Kitronik 3W Class D Stereo Amplifier

Hi - I would want the students to have the opportunity to swap out the green LED (provided) for other colours. Can you possibly list me the product numbers for RED / Blue / Yellow etc (5MM) direct replacement LED's that would not require any alteration to the resistance provided in the Amp kit... essentially straight swap LED's from your product range. Thank you . Do you also sell any alternate switch designs that work in the same way as the one in the kit (I assume they are ..charge from battery / off / charge from USB)... thank you, (just need this info to finalise my order)

You could swap the LED out for any of the following which are direct replacements and would need the resistor changing, 3504, 3506, 3567, 3543, 3542. The last two codes would only need a resistor value of 150 Ohm, however keeping the 220 Ohm resistor would be fine. With regards to the switch it is possible to swap this for a different one, however you would need to ensure that it has the same pins as the one supplied in the kit, here is a link to the datasheet, https://resources.kitronik.co.uk/pdf/3427_datasheet.pdf

Can this be used with 1 speaker?

Hi there, You could use it with one speaker but you would lose parts of the audio and quality of sound as the kit is set up to be stereo. best Regards Cullen

I have recovered 2 speakers from an old Coomber CD/Tape player. Each speaker is marked as 8 ohm 10w. Could I use this kit with those speakers, or is the 3w per channel output too low? Your High Power Stereo Amplifier kit outputs 15w per channel; would this be too high?? This whole speaker rating versus amp output thing is confusing!

Hi Paul, Hopefully I can help! Wattage is sort of an overall power indicator and you work it out by multiplying voltage by current (amps). So as long as your speakers have a higher wattage than the amplifier you should be fine on that front. So the 3W class D would work with those speakers but our high power amp is 15W so 5W too much for the 10W speakers to cope with. The Ohms are the impedence across the speakers. This is basically resistance. These circuits are twice the resistance of the normal speakers we supply so you would also get less power to those speakers than with our normal set up. I hope that all makes sense? Best Regards Cullen

could this be a guitar amp?

Hi David, You certainly could make a small amplifier for a guitar with this kit. Best Regards Cullen

Is there any way this kit can used with a solar panel & rechargeable batteries (similar to your 5v solar light kit)?

Hi James, In theory yes you could use the same set up to power the 3W Class D amp kit, however as this kit can draw up to 600mA you would only likely get around 2 hours of use from the batteries before they were flat. So although it would work it wouldn't be very practical.

I baught the kit and made it. The green light is on but no sound. I have looked through the troubble shooting guid but couldnt find a fix. Any ideas what might be wronge

Hello Ryan, I'm sorry to hear you are having problems with the kit, the best option if you have already been through the fault finding is to send a photo of the top and bottom of the circuit board to support@kitronik.co.uk with details of what the kit is/isn't doing and the power supply being used.

Hello, what is the individual frequency range of the audio drivers and the amplifier?

Hi Eugene, After checking the datasheet for the amplifier IC and the circuit design the frequency range of the kit is between 20-12KHz.

Hi I am a GCSE product design student and I am planning on buying this kit. I have one question however. Is it possible to connect the pcb in this kit to another pcb? I want the batteries to power the speakers but also another component at the same time and it is on a different circuit board. Is there any way I can do this? Thanks

Hi Hyder, You may be able to do this, however it depends greatly on what the other kit/component is you want to run from the same power supply. If you email support@kitronik.co.uk with the full details I will be able to check if this is suitable.

Hi can this kit be combined with the radio kit?

Hi Mark, although we haven't directly tried this our self it should be possible with a few slight changes. The audio out of the radio IC is a lot lower than a line signal, so you would need to use the on board amplifier as a pre-amp to get the output to about 1V. Follow the assembly instructions except don't add the speaker to the FM radio. Instead connect the audio connector signal wire to one of the speaker connections, it wants to be the speaker connection pin next to the speaker text. Then connect the ground on the audio connector to the negative power connection on the board. Set the volume fairly low and you're ready to give it a try

Could you connect the micro USB charger to this circuit so that is would be able to both charge an android phone and connect the music on the phone to the speaker?

