Amplifiers / receivers

How to buy an amplifier or AV receiver: stereo, valve, home cinema

Updated 20 October 2026

Stereo or multichannel sound

First answer the main question: what do you want to amplify? For two speakers and music, an integrated stereo amplifier is enough. For a home cinema you need an AV receiver with 5.1, 7.2 or more channels, Dolby and DTS decoders and HDMI inputs. Separate power amplifiers and pre-amplifiers are for those who build a system step by step, and valve amplifiers are for fans of a special sound who are ready to look after the valves.

Power and matching with speakers

It is not only watts that count: the amplifier must be matched to the speakers by impedance (4 or 8 ohms) and sensitivity. Power is quoted per channel and for a given load, for example 2×100 W at 8 ohms. An amplifier with headroom holds dynamics better at high volume. For a small room and sensitive speakers, a powerful unit is unnecessary.

Inputs and features

Make a list of your sources. For vinyl you need a phono input, for a TV an optical or HDMI eARC input, for streaming a built-in network module or Bluetooth. If you connect a turntable or CD player, make sure the input stage supports it. For receivers with HDMI, ask about the version (whether it supports 4K and HDR) and the number of inputs, so you don't have to pay extra for a splitter.

What to put in your request

• type: integrated stereo, power amplifier, AV receiver, valve, pre-amplifier;
• model: for example, Denon AVR-X1700H;
• new or used: and in what condition;
• power: per channel and at what impedance;
• number of channels: 2.0, 5.1, 7.2;
• inputs: phono, optical, HDMI 4K/eARC, Bluetooth, network;
• warranty, delivery, budget.

Example: “I need a used 5.1 AV receiver with HDMI eARC and 4K, 100 W per channel, for example a Denon AVR-X1700H, in working order with a remote. Courier delivery to Tsuen Wan, budget up to HK$2,800.”

How to compare offers

Look at what's in the box: remote, the microphone for automatic speaker setup, cables. For used units, ask whether the unit gets hot, whether there is noise or crackling from the potentiometer, and whether all outputs work. For valve amplifiers, ask about the condition and age of the valves: replacing them is not always cheap. A seller's warranty on technical condition helps a lot with expensive purchases.

How it works on BlaBlaPrice

You describe your task once on BlaBlaPrice. After the check, sellers of audio equipment see the request and reply in the chat: what exactly, in what condition, at what price, with what delivery. They see their place among the others and adjust their terms. The best offer by value is shown first, with seller reviews beside it. Contacts are hidden, and it is free for the buyer. Read more on the page about how the service works.

To choose speakers, look at speaker systems.