Why do some speakers (or amps) take more time to start?

[vroad]

My AVR in living room (Denon AVR-X3800H) takes about 10 seconds to fully wake up and start making a sound. I hear a clicking sound from amp when it starts (Relays sound?).
My active speaker in another room (KEF LSX II LT) takes less to wakeup from standby mode, like 4-5 seconds.
Cheap computer speaker I had in the past take even less if I remember correctly.

I guess longer startup time of my AVR is for stabilizing power for its powerful amplifier module, but I can't find relevant info online.

 

[rationaltime]

Audio video receivers are more complicated than speakers.
It isn't just turning on power supplies. On waking up one loads
its software and runs start up tests before turning on the signals.
It is similar to starting up a phone or other computer.

 

[PureLIN]

My AVR in living room (Denon AVR-X3800H) takes about 10 seconds to fully wake up and start making a sound. I hear a clicking sound from amp when it starts (Relays sound?).
My active speaker in another room (KEF LSX II LT) takes less to wakeup from standby mode, like 4-5 seconds.
Cheap computer speaker I had in the past take even less if I remember correctly.

I guess longer startup time of my AVR is for stabilizing power for its powerful amplifier module, but I can't find relevant info online.

From my hack for get digital I2S from AVR (my AVR is SC-LX59), the AVR will have a lot of checking precoduer to start.
It contains two power part, a transformer and a SMPS, SMPS provide power for digital board, trans for all other parts.
SMPS is always on, transformer is controlled by a relay.
1. After push the power button, the relay will switch on, so trans power on, the controller chip will check if the trans is output power correct (in SC-LX59, it's a special 3v ac), if this not exists, the trans relay will switch off immediately, refuse to power up.
2. Then the DAC/AMP module is powerup, but the AMP is still not output since there are another group of relay, controller the speaker output channel.
3. Controller chip check everything is working fine (through a lot of error singals, they will become low if any error on AMP module. SC-LX59 will check DC leak, fan error, overheat, etc). If any error exists, there will be an error indication.
4. The relay on AMP will switch on, the audio now will output.
Beside this part, the HDMI also need some time to recognize, then the AVR can get the audio signal.
So the AVR is very complicated desigined to avoid any failure causing hazard such as destory the sepaker or causing fire.

 

[solderdude]

My AVR in living room (Denon AVR-X3800H) takes about 10 seconds to fully wake up and start making a sound. I hear a clicking sound from amp when it starts (Relays sound?).
My active speaker in another room (KEF LSX II LT) takes less to wakeup from standby mode, like 4-5 seconds.
Cheap computer speaker I had in the past take even less if I remember correctly.

I guess longer startup time of my AVR is for stabilizing power for its powerful amplifier module, but I can't find relevant info online.

It mutes for a time period determined by the designer ensuring one does not hear an unwanted 'sound' coming from the speakers.
For this device the manufacturer found the 10s to be the minimum required time (it probably is less than 10s).
For other devices it might be less than 1s.

 

[audio_tony]

I guess longer startup time of my AVR is for stabilizing power for its powerful amplifier module, but I can't find relevant info online.

Most (if not all) solid state amplifiers will work from the moment power is applied.

The clicking you hear is indeed relays, which are connected between the amp and the speakers.

With a few rare exceptions, solid state electronic devices will operate as intended within milliseconds of power being applied.
Car radios tend to come on immediately for example.
The electronics in your car are ready from the moment you turn the key, you don't need to wait for the ECU to 'warm up'.

The reason your AVR takes a few seconds longer than your active speaker, is probably because the manufacturer is playing it safe by giving all the other electronics time to stabilise (which will typically only take a few milliseconds), and avoid any nasty noises through the speakers.

I have built many power amplifiers, an during testing operate them without any protection circuitry or power on delays - and the very moment power is applied, sound comes out of the speakers.

 

[egellings]

Audio video receivers are more complicated than speakers.
It isn't just turning on power supplies. On waking up one loads
its software and runs start up tests before turning on the signals.
It is similar to starting up a phone or other computer.

You boot them up.