1000 Watt LM3886 Or TDA?

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decent stuff.
was hoping for a car sub driver, then tda7294 would had been more than enough.

If i was You i would not try to build a suitable amplifier.
Maybe it would be cheaper (and a lot safer) to purchase a used one.
And probably an EQ too, subs with 40 hz at -10 dBL require such thing to function properly.
 
decent stuff.
was hoping for a car sub driver, then tda7294 would had been more than enough.

If i was You i would not try to build a suitable amplifier.
Maybe it would be cheaper (and a lot safer) to purchase a used one.
And probably an EQ too, subs with 40 hz at -10 dBL require such thing to function properly.

Literally just clicked on the TDA7294 datasheet as you posted this. I think if i decide to build my own amp i am going with the TDA7293(You can parallel/bridge better and it has a clip light). Thanks for the help! I may look into buying an amp or i may just buy an EQ and build my own amp. Also How do you know a 7294 would be more than enough? Im looking at using this to DJ.

Thanks!
 
usual cheap car subs that have nice stickers with (insert your favoured big number here) watts on them can't handle more than 100 watt. And there are a nother bunch that can handle more, but has less than 85 dBL sensitivity. (a more proper term for those is noisy space heater).

This is a decent PA speaker, and probably can handle high power, and has high sensitivity too.
Drawback is the verry narrow band it can reproduce.

Not familiar how the bridge+parallel mode works, or if those kits can do it.
Allso consider the price of a proper PSU for this setup.
And the needed heatsinking.
And speaker protection, and so on... Many things that factory made amplifiers have,
and at this level, are good to have.

I would stick with a used power amplifier in the range close to 1K watts.
Probably will cost less than a DIY attempt that may/may not work.

I think anything over 200 watt is not realy for DIY making.
And i can be prooven verry wrong :D
 
usual cheap car subs that have nice stickers with (insert your favoured big number here) watts on them can't handle more than 100 watt. And there are a nother bunch that can handle more, but has less than 85 dBL sensitivity. (a more proper term for those is noisy space heater).

This is a decent PA speaker, and probably can handle high power, and has high sensitivity too.
Drawback is the verry narrow band it can reproduce.

Not familiar how the bridge+parallel mode works, or if those kits can do it.
Allso consider the price of a proper PSU for this setup.
And the needed heatsinking.
And speaker protection, and so on... Many things that factory made amplifiers have,
and at this level, are good to have.

I would stick with a used power amplifier in the range close to 1K watts.
Probably will cost less than a DIY attempt that may/may not work.

I think anything over 200 watt is not realy for DIY making.
And i can be prooven verry wrong :D

You may be right. I may start looking into buying a used amp. It seems like a lot of work for such little wattage. I will also contact the ebay supplier and get the details on if they can bridge.

Thanks!
 
I agree with Arty. If you want serious power, buy a used amp. Visit music stores, pawn shops, check eBay for nearby auctions (no shipping charges...), try sound rental companies that could be replacing old heavy amps with fancy new digital ones. Avoid anything that has "pro" in the name since those are usually bedroom-DJ/family-room-karaoke junk, except Yorkville's respectable Audiopro amps.

In the meantime, use whatever amp you have available; use a stereo receiver or integrated amp. Run a car amp from a computer power supply.
 
That is the spec's for the speaker you tagged. If you build a real 1000 watt amplifier it will toast the speaker just from a power burp.

Comparing theoretical RMS-figures, then yes. And running testtones through them, then probably. But in real life I've run a 100Wrms amp up to (and beyond) clipping on my 30Wrms speakers for years and years, with many types of music (including modern music with horrible crest factors) and they still live.
(BTW, they were run of off a set of 1000Wrms amps too :eek:, but not into clipping:firefite:: they are far too valuable to me to have them die on me... :RIP:)

Still, I agree it's probably better in this case to match the power of the amp to the speakers to minimize the chance of blowing them up...:D
And from what I've heard of Behringer, they might not have the tolerance for abuse that my speakers (1970's Pioneers) have.
 
