hi, im new to the forums here and recently i find myself in need of a 2.1 channel amp to run some satelite speakers and 2 subs for my bedroom. i did some searching and couldnt find a "premade" amp that fit my power needs for the subwoofer channel. i found this on ebay:
New TDA7294 2X80W 160W Subwoofer 2 1 Channe L Board Brandnew | eBay
it states that i will need a power supply. i read a few articles on here about choosing a powersupply and honestly, im still lost. i am not new to audio, but this DIY amp deal is a new breed of beast.
the amp will be powering 2 satelite speakers from a Klipsch Promedia 2.1 and 2 Image Dynamics ID8v3 subwoofers with D4 coils. nominal load for the sub chanel can be 4 ohms or 1 ohm. the satelite speakers have an unknown ohm rating but i would guess either 4 or 8 ohm. i really only need ~ 40W for each satelite, but these subs are rated at 300W rms(conservatively in my car they have both been powered with 500W each and wanted more) and they will be in a VERY low tuned enclosure so the more power to them the better.
if anyone can point me in the direction of a completed amp with similar specs to the link posted that includes a power supply or even just a power supply that can deliver the needed voltage/amperage to run the amp at full power i would apreciate it.
thank you for your time.
Matt
New TDA7294 2X80W 160W Subwoofer 2 1 Channe L Board Brandnew | eBay
it states that i will need a power supply. i read a few articles on here about choosing a powersupply and honestly, im still lost. i am not new to audio, but this DIY amp deal is a new breed of beast.
the amp will be powering 2 satelite speakers from a Klipsch Promedia 2.1 and 2 Image Dynamics ID8v3 subwoofers with D4 coils. nominal load for the sub chanel can be 4 ohms or 1 ohm. the satelite speakers have an unknown ohm rating but i would guess either 4 or 8 ohm. i really only need ~ 40W for each satelite, but these subs are rated at 300W rms(conservatively in my car they have both been powered with 500W each and wanted more) and they will be in a VERY low tuned enclosure so the more power to them the better.
if anyone can point me in the direction of a completed amp with similar specs to the link posted that includes a power supply or even just a power supply that can deliver the needed voltage/amperage to run the amp at full power i would apreciate it.
thank you for your time.
Matt
A transformer is used to convert the voltage coming out of your wall socket (120v in north america and 240v in europe) into the voltage needed for your particular application (20v-0v-20v AC) , VA of a transformer denotes the amount of current it can deliver......
The proper transformer will probably cost you a lot more than the amp board ......
Since this project entails wiring high current AC i would suggest you not go forward with it untill you understand what you are dealing with , you don"t want to electrocute yourself .......
Also realize that this amp board might be sold as a kit (it doesn"t say if it is assembled or not) which means you might have to solder every component on the board ......
Also you will have to use a 8 ohm subwoofer as the subwoofer can only drive 8 ohms , of your two subs are 4 ohms you could wire them in series for 8 ohms .....
The proper transformer will probably cost you a lot more than the amp board ......
Since this project entails wiring high current AC i would suggest you not go forward with it untill you understand what you are dealing with , you don"t want to electrocute yourself .......
Also realize that this amp board might be sold as a kit (it doesn"t say if it is assembled or not) which means you might have to solder every component on the board ......
Also you will have to use a 8 ohm subwoofer as the subwoofer can only drive 8 ohms , of your two subs are 4 ohms you could wire them in series for 8 ohms .....
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i can wire AC stuff. ive wired a few wall sockets as well as a fan or two. i just wasnt sure what 20v-0-20v ment. and my subs are a Dual 4 ohm voice coil. basicly each sub can be wired to 8 ohms or 2 ohms. so i guess this amp wont work for my needs then.
Matt
Matt
Sounds like you're wanting one or two of these to drive your subs : 7x TDA7293 in Parallel 555W Mono Power Amplifier Board Assembled | eBay
Being a paralleled amp, it'll drive a 1ohm load without breaking too much of a sweat (hopefully, assuming competent design and layout).