Hi John, Unfortunately none of our amplifier kits allow you to charge your device while playing music to it. If you are referring to the Basic - LiPo Micro-USB Charger, this is only suitable to charge 3.7V LiPo cells via the JST connect on the board.

Could you connect the Apple 8 pin charger to this circuit so that is would e able to both charge an apple phone and connect the music on the phone to the speaker?

Hi Maddie, Unfortunately as per my previous answer this amplifier kit hasn't got the circuity built in to allow it to charge either a phone, IPod or MP3 player. Sorry.

Would this speaker circuit be able to be powered by your Polymer Lithium Ion Battery (3.7V, 1Ah)?

Hi Robert, You could use this to power the kit, however it is only likely to last maybe a couple of hours so before the voltage drops below the minimum of 3.2V’s.

I have never made anything electrical before and wanted to know if this set comes ready made? i.e the circuit board etc and just have to solder the other bits like in the other kits.

Hi James, The 3W class D amp kit comes with the circuit board and all the parts have to be soldered onto this. If you’re looking for a pre-built kit then the highest output amplifier kit that comes pre-built is the Deluxe amp kit, deluxe-stereo-amplifier-pre-built

Hi Can the LED / Slide switch / volume control be put on fly leads and placed in different positions ( I assume the USB charger is fixed to the board?).

Yes the LED switch and volume control are fine to be put on flying leads. As long as they are connected up in the same way as they would on the board then it will be fine. Unfortunately you are correct the USB charger is pre-mounted onto the board.

One of the answered questions confirms that you can add more than two speakers in parallel. Please could you advise if resistors need to be added when you do this, and if so what value? Thank you very much.

You would just need to check the speakers in parallel on each channel. You would need to make sure that the speakers you are using are 8Ohm’s, so when they are connected in parallel they give a 4Ohm load.

is the speaker good quality? and if so what decibels does it read?

The speakers on this kit are a good way to improve sound quality without a large price tag, as such they are good quality full range speakers. The only information we have regarding the decibel reading is the following, Mean sound pressure level: 86 dB (1W/1m)

does the 3w class D stereo amplifier kit support more than 2? how will 4 do? will it work?

Hi Nathan, do you mean can you have 4 speakers connected to this kit? If that’s what you mean you could connect 2 8Ohm speakers per channel in parallel which would give a 4Ohm load per channel which is what this kit is designed to run.

what is the radius of the speaker?

The diameter of the speaker including the metal frame is 65mm, as such the radius is 32.5mm.

How difficult would it be to add a bluetooth module and a charging lithium battery. Would it be as simple as wiring them into exisiting ports or would i need a lot of configuration?

None of our project kits have the facility to charge a device as this can be a very sensitive process. We don't currently make a bluetooth add on module, off-the-shelf modules do exist though and should come with instructions for connecting to an amplifier.

Could I exchange the Male 3.5mm Jack with a 1/4" Female Jack input?

Yes you can use a 1/4" Female Jack input instead of the male 3.5mm that is supplied with the kit, however we are not able to swap this with in the kit.

If i wanted this amplifier to run off mains power supply which power supply would i use and how would i connect it instead of the battery cage?

The 3W class D stereo amplifier kit comes with a pre-mounted Micro USB connector on the board, this means you can use a Micro USB power supply. The one we recommend using is the following 2208-5v-1a-micro-usb-uk-mains-wall-power-supply this will just plug straight into the connection that is one the PCB.

Would you be able to have 2 of these kits added together? So have 4 speakers with one 3.5mm stereo amplifier cable and one or two battery cases?

You would have to give it a try, but there is no reason why if you connect the three 'input' connections from one board to the other board that you wouldn't get them both producing the same audio. This wouldn't give you any better quality of audio, though the volume would be louder, or would be of benefit if you needed the speakers to be in a different place. If you are wanting to do this just to increase the volume then the 15W+15W high power amp might be a better option.

1. What's the sound quality like compared to the Deluxe Stereo Amplifier Kit? 2. Is it possible to wire in one speaker speaker instead of two as I am currently unsure whether my design will feature both at the moment?

Both the amplifier IC and the speaker used on the 3W amplifier is better quality than the deluxe stereo amplifier so naturally the sound quality is better on the more expensive 3W version. Yes you could just connect one speaker to the amplifier if you only want a mono amplifier.