Audio splitter With Amplification

[LightShow]

Hey all

I have This small audio splitter which takes one single 3.5mm audio jack and then splits it out 5 ways allthough the output sound is low when all are connected at once.

i wanted to know if it would be possible to make a 5 way splitter with amplification so that all 5 outputs have a strong audio signal output from the device which preferably should be battery powered..

Let me Know Your thoughts
Regards, lightshow

https://www.amazon.com/6-Way-Stereo-Headset-Splitter-Headphones/dp/B00DQUU8T4

 

[davenn]

I have This small audio splitter which takes one single 3.5mm audio jack and then splits it out 5 ways allthough the output sound is low when all are connected at once

hi ya

what is the audio source ?

a phone or other MP3 player ?
is there still not enough volume even if the source volume is turned up ?

 

[LightShow]

hi ya

what is the audio source ?

a phone or other MP3 player ?
is there still not enough volume even if the source volume is turned up ?

the way i use this setup is usually with a laptop or phone connected to multiple headphones or speakers..
for small parties we connect 5 UE BOOM's to the splitter and play music that way allthough the volume difference is significant

 

[LightShow]

hi ya

what is the audio source ?

a phone or other MP3 player ?
is there still not enough volume even if the source volume is turned up ?

at full volume the splitter sounds like its running at around 60% of volume

 

[davenn]

at full volume the splitter sounds like its running at around 60% of volume

OK
Im thinking a small audio amp between the source and the splitter .. something based around an LM386 or similar

maybe eBay has ready made booster amps, try some searching

 

[LightShow]

OK
Im thinking a small audio amp between the source and the splitter .. something based around an LM386 or similar

maybe eBay has ready made booster amps, try some searching

would this work perhaps?

http://www.ebay.com.au/itm/1x-LM386...317561?hash=item1eba3903b9:g:qD0AAMXQ74JTR07U

 

[davenn]

would this work perhaps?

http://www.ebay.com.au/itm/1x-LM386...317561?hash=item1eba3903b9:g:qD0AAMXQ74JTR07U

yup, nice one, just remember you would need 2 of them one for each stereo channel .... maybe there's a stereo version board with 2 chips

not sure what other small audio amps there are out there, ... we need to keep your battery supply/portability in mind for anything suggested

 

[LightShow]

we need to keep your battery supply/portability in mind for anything suggested

i dont have a problem using one for each channel allthough im hoping it will all work via something like a 9v battery

 

[davenn]

i dont have a problem using one for each channel allthough im hoping it will all work via something like a 9v battery

will require something with a bit more guts than one of those. The 9V PP3 is for very low power consumption uses
depending on how long you want it to run for, either a NiCd, NiMH or LiPO types will be required

Dave

 

[LightShow]

will require something with a bit more guts than one of those. The 9V PP3 is for very low power consumption uses
depending on how long you want it to run for, either a NiCd, NiMH or LiPO types will be required

Dave

Something rechargeable would be better so maybe a LiPO Would suffice..
What Current\Voltage Should i be looking for?

 

[BobK]

A couple of comments.

LM386 is very old technology and not very efficient. There are 3W class D stereo amplifier available on EBay for a couple of bucks. This would be much better for your application. It would last twice as long on batteries, for example.

Also, if you are connecting 5 pairs of headphones in parallel, this may lower the impedance enough to give the amplifier problems. Assuming 32Ω, which is typical of earbuds, the impedance would be 6.4Ω which should be fine for the class D amps I am recommending. If the earphones are 8Ω, you cannot parallel 5 of them.

And one more thing. The LM386 has a minimum gain of 20dB. This is too high and will be driven into distortion by a headphone output. You would need to reduce the level with a divider. (this might also apply to the class D amps, not sure that gain they have).

IXP

 

[davenn]

LM386 is very old technology and not very efficient.

true
as I said there I wasn't sure what else is available

There are 3W class D stereo amplifier available on EBay for a couple of bucks. This would be much better for your application. It would last twice as long on batteries, for example.

got an example, please, so we are all on the same page

 

[BobK]

http://www.ebay.com/itm/PAM8403-3W-...746788?hash=item3f674889e4:g:9U8AAOSw-FZXkDWR

Bob

 

[LightShow]

http://www.ebay.com/itm/PAM8403-3W-...746788?hash=item3f674889e4:g:9U8AAOSw-FZXkDWR

Bob

using the suggested amplifier above I will need to regulate voltage for anything above 5v?

 

[Audioguru]

Your music source is designed to drive one pair of headphones, 5 in parallel overloads it which reduces the volume and causes distortion. You need to boost the current, not the voltage.

The ebay LM386 amplifier has a voltage gain of 200 (!) which is way too high. If you fiddle with its tiny parts then you can reduce its gain, but its minimum allowed gain is 9 which is still too high..

The ebay class-D amplifier also has too much voltage gain.

Since the amplifiers amplify their noise (hiss) then if you reduce the input level the hiss will be annoying.

 

[davenn]

http://www.ebay.com/itm/PAM8403-3W-...746788?hash=item3f674889e4:g:9U8AAOSw-FZXkDWR

Bob

cool, but I prefer this variation ... has a built in stereo volume control

http://www.ebay.com/itm/PAM8403-5V-...id=100623&rk=4&rkt=6&mehot=ag&sd=272315746788

using the suggested amplifier above I will need to regulate voltage for anything above 5v?

yes you will
Operating voltage: 2.5V-5.5V
with 5.5V being the absolute max
you could look at using say 3 x 1.2V AA rechargables or maybe a 3.6V LiPO style with appropriate charger

 

[Audioguru]

The PAM8403 amplifier has bridged outputs so the "splitter" cannot be used because it will short circuit the half of the bridged output of one channel to half of the bridged output of the other channel.

Also, the PAM8203 amplifier has a gain of 24dB (16 times) which is too high unless you turn down its volume control a lot.

 

[LightShow]

cool, but I prefer this variation ... has a built in stereo volume control

http://www.ebay.com/itm/PAM8403-5V-...id=100623&rk=4&rkt=6&mehot=ag&sd=272315746788

Believe it or not i actually have this exact item in my parts bin!!

 

[Audioguru]

For headphones you should forget about using this amplifier.

Note:
Left and right channel output of the "negative" can not be together, otherwise it will burn IC, and speaker(load) should be connected before power on.

 

[davenn]

AG is correct, so the search for something suitable resumes