Being a paralleled amp, it'll drive a 1ohm load without breaking too much of a sweat (hopefully, assuming competent design and layout).
ok, so after doing a little bit of digging ive decided to try and convince my better half to let me pick and choose componants to power all three speakers. now i just need a bit of help deciding what to get. i would love to run 1000w to my subs but after some consideration i feel it would be a bit much considering my current full range speaker settup. so here is what i have come up with:
to power my subs.
http://http://www.ebay.com/itm/250W...34?pt=Speakers_Subwoofers&hash=item19cd5018e6
to power my satelites:
High Performance 68WX2 LM3886 Audio Amplifier Board with Power Regulator Board | eBay
master volume control:
New BK Version PGA2311 LCD Remote Volume Control Pre Amplifier with Memory Save | eBay
and a case for the 2 channel amp:
Black Aluminium Chassis DIY Audio Power Amplifier Enclosure Metal Case Vol Pot | eBay?
hopefully im not missing anything. and moreover i hope everything works like i think it will. 2 channel amp and sub amp get their full range signal from the pre-amp, the sub has a LPF that i can set from 150hz to 35hz as well as a sub level control. unfortunatly the 2 channel part doesnt have a mids/highs level adjustment.
i would love to get the kit and assemble it myself(i made a few robots/fan controls for high school projects. not super experianced but my soldering skills are above average) but i dont have the workspace or the tools to assemble any kits.
honestly if i could somehow incorperate the sub amp into the 2 channel amp and have sub, mid, and highs adjustment seperate from the main volume i would be really happy. i just have a feeling that with such underpowered full range speakers im going to have trouble blending the subs with whatever im listening to or watching(it is really fun to make the walls rattle tho, haha). i was considering 1 4.1 type settup or a 5.1 settup, but even getting a new sub amp might be pushing my limits right now. hopefully someone can shed some light on my ideas and point me in the direction of a good, solid settup that i can enjoy for years to come.
Matt
to power my subs.
http://http://www.ebay.com/itm/250W...34?pt=Speakers_Subwoofers&hash=item19cd5018e6
to power my satelites:
High Performance 68WX2 LM3886 Audio Amplifier Board with Power Regulator Board | eBay
master volume control:
New BK Version PGA2311 LCD Remote Volume Control Pre Amplifier with Memory Save | eBay
and a case for the 2 channel amp:
Black Aluminium Chassis DIY Audio Power Amplifier Enclosure Metal Case Vol Pot | eBay?
hopefully im not missing anything. and moreover i hope everything works like i think it will. 2 channel amp and sub amp get their full range signal from the pre-amp, the sub has a LPF that i can set from 150hz to 35hz as well as a sub level control. unfortunatly the 2 channel part doesnt have a mids/highs level adjustment.
i would love to get the kit and assemble it myself(i made a few robots/fan controls for high school projects. not super experianced but my soldering skills are above average) but i dont have the workspace or the tools to assemble any kits.
honestly if i could somehow incorperate the sub amp into the 2 channel amp and have sub, mid, and highs adjustment seperate from the main volume i would be really happy. i just have a feeling that with such underpowered full range speakers im going to have trouble blending the subs with whatever im listening to or watching(it is really fun to make the walls rattle tho, haha). i was considering 1 4.1 type settup or a 5.1 settup, but even getting a new sub amp might be pushing my limits right now. hopefully someone can shed some light on my ideas and point me in the direction of a good, solid settup that i can enjoy for years to come.
Matt
Well , The Chassis is too small (the needed transformer and heatsinks will dwarf the size of that chassis), you don"t have a transformer nor do you indicate you have a heatsink large enough for the amp you want to build ....
you would need a transformer of about 500Va for each sub kit and a 200Va for the stereo LM3886 kit , you will also need quite a large heasink that can accomidate all those chips ......
You might also need a beefier PSU board than the one that comes with the LM3886 kit ......
A preamp may or may not be needed depending on your audio source .....
you would need a transformer of about 500Va for each sub kit and a 200Va for the stereo LM3886 kit , you will also need quite a large heasink that can accomidate all those chips ......
You might also need a beefier PSU board than the one that comes with the LM3886 kit ......
A preamp may or may not be needed depending on your audio source .....
