Audio Amplifier for home made sub

Y

yusuf

Adept
Guys,

Can someone help me in finding amplifier for my home made Subwoofer. Sub is based on JBL1202 driver and I will be driving it from either Yamha 659 or Denon 2307. I am thinking of using a car amplifier but I was wondering if is there any better and cost effective option like plate amplifier, kits etc.

This is an experimental subwoofer morever doing for for learning speaker building and I do not want to spend very high amount.

Thanks for your inputs and help.
 
Nope, nothing there, but I have a few odds and ends you may be able to use if you're hacking something together. Some transformers, caps and chips. PM me if interested. I also have a beast of an amp of which one channel is not working but the other one is usable as a power amp. You'll HAVE to get it picked up in Mumbai though.

I see you used the JBL - good call over the Peerless.

I would think a car amp + a battery + a charger would be a decent setup, or if you have someone coming in from abroad you could ask them for a plate amp, pretty common to find.

You can try a bridged chipamp setup. The boards used to be available in Bangalore about 10 years back, don't know about now. Two TDA 7294 chips can put out about 100WRMS into an 8 ohm load when bridged, so that would be good and cheap if you could do that.

If you like the DIY route you have quite a few options actually, and some of very high quality. The problem is chassis related, as those are the difficult bits to get your hands on.

Local HT manufacturers could also knock something together for you, you might want to ask around. We have a few of them in Mumbai (choudhary is one) who are not totally averse to custom jobs.

Or you could get a stereo amp for cheap and run the sub off of that. I'm not sure there are any for very cheap, the lowest I am aware of are the local HT amps, and I wouldn't trust them at all. You might have some luck with the entry-level 'professional' amps, look for somthing with about 100WRMS and run the sub off the low-impedance taps. These are the type used for marriages and functions, and some could be available at low prices. But this would really be scraping the bottom of the barrell.

Exactly what is your budget?

@nukeu: I'm Sangram, not Sangam, thanks!
 
Thanks Sangram for inputs.

Actually I was in US last month but it was kind of quick trip to order anything online. Anyway, I have a carpenter at home so better get it done asap :)

I thought of using two ATX power supply in parallel with car amplifier so that I can use in bridge mode. But that would be last option (one ATX power supply will be enough for 60-70 watts but not higher specially in bridge mode).

Another option as you suggested is based on TDA 7293/7294 or LM3886 but I was prefering ready PCB which I could not find? Any inputs?

I am not sure those PA amplifier will perform at lower end. But that also seems to be a option...I will check it out.

Can you put some more light on DIY option you mentioned. I am fine with handling circuits so that should not be problem.

Budget for amp is approx 2-3K.
 
back home in kerala , these sort of amp boards are a cottage industry :D

dunno how it is in b'lore. I've looked for those types of electronics shops, didnt see any
 
yusuf said:
Budget for amp is approx 2-3K.
Click to expand...

Yup, then you can probably get a dual mono kit for the LM4780 here: DIY Chip Amplifier Kits, PCB's, Components and Information.. It'll take you half an hour to put it together and all you need to connect it is a transformer and heatsinks. If you don't have a balanced output you can bridge it using a single resistor, write to me and I'll tell you how, or look up Rod Elliot's site.

That amp will easily put out 200 watts RMS, and will just squeeze into your budget. The only things you need to add are transformer, heatsink and (because you are making a sub) some large caps for the PS.

Hold it, I just checked again, and the prices have gone up quite a bit, it's $73 for the kit plus $11 shipping, so after adding the big bits that's a bit out of your budget. But it's still pretty good, I have two of those boards powering my main system and they could power a toaster if they had to. May still be worth the expense.

For LM3886 you don't even need a board, it's way too simple and can be wired up P2P (ratsnest) in an hour. But if you're still keen, there are some options here: DIY Chip Amplifier Kits, PCB's, Components and Information.

These guys take Paypal, and I can vouch for Peter at audiosector, he's top-notch to deal with. He shipped stuff by ordinary post and I got them in five days, no duty to be paid as they're all parts.
 
Thanks buddy. I did not consider 4780 earlier. Is chip available locally ? In that case I can order only PCB.

Yusuf
 
Nope.

I did have a few pieces but used 'em all up. You can ask Peter to send only the chips and PCB, and get everything else to save a bit. The rectifiers and caps he supplies actually cost quite a lot (and really help the sound), you can tell him you're a student and he'll only send you those.
 
Sure, I will ask him.

Btw, what is your suggestion on using car amplifier (Sony xplod is cheapest one around rs. 2800 but not sure of quality).
 
Don't.

Car amps are not rated for home use. The cheaper ones are about 50 watts a channel, and in a car since you get 6db cabin gain you can get by. In a home environment you need good, clean power to go into a sub. I actually don't think the idea of using anything made for a car in a home environment.

Unless you're hard-up on cash. Then even a cheap car amp with an ATX supply will work for some.

Once you get to the high dollar amps those will work (Rockford Fosgate) as well as a home sub amp, but those cost just as much as a home amp...
 
BTW I saw you registered at DIYaudio. That place will ensure you get poorer very quickly, with all the experimenting and building you'll do. Good call.
 
sangram said:
Don't.
Car amps are not rated for home use. The cheaper ones are about 50 watts a channel, and in a car since you get 6db cabin gain you can get by. In a home environment you need good, clean power to go into a sub. I actually don't think the idea of using anything made for a car in a home environment.
Click to expand...

How about bridging. Most car amplifier I saw are bridgeable to deliver approx 110W RMS.

Also, what is your opinion on quality. Will it be big quality difference if wattage remain same between 4780 vs caramp(Sony, pioneer) option.

To give more information, Sub driver is JBL 1202 (again car sub) with sealed enclusure of approx 2 cft (qtc = .8) and down firing.
 
110WRMS, at 10% THD. Running off an ATX supply.

versus about 150 -200 watts (depending on supply voltage and heatsinking). At .5% or better THD. Running off a good linear supply.

Call is yours.
 
May be I am missing something but sony xplod specification mentions .1% THD at 4ohm in BTL model, 130W

I agree about your point on ATX power supply.
 
the major differnce in the car audio amp and a home audio amp is the supply voltage....

in the car audio amp the supply is 12 volts to 14 volts...which is step-up using a dc-dc converter to higher voltages....or as per wattage reqirements......so it will be a waste of energy...but in a home audio amp the voltages are step down to the level they are required...........

also the atx supply will not able to provide the juice to the car amp as when a BASS note hits there is a huge surge at the supply end.....

if your budget is a issue get a car amp with a little more power (like there are fake alpine 4-ch amps sell for 3.2k good value for money you can bridge and drive 2 subs with that) which can run the subs....the sony 222 is a very small amp capable of drive a pair of speakers not the subs....connect them to a car battery and a battery charger it will do the trick.....
 
yusuf said:
May be I am missing something but sony xplod specification mentions .1% THD at 4ohm in BTL model, 130W
Click to expand...

Then maybe they've done something to their amps, because I don't know the Xplod amps are good for anything, except producing distortion...

The best option is to build a good discrete amplifier with a nice power supply, even if it's only 80 watts it'll have enough juice for that sub of yours, or get someone to get you a nice plate amp.

In a pinch I guess you could use a car amp. It's really up to you. I wouldn't, but that's just me...
 
Back
Top