Team-BHP - ICE components for home speaker system???

Hi all, this is my first post in the ICE section, i am thinking of building a home speaker system, but using ICE components. I have a pair of kenwood 6"x9" 4way speakers, i'll be using a 2 channel amplifier to power them, and planning to connect them to various audio sources through the RCA connectors of the amp.

I need to know what problems i may have to face, and more importantly will it sound good?

This is what i am planning to include

1. The speakers are Kenwood KFC-6908 (peak power 220W, dunno whether it is RMS or something else)
2. Put a decent 2ch amplifier in 4k-6k budget.
3. Enclosures for the speakers. Planning to build 2 enclosures joined to each other so that it becomes a single unit with the amplifier and its PSU in between the speakers.
4. Power supply unit, 12 volt 20-25 Amperes. (I have no idea from where I'll get this.)

I don't want the speakers to be loud, what i want is a full sounding system throwing out full spectrum of sound.

Which amp shall i get? What about its power supply? can a PSU be made to order? i have read somewhere that the PSU from a computer (ATX power supply 400W at 12V ~30 Amperes) can handle the load of an low power amp. Can somebody tell me how are the amplifiers in car accessories shops powered? How to wire it up?

How much enclosure volume is required for the said speakers? Do i build an enclosure or get it built? price?

Sorry for so many questions, but I'm confused :confused:

yup..you can do it and it will sound decent..But cranking up full volume may lead to distortion.

Building boxes..the DIY..check google for more info..there are many ways to do it.and most important use a good quality MDF board and seal the box well.. The better the sealing, the better the sound..

W.r.t the amp..you will have to power it with a separate SMPS with a rated fuse or a similar arrangement.

In cars, the amps are wired with a thick wire from the battery terminal, the protection being a proper fuse / fuse link!

Quote:

Originally Posted by headers (Post 406940)

the computer smps will not work fine....as when the bass note will hit the amp will draw more current and these computer smps are not degisned to handle loads like these.....

@headers - i also think it might work well, i just wanted to know whether you have came across an amp being powered through a smps?

Todays pc's draw a lot of current, especially the hard disk and the processor draw a constant current, so IMO powering a low power amp through a smps would not be such a problem, also i got to read some more stuff about it over here Pc power supply powering car amplifier in home

@navin - i also have the same doubt that you have regarding the amp drawing large current when the bass note hits, but think of it, a 2 channel amp will draw a maximum of 2 x 110W = 220W (for a low end amp) 220W @12V = 18Amp max. Now think of a typical SMPS PSU 400W/500W @12V and 5V now if i consider a 50:50 power (Watt) split (am i right here?) between the 5V and 12V power rails, i still have 200/250W available @12V. so there is no problem. This is the theory though, so is it a good idea to try this as a DIY project? How are the amps at car accesories shops powered?
Also thanks for providing the names of these brands which i was unaware of except sonodyne, but i still am looking at the possibility to go the car amp way, it's more fun this way ain't it?

regards - IMP

Quote:

Originally Posted by IMP (Post 408023)

Todays pc's draw a lot of current, especially the hard disk and the processor draw a constant current, so IMO powering a low power amp through a smps would not be such a problem, also i got to read some more stuff about it over here Pc power supply powering car amplifier in home

@navin - i also have the same doubt that you have regarding the amp drawing large current when the bass note hits, but think of it, a 2 channel amp will draw a maximum of 2 x 110W = 220W (for a low end amp) 220W @12V = 18Amp max. Now think of a typical SMPS PSU 400W/500W @12V and 5V now if i consider a 50:50 power (Watt) split (am i right here?) between the 5V and 12V power rails, i still have 200/250W available @12V. so there is no problem. This is the theory though, so is it a good idea to try this as a DIY project? How are the amps at car accesories shops powered?
Also thanks for providing the names of these brands which i was unaware of except sonodyne, but i still am looking at the possibility to go the car amp way, it's more fun this way ain't it?

