Is this by chance for something like a Language Studio?Hi,
I am building a 7 input to 8 output (headphone) mixer circuit. I finish on the design for the mixer circuit. The problem is I want to seperate 1 output to 8 output headphone jack. Can anyone give me some idea on how to do it?
Thank you. The sound is mono
You don't need to match the impedances at all. The output impedance of the amplifier needs to be as low as possible, for a good damping factor.My 0.02c If it's low volume (i.e. office headphone levels), you don't need to 'match impedances' so much,
I doubt it, the minimum specified impedance on the datasheet is 4Ω.a 386 will happily drive a fraction of ohm.
Damping factor is well important, if the damping factor is naff, you can "hear the sound of the speaker instead of the music", if you know what I mean.The output impedance of the amplifier needs to be as low as possible, for a good damping factor.
A "4 ohm rated" amplifier will drive a lower ohmage, provided the output level is lower than normal. Provided the package power dissipation of the IC is not exceeded, it'll be OK. After all the amplifer is just a power supply with a variable output voltage. In practice you can have a shorted speaker to an amplifier and the amplifier won't blow up until the user turns up the volume high to compensate for the low sound.The amplifier also needs to be able to drive the minimum impedance you plan on connected to it.
<..> the minimum specified impedance on the datasheet is 4Ω.
Doesn't matter for headphones, they are designed to be fed from a high impedance source, pretty well every headphone socket on every piece of equipment is simply fed from a resistive attenuator.Damping factor is well important, if the damping factor is naff, you can "hear the sound of the speaker instead of the music", if you know what I mean.
Good point. Speaker has rather a lot of moving mass needs damping.Doesn't matter for headphones, they are designed to be fed from a high impedance source, pretty well every headphone socket on every piece of equipment is simply fed from a resistive attenuator.
Don't confuse speakers with headphones.
The circuit is on the datasheet which can be found using Google.Thanks for all the reply. How do I design the circuit? I need the circuit before I go and buy the headphone.
do you want to connect 8 headphones to the same output, or is it 1 headphone to 7 inputs, or is it 7 headphones to 8 outputs? Please tell us more..
Hiya, at this moment in time I,m here in sunny Gran Canaria (using a different keyboard layout) so please excuse any weird spelling mistakes you seewhich is the best, if the circuit will be used in language studio...
and how can I do that... please help.
im planning to built a language laboratory.. !
As already discussed way back in this thread, you don't connect the headphones directly to the amplifier - you feed each one via it's own series resistor.1. just measure the ohmage of one of the headphones (32 ohms typical) and divide it by the number of headphoñes, say 32 / 16 = 2Ohms. (don·t forget that 8 headphones have a total of 16 speakers, a L & R for each head) So in my example here, I need an amplifier that is happy driving 2 Ohms.