Usb powered headphone Amp

After the successful build of my gaming amp i decided to try a usb powered headphone amp. So i came up with this design after having “reversed engenierd”  a cd rom which had cd playback capaility. i the added an input section. after acquiring the pdf datasheet for the ic i then added the usb power. after a few tries found out it needed a pull up resistor to unmute the circuit. here is a pic of the hacked up version.

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After a couple hours of use i then took to make a schematic and pcb lay out and came up with some modifications that added a bit more low end and less noise all in all i love this amp more and i am planning on a mark2 for. ..you guessed it gaming purposes. here is the schematic and pcb layout.

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And heres  the pcb
Continue reading Usb powered headphone Amp

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Fritzing Project – Mono Audio Amp – Headphone Amplifier

After using eagle i wondered if there was any software that would turn a breadboard project into a schematic, a quick Google Search came up with this. Fritzing, a new app i have found very useful. It in fact turns you breadboard project into a schematic and more. With a couple of clicks and some patience you can turn your breadboard into a full blown PCB project. Check it out!.ImageThis little mono amp Project came to be after loosing  some lm386 ic’s. No need  to fear the JRC386D is here! it is quite simple build. but with that simplicity came some unfortunate drawbacks. An unexpected hum-noise combination was affecting the circuit but was remedied by adding c1 – c3 to the input line practically removing the hum and noise completely. I had seen many schematics place the L.E.D right after the battery or switch, which would still light up even if there was an error after along the way ie. even if the IC1 was “busted” . I placed the L.E.D after IC1, squiring power from Pin 5 thus letting  us know that power was being fed to IC1 and that if there where any problems they would be after the JRC386D IC. Fritzing did not have a Mylar Capacitor option so i then used tantalum capacitor and re-labeled it to MC1 and MC2 and you can see on the schematic notes. RC2 is a trim pot that allows “bass” into pin 7 or Bypass on the JRC386D. Still  dont know if that is the correct way to add bass control. Please note that The JRC386D is a single channel IC, but i have wired it to take stereo in signal and output a “fake – Simulated stereo” out signal, since they are both merged into the IC. I know its not the best “but it works”ImageAs you can see this software allows to add custom artwork, something i still cant figure out how to get working on eagle. I had made a “mock” logo for my work so i added it here. all in all i have come to like this software which is easy to use and not hard to learn. This is in fact  my first project with Fritzing which only took roughly 3 hours to complete this whole setup after only had “played around with the software 35 min after having downloaded it.  ImageHere is a complete parts list. unfortunately the component values don’t show on schematic.

Assembly List

Label Part Type Properties
Batt Battery block 9V voltage 9V
C1 Electrolytic Capacitor package 200 mil [THT, electrolytic]; capacitance 1µF; voltage 16V
C2 Electrolytic Capacitor package 100 mil [THT, electrolytic]; capacitance 220µF; voltage 16V
C3 Electrolytic Capacitor package 100 mil [THT, electrolytic]; capacitance 10µF; voltage 16V
C4 Electrolytic Capacitor package 100 mil [THT, electrolytic]; capacitance 1µF; voltage 6.3V
C5 Electrolytic Capacitor package 100 mil [THT, electrolytic]; capacitance 47µF; voltage 16V
C7 Electrolytic Capacitor package 100 mil [THT, electrolytic]; capacitance 47µF; voltage 16V
IC1 DIP – 8 pins package DIP (Dual Inline) [THT]; hole size 1.0mm,0.508mm; true; chip label IC; pins 8; pin spacing 300mil
INPUT Audio Jack (TRS) 3.5mm package 4Ucon 08780 [THT]; channels Stereo (TRS); size 3.5 mm
LED1 Red LED – 5mm package 5 mm [THT]; leg yes; color Red (633nm)
MC1 Tantalum Capacitor package 200 mil [THT, tantalum]; capacitance 47µF; voltage 16V
MC2 Tantalum Capacitor package 100 mil [THT, tantalum]; capacitance 103µF; voltage 16V
OUTPUT Audio Jack (TRS) 3.5mm package 4Ucon 08780 [THT]; channels Stereo (TRS); size 3.5 mm
R2 1k Ω Resistor package THT; tolerance ±5%; bands 4; resistance 1kΩ; pin spacing 400 mil
R3 Trimmer Potentiometer package THT; size Trimmer – 6mm; track Linear; type Trimmer Potentiometer; maximum resistance 10kΩ
S1 Toggle Switch package THT; switching circuit SPDT
Volume Rotary Potentiometer (Small) size Rotary – 9mm; track Linear; type Rotary Shaft Potentiometer; maximum resistance 10kΩ

