What is RMS?
RMS stands for “Root Mean Square”, which is a fancy mathematical formula for finding the average amount of power an amplifier can continuously produce. There is no legal standard for calculating RMS watts for an amplifier, but our amplifiers are tested by the Underwriter’s Laboratories (UL) to obtain a true RMS power rating.
“Phantom Power,” “Headroom?”: What are they talking about?
Though Phantom Power might sound like a superhero’s catch phrase, it isn’t. Phantom power simply powerst the preamp of a condenser microphone. Many powered misers feature phantom power so users won’t need to rely on addiitional batteries or power
sources. While phantom power functions ideally on condenser mics, and unbalanced dynamic mic can be damged. So, do not turn phantom power on unless a mic that needs it is connected to the mixer.
Headroom is a concept that refers toa system’;s (amp, mixer, etc.) dynamic range, or nmormal working volume. Headroom refers to an average (in decibels)between the normal volume of a system and the volume at which it starts to distort. Basically that means if you have a system that sounds good at +6db and distorts at 18dB, that system has a headroom of +12dB. Knowing how much headroom your sytem has will allow you to use to its full capacity without damaging it.
What is impedance and whay does it matter?
In very simple terms, impedance is the ability to resist electrical power. Impedance is measured in Ohms. The lower the impedance, the more power the system will accept (because the resistance is low). Speaker cabinets are generally rated at 8 Ohms. If you plug them in to each other the Ohms are cut in half, and become 4Ohms. This is because two speakers resist power half as much as one speaker. Power amps are sometimes rated at 4 Ohms, because it is expected that you will use two 8 ohm speaker cabinets. A 100 watt (@ 4 ohm) amp will give each speaker about 50 watts. But , what if you only plug in only one (8ohm) speaker., will it get all 100 watts? No, because the impedance is double then the watts are cut in half, the single speaker will only get 50 watts. Never go below the minimum impedance of an amplifier. It can cause serious damage to the amplifier. So, don’t try to plug 8 speakers into your 100 watt amp to get more power, because it’s a trick you can only try once.
Hi-Z versus Lo-Z cables
Microphone cables are often available as Lo-Z or Hi-Z and each type is used in different circumstances. Lo-Z cables have a female and male XLR connector while Hi-Z have a female XLR and a 1/4" connector. Lo-Z cables are used for most microphones and newer electronic devices. Hi-Z cables are used for older equipment and electronics with high impedance. Additionally, Lo-Z cables are typically used for microphones with less than 600 ohms of output impedance. Hi-Z cables are used for devices with 5,000 ohms or more output impedance.
What’s the difference between speaker and instrument cables?
Instrument and speaker cables often look the same, but have a few things that make them very different. The basic difference between th two is that an instrument cable has extra insulation and shielding that you do not find a speaker cable. The extra shielding keeps other signals from interfering with the sound of the guitar. These signals include anything from radio signals to static electricity. Because the signal coming from your guitar is not strong , these small signals could have a big effect on the sound. Speaker cable delivers a very strong signal from the amplifier. This signal overpowers any radio wave and does not need the extra shielding. Because the signal is so strong, the speaker cable needs thicker copper wire to handle the excess energy. Below is the recommended speaker gauge that corresponds with the wattage of an amp.
Watts Gauge Max. Length
| Watts |
Guage |
Max Length |
| 0-100 |
16 |
50'
|
| 0-100 |
14 |
75'
|
| 0-100 |
12 |
100'
|
| 100-400 |
16 |
20'
|
| 100-400 |
14 |
50'
|
| 100-400 |
12 |
75'
|
| 400+ |
14 |
20'
|
| 400+ |
12 |
50'
|
- Information sourced from The Music Link Inc.
|
