I connect my Harbinger LvL 12 Channel unpowered mixer MAIN OUT, to a pair of Alto Professional TX310 350W 10-inch Powered Speaker INPUT (as shown in the diagrams below). I'm using a pair of 1/4" to XLR cables but I'm getting a heavy buzzing sound on the speakers.
Without any input signal on the mixer and at 0db, I'm still getting a hum -However, if I use my iPhone and connect it directly to the speaker there is no hum, if I connect a CD player directly to the speaker there is no hum. I also noticed that from the Harbinger mixer "phone" (headphone jack) there is no hum.. and if I bypass the harbinger mixer and go directly from my Pioneer/Serato Mixing board output to the speaker .. no hum..
From the speaker's documentation - The speakers are expecting a "Line Level" Signal .. it seems like the Harbinger mixer "MAIN OUT" or CTRL RM OUT, it's not delivering a "line level" signal.. The hum sounds like an old guitar tube amp with defective capacitors. Is there any diagnostic checks for the Harbinger Mixer?
This mixing console is designed primarily for a sound reinforcement or “live sound” application. Mixer input channels feed the main fader, and that feeds the main outputs. Typically your main outs will feed an amp that drives your main house speakers (Floor Speakers).
The control room circuit, which includes the control room out jacks and the headphones jack, has some flexible functionality as far as it’s source or sources for you as the console operator to be able to monitor some different signal paths independent of the main mix outputs…OR you can monitor the main mix.
The control room outs are for connecting to the inputs of your monitor amplifier, so you can control volume without affecting the level of signal going out the main outs at the same time - such that you run you mix into you DAW (Digital Audio Workstation eg garage band, avid pro tool) or Recording Device - and then monitor it on your NearFileds and Headphones
The control circuit has a switch to source the main mix, or the cue mix. And then you have an analog two-track return, and that can be assigned to the main mix, or assigned to the cue buss and monitored by the control room circuit, and additionally you have a digital return with the USB input and that can be assigned to the main mix, or assigned to the control room circuit directly, independent of the position of the control room source switch.
Alto 10" PoweredSpeaker
- Powerful PA System Sound – 2-Way 350-Watt Class D power amplifier; newly designed horn delivers stellar coverage at 90° H x 60° V. Designed and tuned in the USA
- Driving Bass, Pristine Highs - 10-inch (254 mm) LF driver, 1.5-inch (38.1 mm) voice coil; 1-inch (25.4 mm) titanium diaphragm HF compression driver
- Setup Simplified - Lightweight, PA cabinet design for easy transport, set up and installation; Suitable for pole-mounting or use as a wedge monitor
- Connectivity Covered - Balanced XLR Mic/Line input, Link Output and Volume control; integrated analog limiter and overload protection circuitry
- Versatile Performance - Perfect for Mobile DJ’s at Weddings and Parties, Small Venues, Band Practice, Community and Sports Events, Ceremonies, Conferences and Spoken Word Performances
A Line In is much higher level signal, designed for powered electronic devices to send signals to each other. So, for example, you might plug a CD player into a mixer using the Line Ins. In pro equipment, a Line In can be an XLR input, a mono quarter-inch (6.35mm) TRS input, or maybe a mono eighth-inch (3.5mm) TRS input, although that’s less common. On consumer electronics, a Line In will probably be an RCA input.
An XLR is a kind of plug. It’s used on some microphones.
These are the two ends of an XLR microphone cable. The one on the left connects to the microphone, the one on the right connects to a mixing desk, amplifier, or computer audio interface. The back of the microphone looks like the one on the right; you can connect two cables end-to-end if you need a longer one.
They have very secure clips so they won’t fall out by accident; the tab sticking out of the plug releases the clip so you can disconnect it.
The three pins are positive, negative and ground. The signal is measured between positive and negative, ignoring ground, which is called ‘differential signalling’, and reduces noise. You can, however, make a cable that will feed a non-differential ‘single ended’ signal into a differential input, by connecting negative to ground.
These can supply power for microphones and preamplifiers; that’s called ‘phantom power’, and is a 48V supply between the two active pins.
To use one, you need the right kind of audio interface, and if the microphone needs phantom power that needs to be switched on.
Interfaces and mixers have two reference signal levels, one for microphones and one for powered devices. These will be labelled either ‘mic/line’ or ‘pad’; you want it in mic position or with pad turned off to use a microphone.
The same connectors are used for some other applications; certain kinds of theatre lighting system use these for control bus connections, for example. Logical, because a theatre will have large numbers of XLR cables and a supply of spare parts for them.
