BOOM BOX 2 - custom made Bluetooth Speaker - NEW verson


Somewhere in the list of topics in my website, I already show one self made battery driven Bluetooth Speaker with proper size.

Well, now is the time to to extend that a bit, and the new build use already two batteries, bigger amplifier and bigger speakers.

The amplifier, once again Chinese and use Bluetooth / 3.5mm jack as input source. The difference with previous one is the missing of SD card / USB reader.

The amplifier itself is based on TDA7498E chip and on paper it will be able to output about 150W@4ohm with 36V of power supply. The bridged mode will be of about 200W.. That is quite a lot for such a small foot print chip but let`s see.

[Read More…]

Friday, 1-July-2022

BOOM BOX - custom made Bluetooth Speaker


There are many ways to build own Bluetooth custom speaker box, and here in that article is my first attempt.

Used in the project:

- MDF 6 and 9mm

- full range speakers: 50mm@15W, twiters: 2cm@3W, bass: 9cm@35W

- amplifier , Milwaukee M18 battery holder, some wires …

- fun…

[Read More…]


Audi 80 Car sound project


Time to set some sound in one ancient vehicle produced by the Germans - Audi 80.

The project get some time and as final result can be described as.. working well

[Read More…]


KENWOOD car player - control from steering wheel

Hi there,
That DIY is dedicated to Kenwood KDC-6051U or how to use your steering wheel audio control buttons to take control over it.
Based on specs, the unit should accept commands on cable. That sound great, but there is bad news also - there isn`t any info about the protocol used(or at least I can`t find one). On the market there are products(of course from KENWOOD is the first option) that read your steering controls and put necessary codes to the unit. That cost about 60e for the box and 25e for cable in KENOOWD one, and little less for the other brands. That is quite a lot if the whole unit cost 170e.
From what I check on that “communication” cable constantly come +5V. There is no action if I tight it to pot and try different resistance. Well, obviously is not PIONEER/SONY way. My shot in the dark is that they use single wire protocol by pulling to GND that line in certain amount of time to generate start - 0 / 1 - end sequences, but to be sure I have to buy one ready and to check what is doing so it isn`t how will be for now.
[Read More…]


Punto mk2 188 ignition key switch ON/OFF radio

How to make the ignition key to switch off the power to the radio Как да направим контактния ключ да гаси касетофона[/b]

My friend`s punto got after market stereo but problem arise. Even switching off from the ignition key it was still with power on. I check some electrical diagrams and found that below: Приятел реши да смени касетофона на своето пунто 2 но се появи проблем - дори при изваден ключ, касетофона си остава включен. Порових малко за схема и намерих тази посочена по-долу:

As you can see the power supply and memory support supply are connected on same red-white wire - pin 4. The original unit has on/off control via blue-yellow cable pin 3. I cut the power cable on pin 7 and use micro relay(found in ebay) as switch, controlled by the pin 3 wire. Както се вижда от схемата, паметта и захранването взимат 12 волта от един и същ червен-бял кабел на пин 4. При оригиналното радио, изключването от контактния ключ се извършва чрез син-жълт кабел на пин 3. Просто срязах кабела към пин 7, и ползвам микро реленце(от ибей) като ключ управлявано от пин 3

fiatradio1.jpg fiatradio2.jpg


Xantia II - audio update/s

When I bought my Xantia few years ago, first thing I`ve done was to replace the head unit(old Sony) what previous owner used with Pioneer DEH-1500 and also the OEM speakers with Pioneer combined ones:
The unit choice was because the fact it has wire remote control. In other words - 3.5mm jack and easy way to connect your steering wheel sound control to it.
Replacing resistors on the OEM buttons and small mod on the tracks will give you chance to control your player. Even with that setup the car audio will be just fine.
Well, that was until this year. I decide to give little “boost” to the audio.
[Read More…]


Xantia II - steering wheel audio player PIONEER control

Sony or Pioneer have resistor based wire remote. And because I bought one PIONEER DEH with 3.5mm plug for wire remote I start that project.
Internet investigation give me the list of the needed resistor values. The work was to replace resistors and redesign little the track relation and.. to enjoy the feeling of not touching the stereo when driving.
Schematic is enough I think to get all idea

buttons-steering1.jpg buttons-steering3.jpg