regards - IMP

the hdd in a computer consume less than 1 amps on each rail....or we can say the hdd is about 20 watts max...and the normal desktop processor is about 80 watts that also at max load......even my pc which is having 4 hdd 2 dvd writer, dual core processor and a big might 8800 series gfx with lots of fans give me 1.8 amps on the main line that is about 396 watts...which is run by a 750 watts PSU....

ok now your amp....you have said 2 x 110 watts which comes to 220 watts now the load at the supply end would not be just 220 watts but the ineffiency of the amp also added...suppose the amp is ab class so a low end amp would be 50% effecient so the load will become double that is 440 watts so the current would be....36.6 amps which a normal local computer PSU cannot deliver....as i myself have tried a pioneer 414 oldmodel amp which is capable of 35 x 4 or 70 x 2 could not work on the computer PSU.....

also some safety standards are introduced in the PSU segment that is if the smps is a big one like 700 watts it has to divide the load of 12 volts rails to max 19 amps.....so if the smps is having mutiple rails it can only supply max 19 amps which is very much less for any amp....also the cost of a good smps would be in a range of 5k above which you require to run the amp....

I would suggest ....get a car battery and car battery charger to supply power to the amp as it will be a cheapest option to run a amp.....

Quote:

Originally Posted by IMP (Post 408042)

After posting the previous post, i thought about it and decided to check out the SMPS in my comp, here are some interesting figures.

Why is -12V ampere rating so low?

the rating given on this SMPS is a full joke....I bet it cannot supply the 40 amps on the 5 volt rail......and the 28 amps on the 3.3 rail also.....the 12 volt is the most important these days....but here it is written 20 amps...i doubt it cannot supply these also.....these are all local chinese smps with you can just power up a small computer system with single HDD and cd-rom and with no display card ...as they are designed for this purpose only.....

so here is a server grade solid computer smps here are the specs.....

Quote:

Originally Posted by navin (Post 409290)

IMP I dont see any reason to use a computer power supply. If you want to try go ahead just be prepared for some smoke (no mirrors). ..... However if you insist of building a home system using a car amp you can build a SMPS for the same. There are many circuits on the internet for this. I am a big fan of DIY but there are other forums for this discussion.

Thanks a ton navin and low_bass_makker :Cheering:, now i'm convinced after this discussion that, pc smps are useless to power car amps, amps need huge amounts of current and only car batteries and special power supplies can provide such current.

build an SMPS? ..... hmmmm maybe will do it sometime later.

OT: navin could you provide some contact details for the brands you mentioned in your second post in this thread?

Quote:

Originally Posted by low_bass_makker (Post 409321)

the rating given on this SMPS is a full joke....these are all local chinese smps with you can just power up a small computer system with single HDD and cd-rom and with no display card ...as they are designed for this purpose only.....

so here is a server grade solid computer smps here are the specs.....

Thanks for the pic, those figures look more believable, but i noticed the voltages written as 12V1 12V2 12V3 ... is this because it is a server SMPS?, can we connect them in parallel so we get 16+16+16+18= 66A :confused:

About the SMPS in my pic, although it is as useless as any other PC SMPS to power an amp it does power a system with 2 HDD's, a DVD burner, graphics card, dual-core processor tv-tuner and 5 fan's without problems. But i am not saying it is a good quality smps either.

Quote:

Originally Posted by IMP (Post 410044)

OT: navin could you provide some contact details for the brands you mentioned in your second post in this thread?

Norge: Shyam Bajaj 24466627
Lithos: Rajiv Dsouza 9820121604
Sanen: Mr. Arora 98201 87582
Pandam: Prashant Damle i forget the numbers but he is in Mahim, Mumbai and so is Norge
Sonodyne: they have stores in most metros but Anandya Mukherjee is based in Calcutta or should I say Kolkutta
Torvin is based in Chennai
there are a host of other brands as well. Just pick up any old issue of AV Max and loo at the rear or email Nishant or the editors at AV Max.

Quote:

Originally Posted by IMP (Post 410044)

yes there are three parllel rails in the PSU....which can be connected in parllel to get the 60 amps figure.....

it can power on all the stuff you mentioned....but it will not be stable.....anyways which cpu and graphic card do you use....