AMP5 for active sub woofer?

[StalfoS]

Hi,

I have not built any of the 41Hz amps before, but I am interested in trying. I want to build an amp with about 100W power to mount inside my sub woofer. It is an 8inch driver so not too big, I am wondering if AMP5 is a good choice. I have a few questions:

-Is it possible to order AMP5 in a mono configuration? (I plan on summing L+R, so only need one channel)

-Is it possible to power an active crossover off with the +/- 5V power supply?

[StalfoS]

Ok... so the TA2022 is a stereo chip.. i'm dumb.

I guess the question is then if I bridge it will it be too powerful for my driver?

Hmmm.. I'm not even sure the impedance of my driver. It is a Mission 70ASA but I cant find the specs on it. hmmm....

[nightfire]

quote:Originally posted by StalfoS
[br]Ok... so the TA2022 is a stereo chip.. i'm dumb.

I guess the question is then if I bridge it will it be too powerful for my driver?

Hmmm.. I'm not even sure the impedance of my driver. It is a Mission 70ASA but I cant find the specs on it. hmmm....


It is bridgeable with a simple modification detailed in the manual. I think it would work perfectly for a small sub (even at 4 ohms) but you'd probably want the high power kit (2 extra caps and an extra rectifier).

Note however I've never tried this and in fact I munged the assembly of my board and am waiting on a replacement. Just going by what I've read. :)

- Gord

[StalfoS]

Well the DC resistance across the driver is 3.3 Ohms, so I'm guessing the nominal impedance is in the range of 4 Ohms.

[thomaseliot]

quote:Originally posted by StalfoS
[br]Well the DC resistance across the driver is 3.3 Ohms, so I'm guessing the nominal impedance is in the range of 4 Ohms.


Quote from TA2022 datasheet:

"When the two amplifier outputs are bridged, the apparent load impedance seen by each output is halved, so the minimum recommended impedance for bridged operation is 8 ohms..... Bridged operation into loads below 8ohms is possible, but, as mentioned above, the amplifier efficiency will be reduced and the amplifier may prematurely current limit."

With 4 ohm load a bridged amp would "see" 2 ohm and would be capable of 400W: but internal current limiter would stop the amp.

With 4 ohm load TA2022 is 100W at 1% thd+n or 0,1% THD+N at 90W. Maybe you can parallel the two channels to double the power.

[xenob]

I did juse the TA2022 in bridge mode with a 4ohm woofer. The heatsink had to bee increased afterwards it could handle the load quite well.

[karsk]

Hi,

i`ve read that Denon are using TA2022 in one of their new subwoofers with a 25cm woofer. I dont know if their using it with a bridged 8ohm load or less. I think the amp5 is not to short of power to manage a nice rumble, if u build it with care.