an isolation transformer does not do much in many of the areas you mention. An isolation transformer simply provides isolation from the power lines and blocks DC. Your build is already isolated from the outside lines in the same way.

It does appear that Tripp-Lite calls their isolation transformer-based power conditioners isolation transformers so I'll pass on commenting on this further.

The "standard" power conditions do not incorporate an Isolation Transformer and really don’t offer much protection for your equipment. Also, surge suppressors cannot respond quickly enough to “eliminate” a lightning strike that is close by. How much energy is in a lightning strike (rather than lightning between clouds that doesn’t hit the ground) is substantial. It can be 100,000,000 volts and a lot of heat to go along with it. I don’t know of any surge suppressor that can handle lightning strikes that are close by or hit your building. Lightning rods are a good idea. The best thing to do is turn off your equipment during an electrical storm, unplug it from the power outlet, and move the power cable far away from the wall outlet. In extreme cases, unplug all your equipment too.

While this is mostly true, are you claiming that the Tripp-Lite can protect against direct lightning strikes? You do seem to admit that NO suppressors can deal with this, and that's true.