How to connect the rear amplifier?

                                               How to connect the rear amplifier?

Power amplifiers are generally divided into front-level power amplifiers, rear-level power amplifiers and combined power amplifiers (commonly known as combined machines). A combined machine is a machine that integrates the front stage and the back stage. The front stage is used to initially amplify the signal and adjust the volume; while the rear stage is to amplify the signal from the front stage to drive the speaker. In the case of the same level, it is definitely better to separate the front and rear stages than the combined machine, because each has more space to make more precise. There is also less interference between the two, and more details.

Many people think the power amplifier is complicated, but in fact it is very simple. For example, the super sound power amplifier can be seen from the back at a glance. It is divided into 7 areas, that is, there are 7 amplification channels. The signal from the front stage is connected to the On the upper interface (RCA or XLR interface), it will be amplified after walking in a circle, and output to the speaker from the lower binding post. It is only responsible for amplification, one in and one out, there is no distinction between channels.

picture

Other multi-channel post-stages are similar and not complicated.

There are two advantages to separating the front and rear stages: First, there are more choices. By changing the front stage to play different sound styles, the playability is higher; Almost, it will become obsolete after a few years, and the latter stage can be used forever, so the cost of upgrading is relatively small.

In short, if you want to play a real home theater effect, sooner or later you have to go to the power amplifier.

The post-stage wiring to be mentioned below is mainly divided into three situations:

1. Pure pre-stage connection pure post-stage power amplifier method;

2. The method of connecting a combined machine with a pre-stage output interface to a pure post-stage power amplifier;

3. The method of connecting a combined machine without a pre-stage output interface to a pure post-stage power amplifier.

1. Let me talk about the connection of the pure pre-stage to the post-stage.

Have you seen the bottom row of balanced output interfaces (also called XLR or XLR), if there are, we give priority to using this interface, which has strong anti-interference ability and better output quality.

Carefully look at each interface has a corresponding channel name, such as SURROUND L, which is the left surround channel, connect to any channel of the rear stage, and then connect the speaker cable of the corresponding channel.

FRONT R (front right channel), FRONT L (front left channel), CENTER (center channel), SURROUND R (right surround channel), SURROUND L (left surround channel), SURROUND BACK R (surround back right channel), SURROUND BACK L (surround back left channel), HEIGHT1 R (overhead right channel), HEIGHT1 L (overhead left channel), HEIGHT2 R (overhead right channel) , HEIGHT2 L (left rear overhead channel), SW (bass channel), the active subwoofer does not need to be connected to the post-stage, it is equivalent to its own post-stage amplifier.

It should be noted that there are two types of input interfaces in the high-end rear stage, balanced and unbalanced, and there will be a toggle switch on it, which needs to be adjusted to the corresponding position.

After the front and rear signal lines are connected, don’t forget to connect another linkage control line. Generally, multi-channel home power amplifiers will have a linkage control function, and a 3.5mm male-to-male trigger signal line as shown in the figure below (some are triggered according to the signal on and off, so you don’t need to connect it separately).

One end is connected to the 12V trigger out interface of the AV front stage, the other end is connected to the trigger in interface of the rear stage, and the linkage switch on the rear stage is turned to the trigger position, and the front and rear stages can be linked to switch on and off without additional manual operation. level switch.

2. The second case is that the combined machine with the output interface of the pre-stage is connected to the post-stage

In this way, it can make up for the weak thrust of the low-end integrated power amplifier and squeeze out its pre-processing capability. The connection method is very similar to the pure preamplifier above, but generally there is no balanced output, and the only option is to use the RCA lotus socket, and there is no major problem in short-distance transmission in the home environment.

First find the PRE OUT (pre-stage output) area on the buttocks of your power amplifier, connect the corresponding channel to the post-stage with a high-quality, well-shielded audio signal cable, and then connect the post-stage speaker terminal to the corresponding channel, and finally don’t forget Connect the connection line.

3. The combined machine without the output interface of the pre-stage is connected to the post-stage

Here comes the problem, most of the low-end series integrated power amplifiers do not have pre-amplifier output interfaces, what should I do if I want to play with the post-amplifier?

In fact, there is also a way, which requires a certain amount of hands-on ability (if the hands-on ability is not strong, you probably wouldn't have thought of this kind of gameplay...).

It is necessary to disassemble the power amplifier, find the line of the output part of the pre-stage, connect the lead wire, and then disconnect the amplifier module inside the machine. This requires an understanding of circuits, and it is best to have after-sales maintenance manuals or circuit diagrams.

There are refitting kits and even refitting services on the Internet. Of course, this is risky. If the operation is not done properly and smoke comes out, the consequences can only be borne by yourself...

After refitting, just connect each channel in turn as mentioned above.

After connecting to the post stage, the level gain will change, and the sound style may also change. It needs to be re-adjusted and calibrated again, and then you can start to enjoy the extremely fast and shocking experience brought by the "turbo boost".