What size amp should i get for performance teknique sub-woofers

Probably not. Somewhere there is a filter (crossover) that only sends the lower frequencies to the sub-woofer driver. Where that filter resides (either in the pre-amp, receiver or sub-woofer enclosure is yet to be known).

Sub woofers have small amplifiers , not transformers. The amplifier is removable and replaceable. The The overall size and the output wattage are the spec's you need . The output wattage is on the label which is attached somewhere on the speaker. You do NOT need to replace the amp with the Altec Lansing brand. Have you contacted Altec Lansing to purchase a replacement Amp? That's where I would start. If they cannot help you I would Google replacement amp sub-woofer, Altec Lansing model MX5021.
good luck

hi,
Do you mean sub woofer. Then you can select any brands Active sub woofer ( active means built in amplifier) to connect with your system. They comes in different power (watts). you can use an active sub woofer with 100W output.
connect the sub woofer pre out of you amp to the pre input of sub woofer.
ok

hi,
if u want to hook up the sub with ur av receiver the connect the sub woofer output of ur AVR to any one (left or right) input of ur sub woofer. then connect its power . set the frequency range between 90 and 120Hz. set the volume of sub woofer to 40% of its total. also check the av receives speaker setting. goto speaker setup and make ON the sub woofer out.

if want to connect the sub to a stereo amp without sub out. then connect the amps speaker line to the speaker input of sub woofer and connect the speaker out of sub to left and right speaker ( make sure to connect the red to red and black to black). set the volume and frequency as above
ok

hi,
if ur amplifier have a pre out, then u can connect that to ur L/R input of ur sub woofer.

if not the only way is, connect ur amplifiers speaker output to sub woofers speaker input and then connect ur speaker to sub woofer speaker output terminal. remember don't inter change positive and negative wires.

if ur amplifier have speaker A,B connection then it is very easy. connect the speaker A to ur left and right speaker. then connect speaker B to ur sub woofer's left and right speaker input. be sure to make that speaker A and B switch is in on position. the power on both and check it. ( use good quality speaker cable to connect the sub woofer)

your sub woofer is designed to work , both at low level and high level input.
ok

You will need an amplifier or 2 channel receiver. Hook the sub out rca jack to the rca inputs on this new amp or receiver and hook the speaker terminals on sub to speaker terminals on same amp or receiver. Your Yamaha receiver doesn't have any power for a passive sub.Just pick up any old fairly high powered receiver for fifty dollars and you're good to go.I use old dolby pro logic receivers as they are a dime a dozen today. Good luck.

It is based on your sub-woofer type..whether powered or passive sub woofer..
Assume that you have powered one..RCA sub woofer jack is the best to feed it ..you should use RCA sub woofer output on your receiver as well..good luck

so that ok wont do no harm my friend

Get a powered sub-woofer that has speaker level inputs, then run your front speaker wires into the sub-woofers speaker level input and then run a set of speaker wires from the sub-woofers speaker wire output to your front speakers. This is a common way to use a sub-woofer with a receiver that doesn't have a sub-woofer output.

Most powered sub-woofers have these connections, just check it out first before you buy one. They look like speaker jacks on the back of the receiver.

Let me know if you have any other questions.

You may have a defective speaker or a wiring fault. Disconnect the speaker from the amp and measure the resistance across the speaker wires. The resistance should be near the rated impedance of the speaker.