Comparing theoretical RMS-figures, then yes. And running testtones through them, then probably. But in real life I've run a 100Wrms amp up to (and beyond) clipping on my 30Wrms speakers for years and years, with many types of music (including modern music with horrible crest factors) and they still live.
(BTW, they were run of off a set of 1000Wrms amps too :eek:, but not into clipping:firefite:: they are far too valuable to me to have them die on me... :RIP:)

Still, I agree it's probably better in this case to match the power of the amp to the speakers to minimize the chance of blowing them up...:D
And from what I've heard of Behringer, they might not have the tolerance for abuse that my speakers (1970's Pioneers) have.

When I deliberately toasted Pioneer drivers the ones rated for 10 watts failed at 35 - 45 watts. That is due to the older method of rating power. It used to be a 100 hour test. The loudspeaker in question is spec'd to an IEC standard that limits the bandwidth to 100 to 250 Hz. It also is a much shorter period.

Now just by shortening the test you get at least a 30% higher rating. Limiting the bandwidth is important for a woofer as the inductance rises so the high frequency energy really doesn't count. The problem is that 100 Hz. is too high a frequency to test a subwoofer. As you probably know when you halve the frequency you have four times the cone movement for the same energy. So a subwoofer rated at 450 watts at 100 Hz will probably have over excursion at 40 Hz 72 watts. Of course as this woofer shows a fairly high sensitivity that indicated a smaller voice coil gap, which particularly since the size is not shown, a small diameter voice coil.

Now the 450 watt rating is also not as robust as the standard your speaker's used. So under that this would be a 300 watt or less rating.

Then the issue of clipping. You will notice this much more easily on a full range loudspeaker system than on a sub woofer.

That is why a real 1000 Watt amplifier will most likely ruin the loudspeaker.
 
When I deliberately toasted Pioneer drivers the ones rated for 10 watts failed at 35 - 45 watts.

:eek: You speakermurderer...

Thanks for clarifying the the flaws in my comparison!

Did some searching but could not find much more about the sub of the OP. The chassis used is mentioned, as you may have seen, but specs (with a quick-search) are nowhere to be found on the net. :(
 
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If you drop the load down to 1 ohm you can get about 800watts out of a bunch (32, I think) of LM3886, but why would you want to do it?

I would, I'm building a 10cu.ft crawlspace subwoofer with eight 10" cheap subwoofers - think really cheap, below 83dB and excursion limited, say 40-60watts depending on how low I want to go - off a 400W power amplifier. Each sub is 8 ohms, so I'm paralleling them all up and running them off 8 parallel LM3886TF.

I could run each sub off its own little chipamp but I would need a lot of wire going into the crawlspace (tubes are laid already). The amps are powered off two basic supplies and are going to be limited to an output of 20V p-p, to keep power output under a leash as the TF doesn't do too great in dissipating heat. That gives a nice healthy 400W maximum power output, which should be more than needed for my 22x22 room.

I figure with 8 83dB subs I would get quite a bit of output at listening position with less than 100 watts, the paralleling is only to ensure I get the capability to drive 1 ohm without toasting the chips or worse, activating the horrible SpiKE protection. The biggest reason for doing this was because I had most of the parts already, just needed to get the subwoofers and the remote trigger circuit.

I thought about 4 Eminence Lab12 woofers instead, but those cost about 3x of what I paid for these ones, so I figured this would be a cool way to empty out my parts bin and get something useful going.
 
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^^Too cheap to buy new stuff, Nigel. I do agree it's not the best solution, so I do have a nice pro amp on hold but no funds and lots of free time and chips, transformers, heatsinks, fans, caps etc - this is a couple afternoons' work with a high potential reward/risk ratio (for me).

For new builders though, I would agree with your approach (and that of most on the thread).

FWIW my present amplifier has 4 LM4780 chips running in fully balanced mode, for about 200W/ch into 4 ohms. That is 8 chip dies, just done differently.
 
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