GOTTOMIX HA1800 is a full-featured 18-channel stereo headphone amplifier with 6 auxiliary inputs, which can allow separate mixing in each headphone channel. Each output channel also has a dual balance control feature, that is, it can position the sound image between the left and right channels of the main signal bus, or change the mixing between the main signal bus input and the auxiliary signal input for each channel.
Each output channel contains a stereo 1/4-inch TRS headphone jack on the front panel, and two stereo 1/4-inch TRS headphone jacks on the rear panel. This is to improve installation and quick patching capabilities. Mono, mute left and mute right for each channel can be selected in four different working modes: 1）Stereo 2）Mono left 3）Mono right 4）Mono（Left & right）In this way, multi-function monitoring can be realized, and the independent output level control of each channel can realize the personalized monitoring level.
With XLR and 1/4-inch TRS balanced input options, matching ”THRU” sockets can bridge multiple units. With the addition of a 1/4-inch stereo TRS DIRECT IN socket on the front panel, you can quickly patch and insert any stereo audio source prior to the input signal on the rear panel. The master volume control sets the main signal bus level. An 8-segment precision LED level meter detects the main signal bus. The 4-segment precision LED level meter displays visible feedback of all key directional signals of each output channel.
Front panel
DIRECT INsocket
The front panel 1/4- INCH TRS DIRECT IN is unbalanced stereo input. When used, it will take priority over the rear panel''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''s balanced input. This input is very useful when you want to temporarily insert a different main input signal from the rear panel input connection, or you can easily connect an unbalanced TRS type to another headphone output
Master volume control
This control adjusts the main signal bus level. The 8-segment LED level meter measures the audio level of the main signal displayed by the main volume control on the left.
MuteL, MuteRAnd mono switch
The switch sets one of the three working modes of stereo headphone output.
（This will only affect the headphone output and（Rear）The balance/mixing, level control section.）
1 ）All switches are not pressed = stereo output
2 ）Left channel mute pressed & Right channel mute not pressed & Mono pressed = Right channel mono
3）Right channel mute pressed & Left channel mute not pressed & Mono pressed = Left channel mono
Stereo auxiliary input socket
Stereo TRS socket can directly insert stereo signal to a separate headphone channel. When the plug is inserted into an AUX input socket, the function of the balance control of the specific channel is changed, turning it into a hybrid control, adjusting the stereo AUX input and main signal between the channels Mixing of bus inputs.
Output socket
This stereo TRS 1/4-INCH socket can be connected to each stereo headphone output of the 6 output channels or another headphone distribution amplifier. Each channel on the rear panel has two identical output jacks.
Balance control
This control has two functions, one is without plug insertion, the other is with plug insertion, depending on whether a plug is inserted into the stereo auxiliary input as a specific channel.
No plug is inserted into the auxiliary input socket to control the left and right balance of the main signal bus supplied to a certain channel
A plug is inserted, and the control changes its function to change the mix of the stereo signal from the main signal bus and the stereo signal from each auxiliary channel. By supplying the return signal to only sing into the auxiliary input for a particular musician’s microphone, you can use the balance control as "MORE ME" to control the change based on the mix between the microphone alone and the main signal bus audio, which is composed of different microphones. The single-mix signal control of the balance control, this effect is only heard in the specific channel of the specific earphone.
Level control
This control changes the audio output level supply, which is the 1/4-INCH stereo output sockets on the front and rear panels of the respective channels. The 4-segment LED level meter is located at the switch position above each channel and displays the output level of each channel.
switch
This rocker switch controls the power switch. A small LED indicator lights up, indicating that the power is on.
Back panel
Back panel
Balanced main inputThru
XLR,1/4 –INCH TRS active balanced input socket, can be used for LINE signal input. The gain sensitivity is the same, the signal is supplied to the main signal bus (Note: The front panel DIRECT IN JACK has priority to these inputs when in use)
balanceThru
XLR, 1/4-Inch TRS JACK is fixed to the corresponding main balanced input socket. The main balanced THRU socket is useful for linking multiple HA-1800s together.
Stereo headphone output
These stereo TRS Jacks are the main output of each channel. These are connected in parallel to the corresponding front panel output sockets through lines. Either the front panel, the rear panel, or the front and rear panels can be used at the same time as a driver or as an additional headphone amplifier for multi-audio distribution link.
Note: Gottomix HA1800 has been optimized to drive typical headphones, impedance 32 Ohms to 600 Ohms. It cannot be used to drive a total impedance lower than 16 Ohms, but it can work but will not be damaged, but it will limit the maximum power output and may occur The wave-cutting distortion depends on the output level and load. When multiple headphones are driving from another headphone amplifier HA1800 (parallel), the available power will be distributed to different headphones, because it is the combined total load output, through the initial The chopped signal may become limited. Most modern headphone amplifiers require milliwatts of power to achieve full electroacoustic output in the middle-high order, so there should be few such problems. If there is a problem, simply Reduce the level or reduce the total number of headphones on a specific channel to increase the total load.