Could you supply us with the Schematics for these amplifiers and other electronics. Vendor Specifications are often misguided and of limited use, especially when circuits don't function as expected. It is my belief that the Schematic is central to the practice of DIY electronics.
i cant provide any schematics, and i was just throwing out the componants i found. and since i dont have the equipment to build a board myself i will have to rely on "completed" boards and assemble them myself.
as for heat i will most likley run cooling fans in a push/pul configuration along with multiple heatsinks. most of the time these amps will not be ran at even near full power so heat buildup should be minimal.
if you guys can reccomend a 2 chanel amp with ~60W at 4 ohms(i still have to check my satelite speakers ohm rating) and a sub amp that can push ~300-350W at a 4 ohm load i would apreciate it. i am still looking around to try and learn more about chip amps.
Matt
as for heat i will most likley run cooling fans in a push/pul configuration along with multiple heatsinks. most of the time these amps will not be ran at even near full power so heat buildup should be minimal.
if you guys can reccomend a 2 chanel amp with ~60W at 4 ohms(i still have to check my satelite speakers ohm rating) and a sub amp that can push ~300-350W at a 4 ohm load i would apreciate it. i am still looking around to try and learn more about chip amps.
Matt
Well the ebay LM3886 kits will put out about 65w onto 4 ohms with a +/-28v DC supply ......
If you use the same +/-28v supply for the ebay subwoofer amp you should get about 350w+ watts into 2 ohms , you could wire both sub speakers in paralell for 2 ohms and use the same amp for both subs ......
The power transformer you would need would be about 22v 0v 22v AC at about 1000Va which will run you maybe $200+ unless you could scavange one somewhere , and you also got to take in consideration the voltages needed for your volume controll and preamp ......
For your chassis i would suggest you wait till you have everything assembled and working then figure out the size and type of chassis you will need ......
I usually wait till the end of a project then figure out the dimentions i will need depending on the size of the curcuit board , heatsinks , PSU and transformer then go to a metal shop and get them to cut the pieces in need to build my own chassis .....
A lot of poeple get cought up in the amount of watts their amp has but don"t reallize the number of watts doesn"t mean a lot , its the sencitivity of your speakers means more for volume than the watts being fed into it ......
A 10w amp into a 104db speaker is going to be louder than a 100w amp into a 90db speaker .......
If you use the same +/-28v supply for the ebay subwoofer amp you should get about 350w+ watts into 2 ohms , you could wire both sub speakers in paralell for 2 ohms and use the same amp for both subs ......
The power transformer you would need would be about 22v 0v 22v AC at about 1000Va which will run you maybe $200+ unless you could scavange one somewhere , and you also got to take in consideration the voltages needed for your volume controll and preamp ......
For your chassis i would suggest you wait till you have everything assembled and working then figure out the size and type of chassis you will need ......
I usually wait till the end of a project then figure out the dimentions i will need depending on the size of the curcuit board , heatsinks , PSU and transformer then go to a metal shop and get them to cut the pieces in need to build my own chassis .....
A lot of poeple get cought up in the amount of watts their amp has but don"t reallize the number of watts doesn"t mean a lot , its the sencitivity of your speakers means more for volume than the watts being fed into it ......
A 10w amp into a 104db speaker is going to be louder than a 100w amp into a 90db speaker .......
well my speakers cannot be wired to 2 ohms. each sub is a Dual 4 ohm coil. i can wire EACH sub to 2 or 8 ohms. so the final load the amp will see(if its a monoblock) is either 1 ohm, 4 ohm, or 16 ohms.
im hopeing that i can just find a 2.1 amp that has my power needs. finding all of these parts will probobly take me forever. lol
Matt
im hopeing that i can just find a 2.1 amp that has my power needs. finding all of these parts will probobly take me forever. lol
Matt
Wire your dual VC speakers as 8ohms.
Dedicate an amplifier to each 8ohms speaker.
That way you can put out ~130W of bass power and have the flexibility to locate your amp/spkr combination anywhere in the room, twice over.
Dedicate an amplifier to each 8ohms speaker.
That way you can put out ~130W of bass power and have the flexibility to locate your amp/spkr combination anywhere in the room, twice over.
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