Shopping List

Amount Part Type Properties
1 Battery block 9V voltage 9V
1 Electrolytic Capacitor package 200 mil [THT, electrolytic]; capacitance 1µF; voltage 16V
1 Electrolytic Capacitor package 100 mil [THT, electrolytic]; capacitance 220µF; voltage 16V
1 Electrolytic Capacitor package 100 mil [THT, electrolytic]; capacitance 10µF; voltage 16V
1 Electrolytic Capacitor package 100 mil [THT, electrolytic]; capacitance 1µF; voltage 6.3V
2 Electrolytic Capacitor package 100 mil [THT, electrolytic]; capacitance 47µF; voltage 16V
1 DIP – 8 pins package DIP (Dual Inline) [THT]; hole size 1.0mm,0.508mm; true; chip label IC; pins 8; pin spacing 300mil
2 Audio Jack (TRS) 3.5mm package 4Ucon 08780 [THT]; channels Stereo (TRS); size 3.5 mm
1 Red LED – 5mm package 5 mm [THT]; leg yes; color Red (633nm)
1 Tantalum Capacitor package 200 mil [THT, tantalum]; capacitance 47µF; voltage 16V
1 Tantalum Capacitor package 100 mil [THT, tantalum]; capacitance 103µF; voltage 16V
1 1k Ω Resistor package THT; tolerance ±5%; bands 4; resistance 1kΩ; pin spacing 400 mil
1 Trimmer Potentiometer package THT; size Trimmer – 6mm; track Linear; type Trimmer Potentiometer; maximum resistance 10kΩ
1 Toggle Switch package THT; switching circuit SPDT
1 Rotary Potentiometer (Small) size Rotary – 9mm; track Linear; type Rotary Shaft Potentiometer; maximum resistance 10kΩ

I have included a PDF PCB Layout if you wish to download it.New Amp V3_etch_copper_bottom

Diy pedalboard with mic stand

I recently had the urge to make a pedalboard. i hadseen the aluminum ones around but never really grabbed my attention, until now. it has come to me that i could set all knds of settings and extras that a normal off the shelve pedalboard will not have.

I have thought long and hard of what they migjt be, but most of all what intrieges me is the satisfaction of knowing that it will have the accesories that i need and most pf all want in a pedalboard.

Here are a couple of pics of the project, it is still not finished. needs wiring, some components and its enclosure.

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Headphone-Mix amp Gaming version

Ever wanted a gaming mix amp? well i did and i was asked to fork over 170+ Dollars. in the end i thought to myself, hey i can build of of these, how hard can it be. well now i want to share my journey with you.

this build has two sections, i guess. first is inputs to mix (not shown in pics) which then goes into amplification. obvious of course. the good stuff seems to be your getting what i think is a versatile unit. main purpose is for gaming mix amp which has line input (rca), mic, headset and also stereo 3.5 jack.

the amp section is based on a couple lm386 designs which i stripped down and modified so suit this application. it runs of a single 9v battery and currently in testing phase with usb power. usb power creates a large amount of hum and ticking noises which are not remedied by capacitor or voltage regulator. any ideas would be of great help.

what do you think?

I will be posting my schematics and pcb designs so they can be scrutinized. hope you guys contribute and share some ideas.

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Still need to get to the led bar but we need some extra ic chips to get the vu meter working. any ideas?

Update: 3-28-2013

here i show you my schematic for the diy gaming headphone amp.

Schematic
Schematic
gaming mix amp v2
gaming mix amp v2

here is the pcb layout.

imagination is key!