There is no direct relationship between the headphone load and the maximum sound pressure level output. The relevant specifications depend on the sensitivity of the electroacoustic output of the headphone amplifier, etc. What sound pressure level will broadcast a given level of input signal? Usually the rated power is 1mW, the sensitivity depends on Based on the overall design and the structure of the converter. Generally speaking, the power requirement should reach nearly 1/1000 TH equivalent to the power amplifier requirement to drive the speaker. Therefore, the power level that a typical headphone amplifier can provide is in the range of 10mW to 20mW, in order to achieve a very reasonable The sound pressure level output. Even 8 Ohm earphones can be driven to reach full sound pressure level and output through HA1800M. If there is enough sensitivity, regardless of the actual voltage output swing, it will be limited because of the overload protection circuit.
operating
Before starting, set the master volume control and level control of all channels to the counterclockwise direction. Set the balance control at 12 clock position. Set the mute and mono switch at the ”OUT” position.
Use a suitable balanced or unbalanced cable, (unbalanced cable should also be used for the rear panel input work, but with a remote control may increase noise), connect the rear panel balanced main input to the audio monitor signal source and assign it to the headphones. Or choose to connect The audio signal to the DIRECT IN socket on the front panel uses a stereo TRS 1/4-INCH plug. If you want to connect multiple HA-1800 to the same audio monitor signal source, it is very simple, serial link these hosts through the balanced main input connection. (Note : The serial link is only suitable for the rear panel connection. The DIRECT IN plug on the main panel can only be directly supplied to its respective HA-1800 main unit) Connect headphones, or connect another headphone amplifier (like GOTTOMIX AMP4) to the headphone output Front panel or rear panel,（Or front and rear panels）Use the stereo 1/4-INCH TRS plug. If you use the HA1800 auxiliary mixing function, use the 1 / 4” jack to connect the stereo signal mixed into an independent output channel to the corresponding auxiliary input interface.（Note: Use the TRS plug for mono signals to connect Tip and Ring together, or use the buttons on the front panel to create a mono output to the headphones.）The auxiliary input signal will be output only on specific channels according to the settings of the BALANCE and LEVEL control. Turn on the power switch and connect the audio monitoring source, and increase the master volume control during the broadcast to achieve the master volume control. The LED curve display table has readable information. If the green and yellow LED lights are particularly bright, the red light display has been avoided. Wave signal. This can ensure that a strong signal is available, which can be used to drive each of the six channels, and each subsequent amplification channel can work with minimum gain (the lowest setting of each channel level control), so To optimize their signal-to-noise ratio on the headphone output.
The next step is to set the level control of each channel to a level that can be heard comfortably, as a special earphone use
Note: When using an auxiliary mixer to add a kind of direct music signal to a separate headphone channel, in order to enhance the mixing of special music signals (PROVIDING”MORE ME”) for the channel that someone is listening to, The relative phase of the signal from the stereo auxiliary input will depend on whether it is the addition or subtraction of the auxiliary signal. The "MORE ME" effect will only occur when the two signals are added. If they are opposite (180 degrees are not in phase Inside), the stereo auxiliary input is actually subtracted, beyond the mixing is not reflected in a channel of the headset. Most consoles and microphone preamplifiers will have a phase inversion switch, with this you can set your Desired mode of operation.
Specification:
Input connection: XLR (female) balanced (2), 1/4-INCH balanced (9)
Output connection: XLR (male) balanced (2), 1/4-INCH balanced (2),
1/4-INCH stereo headset (18)
Input impedance: 40K Ohoms main
10K Ohms straight
15K Ohms auxiliary input
Output impedance: 32-600 Ohms headphone
Maximum input level: +21dBu (all channels)
Maximum output level: 150Mw (600 Ohm headphones)
500Mw (32 Ohm headphone)
Maximum gain: 22Db.
S/N Ratio:>90db Typical
Total harmonic distortion: <0.01% Typical
Dynamic range:>101Db Typical
Common mode rejection >40Db
Phase shift < 10 degrees, 20Hz-20KHz
Power requirements: 120VAC/60Hz, or 230VAC/50Hz, 15 Watts
Size: 19”X6”X1.75”(483MM WX152MM DX44.5MM H)
Weight: 5.3lbs. (2.4kg)
Related: 0dBu=0.775VAC RMS
Now, BEHRINGER Behringer HA4700 and HA8000 headphone splitters have now withdrawn from the market. This Gottomix HA1800 will become its replacement and will surely occupy the market of high-end headphone splitters!